1 /****************************************************************************
2  * Driver for Solarflare Solarstorm network controllers and boards
3  * Copyright 2005-2006 Fen Systems Ltd.
4  * Copyright 2006-2011 Solarflare Communications Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published
8  * by the Free Software Foundation, incorporated herein by reference.
9  */
10 
11 #include <linux/bitops.h>
12 #include <linux/delay.h>
13 #include <linux/pci.h>
14 #include <linux/module.h>
15 #include <linux/seq_file.h>
16 #include "net_driver.h"
17 #include "bitfield.h"
18 #include "efx.h"
19 #include "nic.h"
20 #include "regs.h"
21 #include "io.h"
22 #include "workarounds.h"
23 
24 /**************************************************************************
25  *
26  * Configurable values
27  *
28  **************************************************************************
29  */
30 
31 /* This is set to 16 for a good reason.  In summary, if larger than
32  * 16, the descriptor cache holds more than a default socket
33  * buffer's worth of packets (for UDP we can only have at most one
34  * socket buffer's worth outstanding).  This combined with the fact
35  * that we only get 1 TX event per descriptor cache means the NIC
36  * goes idle.
37  */
38 #define TX_DC_ENTRIES 16
39 #define TX_DC_ENTRIES_ORDER 1
40 
41 #define RX_DC_ENTRIES 64
42 #define RX_DC_ENTRIES_ORDER 3
43 
44 /* If EFX_MAX_INT_ERRORS internal errors occur within
45  * EFX_INT_ERROR_EXPIRE seconds, we consider the NIC broken and
46  * disable it.
47  */
48 #define EFX_INT_ERROR_EXPIRE 3600
49 #define EFX_MAX_INT_ERRORS 5
50 
51 /* We poll for events every FLUSH_INTERVAL ms, and check FLUSH_POLL_COUNT times
52  */
53 #define EFX_FLUSH_INTERVAL 10
54 #define EFX_FLUSH_POLL_COUNT 100
55 
56 /* Size and alignment of special buffers (4KB) */
57 #define EFX_BUF_SIZE 4096
58 
59 /* Depth of RX flush request fifo */
60 #define EFX_RX_FLUSH_COUNT 4
61 
62 /* Generated event code for efx_generate_test_event() */
63 #define EFX_CHANNEL_MAGIC_TEST(_channel)	\
64 	(0x00010100 + (_channel)->channel)
65 
66 /* Generated event code for efx_generate_fill_event() */
67 #define EFX_CHANNEL_MAGIC_FILL(_channel)	\
68 	(0x00010200 + (_channel)->channel)
69 
70 /**************************************************************************
71  *
72  * Solarstorm hardware access
73  *
74  **************************************************************************/
75 
efx_write_buf_tbl(struct efx_nic * efx,efx_qword_t * value,unsigned int index)76 static inline void efx_write_buf_tbl(struct efx_nic *efx, efx_qword_t *value,
77 				     unsigned int index)
78 {
79 	efx_sram_writeq(efx, efx->membase + efx->type->buf_tbl_base,
80 			value, index);
81 }
82 
83 /* Read the current event from the event queue */
efx_event(struct efx_channel * channel,unsigned int index)84 static inline efx_qword_t *efx_event(struct efx_channel *channel,
85 				     unsigned int index)
86 {
87 	return ((efx_qword_t *) (channel->eventq.addr)) +
88 		(index & channel->eventq_mask);
89 }
90 
91 /* See if an event is present
92  *
93  * We check both the high and low dword of the event for all ones.  We
94  * wrote all ones when we cleared the event, and no valid event can
95  * have all ones in either its high or low dwords.  This approach is
96  * robust against reordering.
97  *
98  * Note that using a single 64-bit comparison is incorrect; even
99  * though the CPU read will be atomic, the DMA write may not be.
100  */
efx_event_present(efx_qword_t * event)101 static inline int efx_event_present(efx_qword_t *event)
102 {
103 	return !(EFX_DWORD_IS_ALL_ONES(event->dword[0]) |
104 		  EFX_DWORD_IS_ALL_ONES(event->dword[1]));
105 }
106 
efx_masked_compare_oword(const efx_oword_t * a,const efx_oword_t * b,const efx_oword_t * mask)107 static bool efx_masked_compare_oword(const efx_oword_t *a, const efx_oword_t *b,
108 				     const efx_oword_t *mask)
109 {
110 	return ((a->u64[0] ^ b->u64[0]) & mask->u64[0]) ||
111 		((a->u64[1] ^ b->u64[1]) & mask->u64[1]);
112 }
113 
efx_nic_test_registers(struct efx_nic * efx,const struct efx_nic_register_test * regs,size_t n_regs)114 int efx_nic_test_registers(struct efx_nic *efx,
115 			   const struct efx_nic_register_test *regs,
116 			   size_t n_regs)
117 {
118 	unsigned address = 0, i, j;
119 	efx_oword_t mask, imask, original, reg, buf;
120 
121 	/* Falcon should be in loopback to isolate the XMAC from the PHY */
122 	WARN_ON(!LOOPBACK_INTERNAL(efx));
123 
124 	for (i = 0; i < n_regs; ++i) {
125 		address = regs[i].address;
126 		mask = imask = regs[i].mask;
127 		EFX_INVERT_OWORD(imask);
128 
129 		efx_reado(efx, &original, address);
130 
131 		/* bit sweep on and off */
132 		for (j = 0; j < 128; j++) {
133 			if (!EFX_EXTRACT_OWORD32(mask, j, j))
134 				continue;
135 
136 			/* Test this testable bit can be set in isolation */
137 			EFX_AND_OWORD(reg, original, mask);
138 			EFX_SET_OWORD32(reg, j, j, 1);
139 
140 			efx_writeo(efx, &reg, address);
141 			efx_reado(efx, &buf, address);
142 
143 			if (efx_masked_compare_oword(&reg, &buf, &mask))
144 				goto fail;
145 
146 			/* Test this testable bit can be cleared in isolation */
147 			EFX_OR_OWORD(reg, original, mask);
148 			EFX_SET_OWORD32(reg, j, j, 0);
149 
150 			efx_writeo(efx, &reg, address);
151 			efx_reado(efx, &buf, address);
152 
153 			if (efx_masked_compare_oword(&reg, &buf, &mask))
154 				goto fail;
155 		}
156 
157 		efx_writeo(efx, &original, address);
158 	}
159 
160 	return 0;
161 
162 fail:
163 	netif_err(efx, hw, efx->net_dev,
164 		  "wrote "EFX_OWORD_FMT" read "EFX_OWORD_FMT
165 		  " at address 0x%x mask "EFX_OWORD_FMT"\n", EFX_OWORD_VAL(reg),
166 		  EFX_OWORD_VAL(buf), address, EFX_OWORD_VAL(mask));
167 	return -EIO;
168 }
169 
170 /**************************************************************************
171  *
172  * Special buffer handling
173  * Special buffers are used for event queues and the TX and RX
174  * descriptor rings.
175  *
176  *************************************************************************/
177 
178 /*
179  * Initialise a special buffer
180  *
181  * This will define a buffer (previously allocated via
182  * efx_alloc_special_buffer()) in the buffer table, allowing
183  * it to be used for event queues, descriptor rings etc.
184  */
185 static void
efx_init_special_buffer(struct efx_nic * efx,struct efx_special_buffer * buffer)186 efx_init_special_buffer(struct efx_nic *efx, struct efx_special_buffer *buffer)
187 {
188 	efx_qword_t buf_desc;
189 	int index;
190 	dma_addr_t dma_addr;
191 	int i;
192 
193 	EFX_BUG_ON_PARANOID(!buffer->addr);
194 
195 	/* Write buffer descriptors to NIC */
196 	for (i = 0; i < buffer->entries; i++) {
197 		index = buffer->index + i;
198 		dma_addr = buffer->dma_addr + (i * 4096);
199 		netif_dbg(efx, probe, efx->net_dev,
200 			  "mapping special buffer %d at %llx\n",
201 			  index, (unsigned long long)dma_addr);
202 		EFX_POPULATE_QWORD_3(buf_desc,
203 				     FRF_AZ_BUF_ADR_REGION, 0,
204 				     FRF_AZ_BUF_ADR_FBUF, dma_addr >> 12,
205 				     FRF_AZ_BUF_OWNER_ID_FBUF, 0);
206 		efx_write_buf_tbl(efx, &buf_desc, index);
207 	}
208 }
209 
210 /* Unmaps a buffer and clears the buffer table entries */
211 static void
efx_fini_special_buffer(struct efx_nic * efx,struct efx_special_buffer * buffer)212 efx_fini_special_buffer(struct efx_nic *efx, struct efx_special_buffer *buffer)
213 {
214 	efx_oword_t buf_tbl_upd;
215 	unsigned int start = buffer->index;
216 	unsigned int end = (buffer->index + buffer->entries - 1);
217 
218 	if (!buffer->entries)
219 		return;
220 
221 	netif_dbg(efx, hw, efx->net_dev, "unmapping special buffers %d-%d\n",
222 		  buffer->index, buffer->index + buffer->entries - 1);
223 
224 	EFX_POPULATE_OWORD_4(buf_tbl_upd,
225 			     FRF_AZ_BUF_UPD_CMD, 0,
226 			     FRF_AZ_BUF_CLR_CMD, 1,
227 			     FRF_AZ_BUF_CLR_END_ID, end,
228 			     FRF_AZ_BUF_CLR_START_ID, start);
229 	efx_writeo(efx, &buf_tbl_upd, FR_AZ_BUF_TBL_UPD);
230 }
231 
232 /*
233  * Allocate a new special buffer
234  *
235  * This allocates memory for a new buffer, clears it and allocates a
236  * new buffer ID range.  It does not write into the buffer table.
237  *
238  * This call will allocate 4KB buffers, since 8KB buffers can't be
239  * used for event queues and descriptor rings.
240  */
efx_alloc_special_buffer(struct efx_nic * efx,struct efx_special_buffer * buffer,unsigned int len)241 static int efx_alloc_special_buffer(struct efx_nic *efx,
242 				    struct efx_special_buffer *buffer,
243 				    unsigned int len)
244 {
245 	len = ALIGN(len, EFX_BUF_SIZE);
246 
247 	buffer->addr = dma_alloc_coherent(&efx->pci_dev->dev, len,
248 					  &buffer->dma_addr, GFP_KERNEL);
249 	if (!buffer->addr)
250 		return -ENOMEM;
251 	buffer->len = len;
252 	buffer->entries = len / EFX_BUF_SIZE;
253 	BUG_ON(buffer->dma_addr & (EFX_BUF_SIZE - 1));
254 
255 	/* All zeros is a potentially valid event so memset to 0xff */
256 	memset(buffer->addr, 0xff, len);
257 
258 	/* Select new buffer ID */
259 	buffer->index = efx->next_buffer_table;
260 	efx->next_buffer_table += buffer->entries;
261 
262 	netif_dbg(efx, probe, efx->net_dev,
263 		  "allocating special buffers %d-%d at %llx+%x "
264 		  "(virt %p phys %llx)\n", buffer->index,
265 		  buffer->index + buffer->entries - 1,
266 		  (u64)buffer->dma_addr, len,
267 		  buffer->addr, (u64)virt_to_phys(buffer->addr));
268 
269 	return 0;
270 }
271 
272 static void
efx_free_special_buffer(struct efx_nic * efx,struct efx_special_buffer * buffer)273 efx_free_special_buffer(struct efx_nic *efx, struct efx_special_buffer *buffer)
274 {
275 	if (!buffer->addr)
276 		return;
277 
278 	netif_dbg(efx, hw, efx->net_dev,
279 		  "deallocating special buffers %d-%d at %llx+%x "
280 		  "(virt %p phys %llx)\n", buffer->index,
281 		  buffer->index + buffer->entries - 1,
282 		  (u64)buffer->dma_addr, buffer->len,
283 		  buffer->addr, (u64)virt_to_phys(buffer->addr));
284 
285 	dma_free_coherent(&efx->pci_dev->dev, buffer->len, buffer->addr,
286 			  buffer->dma_addr);
287 	buffer->addr = NULL;
288 	buffer->entries = 0;
289 }
290 
291 /**************************************************************************
292  *
293  * Generic buffer handling
294  * These buffers are used for interrupt status and MAC stats
295  *
296  **************************************************************************/
297 
efx_nic_alloc_buffer(struct efx_nic * efx,struct efx_buffer * buffer,unsigned int len)298 int efx_nic_alloc_buffer(struct efx_nic *efx, struct efx_buffer *buffer,
299 			 unsigned int len)
300 {
301 	buffer->addr = pci_alloc_consistent(efx->pci_dev, len,
302 					    &buffer->dma_addr);
303 	if (!buffer->addr)
304 		return -ENOMEM;
305 	buffer->len = len;
306 	memset(buffer->addr, 0, len);
307 	return 0;
308 }
309 
efx_nic_free_buffer(struct efx_nic * efx,struct efx_buffer * buffer)310 void efx_nic_free_buffer(struct efx_nic *efx, struct efx_buffer *buffer)
311 {
312 	if (buffer->addr) {
313 		pci_free_consistent(efx->pci_dev, buffer->len,
314 				    buffer->addr, buffer->dma_addr);
315 		buffer->addr = NULL;
316 	}
317 }
318 
319 /**************************************************************************
320  *
321  * TX path
322  *
323  **************************************************************************/
324 
325 /* Returns a pointer to the specified transmit descriptor in the TX
326  * descriptor queue belonging to the specified channel.
