xref: /linux/drivers/net/ethernet/sfc/nic.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2005-2006 Fen Systems Ltd.
5  * Copyright 2006-2013 Solarflare Communications Inc.
6  */
7 
8 #include <linux/bitops.h>
9 #include <linux/delay.h>
10 #include <linux/interrupt.h>
11 #include <linux/pci.h>
12 #include <linux/module.h>
13 #include <linux/seq_file.h>
14 #include <linux/cpu_rmap.h>
15 #include "net_driver.h"
16 #include "bitfield.h"
17 #include "efx.h"
18 #include "nic.h"
19 #include "ef10_regs.h"
20 #include "io.h"
21 #include "workarounds.h"
22 #include "mcdi_pcol.h"
23 
24 /**************************************************************************
25  *
26  * Generic buffer handling
27  * These buffers are used for interrupt status, MAC stats, etc.
28  *
29  **************************************************************************/
30 
31 int efx_nic_alloc_buffer(struct efx_nic *efx, struct efx_buffer *buffer,
32 			 unsigned int len, gfp_t gfp_flags)
33 {
34 	buffer->addr = dma_alloc_coherent(&efx->pci_dev->dev, len,
35 					  &buffer->dma_addr, gfp_flags);
36 	if (!buffer->addr)
37 		return -ENOMEM;
38 	buffer->len = len;
39 	return 0;
40 }
41 
42 void efx_nic_free_buffer(struct efx_nic *efx, struct efx_buffer *buffer)
43 {
44 	if (buffer->addr) {
45 		dma_free_coherent(&efx->pci_dev->dev, buffer->len,
46 				  buffer->addr, buffer->dma_addr);
47 		buffer->addr = NULL;
48 	}
49 }
50 
51 /* Check whether an event is present in the eventq at the current
52  * read pointer.  Only useful for self-test.
53  */
54 bool efx_nic_event_present(struct efx_channel *channel)
55 {
56 	return efx_event_present(efx_event(channel, channel->eventq_read_ptr));
57 }
58 
59 void efx_nic_event_test_start(struct efx_channel *channel)
60 {
61 	channel->event_test_cpu = -1;
62 	smp_wmb();
63 	channel->efx->type->ev_test_generate(channel);
64 }
65 
66 int efx_nic_irq_test_start(struct efx_nic *efx)
67 {
68 	efx->last_irq_cpu = -1;
69 	smp_wmb();
70 	return efx->type->irq_test_generate(efx);
71 }
72 
73 /* Hook interrupt handler(s)
74  * Try MSI and then legacy interrupts.
75  */
76 int efx_nic_init_interrupt(struct efx_nic *efx)
77 {
78 	struct efx_channel *channel;
79 	unsigned int n_irqs;
80 	int rc;
81 
82 	if (!EFX_INT_MODE_USE_MSI(efx)) {
83 		rc = request_irq(efx->legacy_irq,
84 				 efx->type->irq_handle_legacy, IRQF_SHARED,
85 				 efx->name, efx);
86 		if (rc) {
87 			netif_err(efx, drv, efx->net_dev,
88 				  "failed to hook legacy IRQ %d\n",
89 				  efx->pci_dev->irq);
90 			goto fail1;
91 		}
92 		efx->irqs_hooked = true;
93 		return 0;
94 	}
95 
96 #ifdef CONFIG_RFS_ACCEL
97 	if (efx->interrupt_mode == EFX_INT_MODE_MSIX) {
98 		efx->net_dev->rx_cpu_rmap =
99 			alloc_irq_cpu_rmap(efx->n_rx_channels);
100 		if (!efx->net_dev->rx_cpu_rmap) {
101 			rc = -ENOMEM;
102 			goto fail1;
103 		}
104 	}
105 #endif
106 
107 	/* Hook MSI or MSI-X interrupt */
108 	n_irqs = 0;
109 	efx_for_each_channel(channel, efx) {
110 		rc = request_irq(channel->irq, efx->type->irq_handle_msi,
111 				 IRQF_PROBE_SHARED, /* Not shared */
112 				 efx->msi_context[channel->channel].name,
113 				 &efx->msi_context[channel->channel]);
114 		if (rc) {
