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-rw-r--r--drivers/net/chelsio/sge.c1684
1 files changed, 1684 insertions, 0 deletions
diff --git a/drivers/net/chelsio/sge.c b/drivers/net/chelsio/sge.c
new file mode 100644
index 000000000000..53b41d99b00b
--- /dev/null
+++ b/drivers/net/chelsio/sge.c
@@ -0,0 +1,1684 @@
1/*****************************************************************************
2 * *
3 * File: sge.c *
4 * $Revision: 1.26 $ *
5 * $Date: 2005/06/21 18:29:48 $ *
6 * Description: *
7 * DMA engine. *
8 * part of the Chelsio 10Gb Ethernet Driver. *
9 * *
10 * This program is free software; you can redistribute it and/or modify *
11 * it under the terms of the GNU General Public License, version 2, as *
12 * published by the Free Software Foundation. *
13 * *
14 * You should have received a copy of the GNU General Public License along *
15 * with this program; if not, write to the Free Software Foundation, Inc., *
16 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
17 * *
18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED *
19 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF *
20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. *
21 * *
22 * http://www.chelsio.com *
23 * *
24 * Copyright (c) 2003 - 2005 Chelsio Communications, Inc. *
25 * All rights reserved. *
26 * *
27 * Maintainers: maintainers@chelsio.com *
28 * *
29 * Authors: Dimitrios Michailidis <dm@chelsio.com> *
30 * Tina Yang <tainay@chelsio.com> *
31 * Felix Marti <felix@chelsio.com> *
32 * Scott Bardone <sbardone@chelsio.com> *
33 * Kurt Ottaway <kottaway@chelsio.com> *
34 * Frank DiMambro <frank@chelsio.com> *
35 * *
36 * History: *
37 * *
38 ****************************************************************************/
39
40#include "common.h"
41
42#include <linux/config.h>
43#include <linux/types.h>
44#include <linux/errno.h>
45#include <linux/pci.h>
46#include <linux/netdevice.h>
47#include <linux/etherdevice.h>
48#include <linux/if_vlan.h>
49#include <linux/skbuff.h>
50#include <linux/init.h>
51#include <linux/mm.h>
52#include <linux/ip.h>
53#include <linux/in.h>
54#include <linux/if_arp.h>
55
56#include "cpl5_cmd.h"
57#include "sge.h"
58#include "regs.h"
59#include "espi.h"
60
61
62#ifdef NETIF_F_TSO
63#include <linux/tcp.h>
64#endif
65
66#define SGE_CMDQ_N 2
67#define SGE_FREELQ_N 2
68#define SGE_CMDQ0_E_N 1024
69#define SGE_CMDQ1_E_N 128
70#define SGE_FREEL_SIZE 4096
71#define SGE_JUMBO_FREEL_SIZE 512
72#define SGE_FREEL_REFILL_THRESH 16
73#define SGE_RESPQ_E_N 1024
74#define SGE_INTRTIMER_NRES 1000
75#define SGE_RX_COPY_THRES 256
76#define SGE_RX_SM_BUF_SIZE 1536
77
78# define SGE_RX_DROP_THRES 2
79
80#define SGE_RESPQ_REPLENISH_THRES (SGE_RESPQ_E_N / 4)
81
82/*
83 * Period of the TX buffer reclaim timer. This timer does not need to run
84 * frequently as TX buffers are usually reclaimed by new TX packets.
85 */
86#define TX_RECLAIM_PERIOD (HZ / 4)
87
88#ifndef NET_IP_ALIGN
89# define NET_IP_ALIGN 2
90#endif
91
92#define M_CMD_LEN 0x7fffffff
93#define V_CMD_LEN(v) (v)
94#define G_CMD_LEN(v) ((v) & M_CMD_LEN)
95#define V_CMD_GEN1(v) ((v) << 31)
96#define V_CMD_GEN2(v) (v)
97#define F_CMD_DATAVALID (1 << 1)
98#define F_CMD_SOP (1 << 2)
99#define V_CMD_EOP(v) ((v) << 3)
100
101/*
102 * Command queue, receive buffer list, and response queue descriptors.
103 */
104#if defined(__BIG_ENDIAN_BITFIELD)
105struct cmdQ_e {
106 u32 addr_lo;
107 u32 len_gen;
108 u32 flags;
109 u32 addr_hi;
110};
111
112struct freelQ_e {
113 u32 addr_lo;
114 u32 len_gen;
115 u32 gen2;
116 u32 addr_hi;
117};
118
119struct respQ_e {
120 u32 Qsleeping : 4;
121 u32 Cmdq1CreditReturn : 5;
122 u32 Cmdq1DmaComplete : 5;
123 u32 Cmdq0CreditReturn : 5;
124 u32 Cmdq0DmaComplete : 5;
125 u32 FreelistQid : 2;
126 u32 CreditValid : 1;
127 u32 DataValid : 1;
128 u32 Offload : 1;
129 u32 Eop : 1;
130 u32 Sop : 1;
131 u32 GenerationBit : 1;
132 u32 BufferLength;
133};
134#elif defined(__LITTLE_ENDIAN_BITFIELD)
135struct cmdQ_e {
136 u32 len_gen;
137 u32 addr_lo;
138 u32 addr_hi;
139 u32 flags;
140};
141
142struct freelQ_e {
143 u32 len_gen;
144 u32 addr_lo;
145 u32 addr_hi;
146 u32 gen2;
147};
148
149struct respQ_e {
150 u32 BufferLength;
151 u32 GenerationBit : 1;
152 u32 Sop : 1;
153 u32 Eop : 1;
154 u32 Offload : 1;
155 u32 DataValid : 1;
156 u32 CreditValid : 1;
157 u32 FreelistQid : 2;
158 u32 Cmdq0DmaComplete : 5;
159 u32 Cmdq0CreditReturn : 5;
160 u32 Cmdq1DmaComplete : 5;
161 u32 Cmdq1CreditReturn : 5;
162 u32 Qsleeping : 4;
163} ;
164#endif
165
166/*
167 * SW Context Command and Freelist Queue Descriptors
168 */
169struct cmdQ_ce {
170 struct sk_buff *skb;
171 DECLARE_PCI_UNMAP_ADDR(dma_addr);
172 DECLARE_PCI_UNMAP_LEN(dma_len);
173};
174
175struct freelQ_ce {
176 struct sk_buff *skb;
177 DECLARE_PCI_UNMAP_ADDR(dma_addr);
178 DECLARE_PCI_UNMAP_LEN(dma_len);
179};
180
181/*
182 * SW command, freelist and response rings
183 */
184struct cmdQ {
185 unsigned long status; /* HW DMA fetch status */
186 unsigned int in_use; /* # of in-use command descriptors */
187 unsigned int size; /* # of descriptors */
188 unsigned int processed; /* total # of descs HW has processed */
189 unsigned int cleaned; /* total # of descs SW has reclaimed */
190 unsigned int stop_thres; /* SW TX queue suspend threshold */
191 u16 pidx; /* producer index (SW) */
192 u16 cidx; /* consumer index (HW) */
193 u8 genbit; /* current generation (=valid) bit */
194 u8 sop; /* is next entry start of packet? */
195 struct cmdQ_e *entries; /* HW command descriptor Q */
196 struct cmdQ_ce *centries; /* SW command context descriptor Q */
197 spinlock_t lock; /* Lock to protect cmdQ enqueuing */
198 dma_addr_t dma_addr; /* DMA addr HW command descriptor Q */
199};
200
201struct freelQ {
202 unsigned int credits; /* # of available RX buffers */
203 unsigned int size; /* free list capacity */
204 u16 pidx; /* producer index (SW) */
205 u16 cidx; /* consumer index (HW) */
206 u16 rx_buffer_size; /* Buffer size on this free list */
207 u16 dma_offset; /* DMA offset to align IP headers */
208 u16 recycleq_idx; /* skb recycle q to use */
209 u8 genbit; /* current generation (=valid) bit */
210 struct freelQ_e *entries; /* HW freelist descriptor Q */
211 struct freelQ_ce *centries; /* SW freelist context descriptor Q */
212 dma_addr_t dma_addr; /* DMA addr HW freelist descriptor Q */
213};
214
215struct respQ {
216 unsigned int credits; /* credits to be returned to SGE */
217 unsigned int size; /* # of response Q descriptors */
218 u16 cidx; /* consumer index (SW) */
219 u8 genbit; /* current generation(=valid) bit */
220 struct respQ_e *entries; /* HW response descriptor Q */
221 dma_addr_t dma_addr; /* DMA addr HW response descriptor Q */
222};
223
224/* Bit flags for cmdQ.status */
225enum {
226 CMDQ_STAT_RUNNING = 1, /* fetch engine is running */
227 CMDQ_STAT_LAST_PKT_DB = 2 /* last packet rung the doorbell */
228};
229
230/*
231 * Main SGE data structure
232 *
233 * Interrupts are handled by a single CPU and it is likely that on a MP system
234 * the application is migrated to another CPU. In that scenario, we try to
235 * seperate the RX(in irq context) and TX state in order to decrease memory
236 * contention.
