sge.c 80 KB

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  1. /*
  2. * This file is part of the Chelsio T4 PCI-E SR-IOV Virtual Function Ethernet
  3. * driver for Linux.
  4. *
  5. * Copyright (c) 2009-2010 Chelsio Communications, Inc. All rights reserved.
  6. *
  7. * This software is available to you under a choice of one of two
  8. * licenses. You may choose to be licensed under the terms of the GNU
  9. * General Public License (GPL) Version 2, available from the file
  10. * COPYING in the main directory of this source tree, or the
  11. * OpenIB.org BSD license below:
  12. *
  13. * Redistribution and use in source and binary forms, with or
  14. * without modification, are permitted provided that the following
  15. * conditions are met:
  16. *
  17. * - Redistributions of source code must retain the above
  18. * copyright notice, this list of conditions and the following
  19. * disclaimer.
  20. *
  21. * - Redistributions in binary form must reproduce the above
  22. * copyright notice, this list of conditions and the following
  23. * disclaimer in the documentation and/or other materials
  24. * provided with the distribution.
  25. *
  26. * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  27. * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  28. * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  29. * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  30. * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  31. * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  32. * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  33. * SOFTWARE.
  34. */
  35. #include <linux/skbuff.h>
  36. #include <linux/netdevice.h>
  37. #include <linux/etherdevice.h>
  38. #include <linux/if_vlan.h>
  39. #include <linux/ip.h>
  40. #include <net/ipv6.h>
  41. #include <net/tcp.h>
  42. #include <linux/dma-mapping.h>
  43. #include <linux/prefetch.h>
  44. #include "t4vf_common.h"
  45. #include "t4vf_defs.h"
  46. #include "../cxgb4/t4_regs.h"
  47. #include "../cxgb4/t4_values.h"
  48. #include "../cxgb4/t4fw_api.h"
  49. #include "../cxgb4/t4_msg.h"
  50. /*
  51. * Constants ...
  52. */
  53. enum {
  54. /*
  55. * Egress Queue sizes, producer and consumer indices are all in units
  56. * of Egress Context Units bytes. Note that as far as the hardware is
  57. * concerned, the free list is an Egress Queue (the host produces free
  58. * buffers which the hardware consumes) and free list entries are
  59. * 64-bit PCI DMA addresses.
  60. */
  61. EQ_UNIT = SGE_EQ_IDXSIZE,
  62. FL_PER_EQ_UNIT = EQ_UNIT / sizeof(__be64),
  63. TXD_PER_EQ_UNIT = EQ_UNIT / sizeof(__be64),
  64. /*
  65. * Max number of TX descriptors we clean up at a time. Should be
  66. * modest as freeing skbs isn't cheap and it happens while holding
  67. * locks. We just need to free packets faster than they arrive, we
  68. * eventually catch up and keep the amortized cost reasonable.
  69. */
  70. MAX_TX_RECLAIM = 16,
  71. /*
  72. * Max number of Rx buffers we replenish at a time. Again keep this
  73. * modest, allocating buffers isn't cheap either.
  74. */
  75. MAX_RX_REFILL = 16,
  76. /*
  77. * Period of the Rx queue check timer. This timer is infrequent as it
  78. * has something to do only when the system experiences severe memory
  79. * shortage.
  80. */
  81. RX_QCHECK_PERIOD = (HZ / 2),
  82. /*
  83. * Period of the TX queue check timer and the maximum number of TX
  84. * descriptors to be reclaimed by the TX timer.
  85. */
  86. TX_QCHECK_PERIOD = (HZ / 2),
  87. MAX_TIMER_TX_RECLAIM = 100,
  88. /*
  89. * Suspend an Ethernet TX queue with fewer available descriptors than
  90. * this. We always want to have room for a maximum sized packet:
  91. * inline immediate data + MAX_SKB_FRAGS. This is the same as
  92. * calc_tx_flits() for a TSO packet with nr_frags == MAX_SKB_FRAGS
  93. * (see that function and its helpers for a description of the
  94. * calculation).
  95. */
  96. ETHTXQ_MAX_FRAGS = MAX_SKB_FRAGS + 1,
  97. ETHTXQ_MAX_SGL_LEN = ((3 * (ETHTXQ_MAX_FRAGS-1))/2 +
  98. ((ETHTXQ_MAX_FRAGS-1) & 1) +
  99. 2),
  100. ETHTXQ_MAX_HDR = (sizeof(struct fw_eth_tx_pkt_vm_wr) +
  101. sizeof(struct cpl_tx_pkt_lso_core) +
  102. sizeof(struct cpl_tx_pkt_core)) / sizeof(__be64),
  103. ETHTXQ_MAX_FLITS = ETHTXQ_MAX_SGL_LEN + ETHTXQ_MAX_HDR,
  104. ETHTXQ_STOP_THRES = 1 + DIV_ROUND_UP(ETHTXQ_MAX_FLITS, TXD_PER_EQ_UNIT),
  105. /*
  106. * Max TX descriptor space we allow for an Ethernet packet to be
  107. * inlined into a WR. This is limited by the maximum value which
  108. * we can specify for immediate data in the firmware Ethernet TX
  109. * Work Request.
  110. */
  111. MAX_IMM_TX_PKT_LEN = FW_WR_IMMDLEN_M,
  112. /*
  113. * Max size of a WR sent through a control TX queue.
  114. */
  115. MAX_CTRL_WR_LEN = 256,
  116. /*
  117. * Maximum amount of data which we'll ever need to inline into a
  118. * TX ring: max(MAX_IMM_TX_PKT_LEN, MAX_CTRL_WR_LEN).
  119. */
  120. MAX_IMM_TX_LEN = (MAX_IMM_TX_PKT_LEN > MAX_CTRL_WR_LEN
  121. ? MAX_IMM_TX_PKT_LEN
  122. : MAX_CTRL_WR_LEN),
  123. /*
  124. * For incoming packets less than RX_COPY_THRES, we copy the data into
  125. * an skb rather than referencing the data. We allocate enough
  126. * in-line room in skb's to accommodate pulling in RX_PULL_LEN bytes
  127. * of the data (header).
  128. */
  129. RX_COPY_THRES = 256,
  130. RX_PULL_LEN = 128,
  131. /*
  132. * Main body length for sk_buffs used for RX Ethernet packets with
  133. * fragments. Should be >= RX_PULL_LEN but possibly bigger to give
  134. * pskb_may_pull() some room.
  135. */
  136. RX_SKB_LEN = 512,
  137. };
  138. /*
  139. * Software state per TX descriptor.
  140. */
  141. struct tx_sw_desc {
  142. struct sk_buff *skb; /* socket buffer of TX data source */
  143. struct ulptx_sgl *sgl; /* scatter/gather list in TX Queue */
  144. };
  145. /*
  146. * Software state per RX Free List descriptor. We keep track of the allocated
  147. * FL page, its size, and its PCI DMA address (if the page is mapped). The FL
  148. * page size and its PCI DMA mapped state are stored in the low bits of the
  149. * PCI DMA address as per below.
  150. */
  151. struct rx_sw_desc {
  152. struct page *page; /* Free List page buffer */
  153. dma_addr_t dma_addr; /* PCI DMA address (if mapped) */
  154. /* and flags (see below) */
  155. };
  156. /*
  157. * The low bits of rx_sw_desc.dma_addr have special meaning. Note that the
  158. * SGE also uses the low 4 bits to determine the size of the buffer. It uses
  159. * those bits to index into the SGE_FL_BUFFER_SIZE[index] register array.
  160. * Since we only use SGE_FL_BUFFER_SIZE0 and SGE_FL_BUFFER_SIZE1, these low 4
  161. * bits can only contain a 0 or a 1 to indicate which size buffer we're giving
  162. * to the SGE. Thus, our software state of "is the buffer mapped for DMA" is
  163. * maintained in an inverse sense so the hardware never sees that bit high.
  164. */
  165. enum {
  166. RX_LARGE_BUF = 1 << 0, /* buffer is SGE_FL_BUFFER_SIZE[1] */
  167. RX_UNMAPPED_BUF = 1 << 1, /* buffer is not mapped */
  168. };
  169. /**
  170. * get_buf_addr - return DMA buffer address of software descriptor
  171. * @sdesc: pointer to the software buffer descriptor
  172. *
  173. * Return the DMA buffer address of a software descriptor (stripping out
  174. * our low-order flag bits).
  175. */
  176. static inline dma_addr_t get_buf_addr(const struct rx_sw_desc *sdesc)
  177. {
  178. return sdesc->dma_addr & ~(dma_addr_t)(RX_LARGE_BUF | RX_UNMAPPED_BUF);
  179. }
  180. /**
  181. * is_buf_mapped - is buffer mapped for DMA?
  182. * @sdesc: pointer to the software buffer descriptor
  183. *
  184. * Determine whether the buffer associated with a software descriptor in
  185. * mapped for DMA or not.
  186. */
  187. static inline bool is_buf_mapped(const struct rx_sw_desc *sdesc)
  188. {
  189. return !(sdesc->dma_addr & RX_UNMAPPED_BUF);
  190. }
  191. /**
  192. * need_skb_unmap - does the platform need unmapping of sk_buffs?
  193. *
  194. * Returns true if the platform needs sk_buff unmapping. The compiler
  195. * optimizes away unnecessary code if this returns true.
  196. */
  197. static inline int need_skb_unmap(void)
  198. {
  199. #ifdef CONFIG_NEED_DMA_MAP_STATE
  200. return 1;
  201. #else
  202. return 0;
  203. #endif
  204. }
  205. /**
  206. * txq_avail - return the number of available slots in a TX queue
  207. * @tq: the TX queue
  208. *
  209. * Returns the number of available descriptors in a TX queue.
  210. */
  211. static inline unsigned int txq_avail(const struct sge_txq *tq)
  212. {
  213. return tq->size - 1 - tq->in_use;
  214. }
  215. /**
  216. * fl_cap - return the capacity of a Free List
  217. * @fl: the Free List
  218. *
  219. * Returns the capacity of a Free List. The capacity is less than the
  220. * size because an Egress Queue Index Unit worth of descriptors needs to
  221. * be left unpopulated, otherwise the Producer and Consumer indices PIDX
  222. * and CIDX will match and the hardware will think the FL is empty.
  223. */
  224. static inline unsigned int fl_cap(const struct sge_fl *fl)
  225. {
  226. return fl->size - FL_PER_EQ_UNIT;
  227. }
  228. /**
  229. * fl_starving - return whether a Free List is starving.
  230. * @adapter: pointer to the adapter
  231. * @fl: the Free List
  232. *
  233. * Tests specified Free List to see whether the number of buffers
  234. * available to the hardware has falled below our "starvation"
  235. * threshold.
  236. */
  237. static inline bool fl_starving(const struct adapter *adapter,
  238. const struct sge_fl *fl)
  239. {
  240. const struct sge *s = &adapter->sge;
  241. return fl->avail - fl->pend_cred <= s->fl_starve_thres;
  242. }
  243. /**
  244. * map_skb - map an skb for DMA to the device
  245. * @dev: the egress net device
  246. * @skb: the packet to map
  247. * @addr: a pointer to the base of the DMA mapping array
  248. *
  249. * Map an skb for DMA to the device and return an array of DMA addresses.
  250. */
  251. static int map_skb(struct device *dev, const struct sk_buff *skb,
  252. dma_addr_t *addr)
  253. {
  254. const skb_frag_t *fp, *end;
  255. const struct skb_shared_info *si;
  256. *addr = dma_map_single(dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
  257. if (dma_mapping_error(dev, *addr))
  258. goto out_err;
  259. si = skb_shinfo(skb);
  260. end = &si->frags[si->nr_frags];
  261. for (fp = si->frags; fp < end; fp++) {
  262. *++addr = skb_frag_dma_map(dev, fp, 0, skb_frag_size(fp),
  263. DMA_TO_DEVICE);
  264. if (dma_mapping_error(dev, *addr))
  265. goto unwind;
  266. }
  267. return 0;
  268. unwind:
  269. while (fp-- > si->frags)
  270. dma_unmap_page(dev, *--addr, skb_frag_size(fp), DMA_TO_DEVICE);
  271. dma_unmap_single(dev, addr[-1], skb_headlen(skb), DMA_TO_DEVICE);
  272. out_err:
  273. return -ENOMEM;
  274. }
  275. static void unmap_sgl(struct device *dev, const struct sk_buff *skb,
  276. const struct ulptx_sgl *sgl, const struct sge_txq *tq)
  277. {
  278. const struct ulptx_sge_pair *p;
  279. unsigned int nfrags = skb_shinfo(skb)->nr_frags;
  280. if (likely(skb_headlen(skb)))
  281. dma_unmap_single(dev, be64_to_cpu(sgl->addr0),
  282. be32_to_cpu(sgl->len0), DMA_TO_DEVICE);
  283. else {
  284. dma_unmap_page(dev, be64_to_cpu(sgl->addr0),
  285. be32_to_cpu(sgl->len0), DMA_TO_DEVICE);
  286. nfrags--;
  287. }
  288. /*
  289. * the complexity below is because of the possibility of a wrap-around
  290. * in the middle of an SGL
  291. */
  292. for (p = sgl->sge; nfrags >= 2; nfrags -= 2) {
  293. if (likely((u8 *)(p + 1) <= (u8 *)tq->stat)) {
  294. unmap:
  295. dma_unmap_page(dev, be64_to_cpu(p->addr[0]),
  296. be32_to_cpu(p->len[0]), DMA_TO_DEVICE);
  297. dma_unmap_page(dev, be64_to_cpu(p->addr[1]),
  298. be32_to_cpu(p->len[1]), DMA_TO_DEVICE);
  299. p++;
  300. } else if ((u8 *)p == (u8 *)tq->stat) {
  301. p = (const struct ulptx_sge_pair *)tq->desc;
  302. goto unmap;
  303. } else if ((u8 *)p + 8 == (u8 *)tq->stat) {
  304. const __be64 *addr = (const __be64 *)tq->desc;
  305. dma_unmap_page(dev, be64_to_cpu(addr[0]),
  306. be32_to_cpu(p->len[0]), DMA_TO_DEVICE);
  307. dma_unmap_page(dev, be64_to_cpu(addr[1]),
  308. be32_to_cpu(p->len[1]), DMA_TO_DEVICE);
  309. p = (const struct ulptx_sge_pair *)&addr[2];
  310. } else {
  311. const __be64 *addr = (const __be64 *)tq->desc;
  312. dma_unmap_page(dev, be64_to_cpu(p->addr[0]),
  313. be32_to_cpu(p->len[0]), DMA_TO_DEVICE);
  314. dma_unmap_page(dev, be64_to_cpu(addr[0]),
  315. be32_to_cpu(p->len[1]), DMA_TO_DEVICE);
  316. p = (const struct ulptx_sge_pair *)&addr[1];
  317. }
  318. }
  319. if (nfrags) {
  320. __be64 addr;
  321. if ((u8 *)p == (u8 *)tq->stat)
  322. p = (const struct ulptx_sge_pair *)tq->desc;
  323. addr = ((u8 *)p + 16 <= (u8 *)tq->stat
  324. ? p->addr[0]
  325. : *(const __be64 *)tq->desc);
  326. dma_unmap_page(dev, be64_to_cpu(addr), be32_to_cpu(p->len[0]),
  327. DMA_TO_DEVICE);
  328. }
  329. }
  330. /**
  331. * free_tx_desc - reclaims TX descriptors and their buffers
  332. * @adapter: the adapter
  333. * @tq: the TX queue to reclaim descriptors from
  334. * @n: the number of descriptors to reclaim
  335. * @unmap: whether the buffers should be unmapped for DMA
  336. *
  337. * Reclaims TX descriptors from an SGE TX queue and frees the associated
  338. * TX buffers. Called with the TX queue lock held.
