xref: /linux/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c (revision 8be4d31cb8aaeea27bde4b7ddb26e28a89062ebf)
1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /* Copyright (c) 2019 Mellanox Technologies. */
3 
4 #include <linux/pci.h>
5 #include <linux/interrupt.h>
6 #include <linux/notifier.h>
7 #include <linux/mlx5/driver.h>
8 #include <linux/mlx5/vport.h>
9 #include "mlx5_core.h"
10 #include "mlx5_irq.h"
11 #include "pci_irq.h"
12 #include "lib/sf.h"
13 #include "lib/eq.h"
14 #ifdef CONFIG_RFS_ACCEL
15 #include <linux/cpu_rmap.h>
16 #endif
17 
18 #define MLX5_SFS_PER_CTRL_IRQ 64
19 #define MLX5_MAX_MSIX_PER_SF 256
20 #define MLX5_IRQ_CTRL_SF_MAX 8
21 /* min num of vectors for SFs to be enabled */
22 #define MLX5_IRQ_VEC_COMP_BASE_SF 2
23 #define MLX5_IRQ_VEC_COMP_BASE 1
24 
25 #define MLX5_EQ_SHARE_IRQ_MAX_COMP (8)
26 #define MLX5_EQ_SHARE_IRQ_MAX_CTRL (UINT_MAX)
27 #define MLX5_EQ_SHARE_IRQ_MIN_COMP (1)
28 #define MLX5_EQ_SHARE_IRQ_MIN_CTRL (4)
29 
30 struct mlx5_irq {
31 	struct atomic_notifier_head nh;
32 	cpumask_var_t mask;
33 	char name[MLX5_MAX_IRQ_FORMATTED_NAME];
34 	struct mlx5_irq_pool *pool;
35 	int refcount;
36 	struct msi_map map;
37 	u32 pool_index;
38 };
39 
40 struct mlx5_irq_table {
41 	struct mlx5_irq_pool *pcif_pool;
42 	struct mlx5_irq_pool *sf_ctrl_pool;
43 	struct mlx5_irq_pool *sf_comp_pool;
44 };
45 
mlx5_core_func_to_vport(const struct mlx5_core_dev * dev,int func,bool ec_vf_func)46 static int mlx5_core_func_to_vport(const struct mlx5_core_dev *dev,
47 				   int func,
48 				   bool ec_vf_func)
49 {
50 	if (!ec_vf_func)
51 		return func;
52 	return mlx5_core_ec_vf_vport_base(dev) + func - 1;
53 }
54 
55 /**
56  * mlx5_get_default_msix_vec_count - Get the default number of MSI-X vectors
57  *                                   to be ssigned to each VF.
58  * @dev: PF to work on
59  * @num_vfs: Number of enabled VFs
60  */
mlx5_get_default_msix_vec_count(struct mlx5_core_dev * dev,int num_vfs)61 int mlx5_get_default_msix_vec_count(struct mlx5_core_dev *dev, int num_vfs)
62 {
63 	int num_vf_msix, min_msix, max_msix;
64 
65 	num_vf_msix = MLX5_CAP_GEN_MAX(dev, num_total_dynamic_vf_msix);
66 	if (!num_vf_msix)
67 		return 0;
68 
69 	min_msix = MLX5_CAP_GEN(dev, min_dynamic_vf_msix_table_size);
70 	max_msix = MLX5_CAP_GEN(dev, max_dynamic_vf_msix_table_size);
71 
72 	/* Limit maximum number of MSI-X vectors so the default configuration
73 	 * has some available in the pool. This will allow the user to increase
74 	 * the number of vectors in a VF without having to first size-down other
75 	 * VFs.