237 */
238struct sge {
239 struct adapter *adapter; /* adapter backpointer */
240 struct net_device *netdev; /* netdevice backpointer */
241 struct freelQ freelQ[SGE_FREELQ_N]; /* buffer free lists */
242 struct respQ respQ; /* response Q */
243 unsigned long stopped_tx_queues; /* bitmap of suspended Tx queues */
244 unsigned int rx_pkt_pad; /* RX padding for L2 packets */
245 unsigned int jumbo_fl; /* jumbo freelist Q index */
246 unsigned int intrtimer_nres; /* no-resource interrupt timer */
247 unsigned int fixed_intrtimer;/* non-adaptive interrupt timer */
248 struct timer_list tx_reclaim_timer; /* reclaims TX buffers */
249 struct timer_list espibug_timer;
250 unsigned int espibug_timeout;
251 struct sk_buff *espibug_skb;
252 u32 sge_control; /* shadow value of sge control reg */
253 struct sge_intr_counts stats;
254 struct sge_port_stats port_stats[MAX_NPORTS];
255 struct cmdQ cmdQ[SGE_CMDQ_N] ____cacheline_aligned_in_smp;
256};
257
258/*
259 * PIO to indicate that memory mapped Q contains valid descriptor(s).
260 */
261static inline void doorbell_pio(struct adapter *adapter, u32 val)
262{
263 wmb();
264 writel(val, adapter->regs + A_SG_DOORBELL);
265}
266
267/*
268 * Frees all RX buffers on the freelist Q. The caller must make sure that
269 * the SGE is turned off before calling this function.
270 */
271static void free_freelQ_buffers(struct pci_dev *pdev, struct freelQ *q)
272{
273 unsigned int cidx = q->cidx;
274
275 while (q->credits--) {
276 struct freelQ_ce *ce = &q->centries[cidx];
277
278 pci_unmap_single(pdev, pci_unmap_addr(ce, dma_addr),
279 pci_unmap_len(ce, dma_len),
280 PCI_DMA_FROMDEVICE);
281 dev_kfree_skb(ce->skb);
282 ce->skb = NULL;
283 if (++cidx == q->size)
284 cidx = 0;
285 }
286}
287
288/*
289 * Free RX free list and response queue resources.
290 */
291static void free_rx_resources(struct sge *sge)
292{
293 struct pci_dev *pdev = sge->adapter->pdev;
294 unsigned int size, i;
295
296 if (sge->respQ.entries) {
297 size = sizeof(struct respQ_e) * sge->respQ.size;
298 pci_free_consistent(pdev, size, sge->respQ.entries,
299 sge->respQ.dma_addr);
300 }
301
302 for (i = 0; i < SGE_FREELQ_N; i++) {
303 struct freelQ *q = &sge->freelQ[i];
304
305 if (q->centries) {
306 free_freelQ_buffers(pdev, q);
307 kfree(q->centries);
308 }
309 if (q->entries) {
310 size = sizeof(struct freelQ_e) * q->size;
311 pci_free_consistent(pdev, size, q->entries,
312 q->dma_addr);
313 }
314 }
315}
316
317/*
318 * Allocates basic RX resources, consisting of memory mapped freelist Qs and a
319 * response queue.
320 */
321static int alloc_rx_resources(struct sge *sge, struct sge_params *p)
322{
323 struct pci_dev *pdev = sge->adapter->pdev;
324 unsigned int size, i;
325
326 for (i = 0; i < SGE_FREELQ_N; i++) {
327 struct freelQ *q = &sge->freelQ[i];
328
329 q->genbit = 1;
330 q->size = p->freelQ_size[i];
331 q->dma_offset = sge->rx_pkt_pad ? 0 : NET_IP_ALIGN;
332 size = sizeof(struct freelQ_e) * q->size;
333 q->entries = (struct freelQ_e *)
334 pci_alloc_consistent(pdev, size, &q->dma_addr);
335 if (!q->entries)
336 goto err_no_mem;
337 memset(q->entries, 0, size);
338 size = sizeof(struct freelQ_ce) * q->size;
339 q->centries = kmalloc(size, GFP_KERNEL);
340 if (!q->centries)
341 goto err_no_mem;
342 memset(q->centries, 0, size);
343 }
344
345 /*
346 * Calculate the buffer sizes for the two free lists. FL0 accommodates
347 * regular sized Ethernet frames, FL1 is sized not to exceed 16K,
348 * including all the sk_buff overhead.
349 *
350 * Note: For T2 FL0 and FL1 are reversed.
351 */
352 sge->freelQ[!sge->jumbo_fl].rx_buffer_size = SGE_RX_SM_BUF_SIZE +
353 sizeof(struct cpl_rx_data) +
354 sge->freelQ[!sge->jumbo_fl].dma_offset;
355 sge->freelQ[sge->jumbo_fl].rx_buffer_size = (16 * 1024) -
356 SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
357
358 /*
359 * Setup which skb recycle Q should be used when recycling buffers from
360 * each free list.
361 */
362 sge->freelQ[!sge->jumbo_fl].recycleq_idx = 0;
363 sge->freelQ[sge->jumbo_fl].recycleq_idx = 1;
364
365 sge->respQ.genbit = 1;
366 sge->respQ.size = SGE_RESPQ_E_N;
367 sge->respQ.credits = 0;
368 size = sizeof(struct respQ_e) * sge->respQ.size;
369 sge->respQ.entries = (struct respQ_e *)
370 pci_alloc_consistent(pdev, size, &sge->respQ.dma_addr);
371 if (!sge->respQ.entries)
372 goto err_no_mem;
373 memset(sge->respQ.entries, 0, size);
374 return 0;
375
376err_no_mem:
377 free_rx_resources(sge);
378 return -ENOMEM;
379}
380
381/*
382 * Reclaims n TX descriptors and frees the buffers associated with them.
383 */
384static void free_cmdQ_buffers(struct sge *sge, struct cmdQ *q, unsigned int n)
385{
386 struct cmdQ_ce *ce;
387 struct pci_dev *pdev = sge->adapter->pdev;
388 unsigned int cidx = q->cidx;
389
390 q->in_use -= n;
391 ce = &q->centries[cidx];
392 while (n--) {
393 if (q->sop)
394 pci_unmap_single(pdev, pci_unmap_addr(ce, dma_addr),
395 pci_unmap_len(ce, dma_len),
396 PCI_DMA_TODEVICE);
397 else
398 pci_unmap_page(pdev, pci_unmap_addr(ce, dma_addr),
399 pci_unmap_len(ce, dma_len),
400 PCI_DMA_TODEVICE);
401 q->sop = 0;
402 if (ce->skb) {
403 dev_kfree_skb(ce->skb);
404 q->sop = 1;
405 }
406 ce++;
407 if (++cidx == q->size) {
408 cidx = 0;
409 ce = q->centries;
410 }
411 }
412 q->cidx = cidx;
413}
414
415/*
416 * Free TX resources.
417 *
418 * Assumes that SGE is stopped and all interrupts are disabled.
419 */
420static void free_tx_resources(struct sge *sge)
421{
422 struct pci_dev *pdev = sge->adapter->pdev;
423 unsigned int size, i;
424
425 for (i = 0; i < SGE_CMDQ_N; i++) {
426 struct cmdQ *q = &sge->cmdQ[i];
427
428 if (q->centries) {
429 if (q->in_use)
430 free_cmdQ_buffers(sge, q, q->in_use);
431 kfree(q->centries);
432 }
433 if (q->entries) {
434 size = sizeof(struct cmdQ_e) * q->size;
435 pci_free_consistent(pdev, size, q->entries,
436 q->dma_addr);
437 }
438 }
439}
440
441/*
442 * Allocates basic TX resources, consisting of memory mapped command Qs.