  339. */
  340. static void free_tx_desc(struct adapter *adapter, struct sge_txq *tq,
  341. unsigned int n, bool unmap)
  342. {
  343. struct tx_sw_desc *sdesc;
  344. unsigned int cidx = tq->cidx;
  345. struct device *dev = adapter->pdev_dev;
  346. const int need_unmap = need_skb_unmap() && unmap;
  347. sdesc = &tq->sdesc[cidx];
  348. while (n--) {
  349. /*
  350. * If we kept a reference to the original TX skb, we need to
  351. * unmap it from PCI DMA space (if required) and free it.
  352. */
  353. if (sdesc->skb) {
  354. if (need_unmap)
  355. unmap_sgl(dev, sdesc->skb, sdesc->sgl, tq);
  356. dev_consume_skb_any(sdesc->skb);
  357. sdesc->skb = NULL;
  358. }
  359. sdesc++;
  360. if (++cidx == tq->size) {
  361. cidx = 0;
  362. sdesc = tq->sdesc;
  363. }
  364. }
  365. tq->cidx = cidx;
  366. }
  367. /*
  368. * Return the number of reclaimable descriptors in a TX queue.
  369. */
  370. static inline int reclaimable(const struct sge_txq *tq)
  371. {
  372. int hw_cidx = be16_to_cpu(tq->stat->cidx);
  373. int reclaimable = hw_cidx - tq->cidx;
  374. if (reclaimable < 0)
  375. reclaimable += tq->size;
  376. return reclaimable;
  377. }
  378. /**
  379. * reclaim_completed_tx - reclaims completed TX descriptors
  380. * @adapter: the adapter
  381. * @tq: the TX queue to reclaim completed descriptors from
  382. * @unmap: whether the buffers should be unmapped for DMA
  383. *
  384. * Reclaims TX descriptors that the SGE has indicated it has processed,
  385. * and frees the associated buffers if possible. Called with the TX
  386. * queue locked.
  387. */
  388. static inline void reclaim_completed_tx(struct adapter *adapter,
  389. struct sge_txq *tq,
  390. bool unmap)
  391. {
  392. int avail = reclaimable(tq);
  393. if (avail) {
  394. /*
  395. * Limit the amount of clean up work we do at a time to keep
  396. * the TX lock hold time O(1).
  397. */
  398. if (avail > MAX_TX_RECLAIM)
  399. avail = MAX_TX_RECLAIM;
  400. free_tx_desc(adapter, tq, avail, unmap);
  401. tq->in_use -= avail;
  402. }
  403. }
  404. /**
  405. * get_buf_size - return the size of an RX Free List buffer.
  406. * @adapter: pointer to the associated adapter
  407. * @sdesc: pointer to the software buffer descriptor
  408. */
  409. static inline int get_buf_size(const struct adapter *adapter,
  410. const struct rx_sw_desc *sdesc)
  411. {
  412. const struct sge *s = &adapter->sge;
  413. return (s->fl_pg_order > 0 && (sdesc->dma_addr & RX_LARGE_BUF)
  414. ? (PAGE_SIZE << s->fl_pg_order) : PAGE_SIZE);
  415. }
  416. /**
  417. * free_rx_bufs - free RX buffers on an SGE Free List
  418. * @adapter: the adapter
  419. * @fl: the SGE Free List to free buffers from
  420. * @n: how many buffers to free
  421. *
  422. * Release the next @n buffers on an SGE Free List RX queue. The
  423. * buffers must be made inaccessible to hardware before calling this
  424. * function.
  425. */
  426. static void free_rx_bufs(struct adapter *adapter, struct sge_fl *fl, int n)
  427. {
  428. while (n--) {
  429. struct rx_sw_desc *sdesc = &fl->sdesc[fl->cidx];
  430. if (is_buf_mapped(sdesc))
  431. dma_unmap_page(adapter->pdev_dev, get_buf_addr(sdesc),
  432. get_buf_size(adapter, sdesc),
  433. PCI_DMA_FROMDEVICE);
  434. put_page(sdesc->page);
  435. sdesc->page = NULL;
  436. if (++fl->cidx == fl->size)
  437. fl->cidx = 0;
  438. fl->avail--;
  439. }
  440. }
  441. /**
  442. * unmap_rx_buf - unmap the current RX buffer on an SGE Free List
  443. * @adapter: the adapter
  444. * @fl: the SGE Free List
  445. *
  446. * Unmap the current buffer on an SGE Free List RX queue. The
  447. * buffer must be made inaccessible to HW before calling this function.
  448. *
  449. * This is similar to @free_rx_bufs above but does not free the buffer.
  450. * Do note that the FL still loses any further access to the buffer.
  451. * This is used predominantly to "transfer ownership" of an FL buffer
  452. * to another entity (typically an skb's fragment list).
  453. */
  454. static void unmap_rx_buf(struct adapter *adapter, struct sge_fl *fl)
  455. {
  456. struct rx_sw_desc *sdesc = &fl->sdesc[fl->cidx];
  457. if (is_buf_mapped(sdesc))
  458. dma_unmap_page(adapter->pdev_dev, get_buf_addr(sdesc),
  459. get_buf_size(adapter, sdesc),
  460. PCI_DMA_FROMDEVICE);
  461. sdesc->page = NULL;
  462. if (++fl->cidx == fl->size)
  463. fl->cidx = 0;
  464. fl->avail--;
  465. }
  466. /**
  467. * ring_fl_db - righ doorbell on free list
  468. * @adapter: the adapter
  469. * @fl: the Free List whose doorbell should be rung ...
  470. *
  471. * Tell the Scatter Gather Engine that there are new free list entries
  472. * available.
  473. */
  474. static inline void ring_fl_db(struct adapter *adapter, struct sge_fl *fl)
  475. {
  476. u32 val = adapter->params.arch.sge_fl_db;
  477. /* The SGE keeps track of its Producer and Consumer Indices in terms
  478. * of Egress Queue Units so we can only tell it about integral numbers
  479. * of multiples of Free List Entries per Egress Queue Units ...
  480. */
  481. if (fl->pend_cred >= FL_PER_EQ_UNIT) {
  482. if (is_t4(adapter->params.chip))
  483. val |= PIDX_V(fl->pend_cred / FL_PER_EQ_UNIT);
  484. else
  485. val |= PIDX_T5_V(fl->pend_cred / FL_PER_EQ_UNIT);
  486. /* Make sure all memory writes to the Free List queue are
  487. * committed before we tell the hardware about them.
  488. */
  489. wmb();
  490. /* If we don't have access to the new User Doorbell (T5+), use
  491. * the old doorbell mechanism; otherwise use the new BAR2
  492. * mechanism.
  493. */
  494. if (unlikely(fl->bar2_addr == NULL)) {
  495. t4_write_reg(adapter,
  496. T4VF_SGE_BASE_ADDR + SGE_VF_KDOORBELL,
  497. QID_V(fl->cntxt_id) | val);
  498. } else {
  499. writel(val | QID_V(fl->bar2_qid),
  500. fl->bar2_addr + SGE_UDB_KDOORBELL);
  501. /* This Write memory Barrier will force the write to
  502. * the User Doorbell area to be flushed.
  503. */
  504. wmb();
  505. }
  506. fl->pend_cred %= FL_PER_EQ_UNIT;
  507. }
  508. }
  509. /**
  510. * set_rx_sw_desc - initialize software RX buffer descriptor
  511. * @sdesc: pointer to the softwore RX buffer descriptor
  512. * @page: pointer to the page data structure backing the RX buffer
  513. * @dma_addr: PCI DMA address (possibly with low-bit flags)
  514. */
  515. static inline void set_rx_sw_desc(struct rx_sw_desc *sdesc, struct page *page,
  516. dma_addr_t dma_addr)
  517. {
  518. sdesc->page = page;
  519. sdesc->dma_addr = dma_addr;
  520. }
  521. /*
  522. * Support for poisoning RX buffers ...
  523. */
  524. #define POISON_BUF_VAL -1
  525. static inline void poison_buf(struct page *page, size_t sz)
  526. {
  527. #if POISON_BUF_VAL >= 0
  528. memset(page_address(page), POISON_BUF_VAL, sz);
  529. #endif
  530. }
  531. /**
  532. * refill_fl - refill an SGE RX buffer ring
  533. * @adapter: the adapter
  534. * @fl: the Free List ring to refill
  535. * @n: the number of new buffers to allocate
  536. * @gfp: the gfp flags for the allocations
  537. *
  538. * (Re)populate an SGE free-buffer queue with up to @n new packet buffers,
  539. * allocated with the supplied gfp flags. The caller must assure that
  540. * @n does not exceed the queue's capacity -- i.e. (cidx == pidx) _IN
  541. * EGRESS QUEUE UNITS_ indicates an empty Free List! Returns the number
  542. * of buffers allocated. If afterwards the queue is found critically low,
  543. * mark it as starving in the bitmap of starving FLs.
  544. */
  545. static unsigned int refill_fl(struct adapter *adapter, struct sge_fl *fl,
  546. int n, gfp_t gfp)
  547. {
  548. struct sge *s = &adapter->sge;
  549. struct page *page;
  550. dma_addr_t dma_addr;
  551. unsigned int cred = fl->avail;
  552. __be64 *d = &fl->desc[fl->pidx];
  553. struct rx_sw_desc *sdesc = &fl->sdesc[fl->pidx];
  554. /*
  555. * Sanity: ensure that the result of adding n Free List buffers
  556. * won't result in wrapping the SGE's Producer Index around to
  557. * it's Consumer Index thereby indicating an empty Free List ...
  558. */
  559. BUG_ON(fl->avail + n > fl->size - FL_PER_EQ_UNIT);
  560. gfp |= __GFP_NOWARN;
  561. /*
  562. * If we support large pages, prefer large buffers and fail over to
  563. * small pages if we can't allocate large pages to satisfy the refill.
  564. * If we don't support large pages, drop directly into the small page
  565. * allocation code.
  566. */
  567. if (s->fl_pg_order == 0)
  568. goto alloc_small_pages;
  569. while (n) {
  570. page = __dev_alloc_pages(gfp, s->fl_pg_order);
  571. if (unlikely(!page)) {
  572. /*
  573. * We've failed inour attempt to allocate a "large
  574. * page". Fail over to the "small page" allocation
  575. * below.
  576. */
  577. fl->large_alloc_failed++;
  578. break;
  579. }
  580. poison_buf(page, PAGE_SIZE << s->fl_pg_order);
  581. dma_addr = dma_map_page(adapter->pdev_dev, page, 0,
  582. PAGE_SIZE << s->fl_pg_order,
  583. PCI_DMA_FROMDEVICE);
  584. if (unlikely(dma_mapping_error(adapter->pdev_dev, dma_addr))) {
  585. /*
  586. * We've run out of DMA mapping space. Free up the
  587. * buffer and return with what we've managed to put
  588. * into the free list. We don't want to fail over to
  589. * the small page allocation below in this case
  590. * because DMA mapping resources are typically
  591. * critical resources once they become scarse.
  592. */
  593. __free_pages(page, s->fl_pg_order);
  594. goto out;
  595. }
  596. dma_addr |= RX_LARGE_BUF;
  597. *d++ = cpu_to_be64(dma_addr);
  598. set_rx_sw_desc(sdesc, page, dma_addr);
  599. sdesc++;
  600. fl->avail++;
  601. if (++fl->pidx == fl->size) {
  602. fl->pidx = 0;
  603. sdesc = fl->sdesc;
  604. d = fl->desc;
  605. }
  606. n--;
  607. }
  608. alloc_small_pages:
  609. while (n--) {
  610. page = __dev_alloc_page(gfp);
  611. if (unlikely(!page)) {
  612. fl->alloc_failed++;
  613. break;
  614. }
  615. poison_buf(page, PAGE_SIZE);
  616. dma_addr = dma_map_page(adapter->pdev_dev, page, 0, PAGE_SIZE,
  617. PCI_DMA_FROMDEVICE);
  618. if (unlikely(dma_mapping_error(adapter->pdev_dev, dma_addr))) {
  619. put_page(page);
  620. break;
  621. }
  622. *d++ = cpu_to_be64(dma_addr);
  623. set_rx_sw_desc(sdesc, page, dma_addr);
  624. sdesc++;
  625. fl->avail++;
  626. if (++fl->pidx == fl->size) {
  627. fl->pidx = 0;
  628. sdesc = fl->sdesc;
  629. d = fl->desc;
  630. }
  631. }
  632. out:
  633. /*
  634. * Update our accounting state to incorporate the new Free List
  635. * buffers, tell the hardware about them and return the number of
  636. * buffers which we were able to allocate.
  637. */
  638. cred = fl->avail - cred;
  639. fl->pend_cred += cred;
  640. ring_fl_db(adapter, fl);
  641. if (unlikely(fl_starving(adapter, fl))) {
  642. smp_wmb();
  643. set_bit(fl->cntxt_id, adapter->sge.starving_fl);
  644. }
  645. return cred;
  646. }
  647. /*
  648. * Refill a Free List to its capacity or the Maximum Refill Increment,
  649. * whichever is smaller ...