115 			netif_err(efx, drv, efx->net_dev,
116 				  "failed to hook IRQ %d\n", channel->irq);
117 			goto fail2;
118 		}
119 		++n_irqs;
120 
121 #ifdef CONFIG_RFS_ACCEL
122 		if (efx->interrupt_mode == EFX_INT_MODE_MSIX &&
123 		    channel->channel < efx->n_rx_channels) {
124 			rc = irq_cpu_rmap_add(efx->net_dev->rx_cpu_rmap,
125 					      channel->irq);
126 			if (rc)
127 				goto fail2;
128 		}
129 #endif
130 	}
131 
132 	efx->irqs_hooked = true;
133 	return 0;
134 
135  fail2:
136 #ifdef CONFIG_RFS_ACCEL
137 	free_irq_cpu_rmap(efx->net_dev->rx_cpu_rmap);
138 	efx->net_dev->rx_cpu_rmap = NULL;
139 #endif
140 	efx_for_each_channel(channel, efx) {
141 		if (n_irqs-- == 0)
142 			break;
143 		free_irq(channel->irq, &efx->msi_context[channel->channel]);
144 	}
145  fail1:
146 	return rc;
147 }
148 
149 void efx_nic_fini_interrupt(struct efx_nic *efx)
150 {
151 	struct efx_channel *channel;
152 
153 #ifdef CONFIG_RFS_ACCEL
154 	free_irq_cpu_rmap(efx->net_dev->rx_cpu_rmap);
155 	efx->net_dev->rx_cpu_rmap = NULL;
156 #endif
157 
158 	if (!efx->irqs_hooked)
159 		return;
160 	if (EFX_INT_MODE_USE_MSI(efx)) {
161 		/* Disable MSI/MSI-X interrupts */
162 		efx_for_each_channel(channel, efx)
163 			free_irq(channel->irq,
164 				 &efx->msi_context[channel->channel]);
165 	} else {
166 		/* Disable legacy interrupt */
167 		free_irq(efx->legacy_irq, efx);
168 	}
169 	efx->irqs_hooked = false;
170 }
171 
172 /* Register dump */
173 
174 #define REGISTER_REVISION_ED	4
175 #define REGISTER_REVISION_EZ	4	/* latest EF10 revision */
176 
177 struct efx_nic_reg {
178 	u32 offset:24;
179 	u32 min_revision:3, max_revision:3;
180 };
181 
182 #define REGISTER(name, arch, min_rev, max_rev) {			\
183 	arch ## R_ ## min_rev ## max_rev ## _ ## name,			\
184 	REGISTER_REVISION_ ## arch ## min_rev,				\
185 	REGISTER_REVISION_ ## arch ## max_rev				\
186 }
187 #define REGISTER_DZ(name) REGISTER(name, E, D, Z)
188 
189 static const struct efx_nic_reg efx_nic_regs[] = {
190 	/* XX_PRBS_CTL, XX_PRBS_CHK and XX_PRBS_ERR are not used */
191 	/* XX_CORE_STAT is partly RC */
192 	REGISTER_DZ(BIU_HW_REV_ID),
193 	REGISTER_DZ(MC_DB_LWRD),
194 	REGISTER_DZ(MC_DB_HWRD),
195 };
196 
197 struct efx_nic_reg_table {
198 	u32 offset:24;
199 	u32 min_revision:3, max_revision:3;
200 	u32 step:6, rows:21;
201 };
202 
203 #define REGISTER_TABLE_DIMENSIONS(_, offset, arch, min_rev, max_rev, step, rows) { \
204 	offset,								\
205 	REGISTER_REVISION_ ## arch ## min_rev,				\
206 	REGISTER_REVISION_ ## arch ## max_rev,				\
207 	step, rows							\
208 }
209 #define REGISTER_TABLE(name, arch, min_rev, max_rev)			\
210 	REGISTER_TABLE_DIMENSIONS(					\
211 		name, arch ## R_ ## min_rev ## max_rev ## _ ## name,	\
212 		arch, min_rev, max_rev,					\
213 		arch ## R_ ## min_rev ## max_rev ## _ ## name ## _STEP,	\
214 		arch ## R_ ## min_rev ## max_rev ## _ ## name ## _ROWS)
215 #define REGISTER_TABLE_DZ(name) REGISTER_TABLE(name, E, D, Z)
216 
217 static const struct efx_nic_reg_table efx_nic_reg_tables[] = {
218 	REGISTER_TABLE_DZ(BIU_MC_SFT_STATUS),
219 };
220 
221 size_t efx_nic_get_regs_len(struct efx_nic *efx)
222 {
223 	const struct efx_nic_reg *reg;
224 	const struct efx_nic_reg_table *table;