443 */
444static int alloc_tx_resources(struct sge *sge, struct sge_params *p)
445{
446 struct pci_dev *pdev = sge->adapter->pdev;
447 unsigned int size, i;
448
449 for (i = 0; i < SGE_CMDQ_N; i++) {
450 struct cmdQ *q = &sge->cmdQ[i];
451
452 q->genbit = 1;
453 q->sop = 1;
454 q->size = p->cmdQ_size[i];
455 q->in_use = 0;
456 q->status = 0;
457 q->processed = q->cleaned = 0;
458 q->stop_thres = 0;
459 spin_lock_init(&q->lock);
460 size = sizeof(struct cmdQ_e) * q->size;
461 q->entries = (struct cmdQ_e *)
462 pci_alloc_consistent(pdev, size, &q->dma_addr);
463 if (!q->entries)
464 goto err_no_mem;
465 memset(q->entries, 0, size);
466 size = sizeof(struct cmdQ_ce) * q->size;
467 q->centries = kmalloc(size, GFP_KERNEL);
468 if (!q->centries)
469 goto err_no_mem;
470 memset(q->centries, 0, size);
471 }
472
473 /*
474 * CommandQ 0 handles Ethernet and TOE packets, while queue 1 is TOE
475 * only. For queue 0 set the stop threshold so we can handle one more
476 * packet from each port, plus reserve an additional 24 entries for
477 * Ethernet packets only. Queue 1 never suspends nor do we reserve
478 * space for Ethernet packets.
479 */
480 sge->cmdQ[0].stop_thres = sge->adapter->params.nports *
481 (MAX_SKB_FRAGS + 1);
482 return 0;
483
484err_no_mem:
485 free_tx_resources(sge);
486 return -ENOMEM;
487}
488
489static inline void setup_ring_params(struct adapter *adapter, u64 addr,
490 u32 size, int base_reg_lo,
491 int base_reg_hi, int size_reg)
492{
493 writel((u32)addr, adapter->regs + base_reg_lo);
494 writel(addr >> 32, adapter->regs + base_reg_hi);
495 writel(size, adapter->regs + size_reg);
496}
497
498/*
499 * Enable/disable VLAN acceleration.
500 */
501void t1_set_vlan_accel(struct adapter *adapter, int on_off)
502{
503 struct sge *sge = adapter->sge;
504
505 sge->sge_control &= ~F_VLAN_XTRACT;
506 if (on_off)
507 sge->sge_control |= F_VLAN_XTRACT;
508 if (adapter->open_device_map) {
509 writel(sge->sge_control, adapter->regs + A_SG_CONTROL);
510 readl(adapter->regs + A_SG_CONTROL); /* flush */
511 }
512}
513
514/*
515 * Programs the various SGE registers. However, the engine is not yet enabled,
516 * but sge->sge_control is setup and ready to go.
517 */
518static void configure_sge(struct sge *sge, struct sge_params *p)
519{
520 struct adapter *ap = sge->adapter;
521
522 writel(0, ap->regs + A_SG_CONTROL);
523 setup_ring_params(ap, sge->cmdQ[0].dma_addr, sge->cmdQ[0].size,
524 A_SG_CMD0BASELWR, A_SG_CMD0BASEUPR, A_SG_CMD0SIZE);
525 setup_ring_params(ap, sge->cmdQ[1].dma_addr, sge->cmdQ[1].size,
526 A_SG_CMD1BASELWR, A_SG_CMD1BASEUPR, A_SG_CMD1SIZE);
527 setup_ring_params(ap, sge->freelQ[0].dma_addr,
528 sge->freelQ[0].size, A_SG_FL0BASELWR,
529 A_SG_FL0BASEUPR, A_SG_FL0SIZE);
530 setup_ring_params(ap, sge->freelQ[1].dma_addr,
531 sge->freelQ[1].size, A_SG_FL1BASELWR,
532 A_SG_FL1BASEUPR, A_SG_FL1SIZE);
533
534 /* The threshold comparison uses <. */
535 writel(SGE_RX_SM_BUF_SIZE + 1, ap->regs + A_SG_FLTHRESHOLD);
536
537 setup_ring_params(ap, sge->respQ.dma_addr, sge->respQ.size,
538 A_SG_RSPBASELWR, A_SG_RSPBASEUPR, A_SG_RSPSIZE);
539 writel((u32)sge->respQ.size - 1, ap->regs + A_SG_RSPQUEUECREDIT);
540
541 sge->sge_control = F_CMDQ0_ENABLE | F_CMDQ1_ENABLE | F_FL0_ENABLE |
542 F_FL1_ENABLE | F_CPL_ENABLE | F_RESPONSE_QUEUE_ENABLE |
543 V_CMDQ_PRIORITY(2) | F_DISABLE_CMDQ1_GTS | F_ISCSI_COALESCE |
544 F_DISABLE_FL0_GTS | F_DISABLE_FL1_GTS |
545 V_RX_PKT_OFFSET(sge->rx_pkt_pad);
546
547#if defined(__BIG_ENDIAN_BITFIELD)
548 sge->sge_control |= F_ENABLE_BIG_ENDIAN;
549#endif
550
551 /* Initialize no-resource timer */
552 sge->intrtimer_nres = SGE_INTRTIMER_NRES * core_ticks_per_usec(ap);
553
554 t1_sge_set_coalesce_params(sge, p);
555}
556
557/*
558 * Return the payload capacity of the jumbo free-list buffers.
559 */
560static inline unsigned int jumbo_payload_capacity(const struct sge *sge)
561{
562 return sge->freelQ[sge->jumbo_fl].rx_buffer_size -
563 sge->freelQ[sge->jumbo_fl].dma_offset -
564 sizeof(struct cpl_rx_data);
565}
566
567/*
568 * Frees all SGE related resources and the sge structure itself
569 */
570void t1_sge_destroy(struct sge *sge)
571{
572 if (sge->espibug_skb)
573 kfree_skb(sge->espibug_skb);
574
575 free_tx_resources(sge);
576 free_rx_resources(sge);
577 kfree(sge);
578}
579
580/*
581 * Allocates new RX buffers on the freelist Q (and tracks them on the freelist
582 * context Q) until the Q is full or alloc_skb fails.
583 *
584 * It is possible that the generation bits already match, indicating that the
585 * buffer is already valid and nothing needs to be done. This happens when we
586 * copied a received buffer into a new sk_buff during the interrupt processing.
587 *
588 * If the SGE doesn't automatically align packets properly (!sge->rx_pkt_pad),
589 * we specify a RX_OFFSET in order to make sure that the IP header is 4B
590 * aligned.
591 */
592static void refill_free_list(struct sge *sge, struct freelQ *q)
593{
594 struct pci_dev *pdev = sge->adapter->pdev;
595 struct freelQ_ce *ce = &q->centries[q->pidx];
596 struct freelQ_e *e = &q->entries[q->pidx];
597 unsigned int dma_len = q->rx_buffer_size - q->dma_offset;
598
599
600 while (q->credits < q->size) {
601 struct sk_buff *skb;
602 dma_addr_t mapping;
603
604 skb = alloc_skb(q->rx_buffer_size, GFP_ATOMIC);
605 if (!skb)
606 break;
607
608 skb_reserve(skb, q->dma_offset);
609 mapping = pci_map_single(pdev, skb->data, dma_len,
610 PCI_DMA_FROMDEVICE);
611 ce->skb = skb;
612 pci_unmap_addr_set(ce, dma_addr, mapping);
613 pci_unmap_len_set(ce, dma_len, dma_len);
614 e->addr_lo = (u32)mapping;
615 e->addr_hi = (u64)mapping >> 32;
616 e->len_gen = V_CMD_LEN(dma_len) | V_CMD_GEN1(q->genbit);
617 wmb();
618 e->gen2 = V_CMD_GEN2(q->genbit);
619
620 e++;
621 ce++;
622 if (++q->pidx == q->size) {
623 q->pidx = 0;
624 q->genbit ^= 1;
625 ce = q->centries;
626 e = q->entries;
627 }
628 q->credits++;
629 }
630
631}
632
633/*
634 * Calls refill_free_list for both free lists. If we cannot fill at least 1/4
635 * of both rings, we go into 'few interrupt mode' in order to give the system
636 * time to free up resources.