  650. */
  651. static inline void __refill_fl(struct adapter *adapter, struct sge_fl *fl)
  652. {
  653. refill_fl(adapter, fl,
  654. min((unsigned int)MAX_RX_REFILL, fl_cap(fl) - fl->avail),
  655. GFP_ATOMIC);
  656. }
  657. /**
  658. * alloc_ring - allocate resources for an SGE descriptor ring
  659. * @dev: the PCI device's core device
  660. * @nelem: the number of descriptors
  661. * @hwsize: the size of each hardware descriptor
  662. * @swsize: the size of each software descriptor
  663. * @busaddrp: the physical PCI bus address of the allocated ring
  664. * @swringp: return address pointer for software ring
  665. * @stat_size: extra space in hardware ring for status information
  666. *
  667. * Allocates resources for an SGE descriptor ring, such as TX queues,
  668. * free buffer lists, response queues, etc. Each SGE ring requires
  669. * space for its hardware descriptors plus, optionally, space for software
  670. * state associated with each hardware entry (the metadata). The function
  671. * returns three values: the virtual address for the hardware ring (the
  672. * return value of the function), the PCI bus address of the hardware
  673. * ring (in *busaddrp), and the address of the software ring (in swringp).
  674. * Both the hardware and software rings are returned zeroed out.
  675. */
  676. static void *alloc_ring(struct device *dev, size_t nelem, size_t hwsize,
  677. size_t swsize, dma_addr_t *busaddrp, void *swringp,
  678. size_t stat_size)
  679. {
  680. /*
  681. * Allocate the hardware ring and PCI DMA bus address space for said.
  682. */
  683. size_t hwlen = nelem * hwsize + stat_size;
  684. void *hwring = dma_alloc_coherent(dev, hwlen, busaddrp, GFP_KERNEL);
  685. if (!hwring)
  686. return NULL;
  687. /*
  688. * If the caller wants a software ring, allocate it and return a
  689. * pointer to it in *swringp.
  690. */
  691. BUG_ON((swsize != 0) != (swringp != NULL));
  692. if (swsize) {
  693. void *swring = kcalloc(nelem, swsize, GFP_KERNEL);
  694. if (!swring) {
  695. dma_free_coherent(dev, hwlen, hwring, *busaddrp);
  696. return NULL;
  697. }
  698. *(void **)swringp = swring;
  699. }
  700. /*
  701. * Zero out the hardware ring and return its address as our function
  702. * value.
  703. */
  704. memset(hwring, 0, hwlen);
  705. return hwring;
  706. }
  707. /**
  708. * sgl_len - calculates the size of an SGL of the given capacity
  709. * @n: the number of SGL entries
  710. *
  711. * Calculates the number of flits (8-byte units) needed for a Direct
  712. * Scatter/Gather List that can hold the given number of entries.
  713. */
  714. static inline unsigned int sgl_len(unsigned int n)
  715. {
  716. /*
  717. * A Direct Scatter Gather List uses 32-bit lengths and 64-bit PCI DMA
  718. * addresses. The DSGL Work Request starts off with a 32-bit DSGL
  719. * ULPTX header, then Length0, then Address0, then, for 1 <= i <= N,
  720. * repeated sequences of { Length[i], Length[i+1], Address[i],
  721. * Address[i+1] } (this ensures that all addresses are on 64-bit
  722. * boundaries). If N is even, then Length[N+1] should be set to 0 and
  723. * Address[N+1] is omitted.
  724. *
  725. * The following calculation incorporates all of the above. It's
  726. * somewhat hard to follow but, briefly: the "+2" accounts for the
  727. * first two flits which include the DSGL header, Length0 and
  728. * Address0; the "(3*(n-1))/2" covers the main body of list entries (3
  729. * flits for every pair of the remaining N) +1 if (n-1) is odd; and
  730. * finally the "+((n-1)&1)" adds the one remaining flit needed if
  731. * (n-1) is odd ...
  732. */
  733. n--;
  734. return (3 * n) / 2 + (n & 1) + 2;
  735. }
  736. /**
  737. * flits_to_desc - returns the num of TX descriptors for the given flits
  738. * @flits: the number of flits
  739. *
  740. * Returns the number of TX descriptors needed for the supplied number
  741. * of flits.
  742. */
  743. static inline unsigned int flits_to_desc(unsigned int flits)
  744. {
  745. BUG_ON(flits > SGE_MAX_WR_LEN / sizeof(__be64));
  746. return DIV_ROUND_UP(flits, TXD_PER_EQ_UNIT);
  747. }
  748. /**
  749. * is_eth_imm - can an Ethernet packet be sent as immediate data?
  750. * @skb: the packet
  751. *
  752. * Returns whether an Ethernet packet is small enough to fit completely as
  753. * immediate data.
  754. */
  755. static inline int is_eth_imm(const struct sk_buff *skb)
  756. {
  757. /*
  758. * The VF Driver uses the FW_ETH_TX_PKT_VM_WR firmware Work Request
  759. * which does not accommodate immediate data. We could dike out all
  760. * of the support code for immediate data but that would tie our hands
  761. * too much if we ever want to enhace the firmware. It would also
  762. * create more differences between the PF and VF Drivers.
  763. */
  764. return false;
  765. }
  766. /**
  767. * calc_tx_flits - calculate the number of flits for a packet TX WR
  768. * @skb: the packet
  769. *
  770. * Returns the number of flits needed for a TX Work Request for the
  771. * given Ethernet packet, including the needed WR and CPL headers.
  772. */
  773. static inline unsigned int calc_tx_flits(const struct sk_buff *skb)
  774. {
  775. unsigned int flits;
  776. /*
  777. * If the skb is small enough, we can pump it out as a work request
  778. * with only immediate data. In that case we just have to have the
  779. * TX Packet header plus the skb data in the Work Request.
  780. */
  781. if (is_eth_imm(skb))
  782. return DIV_ROUND_UP(skb->len + sizeof(struct cpl_tx_pkt),
  783. sizeof(__be64));
  784. /*
  785. * Otherwise, we're going to have to construct a Scatter gather list
  786. * of the skb body and fragments. We also include the flits necessary
  787. * for the TX Packet Work Request and CPL. We always have a firmware
  788. * Write Header (incorporated as part of the cpl_tx_pkt_lso and
  789. * cpl_tx_pkt structures), followed by either a TX Packet Write CPL
  790. * message or, if we're doing a Large Send Offload, an LSO CPL message
  791. * with an embedded TX Packet Write CPL message.
  792. */
  793. flits = sgl_len(skb_shinfo(skb)->nr_frags + 1);
  794. if (skb_shinfo(skb)->gso_size)
  795. flits += (sizeof(struct fw_eth_tx_pkt_vm_wr) +
  796. sizeof(struct cpl_tx_pkt_lso_core) +
  797. sizeof(struct cpl_tx_pkt_core)) / sizeof(__be64);
  798. else
  799. flits += (sizeof(struct fw_eth_tx_pkt_vm_wr) +
  800. sizeof(struct cpl_tx_pkt_core)) / sizeof(__be64);
  801. return flits;
  802. }
  803. /**
  804. * write_sgl - populate a Scatter/Gather List for a packet
  805. * @skb: the packet
  806. * @tq: the TX queue we are writing into
  807. * @sgl: starting location for writing the SGL
  808. * @end: points right after the end of the SGL
  809. * @start: start offset into skb main-body data to include in the SGL
  810. * @addr: the list of DMA bus addresses for the SGL elements
  811. *
  812. * Generates a Scatter/Gather List for the buffers that make up a packet.
  813. * The caller must provide adequate space for the SGL that will be written.
  814. * The SGL includes all of the packet's page fragments and the data in its
  815. * main body except for the first @start bytes. @pos must be 16-byte
  816. * aligned and within a TX descriptor with available space. @end points
  817. * write after the end of the SGL but does not account for any potential
  818. * wrap around, i.e., @end > @tq->stat.
  819. */
  820. static void write_sgl(const struct sk_buff *skb, struct sge_txq *tq,
  821. struct ulptx_sgl *sgl, u64 *end, unsigned int start,
  822. const dma_addr_t *addr)
  823. {
  824. unsigned int i, len;
  825. struct ulptx_sge_pair *to;
  826. const struct skb_shared_info *si = skb_shinfo(skb);
  827. unsigned int nfrags = si->nr_frags;
  828. struct ulptx_sge_pair buf[MAX_SKB_FRAGS / 2 + 1];
  829. len = skb_headlen(skb) - start;
  830. if (likely(len)) {
  831. sgl->len0 = htonl(len);
  832. sgl->addr0 = cpu_to_be64(addr[0] + start);
  833. nfrags++;
  834. } else {
  835. sgl->len0 = htonl(skb_frag_size(&si->frags[0]));
  836. sgl->addr0 = cpu_to_be64(addr[1]);
  837. }
  838. sgl->cmd_nsge = htonl(ULPTX_CMD_V(ULP_TX_SC_DSGL) |
  839. ULPTX_NSGE_V(nfrags));
  840. if (likely(--nfrags == 0))
  841. return;
  842. /*
  843. * Most of the complexity below deals with the possibility we hit the
  844. * end of the queue in the middle of writing the SGL. For this case
  845. * only we create the SGL in a temporary buffer and then copy it.
  846. */
  847. to = (u8 *)end > (u8 *)tq->stat ? buf : sgl->sge;
  848. for (i = (nfrags != si->nr_frags); nfrags >= 2; nfrags -= 2, to++) {
  849. to->len[0] = cpu_to_be32(skb_frag_size(&si->frags[i]));
  850. to->len[1] = cpu_to_be32(skb_frag_size(&si->frags[++i]));
  851. to->addr[0] = cpu_to_be64(addr[i]);
  852. to->addr[1] = cpu_to_be64(addr[++i]);
  853. }
  854. if (nfrags) {
  855. to->len[0] = cpu_to_be32(skb_frag_size(&si->frags[i]));
  856. to->len[1] = cpu_to_be32(0);
  857. to->addr[0] = cpu_to_be64(addr[i + 1]);
  858. }
  859. if (unlikely((u8 *)end > (u8 *)tq->stat)) {
  860. unsigned int part0 = (u8 *)tq->stat - (u8 *)sgl->sge, part1;
  861. if (likely(part0))
  862. memcpy(sgl->sge, buf, part0);
  863. part1 = (u8 *)end - (u8 *)tq->stat;
  864. memcpy(tq->desc, (u8 *)buf + part0, part1);
  865. end = (void *)tq->desc + part1;
  866. }
  867. if ((uintptr_t)end & 8) /* 0-pad to multiple of 16 */
  868. *end = 0;
  869. }
  870. /**
  871. * check_ring_tx_db - check and potentially ring a TX queue's doorbell
  872. * @adapter: the adapter
  873. * @tq: the TX queue
  874. * @n: number of new descriptors to give to HW
  875. *
  876. * Ring the doorbel for a TX queue.
  877. */
  878. static inline void ring_tx_db(struct adapter *adapter, struct sge_txq *tq,
  879. int n)
  880. {
  881. /* Make sure that all writes to the TX Descriptors are committed
  882. * before we tell the hardware about them.
  883. */
  884. wmb();
  885. /* If we don't have access to the new User Doorbell (T5+), use the old
  886. * doorbell mechanism; otherwise use the new BAR2 mechanism.
  887. */
  888. if (unlikely(tq->bar2_addr == NULL)) {
  889. u32 val = PIDX_V(n);
  890. t4_write_reg(adapter, T4VF_SGE_BASE_ADDR + SGE_VF_KDOORBELL,
  891. QID_V(tq->cntxt_id) | val);
  892. } else {
  893. u32 val = PIDX_T5_V(n);
  894. /* T4 and later chips share the same PIDX field offset within
  895. * the doorbell, but T5 and later shrank the field in order to
  896. * gain a bit for Doorbell Priority. The field was absurdly
  897. * large in the first place (14 bits) so we just use the T5
  898. * and later limits and warn if a Queue ID is too large.
  899. */
  900. WARN_ON(val & DBPRIO_F);
  901. /* If we're only writing a single Egress Unit and the BAR2
  902. * Queue ID is 0, we can use the Write Combining Doorbell
  903. * Gather Buffer; otherwise we use the simple doorbell.
  904. */
  905. if (n == 1 && tq->bar2_qid == 0) {
  906. unsigned int index = (tq->pidx
  907. ? (tq->pidx - 1)
  908. : (tq->size - 1));
  909. __be64 *src = (__be64 *)&tq->desc[index];
  910. __be64 __iomem *dst = (__be64 __iomem *)(tq->bar2_addr +
  911. SGE_UDB_WCDOORBELL);
  912. unsigned int count = EQ_UNIT / sizeof(__be64);
  913. /* Copy the TX Descriptor in a tight loop in order to
  914. * try to get it to the adapter in a single Write
  915. * Combined transfer on the PCI-E Bus. If the Write
  916. * Combine fails (say because of an interrupt, etc.)
  917. * the hardware will simply take the last write as a
  918. * simple doorbell write with a PIDX Increment of 1
  919. * and will fetch the TX Descriptor from memory via
  920. * DMA.
  921. */
  922. while (count) {
  923. /* the (__force u64) is because the compiler
  924. * doesn't understand the endian swizzling
  925. * going on
  926. */
  927. writeq((__force u64)*src, dst);
  928. src++;
  929. dst++;
  930. count--;
  931. }
  932. } else
  933. writel(val | QID_V(tq->bar2_qid),
  934. tq->bar2_addr + SGE_UDB_KDOORBELL);
  935. /* This Write Memory Barrier will force the write to the User
  936. * Doorbell area to be flushed. This is needed to prevent
  937. * writes on different CPUs for the same queue from hitting
  938. * the adapter out of order. This is required when some Work
  939. * Requests take the Write Combine Gather Buffer path (user
  940. * doorbell area offset [SGE_UDB_WCDOORBELL..+63]) and some
  941. * take the traditional path where we simply increment the
  942. * PIDX (User Doorbell area SGE_UDB_KDOORBELL) and have the
  943. * hardware DMA read the actual Work Request.
  944. */
  945. wmb();
  946. }
  947. }
  948. /**
  949. * inline_tx_skb - inline a packet's data into TX descriptors
  950. * @skb: the packet
  951. * @tq: the TX queue where the packet will be inlined
  952. * @pos: starting position in the TX queue to inline the packet
  953. *
  954. * Inline a packet's contents directly into TX descriptors, starting at
  955. * the given position within the TX DMA ring.
  956. * Most of the complexity of this operation is dealing with wrap arounds
  957. * in the middle of the packet we want to inline.