225 	size_t len = 0;
226 
227 	for (reg = efx_nic_regs;
228 	     reg < efx_nic_regs + ARRAY_SIZE(efx_nic_regs);
229 	     reg++)
230 		if (efx->type->revision >= reg->min_revision &&
231 		    efx->type->revision <= reg->max_revision)
232 			len += sizeof(efx_oword_t);
233 
234 	for (table = efx_nic_reg_tables;
235 	     table < efx_nic_reg_tables + ARRAY_SIZE(efx_nic_reg_tables);
236 	     table++)
237 		if (efx->type->revision >= table->min_revision &&
238 		    efx->type->revision <= table->max_revision)
239 			len += table->rows * min_t(size_t, table->step, 16);
240 
241 	return len;
242 }
243 
244 void efx_nic_get_regs(struct efx_nic *efx, void *buf)
245 {
246 	const struct efx_nic_reg *reg;
247 	const struct efx_nic_reg_table *table;
248 
249 	for (reg = efx_nic_regs;
250 	     reg < efx_nic_regs + ARRAY_SIZE(efx_nic_regs);
251 	     reg++) {
252 		if (efx->type->revision >= reg->min_revision &&
253 		    efx->type->revision <= reg->max_revision) {
254 			efx_reado(efx, (efx_oword_t *)buf, reg->offset);
255 			buf += sizeof(efx_oword_t);
256 		}
257 	}
258 
259 	for (table = efx_nic_reg_tables;
260 	     table < efx_nic_reg_tables + ARRAY_SIZE(efx_nic_reg_tables);
261 	     table++) {
262 		size_t size, i;
263 
264 		if (!(efx->type->revision >= table->min_revision &&
265 		      efx->type->revision <= table->max_revision))
266 			continue;
267 
268 		size = min_t(size_t, table->step, 16);
269 
270 		for (i = 0; i < table->rows; i++) {
271 			switch (table->step) {
272 			case 4: /* 32-bit SRAM */
273 				efx_readd(efx, buf, table->offset + 4 * i);
274 				break;
275 			case 16: /* 128-bit-readable register */
276 				efx_reado_table(efx, buf, table->offset, i);
277 				break;
278 			case 32: /* 128-bit register, interleaved */
279 				efx_reado_table(efx, buf, table->offset, 2 * i);
280 				break;
281 			default:
282 				WARN_ON(1);
283 				return;
284 			}
285 			buf += size;
286 		}
287 	}
288 }
289 
290 /**
291  * efx_nic_describe_stats - Describe supported statistics for ethtool
292  * @desc: Array of &struct efx_hw_stat_desc describing the statistics
293  * @count: Length of the @desc array
294  * @mask: Bitmask of which elements of @desc are enabled
295  * @names: Buffer to copy names to, or %NULL.  The names are copied
296  *	starting at intervals of %ETH_GSTRING_LEN bytes.
297  *
298  * Returns the number of visible statistics, i.e. the number of set
299  * bits in the first @count bits of @mask for which a name is defined.
300  */
301 size_t efx_nic_describe_stats(const struct efx_hw_stat_desc *desc, size_t count,
302 			      const unsigned long *mask, u8 *names)
303 {
304 	size_t visible = 0;
305 	size_t index;
306 
307 	for_each_set_bit(index, mask, count) {
308 		if (desc[index].name) {
309 			if (names) {
310 				strscpy(names, desc[index].name,
311 					ETH_GSTRING_LEN);
312 				names += ETH_GSTRING_LEN;
313 			}
314 			++visible;
315 		}
316 	}
317 
318 	return visible;
319 }
320 
321 /**
322  * efx_nic_copy_stats - Copy stats from the DMA buffer in to an
323  *	intermediate buffer. This is used to get a consistent
324  *	set of stats while the DMA buffer can be written at any time
325  *	by the NIC.