637 */
638static void freelQs_empty(struct sge *sge)
639{
640 struct adapter *adapter = sge->adapter;
641 u32 irq_reg = readl(adapter->regs + A_SG_INT_ENABLE);
642 u32 irqholdoff_reg;
643
644 refill_free_list(sge, &sge->freelQ[0]);
645 refill_free_list(sge, &sge->freelQ[1]);
646
647 if (sge->freelQ[0].credits > (sge->freelQ[0].size >> 2) &&
648 sge->freelQ[1].credits > (sge->freelQ[1].size >> 2)) {
649 irq_reg |= F_FL_EXHAUSTED;
650 irqholdoff_reg = sge->fixed_intrtimer;
651 } else {
652 /* Clear the F_FL_EXHAUSTED interrupts for now */
653 irq_reg &= ~F_FL_EXHAUSTED;
654 irqholdoff_reg = sge->intrtimer_nres;
655 }
656 writel(irqholdoff_reg, adapter->regs + A_SG_INTRTIMER);
657 writel(irq_reg, adapter->regs + A_SG_INT_ENABLE);
658
659 /* We reenable the Qs to force a freelist GTS interrupt later */
660 doorbell_pio(adapter, F_FL0_ENABLE | F_FL1_ENABLE);
661}
662
663#define SGE_PL_INTR_MASK (F_PL_INTR_SGE_ERR | F_PL_INTR_SGE_DATA)
664#define SGE_INT_FATAL (F_RESPQ_OVERFLOW | F_PACKET_TOO_BIG | F_PACKET_MISMATCH)
665#define SGE_INT_ENABLE (F_RESPQ_EXHAUSTED | F_RESPQ_OVERFLOW | \
666 F_FL_EXHAUSTED | F_PACKET_TOO_BIG | F_PACKET_MISMATCH)
667
668/*
669 * Disable SGE Interrupts
670 */
671void t1_sge_intr_disable(struct sge *sge)
672{
673 u32 val = readl(sge->adapter->regs + A_PL_ENABLE);
674
675 writel(val & ~SGE_PL_INTR_MASK, sge->adapter->regs + A_PL_ENABLE);
676 writel(0, sge->adapter->regs + A_SG_INT_ENABLE);
677}
678
679/*
680 * Enable SGE interrupts.
681 */
682void t1_sge_intr_enable(struct sge *sge)
683{
684 u32 en = SGE_INT_ENABLE;
685 u32 val = readl(sge->adapter->regs + A_PL_ENABLE);
686
687 if (sge->adapter->flags & TSO_CAPABLE)
688 en &= ~F_PACKET_TOO_BIG;
689 writel(en, sge->adapter->regs + A_SG_INT_ENABLE);
690 writel(val | SGE_PL_INTR_MASK, sge->adapter->regs + A_PL_ENABLE);
691}
692
693/*
694 * Clear SGE interrupts.
695 */
696void t1_sge_intr_clear(struct sge *sge)
697{
698 writel(SGE_PL_INTR_MASK, sge->adapter->regs + A_PL_CAUSE);
699 writel(0xffffffff, sge->adapter->regs + A_SG_INT_CAUSE);
700}
701
702/*
703 * SGE 'Error' interrupt handler
704 */
705int t1_sge_intr_error_handler(struct sge *sge)
706{
707 struct adapter *adapter = sge->adapter;
708 u32 cause = readl(adapter->regs + A_SG_INT_CAUSE);
709
710 if (adapter->flags & TSO_CAPABLE)
711 cause &= ~F_PACKET_TOO_BIG;
712 if (cause & F_RESPQ_EXHAUSTED)
713 sge->stats.respQ_empty++;
714 if (cause & F_RESPQ_OVERFLOW) {
715 sge->stats.respQ_overflow++;
716 CH_ALERT("%s: SGE response queue overflow\n",
717 adapter->name);
718 }
719 if (cause & F_FL_EXHAUSTED) {
720 sge->stats.freelistQ_empty++;
721 freelQs_empty(sge);
722 }
723 if (cause & F_PACKET_TOO_BIG) {
724 sge->stats.pkt_too_big++;
725 CH_ALERT("%s: SGE max packet size exceeded\n",
726 adapter->name);
727 }
728 if (cause & F_PACKET_MISMATCH) {
729 sge->stats.pkt_mismatch++;
730 CH_ALERT("%s: SGE packet mismatch\n", adapter->name);
731 }
732 if (cause & SGE_INT_FATAL)
733 t1_fatal_err(adapter);
734
735 writel(cause, adapter->regs + A_SG_INT_CAUSE);
736 return 0;
737}
738
739const struct sge_intr_counts *t1_sge_get_intr_counts(struct sge *sge)
740{
741 return &sge->stats;
742}
743
744const struct sge_port_stats *t1_sge_get_port_stats(struct sge *sge, int port)
745{
746 return &sge->port_stats[port];
747}
748
749/**
750 * recycle_fl_buf - recycle a free list buffer
751 * @fl: the free list
752 * @idx: index of buffer to recycle
753 *
754 * Recycles the specified buffer on the given free list by adding it at
755 * the next available slot on the list.
756 */
757static void recycle_fl_buf(struct freelQ *fl, int idx)
758{
759 struct freelQ_e *from = &fl->entries[idx];
760 struct freelQ_e *to = &fl->entries[fl->pidx];
761
762 fl->centries[fl->pidx] = fl->centries[idx];
763 to->addr_lo = from->addr_lo;
764 to->addr_hi = from->addr_hi;
765 to->len_gen = G_CMD_LEN(from->len_gen) | V_CMD_GEN1(fl->genbit);
766 wmb();
767 to->gen2 = V_CMD_GEN2(fl->genbit);
768 fl->credits++;
769
770 if (++fl->pidx == fl->size) {
771 fl->pidx = 0;
772 fl->genbit ^= 1;
773 }
774}
775
776/**
777 * get_packet - return the next ingress packet buffer
778 * @pdev: the PCI device that received the packet
779 * @fl: the SGE free list holding the packet
780 * @len: the actual packet length, excluding any SGE padding
781 * @dma_pad: padding at beginning of buffer left by SGE DMA
782 * @skb_pad: padding to be used if the packet is copied
783 * @copy_thres: length threshold under which a packet should be copied
784 * @drop_thres: # of remaining buffers before we start dropping packets
785 *
786 * Get the next packet from a free list and complete setup of the
787 * sk_buff. If the packet is small we make a copy and recycle the
788 * original buffer, otherwise we use the original buffer itself. If a
789 * positive drop threshold is supplied packets are dropped and their
790 * buffers recycled if (a) the number of remaining buffers is under the
791 * threshold and the packet is too big to copy, or (b) the packet should
792 * be copied but there is no memory for the copy.
793 */
794static inline struct sk_buff *get_packet(struct pci_dev *pdev,
795 struct freelQ *fl, unsigned int len,
796 int dma_pad, int skb_pad,
797 unsigned int copy_thres,
798 unsigned int drop_thres)
799{
800 struct sk_buff *skb;
801 struct freelQ_ce *ce = &fl->centries[fl->cidx];
802
803 if (len < copy_thres) {
804 skb = alloc_skb(len + skb_pad, GFP_ATOMIC);
805 if (likely(skb != NULL)) {
806 skb_reserve(skb, skb_pad);
807 skb_put(skb, len);
808 pci_dma_sync_single_for_cpu(pdev,
809 pci_unmap_addr(ce, dma_addr),
810 pci_unmap_len(ce, dma_len),
811 PCI_DMA_FROMDEVICE);
812 memcpy(skb->data, ce->skb->data + dma_pad, len);
813 pci_dma_sync_single_for_device(pdev,
814 pci_unmap_addr(ce, dma_addr),
815 pci_unmap_len(ce, dma_len),
816 PCI_DMA_FROMDEVICE);
817 } else if (!drop_thres)
818 goto use_orig_buf;
819
820 recycle_fl_buf(fl, fl->cidx);
821 return skb;
822 }
823
824 if (fl->credits < drop_thres) {
825 recycle_fl_buf(fl, fl->cidx);
826 return NULL;
827 }
828
829use_orig_buf:
830 pci_unmap_single(pdev, pci_unmap_addr(ce, dma_addr),
831 pci_unmap_len(ce, dma_len), PCI_DMA_FROMDEVICE);
832 skb = ce->skb;
833 skb_reserve(skb, dma_pad);
834 skb_put(skb, len);
835 return skb;
836}
837
838/**
839 * unexpected_offload - handle an unexpected offload packet
840 * @adapter: the adapter
841 * @fl: the free list that received the packet
842 *
843 * Called when we receive an unexpected offload packet (e.g., the TOE
844 * function is disabled or the card is a NIC). Prints a message and
845 * recycles the buffer.
846 */
847static void unexpected_offload(struct adapter *adapter, struct freelQ *fl)
848{
849 struct freelQ_ce *ce = &fl->centries[fl->cidx];
850 struct sk_buff *skb = ce->skb;
851
852 pci_dma_sync_single_for_cpu(adapter->pdev, pci_unmap_addr(ce, dma_addr),
853 pci_unmap_len(ce, dma_len), PCI_DMA_FROMDEVICE);
854 CH_ERR("%s: unexpected offload packet, cmd %u\n",
855 adapter->name, *skb->data);
856 recycle_fl_buf(fl, fl->cidx);
857}
858
859/*
860 * Write the command descriptors to transmit the given skb starting at
861 * descriptor pidx with the given generation.