  958. */
  959. static void inline_tx_skb(const struct sk_buff *skb, const struct sge_txq *tq,
  960. void *pos)
  961. {
  962. u64 *p;
  963. int left = (void *)tq->stat - pos;
  964. if (likely(skb->len <= left)) {
  965. if (likely(!skb->data_len))
  966. skb_copy_from_linear_data(skb, pos, skb->len);
  967. else
  968. skb_copy_bits(skb, 0, pos, skb->len);
  969. pos += skb->len;
  970. } else {
  971. skb_copy_bits(skb, 0, pos, left);
  972. skb_copy_bits(skb, left, tq->desc, skb->len - left);
  973. pos = (void *)tq->desc + (skb->len - left);
  974. }
  975. /* 0-pad to multiple of 16 */
  976. p = PTR_ALIGN(pos, 8);
  977. if ((uintptr_t)p & 8)
  978. *p = 0;
  979. }
  980. /*
  981. * Figure out what HW csum a packet wants and return the appropriate control
  982. * bits.
  983. */
  984. static u64 hwcsum(enum chip_type chip, const struct sk_buff *skb)
  985. {
  986. int csum_type;
  987. const struct iphdr *iph = ip_hdr(skb);
  988. if (iph->version == 4) {
  989. if (iph->protocol == IPPROTO_TCP)
  990. csum_type = TX_CSUM_TCPIP;
  991. else if (iph->protocol == IPPROTO_UDP)
  992. csum_type = TX_CSUM_UDPIP;
  993. else {
  994. nocsum:
  995. /*
  996. * unknown protocol, disable HW csum
  997. * and hope a bad packet is detected
  998. */
  999. return TXPKT_L4CSUM_DIS_F;
  1000. }
  1001. } else {
  1002. /*
  1003. * this doesn't work with extension headers
  1004. */
  1005. const struct ipv6hdr *ip6h = (const struct ipv6hdr *)iph;
  1006. if (ip6h->nexthdr == IPPROTO_TCP)
  1007. csum_type = TX_CSUM_TCPIP6;
  1008. else if (ip6h->nexthdr == IPPROTO_UDP)
  1009. csum_type = TX_CSUM_UDPIP6;
  1010. else
  1011. goto nocsum;
  1012. }
  1013. if (likely(csum_type >= TX_CSUM_TCPIP)) {
  1014. u64 hdr_len = TXPKT_IPHDR_LEN_V(skb_network_header_len(skb));
  1015. int eth_hdr_len = skb_network_offset(skb) - ETH_HLEN;
  1016. if (chip <= CHELSIO_T5)
  1017. hdr_len |= TXPKT_ETHHDR_LEN_V(eth_hdr_len);
  1018. else
  1019. hdr_len |= T6_TXPKT_ETHHDR_LEN_V(eth_hdr_len);
  1020. return TXPKT_CSUM_TYPE_V(csum_type) | hdr_len;
  1021. } else {
  1022. int start = skb_transport_offset(skb);
  1023. return TXPKT_CSUM_TYPE_V(csum_type) |
  1024. TXPKT_CSUM_START_V(start) |
  1025. TXPKT_CSUM_LOC_V(start + skb->csum_offset);
  1026. }
  1027. }
  1028. /*
  1029. * Stop an Ethernet TX queue and record that state change.
  1030. */
  1031. static void txq_stop(struct sge_eth_txq *txq)
  1032. {
  1033. netif_tx_stop_queue(txq->txq);
  1034. txq->q.stops++;
  1035. }
  1036. /*
  1037. * Advance our software state for a TX queue by adding n in use descriptors.
  1038. */
  1039. static inline void txq_advance(struct sge_txq *tq, unsigned int n)
  1040. {
  1041. tq->in_use += n;
  1042. tq->pidx += n;
  1043. if (tq->pidx >= tq->size)
  1044. tq->pidx -= tq->size;
  1045. }
  1046. /**
  1047. * t4vf_eth_xmit - add a packet to an Ethernet TX queue
  1048. * @skb: the packet
  1049. * @dev: the egress net device
  1050. *
  1051. * Add a packet to an SGE Ethernet TX queue. Runs with softirqs disabled.
  1052. */
  1053. int t4vf_eth_xmit(struct sk_buff *skb, struct net_device *dev)
  1054. {
  1055. u32 wr_mid;
  1056. u64 cntrl, *end;
  1057. int qidx, credits, max_pkt_len;
  1058. unsigned int flits, ndesc;
  1059. struct adapter *adapter;
  1060. struct sge_eth_txq *txq;
  1061. const struct port_info *pi;
  1062. struct fw_eth_tx_pkt_vm_wr *wr;
  1063. struct cpl_tx_pkt_core *cpl;
  1064. const struct skb_shared_info *ssi;
  1065. dma_addr_t addr[MAX_SKB_FRAGS + 1];
  1066. const size_t fw_hdr_copy_len = (sizeof(wr->ethmacdst) +
  1067. sizeof(wr->ethmacsrc) +
  1068. sizeof(wr->ethtype) +
  1069. sizeof(wr->vlantci));
  1070. /*
  1071. * The chip minimum packet length is 10 octets but the firmware
  1072. * command that we are using requires that we copy the Ethernet header
  1073. * (including the VLAN tag) into the header so we reject anything
  1074. * smaller than that ...
  1075. */
  1076. if (unlikely(skb->len < fw_hdr_copy_len))
  1077. goto out_free;
  1078. /* Discard the packet if the length is greater than mtu */
  1079. max_pkt_len = ETH_HLEN + dev->mtu;
  1080. if (skb_vlan_tag_present(skb))
  1081. max_pkt_len += VLAN_HLEN;
  1082. if (!skb_shinfo(skb)->gso_size && (unlikely(skb->len > max_pkt_len)))
  1083. goto out_free;
  1084. /*
  1085. * Figure out which TX Queue we're going to use.
  1086. */
  1087. pi = netdev_priv(dev);
  1088. adapter = pi->adapter;
  1089. qidx = skb_get_queue_mapping(skb);
  1090. BUG_ON(qidx >= pi->nqsets);
  1091. txq = &adapter->sge.ethtxq[pi->first_qset + qidx];
  1092. /*
  1093. * Take this opportunity to reclaim any TX Descriptors whose DMA
  1094. * transfers have completed.
  1095. */
  1096. reclaim_completed_tx(adapter, &txq->q, true);
  1097. /*
  1098. * Calculate the number of flits and TX Descriptors we're going to
  1099. * need along with how many TX Descriptors will be left over after
  1100. * we inject our Work Request.
  1101. */
  1102. flits = calc_tx_flits(skb);
  1103. ndesc = flits_to_desc(flits);
  1104. credits = txq_avail(&txq->q) - ndesc;
  1105. if (unlikely(credits < 0)) {
  1106. /*
  1107. * Not enough room for this packet's Work Request. Stop the
  1108. * TX Queue and return a "busy" condition. The queue will get
  1109. * started later on when the firmware informs us that space
  1110. * has opened up.
  1111. */
  1112. txq_stop(txq);
  1113. dev_err(adapter->pdev_dev,
  1114. "%s: TX ring %u full while queue awake!\n",
  1115. dev->name, qidx);
  1116. return NETDEV_TX_BUSY;
  1117. }
  1118. if (!is_eth_imm(skb) &&
  1119. unlikely(map_skb(adapter->pdev_dev, skb, addr) < 0)) {
  1120. /*
  1121. * We need to map the skb into PCI DMA space (because it can't
  1122. * be in-lined directly into the Work Request) and the mapping
  1123. * operation failed. Record the error and drop the packet.
  1124. */
  1125. txq->mapping_err++;
  1126. goto out_free;
  1127. }
  1128. wr_mid = FW_WR_LEN16_V(DIV_ROUND_UP(flits, 2));
  1129. if (unlikely(credits < ETHTXQ_STOP_THRES)) {
  1130. /*
  1131. * After we're done injecting the Work Request for this
  1132. * packet, we'll be below our "stop threshold" so stop the TX
  1133. * Queue now and schedule a request for an SGE Egress Queue
  1134. * Update message. The queue will get started later on when
  1135. * the firmware processes this Work Request and sends us an
  1136. * Egress Queue Status Update message indicating that space
  1137. * has opened up.
  1138. */
  1139. txq_stop(txq);
  1140. wr_mid |= FW_WR_EQUEQ_F | FW_WR_EQUIQ_F;
  1141. }
  1142. /*
  1143. * Start filling in our Work Request. Note that we do _not_ handle
  1144. * the WR Header wrapping around the TX Descriptor Ring. If our
  1145. * maximum header size ever exceeds one TX Descriptor, we'll need to
  1146. * do something else here.
  1147. */
  1148. BUG_ON(DIV_ROUND_UP(ETHTXQ_MAX_HDR, TXD_PER_EQ_UNIT) > 1);
  1149. wr = (void *)&txq->q.desc[txq->q.pidx];
  1150. wr->equiq_to_len16 = cpu_to_be32(wr_mid);
  1151. wr->r3[0] = cpu_to_be32(0);
  1152. wr->r3[1] = cpu_to_be32(0);
  1153. skb_copy_from_linear_data(skb, (void *)wr->ethmacdst, fw_hdr_copy_len);
  1154. end = (u64 *)wr + flits;
  1155. /*
  1156. * If this is a Large Send Offload packet we'll put in an LSO CPL
  1157. * message with an encapsulated TX Packet CPL message. Otherwise we
  1158. * just use a TX Packet CPL message.
  1159. */
  1160. ssi = skb_shinfo(skb);
  1161. if (ssi->gso_size) {
  1162. struct cpl_tx_pkt_lso_core *lso = (void *)(wr + 1);
  1163. bool v6 = (ssi->gso_type & SKB_GSO_TCPV6) != 0;
  1164. int l3hdr_len = skb_network_header_len(skb);
  1165. int eth_xtra_len = skb_network_offset(skb) - ETH_HLEN;
  1166. wr->op_immdlen =
  1167. cpu_to_be32(FW_WR_OP_V(FW_ETH_TX_PKT_VM_WR) |
  1168. FW_WR_IMMDLEN_V(sizeof(*lso) +
  1169. sizeof(*cpl)));
  1170. /*
  1171. * Fill in the LSO CPL message.
  1172. */
  1173. lso->lso_ctrl =
  1174. cpu_to_be32(LSO_OPCODE_V(CPL_TX_PKT_LSO) |
  1175. LSO_FIRST_SLICE_F |
  1176. LSO_LAST_SLICE_F |
  1177. LSO_IPV6_V(v6) |
  1178. LSO_ETHHDR_LEN_V(eth_xtra_len / 4) |
  1179. LSO_IPHDR_LEN_V(l3hdr_len / 4) |
  1180. LSO_TCPHDR_LEN_V(tcp_hdr(skb)->doff));
  1181. lso->ipid_ofst = cpu_to_be16(0);
  1182. lso->mss = cpu_to_be16(ssi->gso_size);
  1183. lso->seqno_offset = cpu_to_be32(0);
  1184. if (is_t4(adapter->params.chip))
  1185. lso->len = cpu_to_be32(skb->len);
  1186. else
  1187. lso->len = cpu_to_be32(LSO_T5_XFER_SIZE_V(skb->len));
  1188. /*
  1189. * Set up TX Packet CPL pointer, control word and perform
  1190. * accounting.
  1191. */
  1192. cpl = (void *)(lso + 1);
  1193. if (CHELSIO_CHIP_VERSION(adapter->params.chip) <= CHELSIO_T5)
  1194. cntrl = TXPKT_ETHHDR_LEN_V(eth_xtra_len);
  1195. else
  1196. cntrl = T6_TXPKT_ETHHDR_LEN_V(eth_xtra_len);
  1197. cntrl |= TXPKT_CSUM_TYPE_V(v6 ?
  1198. TX_CSUM_TCPIP6 : TX_CSUM_TCPIP) |
  1199. TXPKT_IPHDR_LEN_V(l3hdr_len);
  1200. txq->tso++;
  1201. txq->tx_cso += ssi->gso_segs;
  1202. } else {
  1203. int len;
  1204. len = is_eth_imm(skb) ? skb->len + sizeof(*cpl) : sizeof(*cpl);
  1205. wr->op_immdlen =
  1206. cpu_to_be32(FW_WR_OP_V(FW_ETH_TX_PKT_VM_WR) |
  1207. FW_WR_IMMDLEN_V(len));
  1208. /*
  1209. * Set up TX Packet CPL pointer, control word and perform
  1210. * accounting.
  1211. */
  1212. cpl = (void *)(wr + 1);
  1213. if (skb->ip_summed == CHECKSUM_PARTIAL) {
  1214. cntrl = hwcsum(adapter->params.chip, skb) |
  1215. TXPKT_IPCSUM_DIS_F;
  1216. txq->tx_cso++;
  1217. } else
  1218. cntrl = TXPKT_L4CSUM_DIS_F | TXPKT_IPCSUM_DIS_F;
  1219. }
  1220. /*
  1221. * If there's a VLAN tag present, add that to the list of things to
  1222. * do in this Work Request.
  1223. */
  1224. if (skb_vlan_tag_present(skb)) {
  1225. txq->vlan_ins++;
  1226. cntrl |= TXPKT_VLAN_VLD_F | TXPKT_VLAN_V(skb_vlan_tag_get(skb));
  1227. }
  1228. /*
  1229. * Fill in the TX Packet CPL message header.
  1230. */
  1231. cpl->ctrl0 = cpu_to_be32(TXPKT_OPCODE_V(CPL_TX_PKT_XT) |
  1232. TXPKT_INTF_V(pi->port_id) |
  1233. TXPKT_PF_V(0));
  1234. cpl->pack = cpu_to_be16(0);
  1235. cpl->len = cpu_to_be16(skb->len);
  1236. cpl->ctrl1 = cpu_to_be64(cntrl);
  1237. #ifdef T4_TRACE
  1238. T4_TRACE5(adapter->tb[txq->q.cntxt_id & 7],
  1239. "eth_xmit: ndesc %u, credits %u, pidx %u, len %u, frags %u",
  1240. ndesc, credits, txq->q.pidx, skb->len, ssi->nr_frags);
  1241. #endif
  1242. /*
  1243. * Fill in the body of the TX Packet CPL message with either in-lined
  1244. * data or a Scatter/Gather List.
  1245. */
  1246. if (is_eth_imm(skb)) {
  1247. /*
  1248. * In-line the packet's data and free the skb since we don't
  1249. * need it any longer.
  1250. */
  1251. inline_tx_skb(skb, &txq->q, cpl + 1);
  1252. dev_consume_skb_any(skb);
  1253. } else {
  1254. /*
  1255. * Write the skb's Scatter/Gather list into the TX Packet CPL
  1256. * message and retain a pointer to the skb so we can free it
  1257. * later when its DMA completes. (We store the skb pointer
  1258. * in the Software Descriptor corresponding to the last TX
  1259. * Descriptor used by the Work Request.)