76 	 */
77 	return max(min(num_vf_msix / num_vfs, max_msix / 2), min_msix);
78 }
79 
80 /**
81  * mlx5_set_msix_vec_count - Set dynamically allocated MSI-X on the VF
82  * @dev: PF to work on
83  * @function_id: Internal PCI VF function IDd
84  * @msix_vec_count: Number of MSI-X vectors to set
85  */
mlx5_set_msix_vec_count(struct mlx5_core_dev * dev,int function_id,int msix_vec_count)86 int mlx5_set_msix_vec_count(struct mlx5_core_dev *dev, int function_id,
87 			    int msix_vec_count)
88 {
89 	int query_sz = MLX5_ST_SZ_BYTES(query_hca_cap_out);
90 	int set_sz = MLX5_ST_SZ_BYTES(set_hca_cap_in);
91 	void *hca_cap = NULL, *query_cap = NULL, *cap;
92 	int num_vf_msix, min_msix, max_msix;
93 	bool ec_vf_function;
94 	int vport;
95 	int ret;
96 
97 	num_vf_msix = MLX5_CAP_GEN_MAX(dev, num_total_dynamic_vf_msix);
98 	if (!num_vf_msix)
99 		return 0;
100 
101 	if (!MLX5_CAP_GEN(dev, vport_group_manager) || !mlx5_core_is_pf(dev))
102 		return -EOPNOTSUPP;
103 
104 	min_msix = MLX5_CAP_GEN(dev, min_dynamic_vf_msix_table_size);
105 	max_msix = MLX5_CAP_GEN(dev, max_dynamic_vf_msix_table_size);
106 
107 	if (msix_vec_count < min_msix)
108 		return -EINVAL;
109 
110 	if (msix_vec_count > max_msix)
111 		return -EOVERFLOW;
112 
113 	query_cap = kvzalloc(query_sz, GFP_KERNEL);
114 	hca_cap = kvzalloc(set_sz, GFP_KERNEL);
115 	if (!hca_cap || !query_cap) {
116 		ret = -ENOMEM;
117 		goto out;
118 	}
119 
120 	ec_vf_function = mlx5_core_ec_sriov_enabled(dev);
121 	vport = mlx5_core_func_to_vport(dev, function_id, ec_vf_function);
122 	ret = mlx5_vport_get_other_func_general_cap(dev, vport, query_cap);
123 	if (ret)
124 		goto out;
125 
126 	cap = MLX5_ADDR_OF(set_hca_cap_in, hca_cap, capability);
127 	memcpy(cap, MLX5_ADDR_OF(query_hca_cap_out, query_cap, capability),
128 	       MLX5_UN_SZ_BYTES(hca_cap_union));
129 	MLX5_SET(cmd_hca_cap, cap, dynamic_msix_table_size, msix_vec_count);
130 
131 	MLX5_SET(set_hca_cap_in, hca_cap, opcode, MLX5_CMD_OP_SET_HCA_CAP);
132 	MLX5_SET(set_hca_cap_in, hca_cap, other_function, 1);
133 	MLX5_SET(set_hca_cap_in, hca_cap, ec_vf_function, ec_vf_function);
134 	MLX5_SET(set_hca_cap_in, hca_cap, function_id, function_id);
135 
136 	MLX5_SET(set_hca_cap_in, hca_cap, op_mod,
137 		 MLX5_SET_HCA_CAP_OP_MOD_GENERAL_DEVICE << 1);
138 	ret = mlx5_cmd_exec_in(dev, set_hca_cap, hca_cap);
139 out:
140 	kvfree(hca_cap);
141 	kvfree(query_cap);
142 	return ret;
143 }
144 
145 /* mlx5_system_free_irq - Free an IRQ
146  * @irq: IRQ to free
147  *
148  * Free the IRQ and other resources such as rmap from the system.
149  * BUT doesn't free or remove reference from mlx5.
150  * This function is very important for the shutdown flow, where we need to
151  * cleanup system resources but keep mlx5 objects alive,
152  * see mlx5_irq_table_free_irqs().
153  */
mlx5_system_free_irq(struct mlx5_irq * irq)154 static void mlx5_system_free_irq(struct mlx5_irq *irq)
155 {
156 	struct mlx5_irq_pool *pool = irq->pool;
157 #ifdef CONFIG_RFS_ACCEL
158 	struct cpu_rmap *rmap;
159 #endif
160 
161 	/* free_irq requires that affinity_hint and rmap will be cleared before
162 	 * calling it. To satisfy this requirement, we call
163 	 * irq_cpu_rmap_remove() to remove the notifier
164 	 */
165 	irq_update_affinity_hint(irq->map.virq, NULL);
166 #ifdef CONFIG_RFS_ACCEL
167 	rmap = mlx5_eq_table_get_rmap(pool->dev);