327  */
328 static inline efx_qword_t *
efx_tx_desc(struct efx_tx_queue * tx_queue,unsigned int index)329 efx_tx_desc(struct efx_tx_queue *tx_queue, unsigned int index)
330 {
331 	return ((efx_qword_t *) (tx_queue->txd.addr)) + index;
332 }
333 
334 /* This writes to the TX_DESC_WPTR; write pointer for TX descriptor ring */
efx_notify_tx_desc(struct efx_tx_queue * tx_queue)335 static inline void efx_notify_tx_desc(struct efx_tx_queue *tx_queue)
336 {
337 	unsigned write_ptr;
338 	efx_dword_t reg;
339 
340 	write_ptr = tx_queue->write_count & tx_queue->ptr_mask;
341 	EFX_POPULATE_DWORD_1(reg, FRF_AZ_TX_DESC_WPTR_DWORD, write_ptr);
342 	efx_writed_page(tx_queue->efx, &reg,
343 			FR_AZ_TX_DESC_UPD_DWORD_P0, tx_queue->queue);
344 }
345 
346 /* Write pointer and first descriptor for TX descriptor ring */
efx_push_tx_desc(struct efx_tx_queue * tx_queue,const efx_qword_t * txd)347 static inline void efx_push_tx_desc(struct efx_tx_queue *tx_queue,
348 				    const efx_qword_t *txd)
349 {
350 	unsigned write_ptr;
351 	efx_oword_t reg;
352 
353 	BUILD_BUG_ON(FRF_AZ_TX_DESC_LBN != 0);
354 	BUILD_BUG_ON(FR_AA_TX_DESC_UPD_KER != FR_BZ_TX_DESC_UPD_P0);
355 
356 	write_ptr = tx_queue->write_count & tx_queue->ptr_mask;
357 	EFX_POPULATE_OWORD_2(reg, FRF_AZ_TX_DESC_PUSH_CMD, true,
358 			     FRF_AZ_TX_DESC_WPTR, write_ptr);
359 	reg.qword[0] = *txd;
360 	efx_writeo_page(tx_queue->efx, &reg,
361 			FR_BZ_TX_DESC_UPD_P0, tx_queue->queue);
362 }
363 
364 static inline bool
efx_may_push_tx_desc(struct efx_tx_queue * tx_queue,unsigned int write_count)365 efx_may_push_tx_desc(struct efx_tx_queue *tx_queue, unsigned int write_count)
366 {
367 	unsigned empty_read_count = ACCESS_ONCE(tx_queue->empty_read_count);
368 
369 	if (empty_read_count == 0)
370 		return false;
371 
372 	tx_queue->empty_read_count = 0;
373 	return ((empty_read_count ^ write_count) & ~EFX_EMPTY_COUNT_VALID) == 0;
374 }
375 
376 /* For each entry inserted into the software descriptor ring, create a
377  * descriptor in the hardware TX descriptor ring (in host memory), and
378  * write a doorbell.
379  */
efx_nic_push_buffers(struct efx_tx_queue * tx_queue)380 void efx_nic_push_buffers(struct efx_tx_queue *tx_queue)
381 {
382 
383 	struct efx_tx_buffer *buffer;
384 	efx_qword_t *txd;
385 	unsigned write_ptr;
386 	unsigned old_write_count = tx_queue->write_count;
387 
388 	BUG_ON(tx_queue->write_count == tx_queue->insert_count);
389 
390 	do {
391 		write_ptr = tx_queue->write_count & tx_queue->ptr_mask;
392 		buffer = &tx_queue->buffer[write_ptr];
393 		txd = efx_tx_desc(tx_queue, write_ptr);
394 		++tx_queue->write_count;
395 
396 		/* Create TX descriptor ring entry */
397 		EFX_POPULATE_QWORD_4(*txd,
398 				     FSF_AZ_TX_KER_CONT, buffer->continuation,
399 				     FSF_AZ_TX_KER_BYTE_COUNT, buffer->len,
400 				     FSF_AZ_TX_KER_BUF_REGION, 0,
401 				     FSF_AZ_TX_KER_BUF_ADDR, buffer->dma_addr);
402 	} while (tx_queue->write_count != tx_queue->insert_count);
403 
404 	wmb(); /* Ensure descriptors are written before they are fetched */
405 
406 	if (efx_may_push_tx_desc(tx_queue, old_write_count)) {
407 		txd = efx_tx_desc(tx_queue,
408 				  old_write_count & tx_queue->ptr_mask);
409 		efx_push_tx_desc(tx_queue, txd);
410 		++tx_queue->pushes;
411 	} else {
412 		efx_notify_tx_desc(tx_queue);
413 	}
414 }
415 
416 /* Allocate hardware resources for a TX queue */
efx_nic_probe_tx(struct efx_tx_queue * tx_queue)417 int efx_nic_probe_tx(struct efx_tx_queue *tx_queue)
418 {
419 	struct efx_nic *efx = tx_queue->efx;
420 	unsigned entries;
421 
422 	entries = tx_queue->ptr_mask + 1;
423 	return efx_alloc_special_buffer(efx, &tx_queue->txd,
424 					entries * sizeof(efx_qword_t));
425 }
426 
efx_nic_init_tx(struct efx_tx_queue * tx_queue)427 void efx_nic_init_tx(struct efx_tx_queue *tx_queue)
428 {
429 	struct efx_nic *efx = tx_queue->efx;
430 	efx_oword_t reg;
431 
432 	tx_queue->flushed = FLUSH_NONE;
433 
434 	/* Pin TX descriptor ring */
435 	efx_init_special_buffer(efx, &tx_queue->txd);
436 
437 	/* Push TX descriptor ring to card */
438 	EFX_POPULATE_OWORD_10(reg,
439 			      FRF_AZ_TX_DESCQ_EN, 1,
440 			      FRF_AZ_TX_ISCSI_DDIG_EN, 0,
441 			      FRF_AZ_TX_ISCSI_HDIG_EN, 0,
442 			      FRF_AZ_TX_DESCQ_BUF_BASE_ID, tx_queue->txd.index,
443 			      FRF_AZ_TX_DESCQ_EVQ_ID,
444 			      tx_queue->channel->channel,
445 			      FRF_AZ_TX_DESCQ_OWNER_ID, 0,
446 			      FRF_AZ_TX_DESCQ_LABEL, tx_queue->queue,
447 			      FRF_AZ_TX_DESCQ_SIZE,
448 			      __ffs(tx_queue->txd.entries),
449 			      FRF_AZ_TX_DESCQ_TYPE, 0,
450 			      FRF_BZ_TX_NON_IP_DROP_DIS, 1);
451 
452 	if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0) {
453 		int csum = tx_queue->queue & EFX_TXQ_TYPE_OFFLOAD;
454 		EFX_SET_OWORD_FIELD(reg, FRF_BZ_TX_IP_CHKSM_DIS, !csum);
455 		EFX_SET_OWORD_FIELD(reg, FRF_BZ_TX_TCP_CHKSM_DIS,
456 				    !csum);
457 	}
458 
459 	efx_writeo_table(efx, &reg, efx->type->txd_ptr_tbl_base,
460 			 tx_queue->queue);
461 
462 	if (efx_nic_rev(efx) < EFX_REV_FALCON_B0) {
463 		/* Only 128 bits in this register */
464 		BUILD_BUG_ON(EFX_MAX_TX_QUEUES > 128);
465 
466 		efx_reado(efx, &reg, FR_AA_TX_CHKSM_CFG);
467 		if (tx_queue->queue & EFX_TXQ_TYPE_OFFLOAD)
468 			clear_bit_le(tx_queue->queue, (void *)&reg);
469 		else
470 			set_bit_le(tx_queue->queue, (void *)&reg);
471 		efx_writeo(efx, &reg, FR_AA_TX_CHKSM_CFG);
472 	}
473 
474 	if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0) {
475 		EFX_POPULATE_OWORD_1(reg,
476 				     FRF_BZ_TX_PACE,
477 				     (tx_queue->queue & EFX_TXQ_TYPE_HIGHPRI) ?
478 				     FFE_BZ_TX_PACE_OFF :
479 				     FFE_BZ_TX_PACE_RESERVED);
480 		efx_writeo_table(efx, &reg, FR_BZ_TX_PACE_TBL,
481 				 tx_queue->queue);
482 	}
483 }
484 
efx_flush_tx_queue(struct efx_tx_queue * tx_queue)485 static void efx_flush_tx_queue(struct efx_tx_queue *tx_queue)
486 {
487 	struct efx_nic *efx = tx_queue->efx;
488 	efx_oword_t tx_flush_descq;
489 
490 	tx_queue->flushed = FLUSH_PENDING;
491 
492 	/* Post a flush command */
493 	EFX_POPULATE_OWORD_2(tx_flush_descq,
494 			     FRF_AZ_TX_FLUSH_DESCQ_CMD, 1,
495 			     FRF_AZ_TX_FLUSH_DESCQ, tx_queue->queue);
496 	efx_writeo(efx, &tx_flush_descq, FR_AZ_TX_FLUSH_DESCQ);
497 }
498 
efx_nic_fini_tx(struct efx_tx_queue * tx_queue)499 void efx_nic_fini_tx(struct efx_tx_queue *tx_queue)
500 {
501 	struct efx_nic *efx = tx_queue->efx;
502 	efx_oword_t tx_desc_ptr;
503 
504 	/* The queue should have been flushed */
505 	WARN_ON(tx_queue->flushed != FLUSH_DONE);
506 
507 	/* Remove TX descriptor ring from card */
508 	EFX_ZERO_OWORD(tx_desc_ptr);
509 	efx_writeo_table(efx, &tx_desc_ptr, efx->type->txd_ptr_tbl_base,
510 			 tx_queue->queue);
511 
512 	/* Unpin TX descriptor ring */
513 	efx_fini_special_buffer(efx, &tx_queue->txd);
514 }
515 
516 /* Free buffers backing TX queue */
efx_nic_remove_tx(struct efx_tx_queue * tx_queue)517 void efx_nic_remove_tx(struct efx_tx_queue *tx_queue)
518 {
519 	efx_free_special_buffer(tx_queue->efx, &tx_queue->txd);
520 }
521 
522 /**************************************************************************
523  *
524  * RX path
525  *
526  **************************************************************************/
527 
528 /* Returns a pointer to the specified descriptor in the RX descriptor queue */
529 static inline efx_qword_t *
efx_rx_desc(struct efx_rx_queue * rx_queue,unsigned int index)530 efx_rx_desc(struct efx_rx_queue *rx_queue, unsigned int index)
531 {
532 	return ((efx_qword_t *) (rx_queue->rxd.addr)) + index;
533 }
534 
535 /* This creates an entry in the RX descriptor queue */
536 static inline void
efx_build_rx_desc(struct efx_rx_queue * rx_queue,unsigned index)537 efx_build_rx_desc(struct efx_rx_queue *rx_queue, unsigned index)
538 {
539 	struct efx_rx_buffer *rx_buf;
540 	efx_qword_t *rxd;
541 
542 	rxd = efx_rx_desc(rx_queue, index);
543 	rx_buf = efx_rx_buffer(rx_queue, index);
544 	EFX_POPULATE_QWORD_3(*rxd,
545 			     FSF_AZ_RX_KER_BUF_SIZE,
546 			     rx_buf->len -
547 			     rx_queue->efx->type->rx_buffer_padding,
548 			     FSF_AZ_RX_KER_BUF_REGION, 0,
549 			     FSF_AZ_RX_KER_BUF_ADDR, rx_buf->dma_addr);
550 }
551 
552 /* This writes to the RX_DESC_WPTR register for the specified receive
553  * descriptor ring.