862 */
863static inline void write_tx_descs(struct adapter *adapter, struct sk_buff *skb,
864 unsigned int pidx, unsigned int gen,
865 struct cmdQ *q)
866{
867 dma_addr_t mapping;
868 struct cmdQ_e *e, *e1;
869 struct cmdQ_ce *ce;
870 unsigned int i, flags, nfrags = skb_shinfo(skb)->nr_frags;
871
872 mapping = pci_map_single(adapter->pdev, skb->data,
873 skb->len - skb->data_len, PCI_DMA_TODEVICE);
874 ce = &q->centries[pidx];
875 ce->skb = NULL;
876 pci_unmap_addr_set(ce, dma_addr, mapping);
877 pci_unmap_len_set(ce, dma_len, skb->len - skb->data_len);
878
879 flags = F_CMD_DATAVALID | F_CMD_SOP | V_CMD_EOP(nfrags == 0) |
880 V_CMD_GEN2(gen);
881 e = &q->entries[pidx];
882 e->addr_lo = (u32)mapping;
883 e->addr_hi = (u64)mapping >> 32;
884 e->len_gen = V_CMD_LEN(skb->len - skb->data_len) | V_CMD_GEN1(gen);
885 for (e1 = e, i = 0; nfrags--; i++) {
886 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
887
888 ce++;
889 e1++;
890 if (++pidx == q->size) {
891 pidx = 0;
892 gen ^= 1;
893 ce = q->centries;
894 e1 = q->entries;
895 }
896
897 mapping = pci_map_page(adapter->pdev, frag->page,
898 frag->page_offset, frag->size,
899 PCI_DMA_TODEVICE);
900 ce->skb = NULL;
901 pci_unmap_addr_set(ce, dma_addr, mapping);
902 pci_unmap_len_set(ce, dma_len, frag->size);
903
904 e1->addr_lo = (u32)mapping;
905 e1->addr_hi = (u64)mapping >> 32;
906 e1->len_gen = V_CMD_LEN(frag->size) | V_CMD_GEN1(gen);
907 e1->flags = F_CMD_DATAVALID | V_CMD_EOP(nfrags == 0) |
908 V_CMD_GEN2(gen);
909 }
910
911 ce->skb = skb;
912 wmb();
913 e->flags = flags;
914}
915
916/*
917 * Clean up completed Tx buffers.
918 */
919static inline void reclaim_completed_tx(struct sge *sge, struct cmdQ *q)
920{
921 unsigned int reclaim = q->processed - q->cleaned;
922
923 if (reclaim) {
924 free_cmdQ_buffers(sge, q, reclaim);
925 q->cleaned += reclaim;
926 }
927}
928
929#ifndef SET_ETHTOOL_OPS
930# define __netif_rx_complete(dev) netif_rx_complete(dev)
931#endif
932
933/*
934 * We cannot use the standard netif_rx_schedule_prep() because we have multiple
935 * ports plus the TOE all multiplexing onto a single response queue, therefore
936 * accepting new responses cannot depend on the state of any particular port.
937 * So define our own equivalent that omits the netif_running() test.
938 */
939static inline int napi_schedule_prep(struct net_device *dev)
940{
941 return !test_and_set_bit(__LINK_STATE_RX_SCHED, &dev->state);
942}
943
944
945/**
946 * sge_rx - process an ingress ethernet packet
947 * @sge: the sge structure
948 * @fl: the free list that contains the packet buffer
949 * @len: the packet length
950 *
951 * Process an ingress ethernet pakcet and deliver it to the stack.
952 */
953static int sge_rx(struct sge *sge, struct freelQ *fl, unsigned int len)
954{
955 struct sk_buff *skb;
956 struct cpl_rx_pkt *p;
957 struct adapter *adapter = sge->adapter;
958
959 sge->stats.ethernet_pkts++;
960 skb = get_packet(adapter->pdev, fl, len - sge->rx_pkt_pad,
961 sge->rx_pkt_pad, 2, SGE_RX_COPY_THRES,
962 SGE_RX_DROP_THRES);
963 if (!skb) {
964 sge->port_stats[0].rx_drops++; /* charge only port 0 for now */
965 return 0;
966 }
967
968 p = (struct cpl_rx_pkt *)skb->data;
969 skb_pull(skb, sizeof(*p));
970 skb->dev = adapter->port[p->iff].dev;
971 skb->dev->last_rx = jiffies;
972 skb->protocol = eth_type_trans(skb, skb->dev);
973 if ((adapter->flags & RX_CSUM_ENABLED) && p->csum == 0xffff &&
974 skb->protocol == htons(ETH_P_IP) &&
975 (skb->data[9] == IPPROTO_TCP || skb->data[9] == IPPROTO_UDP)) {
976 sge->port_stats[p->iff].rx_cso_good++;
977 skb->ip_summed = CHECKSUM_UNNECESSARY;
978 } else
979 skb->ip_summed = CHECKSUM_NONE;
980
981 if (unlikely(adapter->vlan_grp && p->vlan_valid)) {
982 sge->port_stats[p->iff].vlan_xtract++;
983 if (adapter->params.sge.polling)
984 vlan_hwaccel_receive_skb(skb, adapter->vlan_grp,
985 ntohs(p->vlan));
986 else
987 vlan_hwaccel_rx(skb, adapter->vlan_grp,
988 ntohs(p->vlan));
989 } else if (adapter->params.sge.polling)
990 netif_receive_skb(skb);
991 else
992 netif_rx(skb);
993 return 0;
994}
995
996/*
997 * Returns true if a command queue has enough available descriptors that
998 * we can resume Tx operation after temporarily disabling its packet queue.
999 */
1000static inline int enough_free_Tx_descs(const struct cmdQ *q)
1001{
1002 unsigned int r = q->processed - q->cleaned;
1003
1004 return q->in_use - r < (q->size >> 1);
1005}
1006
1007/*
1008 * Called when sufficient space has become available in the SGE command queues
1009 * after the Tx packet schedulers have been suspended to restart the Tx path.
1010 */
1011static void restart_tx_queues(struct sge *sge)
1012{
1013 struct adapter *adap = sge->adapter;
1014
1015 if (enough_free_Tx_descs(&sge->cmdQ[0])) {
1016 int i;
1017
1018 for_each_port(adap, i) {
1019 struct net_device *nd = adap->port[i].dev;
1020
1021 if (test_and_clear_bit(nd->if_port,
1022 &sge->stopped_tx_queues) &&
1023 netif_running(nd)) {
1024 sge->stats.cmdQ_restarted[3]++;
1025 netif_wake_queue(nd);
1026 }
1027 }
1028 }
1029}
1030
1031/*
1032 * update_tx_info is called from the interrupt handler/NAPI to return cmdQ0
1033 * information.
1034 */
1035static unsigned int update_tx_info(struct adapter *adapter,
1036 unsigned int flags,
1037 unsigned int pr0)
1038{
1039 struct sge *sge = adapter->sge;
1040 struct cmdQ *cmdq = &sge->cmdQ[0];
1041
1042 cmdq->processed += pr0;
1043
1044 if (flags & F_CMDQ0_ENABLE) {
1045 clear_bit(CMDQ_STAT_RUNNING, &cmdq->status);
1046
1047 if (cmdq->cleaned + cmdq->in_use != cmdq->processed &&
1048 !test_and_set_bit(CMDQ_STAT_LAST_PKT_DB, &cmdq->status)) {
1049 set_bit(CMDQ_STAT_RUNNING, &cmdq->status);
1050 writel(F_CMDQ0_ENABLE, adapter->regs + A_SG_DOORBELL);
1051 }
1052 flags &= ~F_CMDQ0_ENABLE;
1053 }
1054
1055 if (unlikely(sge->stopped_tx_queues != 0))
1056 restart_tx_queues(sge);
1057
1058 return flags;
1059}
1060
1061/*
1062 * Process SGE responses, up to the supplied budget. Returns the number of
1063 * responses processed. A negative budget is effectively unlimited.