168 	if (rmap)
169 		irq_cpu_rmap_remove(rmap, irq->map.virq);
170 #endif
171 
172 	free_irq(irq->map.virq, &irq->nh);
173 	if (irq->map.index && pci_msix_can_alloc_dyn(pool->dev->pdev))
174 		pci_msix_free_irq(pool->dev->pdev, irq->map);
175 }
176 
irq_release(struct mlx5_irq * irq)177 static void irq_release(struct mlx5_irq *irq)
178 {
179 	struct mlx5_irq_pool *pool = irq->pool;
180 
181 	xa_erase(&pool->irqs, irq->pool_index);
182 	mlx5_system_free_irq(irq);
183 	free_cpumask_var(irq->mask);
184 	kfree(irq);
185 }
186 
mlx5_irq_put(struct mlx5_irq * irq)187 int mlx5_irq_put(struct mlx5_irq *irq)
188 {
189 	struct mlx5_irq_pool *pool = irq->pool;
190 	int ret = 0;
191 
192 	mutex_lock(&pool->lock);
193 	irq->refcount--;
194 	if (!irq->refcount) {
195 		irq_release(irq);
196 		ret = 1;
197 	}
198 	mutex_unlock(&pool->lock);
199 	return ret;
200 }
201 
mlx5_irq_read_locked(struct mlx5_irq * irq)202 int mlx5_irq_read_locked(struct mlx5_irq *irq)
203 {
204 	lockdep_assert_held(&irq->pool->lock);
205 	return irq->refcount;
206 }
207 
mlx5_irq_get_locked(struct mlx5_irq * irq)208 int mlx5_irq_get_locked(struct mlx5_irq *irq)
209 {
210 	lockdep_assert_held(&irq->pool->lock);
211 	if (WARN_ON_ONCE(!irq->refcount))
212 		return 0;
213 	irq->refcount++;
214 	return 1;
215 }
216 
irq_get(struct mlx5_irq * irq)217 static int irq_get(struct mlx5_irq *irq)
218 {
219 	int err;
220 
221 	mutex_lock(&irq->pool->lock);
222 	err = mlx5_irq_get_locked(irq);
223 	mutex_unlock(&irq->pool->lock);
224 	return err;
225 }
226 
irq_int_handler(int irq,void * nh)227 static irqreturn_t irq_int_handler(int irq, void *nh)
228 {
229 	atomic_notifier_call_chain(nh, 0, NULL);
230 	return IRQ_HANDLED;
231 }
232 
irq_sf_set_name(struct mlx5_irq_pool * pool,char * name,int vecidx)233 static void irq_sf_set_name(struct mlx5_irq_pool *pool, char *name, int vecidx)
234 {
235 	snprintf(name, MLX5_MAX_IRQ_NAME, "%s%d", pool->name, vecidx);
236 }
237 
irq_set_name(struct mlx5_irq_pool * pool,char * name,int vecidx)238 static void irq_set_name(struct mlx5_irq_pool *pool, char *name, int vecidx)
239 {
240 	if (!pool->xa_num_irqs.max) {
241 		/* in case we only have a single irq for the device */
242 		snprintf(name, MLX5_MAX_IRQ_NAME, "mlx5_combined%d", vecidx);
243 		return;
244 	}
245 
246 	if (!vecidx) {
247 		snprintf(name, MLX5_MAX_IRQ_NAME, "mlx5_async%d", vecidx);
248 		return;
249 	}
250 
251 	vecidx -= MLX5_IRQ_VEC_COMP_BASE;
252 	snprintf(name, MLX5_MAX_IRQ_NAME, "mlx5_comp%d", vecidx);
253 }
254 
mlx5_irq_alloc(struct mlx5_irq_pool * pool,int i,struct irq_affinity_desc * af_desc,struct cpu_rmap ** rmap)255 struct mlx5_irq *mlx5_irq_alloc(struct mlx5_irq_pool *pool, int i,
256 				struct irq_affinity_desc *af_desc,
257 				struct cpu_rmap **rmap)
258 {
259 	struct mlx5_core_dev *dev = pool->dev;
260 	char name[MLX5_MAX_IRQ_NAME];
261 	struct mlx5_irq *irq;
262 	int err;
263 
264 	irq = kzalloc(sizeof(*irq), GFP_KERNEL);
265 	if (!irq || !zalloc_cpumask_var(&irq->mask, GFP_KERNEL)) {
266 		kfree(irq);
267 		return ERR_PTR(-ENOMEM);
268 	}
269 
270 	if (!i || !pci_msix_can_alloc_dyn(dev->pdev)) {
271 		/* The vector at index 0 is always statically allocated. If
272 		 * dynamic irq is not supported all vectors are statically
273 		 * allocated. In both cases just get the irq number and set
274 		 * the index.