554  */
efx_nic_notify_rx_desc(struct efx_rx_queue * rx_queue)555 void efx_nic_notify_rx_desc(struct efx_rx_queue *rx_queue)
556 {
557 	struct efx_nic *efx = rx_queue->efx;
558 	efx_dword_t reg;
559 	unsigned write_ptr;
560 
561 	while (rx_queue->notified_count != rx_queue->added_count) {
562 		efx_build_rx_desc(
563 			rx_queue,
564 			rx_queue->notified_count & rx_queue->ptr_mask);
565 		++rx_queue->notified_count;
566 	}
567 
568 	wmb();
569 	write_ptr = rx_queue->added_count & rx_queue->ptr_mask;
570 	EFX_POPULATE_DWORD_1(reg, FRF_AZ_RX_DESC_WPTR_DWORD, write_ptr);
571 	efx_writed_page(efx, &reg, FR_AZ_RX_DESC_UPD_DWORD_P0,
572 			efx_rx_queue_index(rx_queue));
573 }
574 
efx_nic_probe_rx(struct efx_rx_queue * rx_queue)575 int efx_nic_probe_rx(struct efx_rx_queue *rx_queue)
576 {
577 	struct efx_nic *efx = rx_queue->efx;
578 	unsigned entries;
579 
580 	entries = rx_queue->ptr_mask + 1;
581 	return efx_alloc_special_buffer(efx, &rx_queue->rxd,
582 					entries * sizeof(efx_qword_t));
583 }
584 
efx_nic_init_rx(struct efx_rx_queue * rx_queue)585 void efx_nic_init_rx(struct efx_rx_queue *rx_queue)
586 {
587 	efx_oword_t rx_desc_ptr;
588 	struct efx_nic *efx = rx_queue->efx;
589 	bool is_b0 = efx_nic_rev(efx) >= EFX_REV_FALCON_B0;
590 	bool iscsi_digest_en = is_b0;
591 
592 	netif_dbg(efx, hw, efx->net_dev,
593 		  "RX queue %d ring in special buffers %d-%d\n",
594 		  efx_rx_queue_index(rx_queue), rx_queue->rxd.index,
595 		  rx_queue->rxd.index + rx_queue->rxd.entries - 1);
596 
597 	rx_queue->flushed = FLUSH_NONE;
598 
599 	/* Pin RX descriptor ring */
600 	efx_init_special_buffer(efx, &rx_queue->rxd);
601 
602 	/* Push RX descriptor ring to card */
603 	EFX_POPULATE_OWORD_10(rx_desc_ptr,
604 			      FRF_AZ_RX_ISCSI_DDIG_EN, iscsi_digest_en,
605 			      FRF_AZ_RX_ISCSI_HDIG_EN, iscsi_digest_en,
606 			      FRF_AZ_RX_DESCQ_BUF_BASE_ID, rx_queue->rxd.index,
607 			      FRF_AZ_RX_DESCQ_EVQ_ID,
608 			      efx_rx_queue_channel(rx_queue)->channel,
609 			      FRF_AZ_RX_DESCQ_OWNER_ID, 0,
610 			      FRF_AZ_RX_DESCQ_LABEL,
611 			      efx_rx_queue_index(rx_queue),
612 			      FRF_AZ_RX_DESCQ_SIZE,
613 			      __ffs(rx_queue->rxd.entries),
614 			      FRF_AZ_RX_DESCQ_TYPE, 0 /* kernel queue */ ,
615 			      /* For >=B0 this is scatter so disable */
616 			      FRF_AZ_RX_DESCQ_JUMBO, !is_b0,
617 			      FRF_AZ_RX_DESCQ_EN, 1);
618 	efx_writeo_table(efx, &rx_desc_ptr, efx->type->rxd_ptr_tbl_base,
619 			 efx_rx_queue_index(rx_queue));
620 }
621 
efx_flush_rx_queue(struct efx_rx_queue * rx_queue)622 static void efx_flush_rx_queue(struct efx_rx_queue *rx_queue)
623 {
624 	struct efx_nic *efx = rx_queue->efx;
625 	efx_oword_t rx_flush_descq;
626 
627 	rx_queue->flushed = FLUSH_PENDING;
628 
629 	/* Post a flush command */
630 	EFX_POPULATE_OWORD_2(rx_flush_descq,
631 			     FRF_AZ_RX_FLUSH_DESCQ_CMD, 1,
632 			     FRF_AZ_RX_FLUSH_DESCQ,
633 			     efx_rx_queue_index(rx_queue));
634 	efx_writeo(efx, &rx_flush_descq, FR_AZ_RX_FLUSH_DESCQ);
635 }
636 
efx_nic_fini_rx(struct efx_rx_queue * rx_queue)637 void efx_nic_fini_rx(struct efx_rx_queue *rx_queue)
638 {
639 	efx_oword_t rx_desc_ptr;
640 	struct efx_nic *efx = rx_queue->efx;
641 
642 	/* The queue should already have been flushed */
643 	WARN_ON(rx_queue->flushed != FLUSH_DONE);
644 
645 	/* Remove RX descriptor ring from card */
646 	EFX_ZERO_OWORD(rx_desc_ptr);
647 	efx_writeo_table(efx, &rx_desc_ptr, efx->type->rxd_ptr_tbl_base,
648 			 efx_rx_queue_index(rx_queue));
649 
650 	/* Unpin RX descriptor ring */
651 	efx_fini_special_buffer(efx, &rx_queue->rxd);
652 }
653 
654 /* Free buffers backing RX queue */
efx_nic_remove_rx(struct efx_rx_queue * rx_queue)655 void efx_nic_remove_rx(struct efx_rx_queue *rx_queue)
656 {
657 	efx_free_special_buffer(rx_queue->efx, &rx_queue->rxd);
658 }
659 
660 /**************************************************************************
661  *
662  * Event queue processing
663  * Event queues are processed by per-channel tasklets.
664  *
665  **************************************************************************/
666 
667 /* Update a channel's event queue's read pointer (RPTR) register
668  *
669  * This writes the EVQ_RPTR_REG register for the specified channel's
670  * event queue.
671  */
efx_nic_eventq_read_ack(struct efx_channel * channel)672 void efx_nic_eventq_read_ack(struct efx_channel *channel)
673 {
674 	efx_dword_t reg;
675 	struct efx_nic *efx = channel->efx;
676 
677 	EFX_POPULATE_DWORD_1(reg, FRF_AZ_EVQ_RPTR,
678 			     channel->eventq_read_ptr & channel->eventq_mask);
679 	efx_writed_table(efx, &reg, efx->type->evq_rptr_tbl_base,
680 			 channel->channel);
681 }
682 
683 /* Use HW to insert a SW defined event */
efx_generate_event(struct efx_channel * channel,efx_qword_t * event)684 static void efx_generate_event(struct efx_channel *channel, efx_qword_t *event)
685 {
686 	efx_oword_t drv_ev_reg;
687 
688 	BUILD_BUG_ON(FRF_AZ_DRV_EV_DATA_LBN != 0 ||
689 		     FRF_AZ_DRV_EV_DATA_WIDTH != 64);
690 	drv_ev_reg.u32[0] = event->u32[0];
691 	drv_ev_reg.u32[1] = event->u32[1];
692 	drv_ev_reg.u32[2] = 0;
693 	drv_ev_reg.u32[3] = 0;
694 	EFX_SET_OWORD_FIELD(drv_ev_reg, FRF_AZ_DRV_EV_QID, channel->channel);
695 	efx_writeo(channel->efx, &drv_ev_reg, FR_AZ_DRV_EV);
696 }
697 
698 /* Handle a transmit completion event
699  *
700  * The NIC batches TX completion events; the message we receive is of
701  * the form "complete all TX events up to this index".
702  */
703 static int
efx_handle_tx_event(struct efx_channel * channel,efx_qword_t * event)704 efx_handle_tx_event(struct efx_channel *channel, efx_qword_t *event)
705 {
706 	unsigned int tx_ev_desc_ptr;
707 	unsigned int tx_ev_q_label;
708 	struct efx_tx_queue *tx_queue;
709 	struct efx_nic *efx = channel->efx;
710 	int tx_packets = 0;
711 
712 	if (likely(EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_COMP))) {
713 		/* Transmit completion */
714 		tx_ev_desc_ptr = EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_DESC_PTR);
715 		tx_ev_q_label = EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_Q_LABEL);
716 		tx_queue = efx_channel_get_tx_queue(
717 			channel, tx_ev_q_label % EFX_TXQ_TYPES);
718 		tx_packets = ((tx_ev_desc_ptr - tx_queue->read_count) &
719 			      tx_queue->ptr_mask);
720 		channel->irq_mod_score += tx_packets;
721 		efx_xmit_done(tx_queue, tx_ev_desc_ptr);
722 	} else if (EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_WQ_FF_FULL)) {
723 		/* Rewrite the FIFO write pointer */
724 		tx_ev_q_label = EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_Q_LABEL);
725 		tx_queue = efx_channel_get_tx_queue(
726 			channel, tx_ev_q_label % EFX_TXQ_TYPES);
727 
728 		if (efx_dev_registered(efx))
729 			netif_tx_lock(efx->net_dev);
730 		efx_notify_tx_desc(tx_queue);
731 		if (efx_dev_registered(efx))
732 			netif_tx_unlock(efx->net_dev);
733 	} else if (EFX_QWORD_FIELD(*event, FSF_AZ_TX_EV_PKT_ERR) &&
734 		   EFX_WORKAROUND_10727(efx)) {
735 		efx_schedule_reset(efx, RESET_TYPE_TX_DESC_FETCH);
736 	} else {
737 		netif_err(efx, tx_err, efx->net_dev,
738 			  "channel %d unexpected TX event "
739 			  EFX_QWORD_FMT"\n", channel->channel,
740 			  EFX_QWORD_VAL(*event));
741 	}
742 
743 	return tx_packets;
744 }
745 
746 /* Detect errors included in the rx_evt_pkt_ok bit. */
efx_handle_rx_not_ok(struct efx_rx_queue * rx_queue,const efx_qword_t * event,bool * rx_ev_pkt_ok,bool * discard)747 static void efx_handle_rx_not_ok(struct efx_rx_queue *rx_queue,
748 				 const efx_qword_t *event,
749 				 bool *rx_ev_pkt_ok,
750 				 bool *discard)
751 {
752 	struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
753 	struct efx_nic *efx = rx_queue->efx;
754 	bool rx_ev_buf_owner_id_err, rx_ev_ip_hdr_chksum_err;
755 	bool rx_ev_tcp_udp_chksum_err, rx_ev_eth_crc_err;
756 	bool rx_ev_frm_trunc, rx_ev_drib_nib, rx_ev_tobe_disc;
757 	bool rx_ev_other_err, rx_ev_pause_frm;
758 	bool rx_ev_hdr_type, rx_ev_mcast_pkt;
759 	unsigned rx_ev_pkt_type;
760 
761 	rx_ev_hdr_type = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_HDR_TYPE);
762 	rx_ev_mcast_pkt = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_MCAST_PKT);
763 	rx_ev_tobe_disc = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_TOBE_DISC);
764 	rx_ev_pkt_type = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_PKT_TYPE);
765 	rx_ev_buf_owner_id_err = EFX_QWORD_FIELD(*event,
766 						 FSF_AZ_RX_EV_BUF_OWNER_ID_ERR);
767 	rx_ev_ip_hdr_chksum_err = EFX_QWORD_FIELD(*event,
768 						  FSF_AZ_RX_EV_IP_HDR_CHKSUM_ERR);
769 	rx_ev_tcp_udp_chksum_err = EFX_QWORD_FIELD(*event,
770 						   FSF_AZ_RX_EV_TCP_UDP_CHKSUM_ERR);
771 	rx_ev_eth_crc_err = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_ETH_CRC_ERR);
772 	rx_ev_frm_trunc = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_FRM_TRUNC);
773 	rx_ev_drib_nib = ((efx_nic_rev(efx) >= EFX_REV_FALCON_B0) ?