1064 */
1065static int process_responses(struct adapter *adapter, int budget)
1066{
1067 struct sge *sge = adapter->sge;
1068 struct respQ *q = &sge->respQ;
1069 struct respQ_e *e = &q->entries[q->cidx];
1070 int budget_left = budget;
1071 unsigned int flags = 0;
1072 unsigned int cmdq_processed[SGE_CMDQ_N] = {0, 0};
1073
1074
1075 while (likely(budget_left && e->GenerationBit == q->genbit)) {
1076 flags |= e->Qsleeping;
1077
1078 cmdq_processed[0] += e->Cmdq0CreditReturn;
1079 cmdq_processed[1] += e->Cmdq1CreditReturn;
1080
1081 /* We batch updates to the TX side to avoid cacheline
1082 * ping-pong of TX state information on MP where the sender
1083 * might run on a different CPU than this function...
1084 */
1085 if (unlikely(flags & F_CMDQ0_ENABLE || cmdq_processed[0] > 64)) {
1086 flags = update_tx_info(adapter, flags, cmdq_processed[0]);
1087 cmdq_processed[0] = 0;
1088 }
1089 if (unlikely(cmdq_processed[1] > 16)) {
1090 sge->cmdQ[1].processed += cmdq_processed[1];
1091 cmdq_processed[1] = 0;
1092 }
1093 if (likely(e->DataValid)) {
1094 struct freelQ *fl = &sge->freelQ[e->FreelistQid];
1095
1096 if (unlikely(!e->Sop || !e->Eop))
1097 BUG();
1098 if (unlikely(e->Offload))
1099 unexpected_offload(adapter, fl);
1100 else
1101 sge_rx(sge, fl, e->BufferLength);
1102
1103 /*
1104 * Note: this depends on each packet consuming a
1105 * single free-list buffer; cf. the BUG above.
1106 */
1107 if (++fl->cidx == fl->size)
1108 fl->cidx = 0;
1109 if (unlikely(--fl->credits <
1110 fl->size - SGE_FREEL_REFILL_THRESH))
1111 refill_free_list(sge, fl);
1112 } else
1113 sge->stats.pure_rsps++;
1114
1115 e++;
1116 if (unlikely(++q->cidx == q->size)) {
1117 q->cidx = 0;
1118 q->genbit ^= 1;
1119 e = q->entries;
1120 }
1121 prefetch(e);
1122
1123 if (++q->credits > SGE_RESPQ_REPLENISH_THRES) {
1124 writel(q->credits, adapter->regs + A_SG_RSPQUEUECREDIT);
1125 q->credits = 0;
1126 }
1127 --budget_left;
1128 }
1129
1130 flags = update_tx_info(adapter, flags, cmdq_processed[0]);
1131 sge->cmdQ[1].processed += cmdq_processed[1];
1132
1133 budget -= budget_left;
1134 return budget;
1135}
1136
1137/*
1138 * A simpler version of process_responses() that handles only pure (i.e.,
1139 * non data-carrying) responses. Such respones are too light-weight to justify
1140 * calling a softirq when using NAPI, so we handle them specially in hard
1141 * interrupt context. The function is called with a pointer to a response,
1142 * which the caller must ensure is a valid pure response. Returns 1 if it
1143 * encounters a valid data-carrying response, 0 otherwise.
1144 */
1145static int process_pure_responses(struct adapter *adapter, struct respQ_e *e)
1146{
1147 struct sge *sge = adapter->sge;
1148 struct respQ *q = &sge->respQ;
1149 unsigned int flags = 0;
1150 unsigned int cmdq_processed[SGE_CMDQ_N] = {0, 0};
1151
1152 do {
1153 flags |= e->Qsleeping;
1154
1155 cmdq_processed[0] += e->Cmdq0CreditReturn;
1156 cmdq_processed[1] += e->Cmdq1CreditReturn;
1157
1158 e++;
1159 if (unlikely(++q->cidx == q->size)) {
1160 q->cidx = 0;
1161 q->genbit ^= 1;
1162 e = q->entries;
1163 }
1164 prefetch(e);
1165
1166 if (++q->credits > SGE_RESPQ_REPLENISH_THRES) {
1167 writel(q->credits, adapter->regs + A_SG_RSPQUEUECREDIT);
1168 q->credits = 0;
1169 }
1170 sge->stats.pure_rsps++;
1171 } while (e->GenerationBit == q->genbit && !e->DataValid);
1172
1173 flags = update_tx_info(adapter, flags, cmdq_processed[0]);
1174 sge->cmdQ[1].processed += cmdq_processed[1];
1175
1176 return e->GenerationBit == q->genbit;
1177}
1178
1179/*
1180 * Handler for new data events when using NAPI. This does not need any locking
1181 * or protection from interrupts as data interrupts are off at this point and
1182 * other adapter interrupts do not interfere.
1183 */
1184static int t1_poll(struct net_device *dev, int *budget)
1185{
1186 struct adapter *adapter = dev->priv;
1187 int effective_budget = min(*budget, dev->quota);
1188
1189 int work_done = process_responses(adapter, effective_budget);
1190 *budget -= work_done;
1191 dev->quota -= work_done;
1192
1193 if (work_done >= effective_budget)
1194 return 1;
1195
1196 __netif_rx_complete(dev);
1197
1198 /*
1199 * Because we don't atomically flush the following write it is
1200 * possible that in very rare cases it can reach the device in a way
1201 * that races with a new response being written plus an error interrupt
1202 * causing the NAPI interrupt handler below to return unhandled status
1203 * to the OS. To protect against this would require flushing the write
1204 * and doing both the write and the flush with interrupts off. Way too
1205 * expensive and unjustifiable given the rarity of the race.
1206 */
1207 writel(adapter->sge->respQ.cidx, adapter->regs + A_SG_SLEEPING);
1208 return 0;
1209}
1210
1211/*
1212 * Returns true if the device is already scheduled for polling.
1213 */
1214static inline int napi_is_scheduled(struct net_device *dev)
1215{
1216 return test_bit(__LINK_STATE_RX_SCHED, &dev->state);
1217}
1218
1219/*
1220 * NAPI version of the main interrupt handler.
1221 */
1222static irqreturn_t t1_interrupt_napi(int irq, void *data, struct pt_regs *regs)
1223{
1224 int handled;
1225 struct adapter *adapter = data;
1226 struct sge *sge = adapter->sge;
1227 struct respQ *q = &adapter->sge->respQ;
1228
1229 /*
1230 * Clear the SGE_DATA interrupt first thing. Normally the NAPI
1231 * handler has control of the response queue and the interrupt handler
1232 * can look at the queue reliably only once it knows NAPI is off.
1233 * We can't wait that long to clear the SGE_DATA interrupt because we
1234 * could race with t1_poll rearming the SGE interrupt, so we need to
1235 * clear the interrupt speculatively and really early on.
1236 */
1237 writel(F_PL_INTR_SGE_DATA, adapter->regs + A_PL_CAUSE);
1238
1239 spin_lock(&adapter->async_lock);
1240 if (!napi_is_scheduled(sge->netdev)) {
1241 struct respQ_e *e = &q->entries[q->cidx];
1242
1243 if (e->GenerationBit == q->genbit) {
1244 if (e->DataValid ||
1245 process_pure_responses(adapter, e)) {
1246 if (likely(napi_schedule_prep(sge->netdev)))
1247 __netif_rx_schedule(sge->netdev);
1248 else
1249 printk(KERN_CRIT
1250 "NAPI schedule failure!\n");
1251 } else
1252 writel(q->cidx, adapter->regs + A_SG_SLEEPING);
1253 handled = 1;
1254 goto unlock;
1255 } else
1256 writel(q->cidx, adapter->regs + A_SG_SLEEPING);
1257 } else
1258 if (readl(adapter->regs + A_PL_CAUSE) & F_PL_INTR_SGE_DATA)
1259 printk(KERN_ERR "data interrupt while NAPI running\n");
1260
1261 handled = t1_slow_intr_handler(adapter);
1262 if (!handled)
1263 sge->stats.unhandled_irqs++;
1264 unlock:
1265 spin_unlock(&adapter->async_lock);
1266 return IRQ_RETVAL(handled != 0);
1267}
1268
1269/*
1270 * Main interrupt handler, optimized assuming that we took a 'DATA'
1271 * interrupt.
1272 *
1273 * 1. Clear the interrupt
1274 * 2. Loop while we find valid descriptors and process them; accumulate
1275 * information that can be processed after the loop
1276 * 3. Tell the SGE at which index we stopped processing descriptors
1277 * 4. Bookkeeping; free TX buffers, ring doorbell if there are any
1278 * outstanding TX buffers waiting, replenish RX buffers, potentially
1279 * reenable upper layers if they were turned off due to lack of TX
1280 * resources which are available again.
1281 * 5. If we took an interrupt, but no valid respQ descriptors was found we
1282 * let the slow_intr_handler run and do error handling.