  1260. *
  1261. * The retained skb will be freed when the corresponding TX
  1262. * Descriptors are reclaimed after their DMAs complete.
  1263. * However, this could take quite a while since, in general,
  1264. * the hardware is set up to be lazy about sending DMA
  1265. * completion notifications to us and we mostly perform TX
  1266. * reclaims in the transmit routine.
  1267. *
  1268. * This is good for performamce but means that we rely on new
  1269. * TX packets arriving to run the destructors of completed
  1270. * packets, which open up space in their sockets' send queues.
  1271. * Sometimes we do not get such new packets causing TX to
  1272. * stall. A single UDP transmitter is a good example of this
  1273. * situation. We have a clean up timer that periodically
  1274. * reclaims completed packets but it doesn't run often enough
  1275. * (nor do we want it to) to prevent lengthy stalls. A
  1276. * solution to this problem is to run the destructor early,
  1277. * after the packet is queued but before it's DMAd. A con is
  1278. * that we lie to socket memory accounting, but the amount of
  1279. * extra memory is reasonable (limited by the number of TX
  1280. * descriptors), the packets do actually get freed quickly by
  1281. * new packets almost always, and for protocols like TCP that
  1282. * wait for acks to really free up the data the extra memory
  1283. * is even less. On the positive side we run the destructors
  1284. * on the sending CPU rather than on a potentially different
  1285. * completing CPU, usually a good thing.
  1286. *
  1287. * Run the destructor before telling the DMA engine about the
  1288. * packet to make sure it doesn't complete and get freed
  1289. * prematurely.
  1290. */
  1291. struct ulptx_sgl *sgl = (struct ulptx_sgl *)(cpl + 1);
  1292. struct sge_txq *tq = &txq->q;
  1293. int last_desc;
  1294. /*
  1295. * If the Work Request header was an exact multiple of our TX
  1296. * Descriptor length, then it's possible that the starting SGL
  1297. * pointer lines up exactly with the end of our TX Descriptor
  1298. * ring. If that's the case, wrap around to the beginning
  1299. * here ...
  1300. */
  1301. if (unlikely((void *)sgl == (void *)tq->stat)) {
  1302. sgl = (void *)tq->desc;
  1303. end = ((void *)tq->desc + ((void *)end - (void *)tq->stat));
  1304. }
  1305. write_sgl(skb, tq, sgl, end, 0, addr);
  1306. skb_orphan(skb);
  1307. last_desc = tq->pidx + ndesc - 1;
  1308. if (last_desc >= tq->size)
  1309. last_desc -= tq->size;
  1310. tq->sdesc[last_desc].skb = skb;
  1311. tq->sdesc[last_desc].sgl = sgl;
  1312. }
  1313. /*
  1314. * Advance our internal TX Queue state, tell the hardware about
  1315. * the new TX descriptors and return success.
  1316. */
  1317. txq_advance(&txq->q, ndesc);
  1318. dev->trans_start = jiffies;
  1319. ring_tx_db(adapter, &txq->q, ndesc);
  1320. return NETDEV_TX_OK;
  1321. out_free:
  1322. /*
  1323. * An error of some sort happened. Free the TX skb and tell the
  1324. * OS that we've "dealt" with the packet ...
  1325. */
  1326. dev_kfree_skb_any(skb);
  1327. return NETDEV_TX_OK;
  1328. }
  1329. /**
  1330. * copy_frags - copy fragments from gather list into skb_shared_info
  1331. * @skb: destination skb
  1332. * @gl: source internal packet gather list
  1333. * @offset: packet start offset in first page
  1334. *
  1335. * Copy an internal packet gather list into a Linux skb_shared_info
  1336. * structure.
  1337. */
  1338. static inline void copy_frags(struct sk_buff *skb,
  1339. const struct pkt_gl *gl,
  1340. unsigned int offset)
  1341. {
  1342. int i;
  1343. /* usually there's just one frag */
  1344. __skb_fill_page_desc(skb, 0, gl->frags[0].page,
  1345. gl->frags[0].offset + offset,
  1346. gl->frags[0].size - offset);
  1347. skb_shinfo(skb)->nr_frags = gl->nfrags;
  1348. for (i = 1; i < gl->nfrags; i++)
  1349. __skb_fill_page_desc(skb, i, gl->frags[i].page,
  1350. gl->frags[i].offset,
  1351. gl->frags[i].size);
  1352. /* get a reference to the last page, we don't own it */
  1353. get_page(gl->frags[gl->nfrags - 1].page);
  1354. }
  1355. /**
  1356. * t4vf_pktgl_to_skb - build an sk_buff from a packet gather list
  1357. * @gl: the gather list
  1358. * @skb_len: size of sk_buff main body if it carries fragments
  1359. * @pull_len: amount of data to move to the sk_buff's main body
  1360. *
  1361. * Builds an sk_buff from the given packet gather list. Returns the
  1362. * sk_buff or %NULL if sk_buff allocation failed.
  1363. */
  1364. static struct sk_buff *t4vf_pktgl_to_skb(const struct pkt_gl *gl,
  1365. unsigned int skb_len,
  1366. unsigned int pull_len)
  1367. {
  1368. struct sk_buff *skb;
  1369. /*
  1370. * If the ingress packet is small enough, allocate an skb large enough
  1371. * for all of the data and copy it inline. Otherwise, allocate an skb
  1372. * with enough room to pull in the header and reference the rest of
  1373. * the data via the skb fragment list.
  1374. *
  1375. * Below we rely on RX_COPY_THRES being less than the smallest Rx
  1376. * buff! size, which is expected since buffers are at least
  1377. * PAGE_SIZEd. In this case packets up to RX_COPY_THRES have only one
  1378. * fragment.
  1379. */
  1380. if (gl->tot_len <= RX_COPY_THRES) {
  1381. /* small packets have only one fragment */
  1382. skb = alloc_skb(gl->tot_len, GFP_ATOMIC);
  1383. if (unlikely(!skb))
  1384. goto out;
  1385. __skb_put(skb, gl->tot_len);
  1386. skb_copy_to_linear_data(skb, gl->va, gl->tot_len);
  1387. } else {
  1388. skb = alloc_skb(skb_len, GFP_ATOMIC);
  1389. if (unlikely(!skb))
  1390. goto out;
  1391. __skb_put(skb, pull_len);
  1392. skb_copy_to_linear_data(skb, gl->va, pull_len);
  1393. copy_frags(skb, gl, pull_len);
  1394. skb->len = gl->tot_len;
  1395. skb->data_len = skb->len - pull_len;
  1396. skb->truesize += skb->data_len;
  1397. }
  1398. out:
  1399. return skb;
  1400. }
  1401. /**
  1402. * t4vf_pktgl_free - free a packet gather list
  1403. * @gl: the gather list
  1404. *
  1405. * Releases the pages of a packet gather list. We do not own the last
  1406. * page on the list and do not free it.
  1407. */
  1408. static void t4vf_pktgl_free(const struct pkt_gl *gl)
  1409. {
  1410. int frag;
  1411. frag = gl->nfrags - 1;
  1412. while (frag--)
  1413. put_page(gl->frags[frag].page);
  1414. }
  1415. /**
  1416. * do_gro - perform Generic Receive Offload ingress packet processing
  1417. * @rxq: ingress RX Ethernet Queue
  1418. * @gl: gather list for ingress packet
  1419. * @pkt: CPL header for last packet fragment
  1420. *
  1421. * Perform Generic Receive Offload (GRO) ingress packet processing.
  1422. * We use the standard Linux GRO interfaces for this.
  1423. */
  1424. static void do_gro(struct sge_eth_rxq *rxq, const struct pkt_gl *gl,
  1425. const struct cpl_rx_pkt *pkt)
  1426. {
  1427. struct adapter *adapter = rxq->rspq.adapter;
  1428. struct sge *s = &adapter->sge;
  1429. int ret;
  1430. struct sk_buff *skb;
  1431. skb = napi_get_frags(&rxq->rspq.napi);
  1432. if (unlikely(!skb)) {
  1433. t4vf_pktgl_free(gl);
  1434. rxq->stats.rx_drops++;
  1435. return;
  1436. }
  1437. copy_frags(skb, gl, s->pktshift);
  1438. skb->len = gl->tot_len - s->pktshift;
  1439. skb->data_len = skb->len;
  1440. skb->truesize += skb->data_len;
  1441. skb->ip_summed = CHECKSUM_UNNECESSARY;
  1442. skb_record_rx_queue(skb, rxq->rspq.idx);
  1443. if (pkt->vlan_ex) {
  1444. __vlan_hwaccel_put_tag(skb, cpu_to_be16(ETH_P_8021Q),
  1445. be16_to_cpu(pkt->vlan));
  1446. rxq->stats.vlan_ex++;
  1447. }
  1448. ret = napi_gro_frags(&rxq->rspq.napi);
  1449. if (ret == GRO_HELD)
  1450. rxq->stats.lro_pkts++;
  1451. else if (ret == GRO_MERGED || ret == GRO_MERGED_FREE)
  1452. rxq->stats.lro_merged++;
  1453. rxq->stats.pkts++;
  1454. rxq->stats.rx_cso++;
  1455. }
  1456. /**
  1457. * t4vf_ethrx_handler - process an ingress ethernet packet
  1458. * @rspq: the response queue that received the packet
  1459. * @rsp: the response queue descriptor holding the RX_PKT message
  1460. * @gl: the gather list of packet fragments
  1461. *
  1462. * Process an ingress ethernet packet and deliver it to the stack.
  1463. */
  1464. int t4vf_ethrx_handler(struct sge_rspq *rspq, const __be64 *rsp,
  1465. const struct pkt_gl *gl)
  1466. {
  1467. struct sk_buff *skb;
  1468. const struct cpl_rx_pkt *pkt = (void *)rsp;
  1469. bool csum_ok = pkt->csum_calc && !pkt->err_vec &&
  1470. (rspq->netdev->features & NETIF_F_RXCSUM);
  1471. struct sge_eth_rxq *rxq = container_of(rspq, struct sge_eth_rxq, rspq);
  1472. struct adapter *adapter = rspq->adapter;
  1473. struct sge *s = &adapter->sge;
  1474. /*
  1475. * If this is a good TCP packet and we have Generic Receive Offload
  1476. * enabled, handle the packet in the GRO path.
  1477. */
  1478. if ((pkt->l2info & cpu_to_be32(RXF_TCP_F)) &&
  1479. (rspq->netdev->features & NETIF_F_GRO) && csum_ok &&
  1480. !pkt->ip_frag) {
  1481. do_gro(rxq, gl, pkt);
  1482. return 0;
  1483. }
  1484. /*
  1485. * Convert the Packet Gather List into an skb.
  1486. */
  1487. skb = t4vf_pktgl_to_skb(gl, RX_SKB_LEN, RX_PULL_LEN);
  1488. if (unlikely(!skb)) {
  1489. t4vf_pktgl_free(gl);
  1490. rxq->stats.rx_drops++;
  1491. return 0;
  1492. }
  1493. __skb_pull(skb, s->pktshift);
  1494. skb->protocol = eth_type_trans(skb, rspq->netdev);
  1495. skb_record_rx_queue(skb, rspq->idx);
  1496. rxq->stats.pkts++;
  1497. if (csum_ok && !pkt->err_vec &&
  1498. (be32_to_cpu(pkt->l2info) & (RXF_UDP_F | RXF_TCP_F))) {
  1499. if (!pkt->ip_frag)
  1500. skb->ip_summed = CHECKSUM_UNNECESSARY;
  1501. else {
  1502. __sum16 c = (__force __sum16)pkt->csum;
  1503. skb->csum = csum_unfold(c);
  1504. skb->ip_summed = CHECKSUM_COMPLETE;
  1505. }
  1506. rxq->stats.rx_cso++;
  1507. } else
  1508. skb_checksum_none_assert(skb);
  1509. if (pkt->vlan_ex) {
  1510. rxq->stats.vlan_ex++;
  1511. __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), be16_to_cpu(pkt->vlan));
  1512. }
  1513. netif_receive_skb(skb);
  1514. return 0;
  1515. }
  1516. /**
  1517. * is_new_response - check if a response is newly written
  1518. * @rc: the response control descriptor
  1519. * @rspq: the response queue
  1520. *
  1521. * Returns true if a response descriptor contains a yet unprocessed
  1522. * response.
  1523. */
  1524. static inline bool is_new_response(const struct rsp_ctrl *rc,
  1525. const struct sge_rspq *rspq)
  1526. {
  1527. return ((rc->type_gen >> RSPD_GEN_S) & 0x1) == rspq->gen;
  1528. }
  1529. /**
  1530. * restore_rx_bufs - put back a packet's RX buffers
  1531. * @gl: the packet gather list
  1532. * @fl: the SGE Free List
  1533. * @nfrags: how many fragments in @si
  1534. *
  1535. * Called when we find out that the current packet, @si, can't be
  1536. * processed right away for some reason. This is a very rare event and
  1537. * there's no effort to make this suspension/resumption process
  1538. * particularly efficient.
  1539. *
  1540. * We implement the suspension by putting all of the RX buffers associated
  1541. * with the current packet back on the original Free List. The buffers
  1542. * have already been unmapped and are left unmapped, we mark them as
  1543. * unmapped in order to prevent further unmapping attempts. (Effectively
  1544. * this function undoes the series of @unmap_rx_buf calls which were done
  1545. * to create the current packet's gather list.) This leaves us ready to
  1546. * restart processing of the packet the next time we start processing the
  1547. * RX Queue ...
  1548. */
  1549. static void restore_rx_bufs(const struct pkt_gl *gl, struct sge_fl *fl,
  1550. int frags)
  1551. {
  1552. struct rx_sw_desc *sdesc;
  1553. while (frags--) {
  1554. if (fl->cidx == 0)
  1555. fl->cidx = fl->size - 1;
  1556. else
  1557. fl->cidx--;
  1558. sdesc = &fl->sdesc[fl->cidx];
  1559. sdesc->page = gl->frags[frags].page;
  1560. sdesc->dma_addr |= RX_UNMAPPED_BUF;
  1561. fl->avail++;
  1562. }
  1563. }
  1564. /**
  1565. * rspq_next - advance to the next entry in a response queue
  1566. * @rspq: the queue
  1567. *
  1568. * Updates the state of a response queue to advance it to the next entry.