774 			  0 : EFX_QWORD_FIELD(*event, FSF_AA_RX_EV_DRIB_NIB));
775 	rx_ev_pause_frm = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_PAUSE_FRM_ERR);
776 
777 	/* Every error apart from tobe_disc and pause_frm */
778 	rx_ev_other_err = (rx_ev_drib_nib | rx_ev_tcp_udp_chksum_err |
779 			   rx_ev_buf_owner_id_err | rx_ev_eth_crc_err |
780 			   rx_ev_frm_trunc | rx_ev_ip_hdr_chksum_err);
781 
782 	/* Count errors that are not in MAC stats.  Ignore expected
783 	 * checksum errors during self-test. */
784 	if (rx_ev_frm_trunc)
785 		++channel->n_rx_frm_trunc;
786 	else if (rx_ev_tobe_disc)
787 		++channel->n_rx_tobe_disc;
788 	else if (!efx->loopback_selftest) {
789 		if (rx_ev_ip_hdr_chksum_err)
790 			++channel->n_rx_ip_hdr_chksum_err;
791 		else if (rx_ev_tcp_udp_chksum_err)
792 			++channel->n_rx_tcp_udp_chksum_err;
793 	}
794 
795 	/* The frame must be discarded if any of these are true. */
796 	*discard = (rx_ev_eth_crc_err | rx_ev_frm_trunc | rx_ev_drib_nib |
797 		    rx_ev_tobe_disc | rx_ev_pause_frm);
798 
799 	/* TOBE_DISC is expected on unicast mismatches; don't print out an
800 	 * error message.  FRM_TRUNC indicates RXDP dropped the packet due
801 	 * to a FIFO overflow.
802 	 */
803 #ifdef EFX_ENABLE_DEBUG
804 	if (rx_ev_other_err && net_ratelimit()) {
805 		netif_dbg(efx, rx_err, efx->net_dev,
806 			  " RX queue %d unexpected RX event "
807 			  EFX_QWORD_FMT "%s%s%s%s%s%s%s%s\n",
808 			  efx_rx_queue_index(rx_queue), EFX_QWORD_VAL(*event),
809 			  rx_ev_buf_owner_id_err ? " [OWNER_ID_ERR]" : "",
810 			  rx_ev_ip_hdr_chksum_err ?
811 			  " [IP_HDR_CHKSUM_ERR]" : "",
812 			  rx_ev_tcp_udp_chksum_err ?
813 			  " [TCP_UDP_CHKSUM_ERR]" : "",
814 			  rx_ev_eth_crc_err ? " [ETH_CRC_ERR]" : "",
815 			  rx_ev_frm_trunc ? " [FRM_TRUNC]" : "",
816 			  rx_ev_drib_nib ? " [DRIB_NIB]" : "",
817 			  rx_ev_tobe_disc ? " [TOBE_DISC]" : "",
818 			  rx_ev_pause_frm ? " [PAUSE]" : "");
819 	}
820 #endif
821 }
822 
823 /* Handle receive events that are not in-order. */
824 static void
efx_handle_rx_bad_index(struct efx_rx_queue * rx_queue,unsigned index)825 efx_handle_rx_bad_index(struct efx_rx_queue *rx_queue, unsigned index)
826 {
827 	struct efx_nic *efx = rx_queue->efx;
828 	unsigned expected, dropped;
829 
830 	expected = rx_queue->removed_count & rx_queue->ptr_mask;
831 	dropped = (index - expected) & rx_queue->ptr_mask;
832 	netif_info(efx, rx_err, efx->net_dev,
833 		   "dropped %d events (index=%d expected=%d)\n",
834 		   dropped, index, expected);
835 
836 	efx_schedule_reset(efx, EFX_WORKAROUND_5676(efx) ?
837 			   RESET_TYPE_RX_RECOVERY : RESET_TYPE_DISABLE);
838 }
839 
840 /* Handle a packet received event
841  *
842  * The NIC gives a "discard" flag if it's a unicast packet with the
843  * wrong destination address
844  * Also "is multicast" and "matches multicast filter" flags can be used to
845  * discard non-matching multicast packets.
846  */
847 static void
efx_handle_rx_event(struct efx_channel * channel,const efx_qword_t * event)848 efx_handle_rx_event(struct efx_channel *channel, const efx_qword_t *event)
849 {
850 	unsigned int rx_ev_desc_ptr, rx_ev_byte_cnt;
851 	unsigned int rx_ev_hdr_type, rx_ev_mcast_pkt;
852 	unsigned expected_ptr;
853 	bool rx_ev_pkt_ok, discard = false, checksummed;
854 	struct efx_rx_queue *rx_queue;
855 	struct efx_nic *efx = channel->efx;
856 
857 	/* Basic packet information */
858 	rx_ev_byte_cnt = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_BYTE_CNT);
859 	rx_ev_pkt_ok = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_PKT_OK);
860 	rx_ev_hdr_type = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_HDR_TYPE);
861 	WARN_ON(EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_JUMBO_CONT));
862 	WARN_ON(EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_SOP) != 1);
863 	WARN_ON(EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_Q_LABEL) !=
864 		channel->channel);
865 
866 	rx_queue = efx_channel_get_rx_queue(channel);
867 
868 	rx_ev_desc_ptr = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_DESC_PTR);
869 	expected_ptr = rx_queue->removed_count & rx_queue->ptr_mask;
870 	if (unlikely(rx_ev_desc_ptr != expected_ptr))
871 		efx_handle_rx_bad_index(rx_queue, rx_ev_desc_ptr);
872 
873 	if (likely(rx_ev_pkt_ok)) {
874 		/* If packet is marked as OK and packet type is TCP/IP or
875 		 * UDP/IP, then we can rely on the hardware checksum.
876 		 */
877 		checksummed =
878 			likely(efx->rx_checksum_enabled) &&
879 			(rx_ev_hdr_type == FSE_CZ_RX_EV_HDR_TYPE_IPV4V6_TCP ||
880 			 rx_ev_hdr_type == FSE_CZ_RX_EV_HDR_TYPE_IPV4V6_UDP);
881 	} else {
882 		efx_handle_rx_not_ok(rx_queue, event, &rx_ev_pkt_ok, &discard);
883 		checksummed = false;
884 	}
885 
886 	/* Detect multicast packets that didn't match the filter */
887 	rx_ev_mcast_pkt = EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_MCAST_PKT);
888 	if (rx_ev_mcast_pkt) {
889 		unsigned int rx_ev_mcast_hash_match =
890 			EFX_QWORD_FIELD(*event, FSF_AZ_RX_EV_MCAST_HASH_MATCH);
891 
892 		if (unlikely(!rx_ev_mcast_hash_match)) {
893 			++channel->n_rx_mcast_mismatch;
894 			discard = true;
895 		}
896 	}
897 
898 	channel->irq_mod_score += 2;
899 
900 	/* Handle received packet */
901 	efx_rx_packet(rx_queue, rx_ev_desc_ptr, rx_ev_byte_cnt,
902 		      checksummed, discard);
903 }
904 
905 static void
efx_handle_generated_event(struct efx_channel * channel,efx_qword_t * event)906 efx_handle_generated_event(struct efx_channel *channel, efx_qword_t *event)
907 {
908 	struct efx_nic *efx = channel->efx;
909 	unsigned code;
910 
911 	code = EFX_QWORD_FIELD(*event, FSF_AZ_DRV_GEN_EV_MAGIC);
912 	if (code == EFX_CHANNEL_MAGIC_TEST(channel))
913 		; /* ignore */
914 	else if (code == EFX_CHANNEL_MAGIC_FILL(channel))
915 		/* The queue must be empty, so we won't receive any rx
916 		 * events, so efx_process_channel() won't refill the
917 		 * queue. Refill it here */
918 		efx_fast_push_rx_descriptors(efx_channel_get_rx_queue(channel));
919 	else
920 		netif_dbg(efx, hw, efx->net_dev, "channel %d received "
921 			  "generated event "EFX_QWORD_FMT"\n",
922 			  channel->channel, EFX_QWORD_VAL(*event));
923 }
924 
925 static void
efx_handle_driver_event(struct efx_channel * channel,efx_qword_t * event)926 efx_handle_driver_event(struct efx_channel *channel, efx_qword_t *event)
927 {
928 	struct efx_nic *efx = channel->efx;
929 	unsigned int ev_sub_code;
930 	unsigned int ev_sub_data;
931 
932 	ev_sub_code = EFX_QWORD_FIELD(*event, FSF_AZ_DRIVER_EV_SUBCODE);
933 	ev_sub_data = EFX_QWORD_FIELD(*event, FSF_AZ_DRIVER_EV_SUBDATA);
934 
935 	switch (ev_sub_code) {
936 	case FSE_AZ_TX_DESCQ_FLS_DONE_EV:
937 		netif_vdbg(efx, hw, efx->net_dev, "channel %d TXQ %d flushed\n",
938 			   channel->channel, ev_sub_data);
939 		break;
940 	case FSE_AZ_RX_DESCQ_FLS_DONE_EV:
941 		netif_vdbg(efx, hw, efx->net_dev, "channel %d RXQ %d flushed\n",
942 			   channel->channel, ev_sub_data);
943 		break;
944 	case FSE_AZ_EVQ_INIT_DONE_EV:
945 		netif_dbg(efx, hw, efx->net_dev,
946 			  "channel %d EVQ %d initialised\n",
947 			  channel->channel, ev_sub_data);
948 		break;
949 	case FSE_AZ_SRM_UPD_DONE_EV:
950 		netif_vdbg(efx, hw, efx->net_dev,
951 			   "channel %d SRAM update done\n", channel->channel);
952 		break;
953 	case FSE_AZ_WAKE_UP_EV:
954 		netif_vdbg(efx, hw, efx->net_dev,
955 			   "channel %d RXQ %d wakeup event\n",
956 			   channel->channel, ev_sub_data);
957 		break;
958 	case FSE_AZ_TIMER_EV:
959 		netif_vdbg(efx, hw, efx->net_dev,
960 			   "channel %d RX queue %d timer expired\n",
961 			   channel->channel, ev_sub_data);
962 		break;
963 	case FSE_AA_RX_RECOVER_EV:
964 		netif_err(efx, rx_err, efx->net_dev,
965 			  "channel %d seen DRIVER RX_RESET event. "
966 			"Resetting.\n", channel->channel);
967 		atomic_inc(&efx->rx_reset);
968 		efx_schedule_reset(efx,
969 				   EFX_WORKAROUND_6555(efx) ?
970 				   RESET_TYPE_RX_RECOVERY :
971 				   RESET_TYPE_DISABLE);
972 		break;
973 	case FSE_BZ_RX_DSC_ERROR_EV:
974 		netif_err(efx, rx_err, efx->net_dev,
975 			  "RX DMA Q %d reports descriptor fetch error."
976 			  " RX Q %d is disabled.\n", ev_sub_data, ev_sub_data);
977 		efx_schedule_reset(efx, RESET_TYPE_RX_DESC_FETCH);
978 		break;
979 	case FSE_BZ_TX_DSC_ERROR_EV:
980 		netif_err(efx, tx_err, efx->net_dev,
981 			  "TX DMA Q %d reports descriptor fetch error."