1283 */
1284static irqreturn_t t1_interrupt(int irq, void *cookie, struct pt_regs *regs)
1285{
1286 int work_done;
1287 struct respQ_e *e;
1288 struct adapter *adapter = cookie;
1289 struct respQ *Q = &adapter->sge->respQ;
1290
1291 spin_lock(&adapter->async_lock);
1292 e = &Q->entries[Q->cidx];
1293 prefetch(e);
1294
1295 writel(F_PL_INTR_SGE_DATA, adapter->regs + A_PL_CAUSE);
1296
1297 if (likely(e->GenerationBit == Q->genbit))
1298 work_done = process_responses(adapter, -1);
1299 else
1300 work_done = t1_slow_intr_handler(adapter);
1301
1302 /*
1303 * The unconditional clearing of the PL_CAUSE above may have raced
1304 * with DMA completion and the corresponding generation of a response
1305 * to cause us to miss the resulting data interrupt. The next write
1306 * is also unconditional to recover the missed interrupt and render
1307 * this race harmless.
1308 */
1309 writel(Q->cidx, adapter->regs + A_SG_SLEEPING);
1310
1311 if (!work_done)
1312 adapter->sge->stats.unhandled_irqs++;
1313 spin_unlock(&adapter->async_lock);
1314 return IRQ_RETVAL(work_done != 0);
1315}
1316
1317intr_handler_t t1_select_intr_handler(adapter_t *adapter)
1318{
1319 return adapter->params.sge.polling ? t1_interrupt_napi : t1_interrupt;
1320}
1321
1322/*
1323 * Enqueues the sk_buff onto the cmdQ[qid] and has hardware fetch it.
1324 *
1325 * The code figures out how many entries the sk_buff will require in the
1326 * cmdQ and updates the cmdQ data structure with the state once the enqueue
1327 * has complete. Then, it doesn't access the global structure anymore, but
1328 * uses the corresponding fields on the stack. In conjuction with a spinlock
1329 * around that code, we can make the function reentrant without holding the
1330 * lock when we actually enqueue (which might be expensive, especially on
1331 * architectures with IO MMUs).
1332 *
1333 * This runs with softirqs disabled.
1334 */
1335unsigned int t1_sge_tx(struct sk_buff *skb, struct adapter *adapter,
1336 unsigned int qid, struct net_device *dev)
1337{
1338 struct sge *sge = adapter->sge;
1339 struct cmdQ *q = &sge->cmdQ[qid];
1340 unsigned int credits, pidx, genbit, count;
1341
1342 spin_lock(&q->lock);
1343 reclaim_completed_tx(sge, q);
1344
1345 pidx = q->pidx;
1346 credits = q->size - q->in_use;
1347 count = 1 + skb_shinfo(skb)->nr_frags;
1348
1349 { /* Ethernet packet */
1350 if (unlikely(credits < count)) {
1351 netif_stop_queue(dev);
1352 set_bit(dev->if_port, &sge->stopped_tx_queues);
1353 sge->stats.cmdQ_full[3]++;
1354 spin_unlock(&q->lock);
1355 CH_ERR("%s: Tx ring full while queue awake!\n",
1356 adapter->name);
1357 return 1;
1358 }
1359 if (unlikely(credits - count < q->stop_thres)) {
1360 sge->stats.cmdQ_full[3]++;
1361 netif_stop_queue(dev);
1362 set_bit(dev->if_port, &sge->stopped_tx_queues);
1363 }
1364 }
1365 q->in_use += count;
1366 genbit = q->genbit;
1367 q->pidx += count;
1368 if (q->pidx >= q->size) {
1369 q->pidx -= q->size;
1370 q->genbit ^= 1;
1371 }
1372 spin_unlock(&q->lock);
1373
1374 write_tx_descs(adapter, skb, pidx, genbit, q);
1375
1376 /*
1377 * We always ring the doorbell for cmdQ1. For cmdQ0, we only ring
1378 * the doorbell if the Q is asleep. There is a natural race, where
1379 * the hardware is going to sleep just after we checked, however,
1380 * then the interrupt handler will detect the outstanding TX packet
1381 * and ring the doorbell for us.
1382 */
1383 if (qid)
1384 doorbell_pio(adapter, F_CMDQ1_ENABLE);
1385 else {
1386 clear_bit(CMDQ_STAT_LAST_PKT_DB, &q->status);
1387 if (test_and_set_bit(CMDQ_STAT_RUNNING, &q->status) == 0) {
1388 set_bit(CMDQ_STAT_LAST_PKT_DB, &q->status);
1389 writel(F_CMDQ0_ENABLE, adapter->regs + A_SG_DOORBELL);
1390 }
1391 }
1392 return 0;
1393}
1394
1395#define MK_ETH_TYPE_MSS(type, mss) (((mss) & 0x3FFF) | ((type) << 14))
1396
1397/*
1398 * eth_hdr_len - return the length of an Ethernet header
1399 * @data: pointer to the start of the Ethernet header
1400 *
1401 * Returns the length of an Ethernet header, including optional VLAN tag.
1402 */
1403static inline int eth_hdr_len(const void *data)
1404{
1405 const struct ethhdr *e = data;
1406
1407 return e->h_proto == htons(ETH_P_8021Q) ? VLAN_ETH_HLEN : ETH_HLEN;
1408}
1409
1410/*
1411 * Adds the CPL header to the sk_buff and passes it to t1_sge_tx.
1412 */
1413int t1_start_xmit(struct sk_buff *skb, struct net_device *dev)
1414{
1415 struct adapter *adapter = dev->priv;
1416 struct sge_port_stats *st = &adapter->sge->port_stats[dev->if_port];
1417 struct sge *sge = adapter->sge;
1418 struct cpl_tx_pkt *cpl;
1419
1420#ifdef NETIF_F_TSO
1421 if (skb_shinfo(skb)->tso_size) {
1422 int eth_type;
1423 struct cpl_tx_pkt_lso *hdr;
1424
1425 st->tso++;
1426
1427 eth_type = skb->nh.raw - skb->data == ETH_HLEN ?
1428 CPL_ETH_II : CPL_ETH_II_VLAN;
1429
1430 hdr = (struct cpl_tx_pkt_lso *)skb_push(skb, sizeof(*hdr));
1431 hdr->opcode = CPL_TX_PKT_LSO;
1432 hdr->ip_csum_dis = hdr->l4_csum_dis = 0;
1433 hdr->ip_hdr_words = skb->nh.iph->ihl;
1434 hdr->tcp_hdr_words = skb->h.th->doff;
1435 hdr->eth_type_mss = htons(MK_ETH_TYPE_MSS(eth_type,
1436 skb_shinfo(skb)->tso_size));
1437 hdr->len = htonl(skb->len - sizeof(*hdr));
1438 cpl = (struct cpl_tx_pkt *)hdr;
1439 sge->stats.tx_lso_pkts++;
1440 } else
1441#endif
1442 {
1443 /*
1444 * Packets shorter than ETH_HLEN can break the MAC, drop them
1445 * early. Also, we may get oversized packets because some
1446 * parts of the kernel don't handle our unusual hard_header_len
1447 * right, drop those too.
1448 */
1449 if (unlikely(skb->len < ETH_HLEN ||
1450 skb->len > dev->mtu + eth_hdr_len(skb->data))) {
1451 dev_kfree_skb_any(skb);
1452 return NET_XMIT_SUCCESS;
1453 }
1454
1455 /*
1456 * We are using a non-standard hard_header_len and some kernel
1457 * components, such as pktgen, do not handle it right.
1458 * Complain when this happens but try to fix things up.
1459 */
1460 if (unlikely(skb_headroom(skb) <
1461 dev->hard_header_len - ETH_HLEN)) {
1462 struct sk_buff *orig_skb = skb;
1463
1464 if (net_ratelimit())
1465 printk(KERN_ERR "%s: inadequate headroom in "
1466 "Tx packet\n", dev->name);
1467 skb = skb_realloc_headroom(skb, sizeof(*cpl));
1468 dev_kfree_skb_any(orig_skb);
1469 if (!skb)
1470 return -ENOMEM;
1471 }
1472
1473 if (!(adapter->flags & UDP_CSUM_CAPABLE) &&
1474 skb->ip_summed == CHECKSUM_HW &&
1475 skb->nh.iph->protocol == IPPROTO_UDP)
1476 if (unlikely(skb_checksum_help(skb, 0))) {
1477 dev_kfree_skb_any(skb);
1478 return -ENOMEM;
1479 }
1480
1481 /* Hmmm, assuming to catch the gratious arp... and we'll use
1482 * it to flush out stuck espi packets...