275 		 */
276 		irq->map.virq = pci_irq_vector(dev->pdev, i);
277 		irq->map.index = i;
278 	} else {
279 		irq->map = pci_msix_alloc_irq_at(dev->pdev, MSI_ANY_INDEX, af_desc);
280 		if (!irq->map.virq) {
281 			err = irq->map.index;
282 			goto err_alloc_irq;
283 		}
284 	}
285 
286 	if (i && rmap && *rmap) {
287 #ifdef CONFIG_RFS_ACCEL
288 		err = irq_cpu_rmap_add(*rmap, irq->map.virq);
289 		if (err)
290 			goto err_irq_rmap;
291 #endif
292 	}
293 	if (!mlx5_irq_pool_is_sf_pool(pool))
294 		irq_set_name(pool, name, i);
295 	else
296 		irq_sf_set_name(pool, name, i);
297 	ATOMIC_INIT_NOTIFIER_HEAD(&irq->nh);
298 	snprintf(irq->name, MLX5_MAX_IRQ_FORMATTED_NAME,
299 		 MLX5_IRQ_NAME_FORMAT_STR, name, pci_name(dev->pdev));
300 	err = request_irq(irq->map.virq, irq_int_handler, 0, irq->name,
301 			  &irq->nh);
302 	if (err) {
303 		mlx5_core_err(dev, "Failed to request irq. err = %d\n", err);
304 		goto err_req_irq;
305 	}
306 
307 	if (af_desc) {
308 		cpumask_copy(irq->mask, &af_desc->mask);
309 		irq_set_affinity_and_hint(irq->map.virq, irq->mask);
310 	}
311 	irq->pool = pool;
312 	irq->refcount = 1;
313 	irq->pool_index = i;
314 	err = xa_err(xa_store(&pool->irqs, irq->pool_index, irq, GFP_KERNEL));
315 	if (err) {
316 		mlx5_core_err(dev, "Failed to alloc xa entry for irq(%u). err = %d\n",
317 			      irq->pool_index, err);
318 		goto err_xa;
319 	}
320 	return irq;
321 err_xa:
322 	if (af_desc)
323 		irq_update_affinity_hint(irq->map.virq, NULL);
324 	free_irq(irq->map.virq, &irq->nh);
325 err_req_irq:
326 #ifdef CONFIG_RFS_ACCEL
327 	if (i && rmap && *rmap) {
328 		free_irq_cpu_rmap(*rmap);
329 		*rmap = NULL;
330 	}
331 err_irq_rmap:
332 #endif
333 	if (i && pci_msix_can_alloc_dyn(dev->pdev))
334 		pci_msix_free_irq(dev->pdev, irq->map);
335 err_alloc_irq:
336 	free_cpumask_var(irq->mask);
337 	kfree(irq);
338 	return ERR_PTR(err);
339 }
340 
mlx5_irq_attach_nb(struct mlx5_irq * irq,struct notifier_block * nb)341 int mlx5_irq_attach_nb(struct mlx5_irq *irq, struct notifier_block *nb)
342 {
343 	int ret;
344 
345 	ret = irq_get(irq);
346 	if (!ret)
347 		/* Something very bad happens here, we are enabling EQ
348 		 * on non-existing IRQ.
349 		 */
350 		return -ENOENT;
351 	ret = atomic_notifier_chain_register(&irq->nh, nb);
352 	if (ret)
353 		mlx5_irq_put(irq);
354 	return ret;
355 }
356 
mlx5_irq_detach_nb(struct mlx5_irq * irq,struct notifier_block * nb)357 int mlx5_irq_detach_nb(struct mlx5_irq *irq, struct notifier_block *nb)
358 {
359 	int err = 0;
360 
361 	err = atomic_notifier_chain_unregister(&irq->nh, nb);
362 	mlx5_irq_put(irq);
363 	return err;
364 }
365 
mlx5_irq_get_affinity_mask(struct mlx5_irq * irq)366 struct cpumask *mlx5_irq_get_affinity_mask(struct mlx5_irq *irq)
367 {
368 	return irq->mask;
369 }
370 
mlx5_irq_get_irq(const struct mlx5_irq * irq)371 int mlx5_irq_get_irq(const struct mlx5_irq *irq)
372 {
373 	return irq->map.virq;
374 }
375 
mlx5_irq_get_index(struct mlx5_irq * irq)376 int mlx5_irq_get_index(struct mlx5_irq *irq)
377 {
378 	return irq->map.index;
379 }
380 
mlx5_irq_get_pool(struct mlx5_irq * irq)381 struct mlx5_irq_pool *mlx5_irq_get_pool(struct mlx5_irq *irq)
382 {
383 	return irq->pool;
384 }
385 
386 /* irq_pool API */
387 
388 /* requesting an irq from a given pool according to given index */
389 static struct mlx5_irq *
irq_pool_request_vector(struct mlx5_irq_pool * pool,int vecidx,struct irq_affinity_desc * af_desc,struct cpu_rmap ** rmap)390 irq_pool_request_vector(struct mlx5_irq_pool *pool, int vecidx,
391 			struct irq_affinity_desc *af_desc,
392 			struct cpu_rmap **rmap)
393 {
394 	struct mlx5_irq *irq;
395 
396 	mutex_lock(&pool->lock);
397 	irq = xa_load(&pool->irqs, vecidx);
398 	if (irq) {
399 		mlx5_irq_get_locked(irq);
400 		goto unlock;
401 	}
402 	irq = mlx5_irq_alloc(pool, vecidx, af_desc, rmap);
403 unlock:
404 	mutex_unlock(&pool->lock);
405 	return irq;
406 }
407 
sf_ctrl_irq_pool_get(struct mlx5_irq_table * irq_table)408 static struct mlx5_irq_pool *sf_ctrl_irq_pool_get(struct mlx5_irq_table *irq_table)
409 {
410 	return irq_table->sf_ctrl_pool;
411 }
412 
413 static struct mlx5_irq_pool *
sf_comp_irq_pool_get(struct mlx5_irq_table * irq_table)414 sf_comp_irq_pool_get(struct mlx5_irq_table *irq_table)
415 {
416 	return irq_table->sf_comp_pool;
417 }
418 
419 struct mlx5_irq_pool *
mlx5_irq_table_get_comp_irq_pool(struct mlx5_core_dev * dev)420 mlx5_irq_table_get_comp_irq_pool(struct mlx5_core_dev *dev)
421 {
422 	struct mlx5_irq_table *irq_table = mlx5_irq_table_get(dev);
423 	struct mlx5_irq_pool *pool = NULL;
424 
425 	if (mlx5_core_is_sf(dev))
426 		pool = sf_comp_irq_pool_get(irq_table);
427 
428 	/* In some configs, there won't be a pool of SFs IRQs. Hence, returning
429 	 * the PF IRQs pool in case the SF pool doesn't exist.