982 			  " TX Q %d is disabled.\n", ev_sub_data, ev_sub_data);
983 		efx_schedule_reset(efx, RESET_TYPE_TX_DESC_FETCH);
984 		break;
985 	default:
986 		netif_vdbg(efx, hw, efx->net_dev,
987 			   "channel %d unknown driver event code %d "
988 			   "data %04x\n", channel->channel, ev_sub_code,
989 			   ev_sub_data);
990 		break;
991 	}
992 }
993 
efx_nic_process_eventq(struct efx_channel * channel,int budget)994 int efx_nic_process_eventq(struct efx_channel *channel, int budget)
995 {
996 	struct efx_nic *efx = channel->efx;
997 	unsigned int read_ptr;
998 	efx_qword_t event, *p_event;
999 	int ev_code;
1000 	int tx_packets = 0;
1001 	int spent = 0;
1002 
1003 	read_ptr = channel->eventq_read_ptr;
1004 
1005 	for (;;) {
1006 		p_event = efx_event(channel, read_ptr);
1007 		event = *p_event;
1008 
1009 		if (!efx_event_present(&event))
1010 			/* End of events */
1011 			break;
1012 
1013 		netif_vdbg(channel->efx, intr, channel->efx->net_dev,
1014 			   "channel %d event is "EFX_QWORD_FMT"\n",
1015 			   channel->channel, EFX_QWORD_VAL(event));
1016 
1017 		/* Clear this event by marking it all ones */
1018 		EFX_SET_QWORD(*p_event);
1019 
1020 		++read_ptr;
1021 
1022 		ev_code = EFX_QWORD_FIELD(event, FSF_AZ_EV_CODE);
1023 
1024 		switch (ev_code) {
1025 		case FSE_AZ_EV_CODE_RX_EV:
1026 			efx_handle_rx_event(channel, &event);
1027 			if (++spent == budget)
1028 				goto out;
1029 			break;
1030 		case FSE_AZ_EV_CODE_TX_EV:
1031 			tx_packets += efx_handle_tx_event(channel, &event);
1032 			if (tx_packets > efx->txq_entries) {
1033 				spent = budget;
1034 				goto out;
1035 			}
1036 			break;
1037 		case FSE_AZ_EV_CODE_DRV_GEN_EV:
1038 			efx_handle_generated_event(channel, &event);
1039 			break;
1040 		case FSE_AZ_EV_CODE_DRIVER_EV:
1041 			efx_handle_driver_event(channel, &event);
1042 			break;
1043 		case FSE_CZ_EV_CODE_MCDI_EV:
1044 			efx_mcdi_process_event(channel, &event);
1045 			break;
1046 		case FSE_AZ_EV_CODE_GLOBAL_EV:
1047 			if (efx->type->handle_global_event &&
1048 			    efx->type->handle_global_event(channel, &event))
1049 				break;
1050 			/* else fall through */
1051 		default:
1052 			netif_err(channel->efx, hw, channel->efx->net_dev,
1053 				  "channel %d unknown event type %d (data "
1054 				  EFX_QWORD_FMT ")\n", channel->channel,
1055 				  ev_code, EFX_QWORD_VAL(event));
1056 		}
1057 	}
1058 
1059 out:
1060 	channel->eventq_read_ptr = read_ptr;
1061 	return spent;
1062 }
1063 
1064 /* Check whether an event is present in the eventq at the current
1065  * read pointer.  Only useful for self-test.
1066  */
efx_nic_event_present(struct efx_channel * channel)1067 bool efx_nic_event_present(struct efx_channel *channel)
1068 {
1069 	return efx_event_present(efx_event(channel, channel->eventq_read_ptr));
1070 }
1071 
1072 /* Allocate buffer table entries for event queue */
efx_nic_probe_eventq(struct efx_channel * channel)1073 int efx_nic_probe_eventq(struct efx_channel *channel)
1074 {
1075 	struct efx_nic *efx = channel->efx;
1076 	unsigned entries;
1077 
1078 	entries = channel->eventq_mask + 1;
1079 	return efx_alloc_special_buffer(efx, &channel->eventq,
1080 					entries * sizeof(efx_qword_t));
1081 }
1082 
efx_nic_init_eventq(struct efx_channel * channel)1083 void efx_nic_init_eventq(struct efx_channel *channel)
1084 {
1085 	efx_oword_t reg;
1086 	struct efx_nic *efx = channel->efx;
1087 
1088 	netif_dbg(efx, hw, efx->net_dev,
1089 		  "channel %d event queue in special buffers %d-%d\n",
1090 		  channel->channel, channel->eventq.index,
1091 		  channel->eventq.index + channel->eventq.entries - 1);
1092 
1093 	if (efx_nic_rev(efx) >= EFX_REV_SIENA_A0) {
1094 		EFX_POPULATE_OWORD_3(reg,
1095 				     FRF_CZ_TIMER_Q_EN, 1,
1096 				     FRF_CZ_HOST_NOTIFY_MODE, 0,
1097 				     FRF_CZ_TIMER_MODE, FFE_CZ_TIMER_MODE_DIS);
1098 		efx_writeo_table(efx, &reg, FR_BZ_TIMER_TBL, channel->channel);
1099 	}
1100 
1101 	/* Pin event queue buffer */
1102 	efx_init_special_buffer(efx, &channel->eventq);
1103 
1104 	/* Fill event queue with all ones (i.e. empty events) */
1105 	memset(channel->eventq.addr, 0xff, channel->eventq.len);
1106 
1107 	/* Push event queue to card */
1108 	EFX_POPULATE_OWORD_3(reg,
1109 			     FRF_AZ_EVQ_EN, 1,
1110 			     FRF_AZ_EVQ_SIZE, __ffs(channel->eventq.entries),
1111 			     FRF_AZ_EVQ_BUF_BASE_ID, channel->eventq.index);
1112 	efx_writeo_table(efx, &reg, efx->type->evq_ptr_tbl_base,
1113 			 channel->channel);
1114 
1115 	efx->type->push_irq_moderation(channel);
1116 }
1117 
efx_nic_fini_eventq(struct efx_channel * channel)1118 void efx_nic_fini_eventq(struct efx_channel *channel)
1119 {
1120 	efx_oword_t reg;
1121 	struct efx_nic *efx = channel->efx;
1122 
1123 	/* Remove event queue from card */
1124 	EFX_ZERO_OWORD(reg);
1125 	efx_writeo_table(efx, &reg, efx->type->evq_ptr_tbl_base,
1126 			 channel->channel);
1127 	if (efx_nic_rev(efx) >= EFX_REV_SIENA_A0)
1128 		efx_writeo_table(efx, &reg, FR_BZ_TIMER_TBL, channel->channel);
1129 
1130 	/* Unpin event queue */
1131 	efx_fini_special_buffer(efx, &channel->eventq);
1132 }
1133 
1134 /* Free buffers backing event queue */
efx_nic_remove_eventq(struct efx_channel * channel)1135 void efx_nic_remove_eventq(struct efx_channel *channel)
1136 {
1137 	efx_free_special_buffer(channel->efx, &channel->eventq);
1138 }
1139 
1140 
efx_nic_generate_test_event(struct efx_channel * channel)1141 void efx_nic_generate_test_event(struct efx_channel *channel)
1142 {
1143 	unsigned int magic = EFX_CHANNEL_MAGIC_TEST(channel);
1144 	efx_qword_t test_event;
1145 
1146 	EFX_POPULATE_QWORD_2(test_event, FSF_AZ_EV_CODE,
1147 			     FSE_AZ_EV_CODE_DRV_GEN_EV,
1148 			     FSF_AZ_DRV_GEN_EV_MAGIC, magic);
1149 	efx_generate_event(channel, &test_event);
1150 }
1151 
efx_nic_generate_fill_event(struct efx_channel * channel)1152 void efx_nic_generate_fill_event(struct efx_channel *channel)
1153 {
1154 	unsigned int magic = EFX_CHANNEL_MAGIC_FILL(channel);
1155 	efx_qword_t test_event;
1156 
1157 	EFX_POPULATE_QWORD_2(test_event, FSF_AZ_EV_CODE,
1158 			     FSE_AZ_EV_CODE_DRV_GEN_EV,
1159 			     FSF_AZ_DRV_GEN_EV_MAGIC, magic);
1160 	efx_generate_event(channel, &test_event);
1161 }
1162 
1163 /**************************************************************************
1164  *
1165  * Flush handling
1166  *
1167  **************************************************************************/
1168 
1169 
efx_poll_flush_events(struct efx_nic * efx)1170 static void efx_poll_flush_events(struct efx_nic *efx)
1171 {
1172 	struct efx_channel *channel = efx_get_channel(efx, 0);
1173 	struct efx_tx_queue *tx_queue;
1174 	struct efx_rx_queue *rx_queue;
1175 	unsigned int read_ptr = channel->eventq_read_ptr;
1176 	unsigned int end_ptr = read_ptr + channel->eventq_mask - 1;
1177 
1178 	do {
1179 		efx_qword_t *event = efx_event(channel, read_ptr);
1180 		int ev_code, ev_sub_code, ev_queue;
1181 		bool ev_failed;
1182 
1183 		if (!efx_event_present(event))
1184 			break;
1185 
1186 		ev_code = EFX_QWORD_FIELD(*event, FSF_AZ_EV_CODE);
1187 		ev_sub_code = EFX_QWORD_FIELD(*event,
1188 					      FSF_AZ_DRIVER_EV_SUBCODE);
1189 		if (ev_code == FSE_AZ_EV_CODE_DRIVER_EV &&
1190 		    ev_sub_code == FSE_AZ_TX_DESCQ_FLS_DONE_EV) {
1191 			ev_queue = EFX_QWORD_FIELD(*event,
1192 						   FSF_AZ_DRIVER_EV_SUBDATA);
1193 			if (ev_queue < EFX_TXQ_TYPES * efx->n_tx_channels) {
1194 				tx_queue = efx_get_tx_queue(
1195 					efx, ev_queue / EFX_TXQ_TYPES,
1196 					ev_queue % EFX_TXQ_TYPES);
1197 				tx_queue->flushed = FLUSH_DONE;
1198 			}
1199 		} else if (ev_code == FSE_AZ_EV_CODE_DRIVER_EV &&
1200 			   ev_sub_code == FSE_AZ_RX_DESCQ_FLS_DONE_EV) {
1201 			ev_queue = EFX_QWORD_FIELD(
1202 				*event, FSF_AZ_DRIVER_EV_RX_DESCQ_ID);
1203 			ev_failed = EFX_QWORD_FIELD(
1204 				*event, FSF_AZ_DRIVER_EV_RX_FLUSH_FAIL);
1205 			if (ev_queue < efx->n_rx_channels) {
1206 				rx_queue = efx_get_rx_queue(efx, ev_queue);
1207 				rx_queue->flushed =
1208 					ev_failed ? FLUSH_FAILED : FLUSH_DONE;
1209 			}
1210 		}
1211 
1212 		/* We're about to destroy the queue anyway, so
1213 		 * it's ok to throw away every non-flush event */
1214 		EFX_SET_QWORD(*event);
1215 
1216 		++read_ptr;
1217 	} while (read_ptr != end_ptr);
1218 
1219 	channel->eventq_read_ptr = read_ptr;
1220 }
1221 
1222 /* Handle tx and rx flushes at the same time, since they run in
1223  * parallel in the hardware and there's no reason for us to
1224  * serialise them */
efx_nic_flush_queues(struct efx_nic * efx)1225 int efx_nic_flush_queues(struct efx_nic *efx)
1226 {
1227 	struct efx_channel *channel;
1228 	struct efx_rx_queue *rx_queue;
1229 	struct efx_tx_queue *tx_queue;
1230 	int i, tx_pending, rx_pending;
1231 
1232 	/* If necessary prepare the hardware for flushing */
1233 	efx->type->prepare_flush(efx);
1234 
1235 	/* Flush all tx queues in parallel */
1236 	efx_for_each_channel(channel, efx) {
1237 		efx_for_each_possible_channel_tx_queue(tx_queue, channel) {
1238 			if (tx_queue->initialised)
1239 				efx_flush_tx_queue(tx_queue);
1240 		}
1241 	}
1242 
1243 	/* The hardware supports four concurrent rx flushes, each of which may
1244 	 * need to be retried if there is an outstanding descriptor fetch */
1245 	for (i = 0; i < EFX_FLUSH_POLL_COUNT; ++i) {
1246 		rx_pending = tx_pending = 0;
1247 		efx_for_each_channel(channel, efx) {
1248 			efx_for_each_channel_rx_queue(rx_queue, channel) {
1249 				if (rx_queue->flushed == FLUSH_PENDING)
1250 					++rx_pending;
1251 			}
1252 		}
1253 		efx_for_each_channel(channel, efx) {
1254 			efx_for_each_channel_rx_queue(rx_queue, channel) {
1255 				if (rx_pending == EFX_RX_FLUSH_COUNT)
1256 					break;
1257 				if (rx_queue->flushed == FLUSH_FAILED ||
1258 				    rx_queue->flushed == FLUSH_NONE) {
1259 					efx_flush_rx_queue(rx_queue);
1260 					++rx_pending;
1261 				}
1262 			}
1263 			efx_for_each_possible_channel_tx_queue(tx_queue, channel) {
1264 				if (tx_queue->initialised &&
1265 				    tx_queue->flushed != FLUSH_DONE)
1266 					++tx_pending;
1267 			}
1268 		}
1269 
1270 		if (rx_pending == 0 && tx_pending == 0)
1271 			return 0;
1272 
1273 		msleep(EFX_FLUSH_INTERVAL);
1274 		efx_poll_flush_events(efx);
1275 	}
1276 
1277 	/* Mark the queues as all flushed. We're going to return failure
1278 	 * leading to a reset, or fake up success anyway */
1279 	efx_for_each_channel(channel, efx) {
1280 		efx_for_each_possible_channel_tx_queue(tx_queue, channel) {
1281 			if (tx_queue->initialised &&
1282 			    tx_queue->flushed != FLUSH_DONE)
1283 				netif_err(efx, hw, efx->net_dev,
1284 					  "tx queue %d flush command timed out\n",
1285 					  tx_queue->queue);
1286 			tx_queue->flushed = FLUSH_DONE;
1287 		}
1288 		efx_for_each_channel_rx_queue(rx_queue, channel) {
1289 			if (rx_queue->flushed != FLUSH_DONE)
1290 				netif_err(efx, hw, efx->net_dev,
1291 					  "rx queue %d flush command timed out\n",
1292 					  efx_rx_queue_index(rx_queue));
1293 			rx_queue->flushed = FLUSH_DONE;
1294 		}
1295 	}
1296 
1297 	return -ETIMEDOUT;
1298 }
1299 
1300 /**************************************************************************
1301  *
1302  * Hardware interrupts
1303  * The hardware interrupt handler does very little work; all the event
1304  * queue processing is carried out by per-channel tasklets.