  1569. */
  1570. static inline void rspq_next(struct sge_rspq *rspq)
  1571. {
  1572. rspq->cur_desc = (void *)rspq->cur_desc + rspq->iqe_len;
  1573. if (unlikely(++rspq->cidx == rspq->size)) {
  1574. rspq->cidx = 0;
  1575. rspq->gen ^= 1;
  1576. rspq->cur_desc = rspq->desc;
  1577. }
  1578. }
  1579. /**
  1580. * process_responses - process responses from an SGE response queue
  1581. * @rspq: the ingress response queue to process
  1582. * @budget: how many responses can be processed in this round
  1583. *
  1584. * Process responses from a Scatter Gather Engine response queue up to
  1585. * the supplied budget. Responses include received packets as well as
  1586. * control messages from firmware or hardware.
  1587. *
  1588. * Additionally choose the interrupt holdoff time for the next interrupt
  1589. * on this queue. If the system is under memory shortage use a fairly
  1590. * long delay to help recovery.
  1591. */
  1592. static int process_responses(struct sge_rspq *rspq, int budget)
  1593. {
  1594. struct sge_eth_rxq *rxq = container_of(rspq, struct sge_eth_rxq, rspq);
  1595. struct adapter *adapter = rspq->adapter;
  1596. struct sge *s = &adapter->sge;
  1597. int budget_left = budget;
  1598. while (likely(budget_left)) {
  1599. int ret, rsp_type;
  1600. const struct rsp_ctrl *rc;
  1601. rc = (void *)rspq->cur_desc + (rspq->iqe_len - sizeof(*rc));
  1602. if (!is_new_response(rc, rspq))
  1603. break;
  1604. /*
  1605. * Figure out what kind of response we've received from the
  1606. * SGE.
  1607. */
  1608. dma_rmb();
  1609. rsp_type = RSPD_TYPE_G(rc->type_gen);
  1610. if (likely(rsp_type == RSPD_TYPE_FLBUF_X)) {
  1611. struct page_frag *fp;
  1612. struct pkt_gl gl;
  1613. const struct rx_sw_desc *sdesc;
  1614. u32 bufsz, frag;
  1615. u32 len = be32_to_cpu(rc->pldbuflen_qid);
  1616. /*
  1617. * If we get a "new buffer" message from the SGE we
  1618. * need to move on to the next Free List buffer.
  1619. */
  1620. if (len & RSPD_NEWBUF_F) {
  1621. /*
  1622. * We get one "new buffer" message when we
  1623. * first start up a queue so we need to ignore
  1624. * it when our offset into the buffer is 0.
  1625. */
  1626. if (likely(rspq->offset > 0)) {
  1627. free_rx_bufs(rspq->adapter, &rxq->fl,
  1628. 1);
  1629. rspq->offset = 0;
  1630. }
  1631. len = RSPD_LEN_G(len);
  1632. }
  1633. gl.tot_len = len;
  1634. /*
  1635. * Gather packet fragments.
  1636. */
  1637. for (frag = 0, fp = gl.frags; /**/; frag++, fp++) {
  1638. BUG_ON(frag >= MAX_SKB_FRAGS);
  1639. BUG_ON(rxq->fl.avail == 0);
  1640. sdesc = &rxq->fl.sdesc[rxq->fl.cidx];
  1641. bufsz = get_buf_size(adapter, sdesc);
  1642. fp->page = sdesc->page;
  1643. fp->offset = rspq->offset;
  1644. fp->size = min(bufsz, len);
  1645. len -= fp->size;
  1646. if (!len)
  1647. break;
  1648. unmap_rx_buf(rspq->adapter, &rxq->fl);
  1649. }
  1650. gl.nfrags = frag+1;
  1651. /*
  1652. * Last buffer remains mapped so explicitly make it
  1653. * coherent for CPU access and start preloading first
  1654. * cache line ...
  1655. */
  1656. dma_sync_single_for_cpu(rspq->adapter->pdev_dev,
  1657. get_buf_addr(sdesc),
  1658. fp->size, DMA_FROM_DEVICE);
  1659. gl.va = (page_address(gl.frags[0].page) +
  1660. gl.frags[0].offset);
  1661. prefetch(gl.va);
  1662. /*
  1663. * Hand the new ingress packet to the handler for
  1664. * this Response Queue.
  1665. */
  1666. ret = rspq->handler(rspq, rspq->cur_desc, &gl);
  1667. if (likely(ret == 0))
  1668. rspq->offset += ALIGN(fp->size, s->fl_align);
  1669. else
  1670. restore_rx_bufs(&gl, &rxq->fl, frag);
  1671. } else if (likely(rsp_type == RSPD_TYPE_CPL_X)) {
  1672. ret = rspq->handler(rspq, rspq->cur_desc, NULL);
  1673. } else {
  1674. WARN_ON(rsp_type > RSPD_TYPE_CPL_X);
  1675. ret = 0;
  1676. }
  1677. if (unlikely(ret)) {
  1678. /*
  1679. * Couldn't process descriptor, back off for recovery.
  1680. * We use the SGE's last timer which has the longest
  1681. * interrupt coalescing value ...
  1682. */
  1683. const int NOMEM_TIMER_IDX = SGE_NTIMERS-1;
  1684. rspq->next_intr_params =
  1685. QINTR_TIMER_IDX_V(NOMEM_TIMER_IDX);
  1686. break;
  1687. }
  1688. rspq_next(rspq);
  1689. budget_left--;
  1690. }
  1691. /*
  1692. * If this is a Response Queue with an associated Free List and
  1693. * at least two Egress Queue units available in the Free List
  1694. * for new buffer pointers, refill the Free List.
  1695. */
  1696. if (rspq->offset >= 0 &&
  1697. rxq->fl.size - rxq->fl.avail >= 2*FL_PER_EQ_UNIT)
  1698. __refill_fl(rspq->adapter, &rxq->fl);
  1699. return budget - budget_left;
  1700. }
  1701. /**
  1702. * napi_rx_handler - the NAPI handler for RX processing
  1703. * @napi: the napi instance
  1704. * @budget: how many packets we can process in this round
  1705. *
  1706. * Handler for new data events when using NAPI. This does not need any
  1707. * locking or protection from interrupts as data interrupts are off at
  1708. * this point and other adapter interrupts do not interfere (the latter
  1709. * in not a concern at all with MSI-X as non-data interrupts then have
  1710. * a separate handler).
  1711. */
  1712. static int napi_rx_handler(struct napi_struct *napi, int budget)
  1713. {
  1714. unsigned int intr_params;
  1715. struct sge_rspq *rspq = container_of(napi, struct sge_rspq, napi);
  1716. int work_done = process_responses(rspq, budget);
  1717. u32 val;
  1718. if (likely(work_done < budget)) {
  1719. napi_complete(napi);
  1720. intr_params = rspq->next_intr_params;
  1721. rspq->next_intr_params = rspq->intr_params;
  1722. } else
  1723. intr_params = QINTR_TIMER_IDX_V(SGE_TIMER_UPD_CIDX);
  1724. if (unlikely(work_done == 0))
  1725. rspq->unhandled_irqs++;
  1726. val = CIDXINC_V(work_done) | SEINTARM_V(intr_params);
  1727. /* If we don't have access to the new User GTS (T5+), use the old
  1728. * doorbell mechanism; otherwise use the new BAR2 mechanism.
  1729. */
  1730. if (unlikely(!rspq->bar2_addr)) {
  1731. t4_write_reg(rspq->adapter,
  1732. T4VF_SGE_BASE_ADDR + SGE_VF_GTS,
  1733. val | INGRESSQID_V((u32)rspq->cntxt_id));
  1734. } else {
  1735. writel(val | INGRESSQID_V(rspq->bar2_qid),
  1736. rspq->bar2_addr + SGE_UDB_GTS);
  1737. wmb();
  1738. }
  1739. return work_done;
  1740. }
  1741. /*
  1742. * The MSI-X interrupt handler for an SGE response queue for the NAPI case
  1743. * (i.e., response queue serviced by NAPI polling).
  1744. */
  1745. irqreturn_t t4vf_sge_intr_msix(int irq, void *cookie)
  1746. {
  1747. struct sge_rspq *rspq = cookie;
  1748. napi_schedule(&rspq->napi);
  1749. return IRQ_HANDLED;
  1750. }
  1751. /*
  1752. * Process the indirect interrupt entries in the interrupt queue and kick off
  1753. * NAPI for each queue that has generated an entry.
  1754. */
  1755. static unsigned int process_intrq(struct adapter *adapter)
  1756. {
  1757. struct sge *s = &adapter->sge;
  1758. struct sge_rspq *intrq = &s->intrq;
  1759. unsigned int work_done;
  1760. u32 val;
  1761. spin_lock(&adapter->sge.intrq_lock);
  1762. for (work_done = 0; ; work_done++) {
  1763. const struct rsp_ctrl *rc;
  1764. unsigned int qid, iq_idx;
  1765. struct sge_rspq *rspq;
  1766. /*
  1767. * Grab the next response from the interrupt queue and bail
  1768. * out if it's not a new response.
  1769. */
  1770. rc = (void *)intrq->cur_desc + (intrq->iqe_len - sizeof(*rc));
  1771. if (!is_new_response(rc, intrq))
  1772. break;
  1773. /*
  1774. * If the response isn't a forwarded interrupt message issue a
  1775. * error and go on to the next response message. This should
  1776. * never happen ...
  1777. */
  1778. dma_rmb();
  1779. if (unlikely(RSPD_TYPE_G(rc->type_gen) != RSPD_TYPE_INTR_X)) {
  1780. dev_err(adapter->pdev_dev,
  1781. "Unexpected INTRQ response type %d\n",
  1782. RSPD_TYPE_G(rc->type_gen));
  1783. continue;
  1784. }
  1785. /*
  1786. * Extract the Queue ID from the interrupt message and perform
  1787. * sanity checking to make sure it really refers to one of our
  1788. * Ingress Queues which is active and matches the queue's ID.
  1789. * None of these error conditions should ever happen so we may
  1790. * want to either make them fatal and/or conditionalized under
  1791. * DEBUG.
  1792. */
  1793. qid = RSPD_QID_G(be32_to_cpu(rc->pldbuflen_qid));
  1794. iq_idx = IQ_IDX(s, qid);
  1795. if (unlikely(iq_idx >= MAX_INGQ)) {
  1796. dev_err(adapter->pdev_dev,
  1797. "Ingress QID %d out of range\n", qid);
  1798. continue;
  1799. }
  1800. rspq = s->ingr_map[iq_idx];
  1801. if (unlikely(rspq == NULL)) {
  1802. dev_err(adapter->pdev_dev,
  1803. "Ingress QID %d RSPQ=NULL\n", qid);
  1804. continue;
  1805. }
  1806. if (unlikely(rspq->abs_id != qid)) {
  1807. dev_err(adapter->pdev_dev,
  1808. "Ingress QID %d refers to RSPQ %d\n",
  1809. qid, rspq->abs_id);
  1810. continue;
  1811. }
  1812. /*
  1813. * Schedule NAPI processing on the indicated Response Queue
  1814. * and move on to the next entry in the Forwarded Interrupt
  1815. * Queue.
  1816. */
  1817. napi_schedule(&rspq->napi);
  1818. rspq_next(intrq);
  1819. }
  1820. val = CIDXINC_V(work_done) | SEINTARM_V(intrq->intr_params);
  1821. /* If we don't have access to the new User GTS (T5+), use the old
  1822. * doorbell mechanism; otherwise use the new BAR2 mechanism.
  1823. */
  1824. if (unlikely(!intrq->bar2_addr)) {
  1825. t4_write_reg(adapter, T4VF_SGE_BASE_ADDR + SGE_VF_GTS,
  1826. val | INGRESSQID_V(intrq->cntxt_id));
  1827. } else {
  1828. writel(val | INGRESSQID_V(intrq->bar2_qid),
  1829. intrq->bar2_addr + SGE_UDB_GTS);
  1830. wmb();
  1831. }
  1832. spin_unlock(&adapter->sge.intrq_lock);
  1833. return work_done;
  1834. }
  1835. /*
  1836. * The MSI interrupt handler handles data events from SGE response queues as
  1837. * well as error and other async events as they all use the same MSI vector.
  1838. */
  1839. static irqreturn_t t4vf_intr_msi(int irq, void *cookie)
  1840. {
  1841. struct adapter *adapter = cookie;
  1842. process_intrq(adapter);
  1843. return IRQ_HANDLED;
  1844. }
  1845. /**
  1846. * t4vf_intr_handler - select the top-level interrupt handler
  1847. * @adapter: the adapter
  1848. *
  1849. * Selects the top-level interrupt handler based on the type of interrupts
  1850. * (MSI-X or MSI).
  1851. */
  1852. irq_handler_t t4vf_intr_handler(struct adapter *adapter)
  1853. {
  1854. BUG_ON((adapter->flags & (USING_MSIX|USING_MSI)) == 0);
  1855. if (adapter->flags & USING_MSIX)
  1856. return t4vf_sge_intr_msix;
  1857. else
  1858. return t4vf_intr_msi;
  1859. }
  1860. /**
  1861. * sge_rx_timer_cb - perform periodic maintenance of SGE RX queues
  1862. * @data: the adapter
  1863. *
  1864. * Runs periodically from a timer to perform maintenance of SGE RX queues.
  1865. *
  1866. * a) Replenishes RX queues that have run out due to memory shortage.
  1867. * Normally new RX buffers are added when existing ones are consumed but
  1868. * when out of memory a queue can become empty. We schedule NAPI to do
  1869. * the actual refill.
  1870. */
  1871. static void sge_rx_timer_cb(unsigned long data)
  1872. {
  1873. struct adapter *adapter = (struct adapter *)data;
  1874. struct sge *s = &adapter->sge;
  1875. unsigned int i;
  1876. /*
  1877. * Scan the "Starving Free Lists" flag array looking for any Free
  1878. * Lists in need of more free buffers. If we find one and it's not
  1879. * being actively polled, then bump its "starving" counter and attempt
  1880. * to refill it. If we're successful in adding enough buffers to push
  1881. * the Free List over the starving threshold, then we can clear its
  1882. * "starving" status.
  1883. */
  1884. for (i = 0; i < ARRAY_SIZE(s->starving_fl); i++) {
  1885. unsigned long m;
  1886. for (m = s->starving_fl[i]; m; m &= m - 1) {
  1887. unsigned int id = __ffs(m) + i * BITS_PER_LONG;
  1888. struct sge_fl *fl = s->egr_map[id];
  1889. clear_bit(id, s->starving_fl);
  1890. smp_mb__after_atomic();
  1891. /*
  1892. * Since we are accessing fl without a lock there's a
  1893. * small probability of a false positive where we
  1894. * schedule napi but the FL is no longer starving.
  1895. * No biggie.