430 	 */
431 	return pool ? pool : irq_table->pcif_pool;
432 }
433 
ctrl_irq_pool_get(struct mlx5_core_dev * dev)434 static struct mlx5_irq_pool *ctrl_irq_pool_get(struct mlx5_core_dev *dev)
435 {
436 	struct mlx5_irq_table *irq_table = mlx5_irq_table_get(dev);
437 	struct mlx5_irq_pool *pool = NULL;
438 
439 	if (mlx5_core_is_sf(dev))
440 		pool = sf_ctrl_irq_pool_get(irq_table);
441 
442 	/* In some configs, there won't be a pool of SFs IRQs. Hence, returning
443 	 * the PF IRQs pool in case the SF pool doesn't exist.
444 	 */
445 	return pool ? pool : irq_table->pcif_pool;
446 }
447 
_mlx5_irq_release(struct mlx5_irq * irq)448 static void _mlx5_irq_release(struct mlx5_irq *irq)
449 {
450 	synchronize_irq(irq->map.virq);
451 	mlx5_irq_put(irq);
452 }
453 
454 /**
455  * mlx5_ctrl_irq_release - release a ctrl IRQ back to the system.
456  * @dev: mlx5 device that releasing the IRQ.
457  * @ctrl_irq: ctrl IRQ to be released.
458  */
mlx5_ctrl_irq_release(struct mlx5_core_dev * dev,struct mlx5_irq * ctrl_irq)459 void mlx5_ctrl_irq_release(struct mlx5_core_dev *dev, struct mlx5_irq *ctrl_irq)
460 {
461 	mlx5_irq_affinity_irq_release(dev, ctrl_irq);
462 }
463 
464 /**
465  * mlx5_ctrl_irq_request - request a ctrl IRQ for mlx5 device.
466  * @dev: mlx5 device that requesting the IRQ.
467  *
468  * This function returns a pointer to IRQ, or ERR_PTR in case of error.
469  */
mlx5_ctrl_irq_request(struct mlx5_core_dev * dev)470 struct mlx5_irq *mlx5_ctrl_irq_request(struct mlx5_core_dev *dev)
471 {
472 	struct mlx5_irq_pool *pool = ctrl_irq_pool_get(dev);
473 	struct irq_affinity_desc *af_desc;
474 	struct mlx5_irq *irq;
475 
476 	af_desc = kvzalloc(sizeof(*af_desc), GFP_KERNEL);
477 	if (!af_desc)
478 		return ERR_PTR(-ENOMEM);
479 
480 	cpumask_copy(&af_desc->mask, cpu_online_mask);
481 	af_desc->is_managed = false;
482 	if (!mlx5_irq_pool_is_sf_pool(pool)) {
483 		/* In case we are allocating a control IRQ from a pci device's pool.
484 		 * This can happen also for a SF if the SFs pool is empty.
485 		 */
486 		if (!pool->xa_num_irqs.max) {
487 			cpumask_clear(&af_desc->mask);
488 			/* In case we only have a single IRQ for PF/VF */
489 			cpumask_set_cpu(cpumask_first(cpu_online_mask), &af_desc->mask);
490 		}
491 		/* Allocate the IRQ in index 0. The vector was already allocated */
492 		irq = irq_pool_request_vector(pool, 0, af_desc, NULL);
493 	} else {
494 		irq = mlx5_irq_affinity_request(dev, pool, af_desc);
495 	}
496 
497 	kvfree(af_desc);
498 
499 	return irq;
500 }
501 
502 /**
503  * mlx5_irq_request - request an IRQ for mlx5 PF/VF device.