1305  *
1306  **************************************************************************/
1307 
1308 /* Enable/disable/generate interrupts */
efx_nic_interrupts(struct efx_nic * efx,bool enabled,bool force)1309 static inline void efx_nic_interrupts(struct efx_nic *efx,
1310 				      bool enabled, bool force)
1311 {
1312 	efx_oword_t int_en_reg_ker;
1313 
1314 	EFX_POPULATE_OWORD_3(int_en_reg_ker,
1315 			     FRF_AZ_KER_INT_LEVE_SEL, efx->fatal_irq_level,
1316 			     FRF_AZ_KER_INT_KER, force,
1317 			     FRF_AZ_DRV_INT_EN_KER, enabled);
1318 	efx_writeo(efx, &int_en_reg_ker, FR_AZ_INT_EN_KER);
1319 }
1320 
efx_nic_enable_interrupts(struct efx_nic * efx)1321 void efx_nic_enable_interrupts(struct efx_nic *efx)
1322 {
1323 	struct efx_channel *channel;
1324 
1325 	EFX_ZERO_OWORD(*((efx_oword_t *) efx->irq_status.addr));
1326 	wmb(); /* Ensure interrupt vector is clear before interrupts enabled */
1327 
1328 	/* Enable interrupts */
1329 	efx_nic_interrupts(efx, true, false);
1330 
1331 	/* Force processing of all the channels to get the EVQ RPTRs up to
1332 	   date */
1333 	efx_for_each_channel(channel, efx)
1334 		efx_schedule_channel(channel);
1335 }
1336 
efx_nic_disable_interrupts(struct efx_nic * efx)1337 void efx_nic_disable_interrupts(struct efx_nic *efx)
1338 {
1339 	/* Disable interrupts */
1340 	efx_nic_interrupts(efx, false, false);
1341 }
1342 
1343 /* Generate a test interrupt
1344  * Interrupt must already have been enabled, otherwise nasty things
1345  * may happen.
1346  */
efx_nic_generate_interrupt(struct efx_nic * efx)1347 void efx_nic_generate_interrupt(struct efx_nic *efx)
1348 {
1349 	efx_nic_interrupts(efx, true, true);
1350 }
1351 
1352 /* Process a fatal interrupt
1353  * Disable bus mastering ASAP and schedule a reset
1354  */
efx_nic_fatal_interrupt(struct efx_nic * efx)1355 irqreturn_t efx_nic_fatal_interrupt(struct efx_nic *efx)
1356 {
1357 	struct falcon_nic_data *nic_data = efx->nic_data;
1358 	efx_oword_t *int_ker = efx->irq_status.addr;
1359 	efx_oword_t fatal_intr;
1360 	int error, mem_perr;
1361 
1362 	efx_reado(efx, &fatal_intr, FR_AZ_FATAL_INTR_KER);
1363 	error = EFX_OWORD_FIELD(fatal_intr, FRF_AZ_FATAL_INTR);
1364 
1365 	netif_err(efx, hw, efx->net_dev, "SYSTEM ERROR "EFX_OWORD_FMT" status "
1366 		  EFX_OWORD_FMT ": %s\n", EFX_OWORD_VAL(*int_ker),
1367 		  EFX_OWORD_VAL(fatal_intr),
1368 		  error ? "disabling bus mastering" : "no recognised error");
1369 
1370 	/* If this is a memory parity error dump which blocks are offending */
1371 	mem_perr = (EFX_OWORD_FIELD(fatal_intr, FRF_AZ_MEM_PERR_INT_KER) ||
1372 		    EFX_OWORD_FIELD(fatal_intr, FRF_AZ_SRM_PERR_INT_KER));
1373 	if (mem_perr) {
1374 		efx_oword_t reg;
1375 		efx_reado(efx, &reg, FR_AZ_MEM_STAT);
1376 		netif_err(efx, hw, efx->net_dev,
1377 			  "SYSTEM ERROR: memory parity error "EFX_OWORD_FMT"\n",
1378 			  EFX_OWORD_VAL(reg));
1379 	}
1380 
1381 	/* Disable both devices */
1382 	pci_clear_master(efx->pci_dev);
1383 	if (efx_nic_is_dual_func(efx))
1384 		pci_clear_master(nic_data->pci_dev2);
1385 	efx_nic_disable_interrupts(efx);
1386 
1387 	/* Count errors and reset or disable the NIC accordingly */
1388 	if (efx->int_error_count == 0 ||
1389 	    time_after(jiffies, efx->int_error_expire)) {
1390 		efx->int_error_count = 0;
1391 		efx->int_error_expire =
1392 			jiffies + EFX_INT_ERROR_EXPIRE * HZ;
1393 	}
1394 	if (++efx->int_error_count < EFX_MAX_INT_ERRORS) {
1395 		netif_err(efx, hw, efx->net_dev,
1396 			  "SYSTEM ERROR - reset scheduled\n");
1397 		efx_schedule_reset(efx, RESET_TYPE_INT_ERROR);
1398 	} else {
1399 		netif_err(efx, hw, efx->net_dev,
1400 			  "SYSTEM ERROR - max number of errors seen."
1401 			  "NIC will be disabled\n");
1402 		efx_schedule_reset(efx, RESET_TYPE_DISABLE);
1403 	}
1404 
1405 	return IRQ_HANDLED;
1406 }
1407 
1408 /* Handle a legacy interrupt
1409  * Acknowledges the interrupt and schedule event queue processing.
1410  */
efx_legacy_interrupt(int irq,void * dev_id)1411 static irqreturn_t efx_legacy_interrupt(int irq, void *dev_id)
1412 {
1413 	struct efx_nic *efx = dev_id;
1414 	efx_oword_t *int_ker = efx->irq_status.addr;
1415 	irqreturn_t result = IRQ_NONE;
1416 	struct efx_channel *channel;
1417 	efx_dword_t reg;
1418 	u32 queues;
1419 	int syserr;
1420 
1421 	/* Could this be ours?  If interrupts are disabled then the
1422 	 * channel state may not be valid.
1423 	 */
1424 	if (!efx->legacy_irq_enabled)
1425 		return result;
1426 
1427 	/* Read the ISR which also ACKs the interrupts */
1428 	efx_readd(efx, &reg, FR_BZ_INT_ISR0);
1429 	queues = EFX_EXTRACT_DWORD(reg, 0, 31);
1430 
1431 	/* Check to see if we have a serious error condition */
1432 	if (queues & (1U << efx->fatal_irq_level)) {
1433 		syserr = EFX_OWORD_FIELD(*int_ker, FSF_AZ_NET_IVEC_FATAL_INT);
1434 		if (unlikely(syserr))
1435 			return efx_nic_fatal_interrupt(efx);
1436 	}
1437 
1438 	if (queues != 0) {
1439 		if (EFX_WORKAROUND_15783(efx))
1440 			efx->irq_zero_count = 0;
1441 
1442 		/* Schedule processing of any interrupting queues */
1443 		efx_for_each_channel(channel, efx) {
1444 			if (queues & 1)
1445 				efx_schedule_channel(channel);
1446 			queues >>= 1;
1447 		}
1448 		result = IRQ_HANDLED;
1449 
1450 	} else if (EFX_WORKAROUND_15783(efx)) {
1451 		efx_qword_t *event;
1452 
1453 		/* We can't return IRQ_HANDLED more than once on seeing ISR=0
1454 		 * because this might be a shared interrupt. */
1455 		if (efx->irq_zero_count++ == 0)
1456 			result = IRQ_HANDLED;
1457 
1458 		/* Ensure we schedule or rearm all event queues */
1459 		efx_for_each_channel(channel, efx) {
1460 			event = efx_event(channel, channel->eventq_read_ptr);
1461 			if (efx_event_present(event))
1462 				efx_schedule_channel(channel);
1463 			else
1464 				efx_nic_eventq_read_ack(channel);
1465 		}
1466 	}
1467 
1468 	if (result == IRQ_HANDLED) {
1469 		efx->last_irq_cpu = raw_smp_processor_id();
1470 		netif_vdbg(efx, intr, efx->net_dev,
1471 			   "IRQ %d on CPU %d status " EFX_DWORD_FMT "\n",
1472 			   irq, raw_smp_processor_id(), EFX_DWORD_VAL(reg));
1473 	}
1474 
1475 	return result;
1476 }
1477 
1478 /* Handle an MSI interrupt
1479  *
1480  * Handle an MSI hardware interrupt.  This routine schedules event
1481  * queue processing.  No interrupt acknowledgement cycle is necessary.
1482  * Also, we never need to check that the interrupt is for us, since
1483  * MSI interrupts cannot be shared.
1484  */
efx_msi_interrupt(int irq,void * dev_id)1485 static irqreturn_t efx_msi_interrupt(int irq, void *dev_id)
1486 {
1487 	struct efx_channel *channel = *(struct efx_channel **)dev_id;
1488 	struct efx_nic *efx = channel->efx;
1489 	efx_oword_t *int_ker = efx->irq_status.addr;
1490 	int syserr;
1491 
1492 	efx->last_irq_cpu = raw_smp_processor_id();
1493 	netif_vdbg(efx, intr, efx->net_dev,
1494 		   "IRQ %d on CPU %d status " EFX_OWORD_FMT "\n",
1495 		   irq, raw_smp_processor_id(), EFX_OWORD_VAL(*int_ker));
1496 
1497 	/* Check to see if we have a serious error condition */
1498 	if (channel->channel == efx->fatal_irq_level) {
1499 		syserr = EFX_OWORD_FIELD(*int_ker, FSF_AZ_NET_IVEC_FATAL_INT);
1500 		if (unlikely(syserr))
1501 			return efx_nic_fatal_interrupt(efx);
1502 	}
1503 
1504 	/* Schedule processing of the channel */
1505 	efx_schedule_channel(channel);
1506 
1507 	return IRQ_HANDLED;
1508 }
1509 
1510 
1511 /* Setup RSS indirection table.
1512  * This maps from the hash value of the packet to RXQ
1513  */
efx_nic_push_rx_indir_table(struct efx_nic * efx)1514 void efx_nic_push_rx_indir_table(struct efx_nic *efx)
1515 {
1516 	size_t i = 0;
1517 	efx_dword_t dword;
1518 
1519 	if (efx_nic_rev(efx) < EFX_REV_FALCON_B0)
1520 		return;
1521 
1522 	BUILD_BUG_ON(ARRAY_SIZE(efx->rx_indir_table) !=
1523 		     FR_BZ_RX_INDIRECTION_TBL_ROWS);
1524 
1525 	for (i = 0; i < FR_BZ_RX_INDIRECTION_TBL_ROWS; i++) {
1526 		EFX_POPULATE_DWORD_1(dword, FRF_BZ_IT_QUEUE,
1527 				     efx->rx_indir_table[i]);
1528 		efx_writed_table(efx, &dword, FR_BZ_RX_INDIRECTION_TBL, i);
1529 	}
1530 }
1531 
1532 /* Hook interrupt handler(s)
1533  * Try MSI and then legacy interrupts.