  1896. */
  1897. if (fl_starving(adapter, fl)) {
  1898. struct sge_eth_rxq *rxq;
  1899. rxq = container_of(fl, struct sge_eth_rxq, fl);
  1900. if (napi_reschedule(&rxq->rspq.napi))
  1901. fl->starving++;
  1902. else
  1903. set_bit(id, s->starving_fl);
  1904. }
  1905. }
  1906. }
  1907. /*
  1908. * Reschedule the next scan for starving Free Lists ...
  1909. */
  1910. mod_timer(&s->rx_timer, jiffies + RX_QCHECK_PERIOD);
  1911. }
  1912. /**
  1913. * sge_tx_timer_cb - perform periodic maintenance of SGE Tx queues
  1914. * @data: the adapter
  1915. *
  1916. * Runs periodically from a timer to perform maintenance of SGE TX queues.
  1917. *
  1918. * b) Reclaims completed Tx packets for the Ethernet queues. Normally
  1919. * packets are cleaned up by new Tx packets, this timer cleans up packets
  1920. * when no new packets are being submitted. This is essential for pktgen,
  1921. * at least.
  1922. */
  1923. static void sge_tx_timer_cb(unsigned long data)
  1924. {
  1925. struct adapter *adapter = (struct adapter *)data;
  1926. struct sge *s = &adapter->sge;
  1927. unsigned int i, budget;
  1928. budget = MAX_TIMER_TX_RECLAIM;
  1929. i = s->ethtxq_rover;
  1930. do {
  1931. struct sge_eth_txq *txq = &s->ethtxq[i];
  1932. if (reclaimable(&txq->q) && __netif_tx_trylock(txq->txq)) {
  1933. int avail = reclaimable(&txq->q);
  1934. if (avail > budget)
  1935. avail = budget;
  1936. free_tx_desc(adapter, &txq->q, avail, true);
  1937. txq->q.in_use -= avail;
  1938. __netif_tx_unlock(txq->txq);
  1939. budget -= avail;
  1940. if (!budget)
  1941. break;
  1942. }
  1943. i++;
  1944. if (i >= s->ethqsets)
  1945. i = 0;
  1946. } while (i != s->ethtxq_rover);
  1947. s->ethtxq_rover = i;
  1948. /*
  1949. * If we found too many reclaimable packets schedule a timer in the
  1950. * near future to continue where we left off. Otherwise the next timer
  1951. * will be at its normal interval.
  1952. */
  1953. mod_timer(&s->tx_timer, jiffies + (budget ? TX_QCHECK_PERIOD : 2));
  1954. }
  1955. /**
  1956. * bar2_address - return the BAR2 address for an SGE Queue's Registers
  1957. * @adapter: the adapter
  1958. * @qid: the SGE Queue ID
  1959. * @qtype: the SGE Queue Type (Egress or Ingress)
  1960. * @pbar2_qid: BAR2 Queue ID or 0 for Queue ID inferred SGE Queues
  1961. *
  1962. * Returns the BAR2 address for the SGE Queue Registers associated with
  1963. * @qid. If BAR2 SGE Registers aren't available, returns NULL. Also
  1964. * returns the BAR2 Queue ID to be used with writes to the BAR2 SGE
  1965. * Queue Registers. If the BAR2 Queue ID is 0, then "Inferred Queue ID"
  1966. * Registers are supported (e.g. the Write Combining Doorbell Buffer).
  1967. */
  1968. static void __iomem *bar2_address(struct adapter *adapter,
  1969. unsigned int qid,
  1970. enum t4_bar2_qtype qtype,
  1971. unsigned int *pbar2_qid)
  1972. {
  1973. u64 bar2_qoffset;
  1974. int ret;
  1975. ret = t4vf_bar2_sge_qregs(adapter, qid, qtype,
  1976. &bar2_qoffset, pbar2_qid);
  1977. if (ret)
  1978. return NULL;
  1979. return adapter->bar2 + bar2_qoffset;
  1980. }
  1981. /**
  1982. * t4vf_sge_alloc_rxq - allocate an SGE RX Queue
  1983. * @adapter: the adapter
  1984. * @rspq: pointer to to the new rxq's Response Queue to be filled in
  1985. * @iqasynch: if 0, a normal rspq; if 1, an asynchronous event queue
  1986. * @dev: the network device associated with the new rspq
  1987. * @intr_dest: MSI-X vector index (overriden in MSI mode)
  1988. * @fl: pointer to the new rxq's Free List to be filled in
  1989. * @hnd: the interrupt handler to invoke for the rspq
  1990. */
  1991. int t4vf_sge_alloc_rxq(struct adapter *adapter, struct sge_rspq *rspq,
  1992. bool iqasynch, struct net_device *dev,
  1993. int intr_dest,
  1994. struct sge_fl *fl, rspq_handler_t hnd)
  1995. {
  1996. struct sge *s = &adapter->sge;
  1997. struct port_info *pi = netdev_priv(dev);
  1998. struct fw_iq_cmd cmd, rpl;
  1999. int ret, iqandst, flsz = 0;
  2000. /*
  2001. * If we're using MSI interrupts and we're not initializing the
  2002. * Forwarded Interrupt Queue itself, then set up this queue for
  2003. * indirect interrupts to the Forwarded Interrupt Queue. Obviously
  2004. * the Forwarded Interrupt Queue must be set up before any other
  2005. * ingress queue ...
  2006. */
  2007. if ((adapter->flags & USING_MSI) && rspq != &adapter->sge.intrq) {
  2008. iqandst = SGE_INTRDST_IQ;
  2009. intr_dest = adapter->sge.intrq.abs_id;
  2010. } else
  2011. iqandst = SGE_INTRDST_PCI;
  2012. /*
  2013. * Allocate the hardware ring for the Response Queue. The size needs
  2014. * to be a multiple of 16 which includes the mandatory status entry
  2015. * (regardless of whether the Status Page capabilities are enabled or
  2016. * not).
  2017. */
  2018. rspq->size = roundup(rspq->size, 16);
  2019. rspq->desc = alloc_ring(adapter->pdev_dev, rspq->size, rspq->iqe_len,
  2020. 0, &rspq->phys_addr, NULL, 0);
  2021. if (!rspq->desc)
  2022. return -ENOMEM;
  2023. /*
  2024. * Fill in the Ingress Queue Command. Note: Ideally this code would
  2025. * be in t4vf_hw.c but there are so many parameters and dependencies
  2026. * on our Linux SGE state that we would end up having to pass tons of
  2027. * parameters. We'll have to think about how this might be migrated
  2028. * into OS-independent common code ...
  2029. */
  2030. memset(&cmd, 0, sizeof(cmd));
  2031. cmd.op_to_vfn = cpu_to_be32(FW_CMD_OP_V(FW_IQ_CMD) |
  2032. FW_CMD_REQUEST_F |
  2033. FW_CMD_WRITE_F |
  2034. FW_CMD_EXEC_F);
  2035. cmd.alloc_to_len16 = cpu_to_be32(FW_IQ_CMD_ALLOC_F |
  2036. FW_IQ_CMD_IQSTART_F |
  2037. FW_LEN16(cmd));
  2038. cmd.type_to_iqandstindex =
  2039. cpu_to_be32(FW_IQ_CMD_TYPE_V(FW_IQ_TYPE_FL_INT_CAP) |
  2040. FW_IQ_CMD_IQASYNCH_V(iqasynch) |
  2041. FW_IQ_CMD_VIID_V(pi->viid) |
  2042. FW_IQ_CMD_IQANDST_V(iqandst) |
  2043. FW_IQ_CMD_IQANUS_V(1) |
  2044. FW_IQ_CMD_IQANUD_V(SGE_UPDATEDEL_INTR) |
  2045. FW_IQ_CMD_IQANDSTINDEX_V(intr_dest));
  2046. cmd.iqdroprss_to_iqesize =
  2047. cpu_to_be16(FW_IQ_CMD_IQPCIECH_V(pi->port_id) |
  2048. FW_IQ_CMD_IQGTSMODE_F |
  2049. FW_IQ_CMD_IQINTCNTTHRESH_V(rspq->pktcnt_idx) |
  2050. FW_IQ_CMD_IQESIZE_V(ilog2(rspq->iqe_len) - 4));
  2051. cmd.iqsize = cpu_to_be16(rspq->size);
  2052. cmd.iqaddr = cpu_to_be64(rspq->phys_addr);
  2053. if (fl) {
  2054. enum chip_type chip =
  2055. CHELSIO_CHIP_VERSION(adapter->params.chip);
  2056. /*
  2057. * Allocate the ring for the hardware free list (with space
  2058. * for its status page) along with the associated software
  2059. * descriptor ring. The free list size needs to be a multiple
  2060. * of the Egress Queue Unit and at least 2 Egress Units larger
  2061. * than the SGE's Egress Congrestion Threshold
  2062. * (fl_starve_thres - 1).
  2063. */
  2064. if (fl->size < s->fl_starve_thres - 1 + 2 * FL_PER_EQ_UNIT)
  2065. fl->size = s->fl_starve_thres - 1 + 2 * FL_PER_EQ_UNIT;
  2066. fl->size = roundup(fl->size, FL_PER_EQ_UNIT);
  2067. fl->desc = alloc_ring(adapter->pdev_dev, fl->size,
  2068. sizeof(__be64), sizeof(struct rx_sw_desc),
  2069. &fl->addr, &fl->sdesc, s->stat_len);
  2070. if (!fl->desc) {
  2071. ret = -ENOMEM;
  2072. goto err;
  2073. }
  2074. /*
  2075. * Calculate the size of the hardware free list ring plus
  2076. * Status Page (which the SGE will place after the end of the
  2077. * free list ring) in Egress Queue Units.
  2078. */
  2079. flsz = (fl->size / FL_PER_EQ_UNIT +
  2080. s->stat_len / EQ_UNIT);
  2081. /*
  2082. * Fill in all the relevant firmware Ingress Queue Command
  2083. * fields for the free list.
  2084. */
  2085. cmd.iqns_to_fl0congen =
  2086. cpu_to_be32(
  2087. FW_IQ_CMD_FL0HOSTFCMODE_V(SGE_HOSTFCMODE_NONE) |
  2088. FW_IQ_CMD_FL0PACKEN_F |
  2089. FW_IQ_CMD_FL0PADEN_F);
  2090. cmd.fl0dcaen_to_fl0cidxfthresh =
  2091. cpu_to_be16(
  2092. FW_IQ_CMD_FL0FBMIN_V(SGE_FETCHBURSTMIN_64B) |
  2093. FW_IQ_CMD_FL0FBMAX_V((chip <= CHELSIO_T5) ?
  2094. FETCHBURSTMAX_512B_X :
  2095. FETCHBURSTMAX_256B_X));
  2096. cmd.fl0size = cpu_to_be16(flsz);
  2097. cmd.fl0addr = cpu_to_be64(fl->addr);
  2098. }
  2099. /*
  2100. * Issue the firmware Ingress Queue Command and extract the results if
  2101. * it completes successfully.
  2102. */
  2103. ret = t4vf_wr_mbox(adapter, &cmd, sizeof(cmd), &rpl);
  2104. if (ret)
  2105. goto err;
  2106. netif_napi_add(dev, &rspq->napi, napi_rx_handler, 64);
  2107. rspq->cur_desc = rspq->desc;
  2108. rspq->cidx = 0;
  2109. rspq->gen = 1;
  2110. rspq->next_intr_params = rspq->intr_params;
  2111. rspq->cntxt_id = be16_to_cpu(rpl.iqid);
  2112. rspq->bar2_addr = bar2_address(adapter,
  2113. rspq->cntxt_id,
  2114. T4_BAR2_QTYPE_INGRESS,
  2115. &rspq->bar2_qid);
  2116. rspq->abs_id = be16_to_cpu(rpl.physiqid);
  2117. rspq->size--; /* subtract status entry */
  2118. rspq->adapter = adapter;
  2119. rspq->netdev = dev;
  2120. rspq->handler = hnd;
  2121. /* set offset to -1 to distinguish ingress queues without FL */
  2122. rspq->offset = fl ? 0 : -1;
  2123. if (fl) {
  2124. fl->cntxt_id = be16_to_cpu(rpl.fl0id);
  2125. fl->avail = 0;
  2126. fl->pend_cred = 0;
  2127. fl->pidx = 0;
  2128. fl->cidx = 0;
  2129. fl->alloc_failed = 0;
  2130. fl->large_alloc_failed = 0;
  2131. fl->starving = 0;
  2132. /* Note, we must initialize the BAR2 Free List User Doorbell
  2133. * information before refilling the Free List!
  2134. */
  2135. fl->bar2_addr = bar2_address(adapter,
  2136. fl->cntxt_id,
  2137. T4_BAR2_QTYPE_EGRESS,
  2138. &fl->bar2_qid);
  2139. refill_fl(adapter, fl, fl_cap(fl), GFP_KERNEL);
  2140. }
  2141. return 0;
  2142. err:
  2143. /*
  2144. * An error occurred. Clean up our partial allocation state and
  2145. * return the error.
  2146. */
  2147. if (rspq->desc) {
  2148. dma_free_coherent(adapter->pdev_dev, rspq->size * rspq->iqe_len,
  2149. rspq->desc, rspq->phys_addr);
  2150. rspq->desc = NULL;
  2151. }
  2152. if (fl && fl->desc) {
  2153. kfree(fl->sdesc);
  2154. fl->sdesc = NULL;
  2155. dma_free_coherent(adapter->pdev_dev, flsz * EQ_UNIT,
  2156. fl->desc, fl->addr);
  2157. fl->desc = NULL;
  2158. }
  2159. return ret;
  2160. }
  2161. /**
  2162. * t4vf_sge_alloc_eth_txq - allocate an SGE Ethernet TX Queue
  2163. * @adapter: the adapter
  2164. * @txq: pointer to the new txq to be filled in
  2165. * @devq: the network TX queue associated with the new txq
  2166. * @iqid: the relative ingress queue ID to which events relating to
  2167. * the new txq should be directed
  2168. */
  2169. int t4vf_sge_alloc_eth_txq(struct adapter *adapter, struct sge_eth_txq *txq,
  2170. struct net_device *dev, struct netdev_queue *devq,
  2171. unsigned int iqid)
  2172. {
  2173. struct sge *s = &adapter->sge;
  2174. int ret, nentries;
  2175. struct fw_eq_eth_cmd cmd, rpl;
  2176. struct port_info *pi = netdev_priv(dev);
  2177. /*
  2178. * Calculate the size of the hardware TX Queue (including the Status
  2179. * Page on the end of the TX Queue) in units of TX Descriptors.