504  * @dev: mlx5 device that requesting the IRQ.
505  * @vecidx: vector index of the IRQ. This argument is ignore if affinity is
506  * provided.
507  * @af_desc: affinity descriptor for this IRQ.
508  * @rmap: pointer to reverse map pointer for completion interrupts
509  *
510  * This function returns a pointer to IRQ, or ERR_PTR in case of error.
511  */
mlx5_irq_request(struct mlx5_core_dev * dev,u16 vecidx,struct irq_affinity_desc * af_desc,struct cpu_rmap ** rmap)512 struct mlx5_irq *mlx5_irq_request(struct mlx5_core_dev *dev, u16 vecidx,
513 				  struct irq_affinity_desc *af_desc,
514 				  struct cpu_rmap **rmap)
515 {
516 	struct mlx5_irq_table *irq_table = mlx5_irq_table_get(dev);
517 	struct mlx5_irq_pool *pool;
518 	struct mlx5_irq *irq;
519 
520 	pool = irq_table->pcif_pool;
521 	irq = irq_pool_request_vector(pool, vecidx, af_desc, rmap);
522 	if (IS_ERR(irq))
523 		return irq;
524 	mlx5_core_dbg(dev, "irq %u mapped to cpu %*pbl, %u EQs on this irq\n",
525 		      irq->map.virq, cpumask_pr_args(&af_desc->mask),
526 		      irq->refcount / MLX5_EQ_REFS_PER_IRQ);
527 	return irq;
528 }
529 
530 /**
531  * mlx5_irq_release_vector - release one IRQ back to the system.
532  * @irq: the irq to release.
533  */
mlx5_irq_release_vector(struct mlx5_irq * irq)534 void mlx5_irq_release_vector(struct mlx5_irq *irq)
535 {
536 	_mlx5_irq_release(irq);
537 }
538 
539 /**
540  * mlx5_irq_request_vector - request one IRQ for mlx5 device.
541  * @dev: mlx5 device that is requesting the IRQ.
542  * @cpu: CPU to bind the IRQ to.
543  * @vecidx: vector index to request an IRQ for.
544  * @rmap: pointer to reverse map pointer for completion interrupts
545  *
546  * Each IRQ is bound to at most 1 CPU.
547  * This function is requests one IRQ, for the given @vecidx.
548  *
549  * This function returns a pointer to the irq on success, or an error pointer
550  * in case of an error.
551  */
mlx5_irq_request_vector(struct mlx5_core_dev * dev,u16 cpu,u16 vecidx,struct cpu_rmap ** rmap)552 struct mlx5_irq *mlx5_irq_request_vector(struct mlx5_core_dev *dev, u16 cpu,
553 					 u16 vecidx, struct cpu_rmap **rmap)
554 {
555 	struct mlx5_irq_table *table = mlx5_irq_table_get(dev);
556 	struct mlx5_irq_pool *pool = table->pcif_pool;
557 	int offset = MLX5_IRQ_VEC_COMP_BASE;
558 	struct irq_affinity_desc *af_desc;
559 	struct mlx5_irq *irq;
560 
561 	af_desc = kvzalloc(sizeof(*af_desc), GFP_KERNEL);
562 	if (!af_desc)
563 		return ERR_PTR(-ENOMEM);
564 
565 	if (!pool->xa_num_irqs.max)
566 		offset = 0;
567 
568 	af_desc->is_managed = false;
569 	cpumask_clear(&af_desc->mask);
570 	cpumask_set_cpu(cpu, &af_desc->mask);
571 
572 	irq = mlx5_irq_request(dev, vecidx + offset, af_desc, rmap);
573 
574 	kvfree(af_desc);
575 
576 	return irq;
577 }
578 
579 static struct mlx5_irq_pool *
irq_pool_alloc(struct mlx5_core_dev * dev,int start,int size,char * name,u32 min_threshold,u32 max_threshold)580 irq_pool_alloc(struct mlx5_core_dev *dev, int start, int size, char *name,
581 	       u32 min_threshold, u32 max_threshold)
582 {
583 	struct mlx5_irq_pool *pool = kvzalloc(sizeof(*pool), GFP_KERNEL);
584 
585 	if (!pool)
586 		return ERR_PTR(-ENOMEM);
587 	pool->dev = dev;
588 	mutex_init(&pool->lock);
589 	xa_init_flags(&pool->irqs, XA_FLAGS_ALLOC);
590 	pool->xa_num_irqs.min = start;
591 	pool->xa_num_irqs.max = start + size - 1;
592 	if (name)
593 		snprintf(pool->name, MLX5_MAX_IRQ_NAME - MLX5_MAX_IRQ_IDX_CHARS,
594 			 "%s", name);
595 	pool->min_threshold = min_threshold * MLX5_EQ_REFS_PER_IRQ;
596 	pool->max_threshold = max_threshold * MLX5_EQ_REFS_PER_IRQ;
597 	mlx5_core_dbg(dev, "pool->name = %s, pool->size = %d, pool->start = %d",
598 		      name ? name : "mlx5_pcif_pool", size, start);
599 	return pool;
600 }
601 
irq_pool_free(struct mlx5_irq_pool * pool)602 static void irq_pool_free(struct mlx5_irq_pool *pool)
603 {
604 	struct mlx5_irq *irq;
605 	unsigned long index;
606 
607 	/* There are cases in which we are destroying the irq_table before
608 	 * freeing all the IRQs, fast teardown for example. Hence, free the irqs
609 	 * which might not have been freed.