1534  */
efx_nic_init_interrupt(struct efx_nic * efx)1535 int efx_nic_init_interrupt(struct efx_nic *efx)
1536 {
1537 	struct efx_channel *channel;
1538 	int rc;
1539 
1540 	if (!EFX_INT_MODE_USE_MSI(efx)) {
1541 		irq_handler_t handler;
1542 		if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0)
1543 			handler = efx_legacy_interrupt;
1544 		else
1545 			handler = falcon_legacy_interrupt_a1;
1546 
1547 		rc = request_irq(efx->legacy_irq, handler, IRQF_SHARED,
1548 				 efx->name, efx);
1549 		if (rc) {
1550 			netif_err(efx, drv, efx->net_dev,
1551 				  "failed to hook legacy IRQ %d\n",
1552 				  efx->pci_dev->irq);
1553 			goto fail1;
1554 		}
1555 		return 0;
1556 	}
1557 
1558 	/* Hook MSI or MSI-X interrupt */
1559 	efx_for_each_channel(channel, efx) {
1560 		rc = request_irq(channel->irq, efx_msi_interrupt,
1561 				 IRQF_PROBE_SHARED, /* Not shared */
1562 				 efx->channel_name[channel->channel],
1563 				 &efx->channel[channel->channel]);
1564 		if (rc) {
1565 			netif_err(efx, drv, efx->net_dev,
1566 				  "failed to hook IRQ %d\n", channel->irq);
1567 			goto fail2;
1568 		}
1569 	}
1570 
1571 	return 0;
1572 
1573  fail2:
1574 	efx_for_each_channel(channel, efx)
1575 		free_irq(channel->irq, &efx->channel[channel->channel]);
1576  fail1:
1577 	return rc;
1578 }
1579 
efx_nic_fini_interrupt(struct efx_nic * efx)1580 void efx_nic_fini_interrupt(struct efx_nic *efx)
1581 {
1582 	struct efx_channel *channel;
1583 	efx_oword_t reg;
1584 
1585 	/* Disable MSI/MSI-X interrupts */
1586 	efx_for_each_channel(channel, efx) {
1587 		if (channel->irq)
1588 			free_irq(channel->irq, &efx->channel[channel->channel]);
1589 	}
1590 
1591 	/* ACK legacy interrupt */
1592 	if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0)
1593 		efx_reado(efx, &reg, FR_BZ_INT_ISR0);
1594 	else
1595 		falcon_irq_ack_a1(efx);
1596 
1597 	/* Disable legacy interrupt */
1598 	if (efx->legacy_irq)
1599 		free_irq(efx->legacy_irq, efx);
1600 }
1601 
efx_nic_fpga_ver(struct efx_nic * efx)1602 u32 efx_nic_fpga_ver(struct efx_nic *efx)
1603 {
1604 	efx_oword_t altera_build;
1605 	efx_reado(efx, &altera_build, FR_AZ_ALTERA_BUILD);
1606 	return EFX_OWORD_FIELD(altera_build, FRF_AZ_ALTERA_BUILD_VER);
1607 }
1608 
efx_nic_init_common(struct efx_nic * efx)1609 void efx_nic_init_common(struct efx_nic *efx)
1610 {
1611 	efx_oword_t temp;
1612 
1613 	/* Set positions of descriptor caches in SRAM. */
1614 	EFX_POPULATE_OWORD_1(temp, FRF_AZ_SRM_TX_DC_BASE_ADR,
1615 			     efx->type->tx_dc_base / 8);
1616 	efx_writeo(efx, &temp, FR_AZ_SRM_TX_DC_CFG);
1617 	EFX_POPULATE_OWORD_1(temp, FRF_AZ_SRM_RX_DC_BASE_ADR,
1618 			     efx->type->rx_dc_base / 8);
1619 	efx_writeo(efx, &temp, FR_AZ_SRM_RX_DC_CFG);
1620 
1621 	/* Set TX descriptor cache size. */
1622 	BUILD_BUG_ON(TX_DC_ENTRIES != (8 << TX_DC_ENTRIES_ORDER));
1623 	EFX_POPULATE_OWORD_1(temp, FRF_AZ_TX_DC_SIZE, TX_DC_ENTRIES_ORDER);
1624 	efx_writeo(efx, &temp, FR_AZ_TX_DC_CFG);
1625 
1626 	/* Set RX descriptor cache size.  Set low watermark to size-8, as
1627 	 * this allows most efficient prefetching.
1628 	 */
1629 	BUILD_BUG_ON(RX_DC_ENTRIES != (8 << RX_DC_ENTRIES_ORDER));
1630 	EFX_POPULATE_OWORD_1(temp, FRF_AZ_RX_DC_SIZE, RX_DC_ENTRIES_ORDER);
1631 	efx_writeo(efx, &temp, FR_AZ_RX_DC_CFG);
1632 	EFX_POPULATE_OWORD_1(temp, FRF_AZ_RX_DC_PF_LWM, RX_DC_ENTRIES - 8);
1633 	efx_writeo(efx, &temp, FR_AZ_RX_DC_PF_WM);
1634 
1635 	/* Program INT_KER address */
1636 	EFX_POPULATE_OWORD_2(temp,
1637 			     FRF_AZ_NORM_INT_VEC_DIS_KER,
1638 			     EFX_INT_MODE_USE_MSI(efx),
1639 			     FRF_AZ_INT_ADR_KER, efx->irq_status.dma_addr);
1640 	efx_writeo(efx, &temp, FR_AZ_INT_ADR_KER);
1641 
1642 	if (EFX_WORKAROUND_17213(efx) && !EFX_INT_MODE_USE_MSI(efx))
1643 		/* Use an interrupt level unused by event queues */
1644 		efx->fatal_irq_level = 0x1f;
1645 	else
1646 		/* Use a valid MSI-X vector */
1647 		efx->fatal_irq_level = 0;
1648 
1649 	/* Enable all the genuinely fatal interrupts.  (They are still
1650 	 * masked by the overall interrupt mask, controlled by
1651 	 * falcon_interrupts()).
1652 	 *
1653 	 * Note: All other fatal interrupts are enabled
1654 	 */
1655 	EFX_POPULATE_OWORD_3(temp,
1656 			     FRF_AZ_ILL_ADR_INT_KER_EN, 1,
1657 			     FRF_AZ_RBUF_OWN_INT_KER_EN, 1,
1658 			     FRF_AZ_TBUF_OWN_INT_KER_EN, 1);
1659 	if (efx_nic_rev(efx) >= EFX_REV_SIENA_A0)
1660 		EFX_SET_OWORD_FIELD(temp, FRF_CZ_SRAM_PERR_INT_P_KER_EN, 1);
1661 	EFX_INVERT_OWORD(temp);
1662 	efx_writeo(efx, &temp, FR_AZ_FATAL_INTR_KER);
1663 
1664 	efx_nic_push_rx_indir_table(efx);
1665 
1666 	/* Disable the ugly timer-based TX DMA backoff and allow TX DMA to be
1667 	 * controlled by the RX FIFO fill level. Set arbitration to one pkt/Q.
1668 	 */
1669 	efx_reado(efx, &temp, FR_AZ_TX_RESERVED);
1670 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_RX_SPACER, 0xfe);
1671 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_RX_SPACER_EN, 1);
1672 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_ONE_PKT_PER_Q, 1);
1673 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_PUSH_EN, 1);
1674 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_DIS_NON_IP_EV, 1);
1675 	/* Enable SW_EV to inherit in char driver - assume harmless here */
1676 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_SOFT_EVT_EN, 1);
1677 	/* Prefetch threshold 2 => fetch when descriptor cache half empty */
1678 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_PREF_THRESHOLD, 2);
1679 	/* Disable hardware watchdog which can misfire */
1680 	EFX_SET_OWORD_FIELD(temp, FRF_AZ_TX_PREF_WD_TMR, 0x3fffff);
1681 	/* Squash TX of packets of 16 bytes or less */
1682 	if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0)
1683 		EFX_SET_OWORD_FIELD(temp, FRF_BZ_TX_FLUSH_MIN_LEN_EN, 1);
1684 	efx_writeo(efx, &temp, FR_AZ_TX_RESERVED);
1685 
1686 	if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0) {
1687 		EFX_POPULATE_OWORD_4(temp,
1688 				     /* Default values */
1689 				     FRF_BZ_TX_PACE_SB_NOT_AF, 0x15,
1690 				     FRF_BZ_TX_PACE_SB_AF, 0xb,
1691 				     FRF_BZ_TX_PACE_FB_BASE, 0,
1692 				     /* Allow large pace values in the
1693 				      * fast bin. */
1694 				     FRF_BZ_TX_PACE_BIN_TH,
1695 				     FFE_BZ_TX_PACE_RESERVED);
1696 		efx_writeo(efx, &temp, FR_BZ_TX_PACE);
1697 	}
1698 }
1699 
1700 /* Register dump */
1701 
1702 #define REGISTER_REVISION_A	1
1703 #define REGISTER_REVISION_B	2
1704 #define REGISTER_REVISION_C	3
1705 #define REGISTER_REVISION_Z	3	/* latest revision */
1706 
1707 struct efx_nic_reg {
1708 	u32 offset:24;
1709 	u32 min_revision:2, max_revision:2;
1710 };
1711 
1712 #define REGISTER(name, min_rev, max_rev) {				\
1713 	FR_ ## min_rev ## max_rev ## _ ## name,				\
1714 	REGISTER_REVISION_ ## min_rev, REGISTER_REVISION_ ## max_rev	\
1715 }
1716 #define REGISTER_AA(name) REGISTER(name, A, A)
1717 #define REGISTER_AB(name) REGISTER(name, A, B)
1718 #define REGISTER_AZ(name) REGISTER(name, A, Z)
1719 #define REGISTER_BB(name) REGISTER(name, B, B)
1720 #define REGISTER_BZ(name) REGISTER(name, B, Z)
1721 #define REGISTER_CZ(name) REGISTER(name, C, Z)
1722 
1723 static const struct efx_nic_reg efx_nic_regs[] = {
1724 	REGISTER_AZ(ADR_REGION),
1725 	REGISTER_AZ(INT_EN_KER),
1726 	REGISTER_BZ(INT_EN_CHAR),
1727 	REGISTER_AZ(INT_ADR_KER),
1728 	REGISTER_BZ(INT_ADR_CHAR),
1729 	/* INT_ACK_KER is WO */
1730 	/* INT_ISR0 is RC */
1731 	REGISTER_AZ(HW_INIT),
1732 	REGISTER_CZ(USR_EV_CFG),
1733 	REGISTER_AB(EE_SPI_HCMD),
1734 	REGISTER_AB(EE_SPI_HADR),
1735 	REGISTER_AB(EE_SPI_HDATA),
1736 	REGISTER_AB(EE_BASE_PAGE),
1737 	REGISTER_AB(EE_VPD_CFG0),
1738 	/* EE_VPD_SW_CNTL and EE_VPD_SW_DATA are not used */
1739 	/* PMBX_DBG_IADDR and PBMX_DBG_IDATA are indirect */
1740 	/* PCIE_CORE_INDIRECT is indirect */
1741 	REGISTER_AB(NIC_STAT),
1742 	REGISTER_AB(GPIO_CTL),
1743 	REGISTER_AB(GLB_CTL),
1744 	/* FATAL_INTR_KER and FATAL_INTR_CHAR are partly RC */
1745 	REGISTER_BZ(DP_CTRL),
1746 	REGISTER_AZ(MEM_STAT),