  2180. */
  2181. nentries = txq->q.size + s->stat_len / sizeof(struct tx_desc);
  2182. /*
  2183. * Allocate the hardware ring for the TX ring (with space for its
  2184. * status page) along with the associated software descriptor ring.
  2185. */
  2186. txq->q.desc = alloc_ring(adapter->pdev_dev, txq->q.size,
  2187. sizeof(struct tx_desc),
  2188. sizeof(struct tx_sw_desc),
  2189. &txq->q.phys_addr, &txq->q.sdesc, s->stat_len);
  2190. if (!txq->q.desc)
  2191. return -ENOMEM;
  2192. /*
  2193. * Fill in the Egress Queue Command. Note: As with the direct use of
  2194. * the firmware Ingress Queue COmmand above in our RXQ allocation
  2195. * routine, ideally, this code would be in t4vf_hw.c. Again, we'll
  2196. * have to see if there's some reasonable way to parameterize it
  2197. * into the common code ...
  2198. */
  2199. memset(&cmd, 0, sizeof(cmd));
  2200. cmd.op_to_vfn = cpu_to_be32(FW_CMD_OP_V(FW_EQ_ETH_CMD) |
  2201. FW_CMD_REQUEST_F |
  2202. FW_CMD_WRITE_F |
  2203. FW_CMD_EXEC_F);
  2204. cmd.alloc_to_len16 = cpu_to_be32(FW_EQ_ETH_CMD_ALLOC_F |
  2205. FW_EQ_ETH_CMD_EQSTART_F |
  2206. FW_LEN16(cmd));
  2207. cmd.viid_pkd = cpu_to_be32(FW_EQ_ETH_CMD_AUTOEQUEQE_F |
  2208. FW_EQ_ETH_CMD_VIID_V(pi->viid));
  2209. cmd.fetchszm_to_iqid =
  2210. cpu_to_be32(FW_EQ_ETH_CMD_HOSTFCMODE_V(SGE_HOSTFCMODE_STPG) |
  2211. FW_EQ_ETH_CMD_PCIECHN_V(pi->port_id) |
  2212. FW_EQ_ETH_CMD_IQID_V(iqid));
  2213. cmd.dcaen_to_eqsize =
  2214. cpu_to_be32(FW_EQ_ETH_CMD_FBMIN_V(SGE_FETCHBURSTMIN_64B) |
  2215. FW_EQ_ETH_CMD_FBMAX_V(SGE_FETCHBURSTMAX_512B) |
  2216. FW_EQ_ETH_CMD_CIDXFTHRESH_V(
  2217. SGE_CIDXFLUSHTHRESH_32) |
  2218. FW_EQ_ETH_CMD_EQSIZE_V(nentries));
  2219. cmd.eqaddr = cpu_to_be64(txq->q.phys_addr);
  2220. /*
  2221. * Issue the firmware Egress Queue Command and extract the results if
  2222. * it completes successfully.
  2223. */
  2224. ret = t4vf_wr_mbox(adapter, &cmd, sizeof(cmd), &rpl);
  2225. if (ret) {
  2226. /*
  2227. * The girmware Ingress Queue Command failed for some reason.
  2228. * Free up our partial allocation state and return the error.
  2229. */
  2230. kfree(txq->q.sdesc);
  2231. txq->q.sdesc = NULL;
  2232. dma_free_coherent(adapter->pdev_dev,
  2233. nentries * sizeof(struct tx_desc),
  2234. txq->q.desc, txq->q.phys_addr);
  2235. txq->q.desc = NULL;
  2236. return ret;
  2237. }
  2238. txq->q.in_use = 0;
  2239. txq->q.cidx = 0;
  2240. txq->q.pidx = 0;
  2241. txq->q.stat = (void *)&txq->q.desc[txq->q.size];
  2242. txq->q.cntxt_id = FW_EQ_ETH_CMD_EQID_G(be32_to_cpu(rpl.eqid_pkd));
  2243. txq->q.bar2_addr = bar2_address(adapter,
  2244. txq->q.cntxt_id,
  2245. T4_BAR2_QTYPE_EGRESS,
  2246. &txq->q.bar2_qid);
  2247. txq->q.abs_id =
  2248. FW_EQ_ETH_CMD_PHYSEQID_G(be32_to_cpu(rpl.physeqid_pkd));
  2249. txq->txq = devq;
  2250. txq->tso = 0;
  2251. txq->tx_cso = 0;
  2252. txq->vlan_ins = 0;
  2253. txq->q.stops = 0;
  2254. txq->q.restarts = 0;
  2255. txq->mapping_err = 0;
  2256. return 0;
  2257. }
  2258. /*
  2259. * Free the DMA map resources associated with a TX queue.
  2260. */
  2261. static void free_txq(struct adapter *adapter, struct sge_txq *tq)
  2262. {
  2263. struct sge *s = &adapter->sge;
  2264. dma_free_coherent(adapter->pdev_dev,
  2265. tq->size * sizeof(*tq->desc) + s->stat_len,
  2266. tq->desc, tq->phys_addr);
  2267. tq->cntxt_id = 0;
  2268. tq->sdesc = NULL;
  2269. tq->desc = NULL;
  2270. }
  2271. /*
  2272. * Free the resources associated with a response queue (possibly including a
  2273. * free list).
  2274. */
  2275. static void free_rspq_fl(struct adapter *adapter, struct sge_rspq *rspq,
  2276. struct sge_fl *fl)
  2277. {
  2278. struct sge *s = &adapter->sge;
  2279. unsigned int flid = fl ? fl->cntxt_id : 0xffff;
  2280. t4vf_iq_free(adapter, FW_IQ_TYPE_FL_INT_CAP,
  2281. rspq->cntxt_id, flid, 0xffff);
  2282. dma_free_coherent(adapter->pdev_dev, (rspq->size + 1) * rspq->iqe_len,
  2283. rspq->desc, rspq->phys_addr);
  2284. netif_napi_del(&rspq->napi);
  2285. rspq->netdev = NULL;
  2286. rspq->cntxt_id = 0;
  2287. rspq->abs_id = 0;
  2288. rspq->desc = NULL;
  2289. if (fl) {
  2290. free_rx_bufs(adapter, fl, fl->avail);
  2291. dma_free_coherent(adapter->pdev_dev,
  2292. fl->size * sizeof(*fl->desc) + s->stat_len,
  2293. fl->desc, fl->addr);
  2294. kfree(fl->sdesc);
  2295. fl->sdesc = NULL;
  2296. fl->cntxt_id = 0;
  2297. fl->desc = NULL;
  2298. }
  2299. }
  2300. /**
  2301. * t4vf_free_sge_resources - free SGE resources
  2302. * @adapter: the adapter
  2303. *
  2304. * Frees resources used by the SGE queue sets.
  2305. */
  2306. void t4vf_free_sge_resources(struct adapter *adapter)
  2307. {
  2308. struct sge *s = &adapter->sge;
  2309. struct sge_eth_rxq *rxq = s->ethrxq;
  2310. struct sge_eth_txq *txq = s->ethtxq;
  2311. struct sge_rspq *evtq = &s->fw_evtq;
  2312. struct sge_rspq *intrq = &s->intrq;
  2313. int qs;
  2314. for (qs = 0; qs < adapter->sge.ethqsets; qs++, rxq++, txq++) {
  2315. if (rxq->rspq.desc)
  2316. free_rspq_fl(adapter, &rxq->rspq, &rxq->fl);
  2317. if (txq->q.desc) {
  2318. t4vf_eth_eq_free(adapter, txq->q.cntxt_id);
  2319. free_tx_desc(adapter, &txq->q, txq->q.in_use, true);
  2320. kfree(txq->q.sdesc);
  2321. free_txq(adapter, &txq->q);
  2322. }
  2323. }
  2324. if (evtq->desc)
  2325. free_rspq_fl(adapter, evtq, NULL);
  2326. if (intrq->desc)
  2327. free_rspq_fl(adapter, intrq, NULL);
  2328. }
  2329. /**
  2330. * t4vf_sge_start - enable SGE operation
  2331. * @adapter: the adapter
  2332. *
  2333. * Start tasklets and timers associated with the DMA engine.
  2334. */
  2335. void t4vf_sge_start(struct adapter *adapter)
  2336. {
  2337. adapter->sge.ethtxq_rover = 0;
  2338. mod_timer(&adapter->sge.rx_timer, jiffies + RX_QCHECK_PERIOD);
  2339. mod_timer(&adapter->sge.tx_timer, jiffies + TX_QCHECK_PERIOD);
  2340. }
  2341. /**
  2342. * t4vf_sge_stop - disable SGE operation
  2343. * @adapter: the adapter
  2344. *
  2345. * Stop tasklets and timers associated with the DMA engine. Note that
  2346. * this is effective only if measures have been taken to disable any HW
  2347. * events that may restart them.
  2348. */
  2349. void t4vf_sge_stop(struct adapter *adapter)
  2350. {
  2351. struct sge *s = &adapter->sge;
  2352. if (s->rx_timer.function)
  2353. del_timer_sync(&s->rx_timer);
  2354. if (s->tx_timer.function)
  2355. del_timer_sync(&s->tx_timer);
  2356. }
  2357. /**
  2358. * t4vf_sge_init - initialize SGE
  2359. * @adapter: the adapter
  2360. *
  2361. * Performs SGE initialization needed every time after a chip reset.
  2362. * We do not initialize any of the queue sets here, instead the driver
  2363. * top-level must request those individually. We also do not enable DMA
  2364. * here, that should be done after the queues have been set up.
  2365. */
  2366. int t4vf_sge_init(struct adapter *adapter)
  2367. {
  2368. struct sge_params *sge_params = &adapter->params.sge;
  2369. u32 fl_small_pg = sge_params->sge_fl_buffer_size[0];
  2370. u32 fl_large_pg = sge_params->sge_fl_buffer_size[1];
  2371. struct sge *s = &adapter->sge;
  2372. unsigned int ingpadboundary, ingpackboundary;
  2373. /*
  2374. * Start by vetting the basic SGE parameters which have been set up by
  2375. * the Physical Function Driver. Ideally we should be able to deal
  2376. * with _any_ configuration. Practice is different ...
  2377. */
  2378. /* We only bother using the Large Page logic if the Large Page Buffer
  2379. * is larger than our Page Size Buffer.
  2380. */
  2381. if (fl_large_pg <= fl_small_pg)
  2382. fl_large_pg = 0;
  2383. /* The Page Size Buffer must be exactly equal to our Page Size and the
  2384. * Large Page Size Buffer should be 0 (per above) or a power of 2.
  2385. */
  2386. if (fl_small_pg != PAGE_SIZE ||
  2387. (fl_large_pg & (fl_large_pg - 1)) != 0) {
  2388. dev_err(adapter->pdev_dev, "bad SGE FL buffer sizes [%d, %d]\n",
  2389. fl_small_pg, fl_large_pg);
  2390. return -EINVAL;
  2391. }
  2392. if ((sge_params->sge_control & RXPKTCPLMODE_F) == 0) {
  2393. dev_err(adapter->pdev_dev, "bad SGE CPL MODE\n");
  2394. return -EINVAL;
  2395. }
  2396. /*
  2397. * Now translate the adapter parameters into our internal forms.
  2398. */
  2399. if (fl_large_pg)
  2400. s->fl_pg_order = ilog2(fl_large_pg) - PAGE_SHIFT;
  2401. s->stat_len = ((sge_params->sge_control & EGRSTATUSPAGESIZE_F)
  2402. ? 128 : 64);
  2403. s->pktshift = PKTSHIFT_G(sge_params->sge_control);
  2404. /* T4 uses a single control field to specify both the PCIe Padding and
  2405. * Packing Boundary. T5 introduced the ability to specify these
  2406. * separately. The actual Ingress Packet Data alignment boundary
  2407. * within Packed Buffer Mode is the maximum of these two
  2408. * specifications. (Note that it makes no real practical sense to
  2409. * have the Pading Boudary be larger than the Packing Boundary but you
  2410. * could set the chip up that way and, in fact, legacy T4 code would
  2411. * end doing this because it would initialize the Padding Boundary and
  2412. * leave the Packing Boundary initialized to 0 (16 bytes).)
  2413. */
  2414. ingpadboundary = 1 << (INGPADBOUNDARY_G(sge_params->sge_control) +
  2415. INGPADBOUNDARY_SHIFT_X);
  2416. if (is_t4(adapter->params.chip)) {
  2417. s->fl_align = ingpadboundary;
  2418. } else {
  2419. /* T5 has a different interpretation of one of the PCIe Packing
  2420. * Boundary values.
  2421. */
  2422. ingpackboundary = INGPACKBOUNDARY_G(sge_params->sge_control2);
  2423. if (ingpackboundary == INGPACKBOUNDARY_16B_X)
  2424. ingpackboundary = 16;
  2425. else
  2426. ingpackboundary = 1 << (ingpackboundary +
  2427. INGPACKBOUNDARY_SHIFT_X);
  2428. s->fl_align = max(ingpadboundary, ingpackboundary);
  2429. }
  2430. /* A FL with <= fl_starve_thres buffers is starving and a periodic
  2431. * timer will attempt to refill it. This needs to be larger than the
  2432. * SGE's Egress Congestion Threshold. If it isn't, then we can get
  2433. * stuck waiting for new packets while the SGE is waiting for us to
  2434. * give it more Free List entries. (Note that the SGE's Egress
  2435. * Congestion Threshold is in units of 2 Free List pointers.)
  2436. */
  2437. switch (CHELSIO_CHIP_VERSION(adapter->params.chip)) {
  2438. case CHELSIO_T4:
  2439. s->fl_starve_thres =
  2440. EGRTHRESHOLD_G(sge_params->sge_congestion_control);
  2441. break;
  2442. case CHELSIO_T5:
  2443. s->fl_starve_thres =
  2444. EGRTHRESHOLDPACKING_G(sge_params->sge_congestion_control);
  2445. break;
  2446. case CHELSIO_T6:
  2447. default:
  2448. s->fl_starve_thres =
  2449. T6_EGRTHRESHOLDPACKING_G(sge_params->sge_congestion_control);
  2450. break;
  2451. }
  2452. s->fl_starve_thres = s->fl_starve_thres * 2 + 1;
  2453. /*
  2454. * Set up tasklet timers.
  2455. */
  2456. setup_timer(&s->rx_timer, sge_rx_timer_cb, (unsigned long)adapter);
  2457. setup_timer(&s->tx_timer, sge_tx_timer_cb, (unsigned long)adapter);
  2458. /*
  2459. * Initialize Forwarded Interrupt Queue lock.
  2460. */
  2461. spin_lock_init(&s->intrq_lock);
  2462. return 0;
  2463. }