610 	 */
611 	xa_for_each(&pool->irqs, index, irq)
612 		irq_release(irq);
613 	xa_destroy(&pool->irqs);
614 	mutex_destroy(&pool->lock);
615 	kfree(pool->irqs_per_cpu);
616 	kvfree(pool);
617 }
618 
irq_pools_init(struct mlx5_core_dev * dev,int sf_vec,int pcif_vec,bool dynamic_vec)619 static int irq_pools_init(struct mlx5_core_dev *dev, int sf_vec, int pcif_vec,
620 			  bool dynamic_vec)
621 {
622 	struct mlx5_irq_table *table = dev->priv.irq_table;
623 	int sf_vec_available = sf_vec;
624 	int num_sf_ctrl;
625 	int err;
626 
627 	/* init pcif_pool */
628 	table->pcif_pool = irq_pool_alloc(dev, 0, pcif_vec, NULL,
629 					  MLX5_EQ_SHARE_IRQ_MIN_COMP,
630 					  MLX5_EQ_SHARE_IRQ_MAX_COMP);
631 	if (IS_ERR(table->pcif_pool))
632 		return PTR_ERR(table->pcif_pool);
633 	if (!mlx5_sf_max_functions(dev))
634 		return 0;
635 	if (sf_vec < MLX5_IRQ_VEC_COMP_BASE_SF) {
636 		mlx5_core_dbg(dev, "Not enough IRQs for SFs. SF may run at lower performance\n");
637 		return 0;
638 	}
639 
640 	/* init sf_ctrl_pool */
641 	num_sf_ctrl = DIV_ROUND_UP(mlx5_sf_max_functions(dev),
642 				   MLX5_SFS_PER_CTRL_IRQ);
643 	num_sf_ctrl = min_t(int, MLX5_IRQ_CTRL_SF_MAX, num_sf_ctrl);
644 	if (!dynamic_vec && (num_sf_ctrl + 1) > sf_vec_available) {
645 		mlx5_core_dbg(dev,
646 			      "Not enough IRQs for SFs control and completion pool, required=%d avail=%d\n",
647 			      num_sf_ctrl + 1, sf_vec_available);
648 		return 0;
649 	}
650 
651 	table->sf_ctrl_pool = irq_pool_alloc(dev, pcif_vec, num_sf_ctrl,
652 					     "mlx5_sf_ctrl",
653 					     MLX5_EQ_SHARE_IRQ_MIN_CTRL,
654 					     MLX5_EQ_SHARE_IRQ_MAX_CTRL);
655 	if (IS_ERR(table->sf_ctrl_pool)) {
656 		err = PTR_ERR(table->sf_ctrl_pool);
657 		goto err_pf;
658 	}
659 	sf_vec_available -= num_sf_ctrl;
660 
661 	/* init sf_comp_pool, remaining vectors are for the SF completions */
662 	table->sf_comp_pool = irq_pool_alloc(dev, pcif_vec + num_sf_ctrl,
663 					     sf_vec_available, "mlx5_sf_comp",
664 					     MLX5_EQ_SHARE_IRQ_MIN_COMP,
665 					     MLX5_EQ_SHARE_IRQ_MAX_COMP);
666 	if (IS_ERR(table->sf_comp_pool)) {
667 		err = PTR_ERR(table->sf_comp_pool);
668 		goto err_sf_ctrl;
669 	}
670 
671 	table->sf_comp_pool->irqs_per_cpu = kcalloc(nr_cpu_ids, sizeof(u16), GFP_KERNEL);
672 	if (!table->sf_comp_pool->irqs_per_cpu) {
673 		err = -ENOMEM;
674 		goto err_irqs_per_cpu;
675 	}
676 
677 	return 0;
678 
679 err_irqs_per_cpu:
680 	irq_pool_free(table->sf_comp_pool);
681 err_sf_ctrl:
682 	irq_pool_free(table->sf_ctrl_pool);
683 err_pf:
684 	irq_pool_free(table->pcif_pool);
685 	return err;
686 }
687 
irq_pools_destroy(struct mlx5_irq_table * table)688 static void irq_pools_destroy(struct mlx5_irq_table *table)
689 {
690 	if (table->sf_ctrl_pool) {
691 		irq_pool_free(table->sf_comp_pool);