1747 	REGISTER_AZ(CS_DEBUG),
1748 	REGISTER_AZ(ALTERA_BUILD),
1749 	REGISTER_AZ(CSR_SPARE),
1750 	REGISTER_AB(PCIE_SD_CTL0123),
1751 	REGISTER_AB(PCIE_SD_CTL45),
1752 	REGISTER_AB(PCIE_PCS_CTL_STAT),
1753 	/* DEBUG_DATA_OUT is not used */
1754 	/* DRV_EV is WO */
1755 	REGISTER_AZ(EVQ_CTL),
1756 	REGISTER_AZ(EVQ_CNT1),
1757 	REGISTER_AZ(EVQ_CNT2),
1758 	REGISTER_AZ(BUF_TBL_CFG),
1759 	REGISTER_AZ(SRM_RX_DC_CFG),
1760 	REGISTER_AZ(SRM_TX_DC_CFG),
1761 	REGISTER_AZ(SRM_CFG),
1762 	/* BUF_TBL_UPD is WO */
1763 	REGISTER_AZ(SRM_UPD_EVQ),
1764 	REGISTER_AZ(SRAM_PARITY),
1765 	REGISTER_AZ(RX_CFG),
1766 	REGISTER_BZ(RX_FILTER_CTL),
1767 	/* RX_FLUSH_DESCQ is WO */
1768 	REGISTER_AZ(RX_DC_CFG),
1769 	REGISTER_AZ(RX_DC_PF_WM),
1770 	REGISTER_BZ(RX_RSS_TKEY),
1771 	/* RX_NODESC_DROP is RC */
1772 	REGISTER_AA(RX_SELF_RST),
1773 	/* RX_DEBUG, RX_PUSH_DROP are not used */
1774 	REGISTER_CZ(RX_RSS_IPV6_REG1),
1775 	REGISTER_CZ(RX_RSS_IPV6_REG2),
1776 	REGISTER_CZ(RX_RSS_IPV6_REG3),
1777 	/* TX_FLUSH_DESCQ is WO */
1778 	REGISTER_AZ(TX_DC_CFG),
1779 	REGISTER_AA(TX_CHKSM_CFG),
1780 	REGISTER_AZ(TX_CFG),
1781 	/* TX_PUSH_DROP is not used */
1782 	REGISTER_AZ(TX_RESERVED),
1783 	REGISTER_BZ(TX_PACE),
1784 	/* TX_PACE_DROP_QID is RC */
1785 	REGISTER_BB(TX_VLAN),
1786 	REGISTER_BZ(TX_IPFIL_PORTEN),
1787 	REGISTER_AB(MD_TXD),
1788 	REGISTER_AB(MD_RXD),
1789 	REGISTER_AB(MD_CS),
1790 	REGISTER_AB(MD_PHY_ADR),
1791 	REGISTER_AB(MD_ID),
1792 	/* MD_STAT is RC */
1793 	REGISTER_AB(MAC_STAT_DMA),
1794 	REGISTER_AB(MAC_CTRL),
1795 	REGISTER_BB(GEN_MODE),
1796 	REGISTER_AB(MAC_MC_HASH_REG0),
1797 	REGISTER_AB(MAC_MC_HASH_REG1),
1798 	REGISTER_AB(GM_CFG1),
1799 	REGISTER_AB(GM_CFG2),
1800 	/* GM_IPG and GM_HD are not used */
1801 	REGISTER_AB(GM_MAX_FLEN),
1802 	/* GM_TEST is not used */
1803 	REGISTER_AB(GM_ADR1),
1804 	REGISTER_AB(GM_ADR2),
1805 	REGISTER_AB(GMF_CFG0),
1806 	REGISTER_AB(GMF_CFG1),
1807 	REGISTER_AB(GMF_CFG2),
1808 	REGISTER_AB(GMF_CFG3),
1809 	REGISTER_AB(GMF_CFG4),
1810 	REGISTER_AB(GMF_CFG5),
1811 	REGISTER_BB(TX_SRC_MAC_CTL),
1812 	REGISTER_AB(XM_ADR_LO),
1813 	REGISTER_AB(XM_ADR_HI),
1814 	REGISTER_AB(XM_GLB_CFG),
1815 	REGISTER_AB(XM_TX_CFG),
1816 	REGISTER_AB(XM_RX_CFG),
1817 	REGISTER_AB(XM_MGT_INT_MASK),
1818 	REGISTER_AB(XM_FC),
1819 	REGISTER_AB(XM_PAUSE_TIME),
1820 	REGISTER_AB(XM_TX_PARAM),
1821 	REGISTER_AB(XM_RX_PARAM),
1822 	/* XM_MGT_INT_MSK (note no 'A') is RC */
1823 	REGISTER_AB(XX_PWR_RST),
1824 	REGISTER_AB(XX_SD_CTL),
1825 	REGISTER_AB(XX_TXDRV_CTL),
1826 	/* XX_PRBS_CTL, XX_PRBS_CHK and XX_PRBS_ERR are not used */
1827 	/* XX_CORE_STAT is partly RC */
1828 };
1829 
1830 struct efx_nic_reg_table {
1831 	u32 offset:24;
1832 	u32 min_revision:2, max_revision:2;
1833 	u32 step:6, rows:21;
1834 };
1835 
1836 #define REGISTER_TABLE_DIMENSIONS(_, offset, min_rev, max_rev, step, rows) { \
1837 	offset,								\
1838 	REGISTER_REVISION_ ## min_rev, REGISTER_REVISION_ ## max_rev,	\
1839 	step, rows							\
1840 }
1841 #define REGISTER_TABLE(name, min_rev, max_rev) 				\
1842 	REGISTER_TABLE_DIMENSIONS(					\
1843 		name, FR_ ## min_rev ## max_rev ## _ ## name,		\
1844 		min_rev, max_rev,					\
1845 		FR_ ## min_rev ## max_rev ## _ ## name ## _STEP,	\
1846 		FR_ ## min_rev ## max_rev ## _ ## name ## _ROWS)
1847 #define REGISTER_TABLE_AA(name) REGISTER_TABLE(name, A, A)
1848 #define REGISTER_TABLE_AZ(name) REGISTER_TABLE(name, A, Z)
1849 #define REGISTER_TABLE_BB(name) REGISTER_TABLE(name, B, B)
1850 #define REGISTER_TABLE_BZ(name) REGISTER_TABLE(name, B, Z)
1851 #define REGISTER_TABLE_BB_CZ(name)					\
1852 	REGISTER_TABLE_DIMENSIONS(name, FR_BZ_ ## name, B, B,		\
1853 				  FR_BZ_ ## name ## _STEP,		\
1854 				  FR_BB_ ## name ## _ROWS),		\
1855 	REGISTER_TABLE_DIMENSIONS(name, FR_BZ_ ## name, C, Z,		\
1856 				  FR_BZ_ ## name ## _STEP,		\
1857 				  FR_CZ_ ## name ## _ROWS)
1858 #define REGISTER_TABLE_CZ(name) REGISTER_TABLE(name, C, Z)
1859 
1860 static const struct efx_nic_reg_table efx_nic_reg_tables[] = {
1861 	/* DRIVER is not used */
1862 	/* EVQ_RPTR, TIMER_COMMAND, USR_EV and {RX,TX}_DESC_UPD are WO */
1863 	REGISTER_TABLE_BB(TX_IPFIL_TBL),
1864 	REGISTER_TABLE_BB(TX_SRC_MAC_TBL),
1865 	REGISTER_TABLE_AA(RX_DESC_PTR_TBL_KER),
1866 	REGISTER_TABLE_BB_CZ(RX_DESC_PTR_TBL),
1867 	REGISTER_TABLE_AA(TX_DESC_PTR_TBL_KER),
1868 	REGISTER_TABLE_BB_CZ(TX_DESC_PTR_TBL),
1869 	REGISTER_TABLE_AA(EVQ_PTR_TBL_KER),
1870 	REGISTER_TABLE_BB_CZ(EVQ_PTR_TBL),
1871 	/* We can't reasonably read all of the buffer table (up to 8MB!).
1872 	 * However this driver will only use a few entries.  Reading
1873 	 * 1K entries allows for some expansion of queue count and
1874 	 * size before we need to change the version. */
1875 	REGISTER_TABLE_DIMENSIONS(BUF_FULL_TBL_KER, FR_AA_BUF_FULL_TBL_KER,
1876 				  A, A, 8, 1024),
1877 	REGISTER_TABLE_DIMENSIONS(BUF_FULL_TBL, FR_BZ_BUF_FULL_TBL,
1878 				  B, Z, 8, 1024),
1879 	REGISTER_TABLE_CZ(RX_MAC_FILTER_TBL0),
1880 	REGISTER_TABLE_BB_CZ(TIMER_TBL),
1881 	REGISTER_TABLE_BB_CZ(TX_PACE_TBL),
1882 	REGISTER_TABLE_BZ(RX_INDIRECTION_TBL),
1883 	/* TX_FILTER_TBL0 is huge and not used by this driver */
1884 	REGISTER_TABLE_CZ(TX_MAC_FILTER_TBL0),
1885 	REGISTER_TABLE_CZ(MC_TREG_SMEM),
1886 	/* MSIX_PBA_TABLE is not mapped */
1887 	/* SRM_DBG is not mapped (and is redundant with BUF_FLL_TBL) */
1888 	REGISTER_TABLE_BZ(RX_FILTER_TBL0),
1889 };
1890 
efx_nic_get_regs_len(struct efx_nic * efx)1891 size_t efx_nic_get_regs_len(struct efx_nic *efx)
1892 {
1893 	const struct efx_nic_reg *reg;
1894 	const struct efx_nic_reg_table *table;
1895 	size_t len = 0;
1896 
1897 	for (reg = efx_nic_regs;
1898 	     reg < efx_nic_regs + ARRAY_SIZE(efx_nic_regs);
1899 	     reg++)
1900 		if (efx->type->revision >= reg->min_revision &&
1901 		    efx->type->revision <= reg->max_revision)
1902 			len += sizeof(efx_oword_t);
1903 
1904 	for (table = efx_nic_reg_tables;
1905 	     table < efx_nic_reg_tables + ARRAY_SIZE(efx_nic_reg_tables);
1906 	     table++)
1907 		if (efx->type->revision >= table->min_revision &&
1908 		    efx->type->revision <= table->max_revision)
1909 			len += table->rows * min_t(size_t, table->step, 16);
1910 
1911 	return len;
1912 }
1913 
efx_nic_get_regs(struct efx_nic * efx,void * buf)1914 void efx_nic_get_regs(struct efx_nic *efx, void *buf)
1915 {
1916 	const struct efx_nic_reg *reg;
1917 	const struct efx_nic_reg_table *table;
1918 
1919 	for (reg = efx_nic_regs;
1920 	     reg < efx_nic_regs + ARRAY_SIZE(efx_nic_regs);
1921 	     reg++) {
1922 		if (efx->type->revision >= reg->min_revision &&
1923 		    efx->type->revision <= reg->max_revision) {
1924 			efx_reado(efx, (efx_oword_t *)buf, reg->offset);
1925 			buf += sizeof(efx_oword_t);
1926 		}
1927 	}
1928 
1929 	for (table = efx_nic_reg_tables;
1930 	     table < efx_nic_reg_tables + ARRAY_SIZE(efx_nic_reg_tables);
1931 	     table++) {
1932 		size_t size, i;
1933 
1934 		if (!(efx->type->revision >= table->min_revision &&
1935 		      efx->type->revision <= table->max_revision))
1936 			continue;
1937 
1938 		size = min_t(size_t, table->step, 16);
1939 
1940 		if (table->offset >= efx->type->mem_map_size) {
1941 			/* No longer mapped; return dummy data */
1942 			memcpy(buf, "\xde\xc0\xad\xde", 4);
1943 			buf += table->rows * size;
1944 			continue;
1945 		}
1946 
1947 		for (i = 0; i < table->rows; i++) {
1948 			switch (table->step) {
1949 			case 4: /* 32-bit register or SRAM */
1950 				efx_readd_table(efx, buf, table->offset, i);
1951 				break;
1952 			case 8: /* 64-bit SRAM */
1953 				efx_sram_readq(efx,
1954 					       efx->membase + table->offset,
1955 					       buf, i);
1956 				break;
1957 			case 16: /* 128-bit register */
1958 				efx_reado_table(efx, buf, table->offset, i);
1959 				break;
1960 			case 32: /* 128-bit register, interleaved */
1961 				efx_reado_table(efx, buf, table->offset, 2 * i);
1962 				break;
1963 			default:
1964 				WARN_ON(1);
1965 				return;
1966 			}
1967 			buf += size;
1968 		}
1969 	}
1970 }
1971