326  * @efx: The associated NIC.
327  * @dest: Destination buffer. Must be the same size as the DMA buffer.
328  */
329 int efx_nic_copy_stats(struct efx_nic *efx, __le64 *dest)
330 {
331 	__le64 *dma_stats = efx->stats_buffer.addr;
332 	__le64 generation_start, generation_end;
333 	int rc = 0, retry;
334 
335 	if (!dest)
336 		return 0;
337 
338 	if (!dma_stats)
339 		goto return_zeroes;
340 
341 	/* If we're unlucky enough to read statistics during the DMA, wait
342 	 * up to 10ms for it to finish (typically takes <500us)
343 	 */
344 	for (retry = 0; retry < 100; ++retry) {
345 		generation_end = dma_stats[efx->num_mac_stats - 1];
346 		if (generation_end == EFX_MC_STATS_GENERATION_INVALID)
347 			goto return_zeroes;
348 		rmb();
349 		memcpy(dest, dma_stats, efx->num_mac_stats * sizeof(__le64));
350 		rmb();
351 		generation_start = dma_stats[MC_CMD_MAC_GENERATION_START];
352 		if (generation_end == generation_start)
353 			return 0; /* return good data */
354 		udelay(100);
355 	}
356 
357 	rc = -EIO;
358 
359 return_zeroes:
360 	memset(dest, 0, efx->num_mac_stats * sizeof(u64));
361 	return rc;
362 }
363 
364 /**
365  * efx_nic_update_stats - Convert statistics DMA buffer to array of u64
366  * @desc: Array of &struct efx_hw_stat_desc describing the DMA buffer
367  *	layout.  DMA widths of 0, 16, 32 and 64 are supported; where
368  *	the width is specified as 0 the corresponding element of
369  *	@stats is not updated.
370  * @count: Length of the @desc array
371  * @mask: Bitmask of which elements of @desc are enabled
372  * @stats: Buffer to update with the converted statistics.  The length
373  *	of this array must be at least @count.
374  * @dma_buf: DMA buffer containing hardware statistics
375  * @accumulate: If set, the converted values will be added rather than
376  *	directly stored to the corresponding elements of @stats
377  */
378 void efx_nic_update_stats(const struct efx_hw_stat_desc *desc, size_t count,
379 			  const unsigned long *mask,
380 			  u64 *stats, const void *dma_buf, bool accumulate)
381 {
382 	size_t index;
383 
384 	for_each_set_bit(index, mask, count) {
385 		if (desc[index].dma_width) {
386 			const void *addr = dma_buf + desc[index].offset;
387 			u64 val;
388 
389 			switch (desc[index].dma_width) {
390 			case 16:
391 				val = le16_to_cpup((__le16 *)addr);
392 				break;
393 			case 32:
394 				val = le32_to_cpup((__le32 *)addr);
395 				break;
396 			case 64:
397 				val = le64_to_cpup((__le64 *)addr);
398 				break;
399 			default:
400 				WARN_ON(1);
401 				val = 0;
402 				break;
403 			}
404 
405 			if (accumulate)
406 				stats[index] += val;
407 			else
408 				stats[index] = val;
409 		}
410 	}
411 }
412 
413 void efx_nic_fix_nodesc_drop_stat(struct efx_nic *efx, u64 *rx_nodesc_drops)
414 {
415 	/* if down, or this is the first update after coming up */
416 	if (!(efx->net_dev->flags & IFF_UP) || !efx->rx_nodesc_drops_prev_state)
417 		efx->rx_nodesc_drops_while_down +=
418 			*rx_nodesc_drops - efx->rx_nodesc_drops_total;
419 	efx->rx_nodesc_drops_total = *rx_nodesc_drops;
420 	efx->rx_nodesc_drops_prev_state = !!(efx->net_dev->flags & IFF_UP);
421 	*rx_nodesc_drops -= efx->rx_nodesc_drops_while_down;
422 }
423