1483 */
1484 if (unlikely(!adapter->sge->espibug_skb)) {
1485 if (skb->protocol == htons(ETH_P_ARP) &&
1486 skb->nh.arph->ar_op == htons(ARPOP_REQUEST)) {
1487 adapter->sge->espibug_skb = skb;
1488 /* We want to re-use this skb later. We
1489 * simply bump the reference count and it
1490 * will not be freed...
1491 */
1492 skb = skb_get(skb);
1493 }
1494 }
1495
1496 cpl = (struct cpl_tx_pkt *)__skb_push(skb, sizeof(*cpl));
1497 cpl->opcode = CPL_TX_PKT;
1498 cpl->ip_csum_dis = 1; /* SW calculates IP csum */
1499 cpl->l4_csum_dis = skb->ip_summed == CHECKSUM_HW ? 0 : 1;
1500 /* the length field isn't used so don't bother setting it */
1501
1502 st->tx_cso += (skb->ip_summed == CHECKSUM_HW);
1503 sge->stats.tx_do_cksum += (skb->ip_summed == CHECKSUM_HW);
1504 sge->stats.tx_reg_pkts++;
1505 }
1506 cpl->iff = dev->if_port;
1507
1508#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
1509 if (adapter->vlan_grp && vlan_tx_tag_present(skb)) {
1510 cpl->vlan_valid = 1;
1511 cpl->vlan = htons(vlan_tx_tag_get(skb));
1512 st->vlan_insert++;
1513 } else
1514#endif
1515 cpl->vlan_valid = 0;
1516
1517 dev->trans_start = jiffies;
1518 return t1_sge_tx(skb, adapter, 0, dev);
1519}
1520
1521/*
1522 * Callback for the Tx buffer reclaim timer. Runs with softirqs disabled.
1523 */
1524static void sge_tx_reclaim_cb(unsigned long data)
1525{
1526 int i;
1527 struct sge *sge = (struct sge *)data;
1528
1529 for (i = 0; i < SGE_CMDQ_N; ++i) {
1530 struct cmdQ *q = &sge->cmdQ[i];
1531
1532 if (!spin_trylock(&q->lock))
1533 continue;
1534
1535 reclaim_completed_tx(sge, q);
1536 if (i == 0 && q->in_use) /* flush pending credits */
1537 writel(F_CMDQ0_ENABLE,
1538 sge->adapter->regs + A_SG_DOORBELL);
1539
1540 spin_unlock(&q->lock);
1541 }
1542 mod_timer(&sge->tx_reclaim_timer, jiffies + TX_RECLAIM_PERIOD);
1543}
1544
1545/*
1546 * Propagate changes of the SGE coalescing parameters to the HW.
1547 */
1548int t1_sge_set_coalesce_params(struct sge *sge, struct sge_params *p)
1549{
1550 sge->netdev->poll = t1_poll;
1551 sge->fixed_intrtimer = p->rx_coalesce_usecs *
1552 core_ticks_per_usec(sge->adapter);
1553 writel(sge->fixed_intrtimer, sge->adapter->regs + A_SG_INTRTIMER);
1554 return 0;
1555}
1556
1557/*
1558 * Allocates both RX and TX resources and configures the SGE. However,
1559 * the hardware is not enabled yet.
1560 */
1561int t1_sge_configure(struct sge *sge, struct sge_params *p)
1562{
1563 if (alloc_rx_resources(sge, p))
1564 return -ENOMEM;
1565 if (alloc_tx_resources(sge, p)) {
1566 free_rx_resources(sge);
1567 return -ENOMEM;
1568 }
1569 configure_sge(sge, p);
1570
1571 /*
1572 * Now that we have sized the free lists calculate the payload
1573 * capacity of the large buffers. Other parts of the driver use
1574 * this to set the max offload coalescing size so that RX packets
1575 * do not overflow our large buffers.
1576 */
1577 p->large_buf_capacity = jumbo_payload_capacity(sge);
1578 return 0;
1579}
1580
1581/*
1582 * Disables the DMA engine.
1583 */
1584void t1_sge_stop(struct sge *sge)
1585{
1586 writel(0, sge->adapter->regs + A_SG_CONTROL);
1587 (void) readl(sge->adapter->regs + A_SG_CONTROL); /* flush */
1588 if (is_T2(sge->adapter))
1589 del_timer_sync(&sge->espibug_timer);
1590 del_timer_sync(&sge->tx_reclaim_timer);
1591}
1592
1593/*
1594 * Enables the DMA engine.
1595 */
1596void t1_sge_start(struct sge *sge)
1597{
1598 refill_free_list(sge, &sge->freelQ[0]);
1599 refill_free_list(sge, &sge->freelQ[1]);
1600
1601 writel(sge->sge_control, sge->adapter->regs + A_SG_CONTROL);
1602 doorbell_pio(sge->adapter, F_FL0_ENABLE | F_FL1_ENABLE);
1603 (void) readl(sge->adapter->regs + A_SG_CONTROL); /* flush */
1604
1605 mod_timer(&sge->tx_reclaim_timer, jiffies + TX_RECLAIM_PERIOD);
1606
1607 if (is_T2(sge->adapter))
1608 mod_timer(&sge->espibug_timer, jiffies + sge->espibug_timeout);
1609}
1610
1611/*
1612 * Callback for the T2 ESPI 'stuck packet feature' workaorund
1613 */
1614static void espibug_workaround(void *data)
1615{
1616 struct adapter *adapter = (struct adapter *)data;
1617 struct sge *sge = adapter->sge;
1618
1619 if (netif_running(adapter->port[0].dev)) {
1620 struct sk_buff *skb = sge->espibug_skb;
1621
1622 u32 seop = t1_espi_get_mon(adapter, 0x930, 0);
1623
1624 if ((seop & 0xfff0fff) == 0xfff && skb) {
1625 if (!skb->cb[0]) {
1626 u8 ch_mac_addr[ETH_ALEN] =
1627 {0x0, 0x7, 0x43, 0x0, 0x0, 0x0};
1628 memcpy(skb->data + sizeof(struct cpl_tx_pkt),
1629 ch_mac_addr, ETH_ALEN);
1630 memcpy(skb->data + skb->len - 10, ch_mac_addr,
1631 ETH_ALEN);
1632 skb->cb[0] = 0xff;
1633 }
1634
1635 /* bump the reference count to avoid freeing of the
1636 * skb once the DMA has completed.
1637 */
1638 skb = skb_get(skb);
1639 t1_sge_tx(skb, adapter, 0, adapter->port[0].dev);
1640 }
1641 }
1642 mod_timer(&sge->espibug_timer, jiffies + sge->espibug_timeout);
1643}
1644
1645/*
1646 * Creates a t1_sge structure and returns suggested resource parameters.
1647 */
1648struct sge * __devinit t1_sge_create(struct adapter *adapter,
1649 struct sge_params *p)
1650{
1651 struct sge *sge = kmalloc(sizeof(*sge), GFP_KERNEL);
1652
1653 if (!sge)
1654 return NULL;
1655 memset(sge, 0, sizeof(*sge));
1656
1657 sge->adapter = adapter;
1658 sge->netdev = adapter->port[0].dev;
1659 sge->rx_pkt_pad = t1_is_T1B(adapter) ? 0 : 2;
1660 sge->jumbo_fl = t1_is_T1B(adapter) ? 1 : 0;
1661
1662 init_timer(&sge->tx_reclaim_timer);
1663 sge->tx_reclaim_timer.data = (unsigned long)sge;
1664 sge->tx_reclaim_timer.function = sge_tx_reclaim_cb;
1665
1666 if (is_T2(sge->adapter)) {
1667 init_timer(&sge->espibug_timer);
1668 sge->espibug_timer.function = (void *)&espibug_workaround;
1669 sge->espibug_timer.data = (unsigned long)sge->adapter;
1670 sge->espibug_timeout = 1;
1671 }
1672
1673
1674 p->cmdQ_size[0] = SGE_CMDQ0_E_N;
1675 p->cmdQ_size[1] = SGE_CMDQ1_E_N;
1676 p->freelQ_size[!sge->jumbo_fl] = SGE_FREEL_SIZE;
1677 p->freelQ_size[sge->jumbo_fl] = SGE_JUMBO_FREEL_SIZE;
1678 p->rx_coalesce_usecs = 50;
1679 p->coalesce_enable = 0;
1680 p->sample_interval_usecs = 0;
1681 p->polling = 0;
1682
1683 return sge;
1684}
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-11 00:05:21 -0500