692 		irq_pool_free(table->sf_ctrl_pool);
693 	}
694 	irq_pool_free(table->pcif_pool);
695 }
696 
mlx5_irq_pool_free_irqs(struct mlx5_irq_pool * pool)697 static void mlx5_irq_pool_free_irqs(struct mlx5_irq_pool *pool)
698 {
699 	struct mlx5_irq *irq;
700 	unsigned long index;
701 
702 	xa_for_each(&pool->irqs, index, irq)
703 		mlx5_system_free_irq(irq);
704 
705 }
706 
mlx5_irq_pools_free_irqs(struct mlx5_irq_table * table)707 static void mlx5_irq_pools_free_irqs(struct mlx5_irq_table *table)
708 {
709 	if (table->sf_ctrl_pool) {
710 		mlx5_irq_pool_free_irqs(table->sf_comp_pool);
711 		mlx5_irq_pool_free_irqs(table->sf_ctrl_pool);
712 	}
713 	mlx5_irq_pool_free_irqs(table->pcif_pool);
714 }
715 
716 /* irq_table API */
717 
mlx5_irq_table_init(struct mlx5_core_dev * dev)718 int mlx5_irq_table_init(struct mlx5_core_dev *dev)
719 {
720 	struct mlx5_irq_table *irq_table;
721 
722 	if (mlx5_core_is_sf(dev))
723 		return 0;
724 
725 	irq_table = kvzalloc_node(sizeof(*irq_table), GFP_KERNEL,
726 				  dev->priv.numa_node);
727 	if (!irq_table)
728 		return -ENOMEM;
729 
730 	dev->priv.irq_table = irq_table;
731 	return 0;
732 }
733 
mlx5_irq_table_cleanup(struct mlx5_core_dev * dev)734 void mlx5_irq_table_cleanup(struct mlx5_core_dev *dev)
735 {
736 	if (mlx5_core_is_sf(dev))
737 		return;
738 
739 	kvfree(dev->priv.irq_table);
740 }
741 
mlx5_irq_table_get_num_comp(struct mlx5_irq_table * table)742 int mlx5_irq_table_get_num_comp(struct mlx5_irq_table *table)
743 {
744 	if (!table->pcif_pool->xa_num_irqs.max)
745 		return 1;
746 	return table->pcif_pool->xa_num_irqs.max - table->pcif_pool->xa_num_irqs.min;
747 }
748 
mlx5_irq_table_create(struct mlx5_core_dev * dev)749 int mlx5_irq_table_create(struct mlx5_core_dev *dev)
750 {
751 	int num_eqs = mlx5_max_eq_cap_get(dev);
752 	bool dynamic_vec;
753 	int total_vec;
754 	int pcif_vec;
755 	int req_vec;
756 	int err;
757 	int n;
758 
759 	if (mlx5_core_is_sf(dev))
760 		return 0;
761 
762 	/* PCI PF vectors usage is limited by online cpus, device EQs and
763 	 * PCI MSI-X capability.
764 	 */
765 	pcif_vec = MLX5_CAP_GEN(dev, num_ports) * num_online_cpus() + 1;
766 	pcif_vec = min_t(int, pcif_vec, num_eqs);
767 	pcif_vec = min_t(int, pcif_vec, pci_msix_vec_count(dev->pdev));
768 
769 	total_vec = pcif_vec;
770 	if (mlx5_sf_max_functions(dev))
771 		total_vec += MLX5_MAX_MSIX_PER_SF * mlx5_sf_max_functions(dev);
772 	total_vec = min_t(int, total_vec, pci_msix_vec_count(dev->pdev));
773 
774 	req_vec = pci_msix_can_alloc_dyn(dev->pdev) ? 1 : total_vec;
775 	n = pci_alloc_irq_vectors(dev->pdev, 1, req_vec, PCI_IRQ_MSIX);
776 	if (n < 0)
777 		return n;
778 
779 	/* Further limit vectors of the pools based on platform for non dynamic case */
780 	dynamic_vec = pci_msix_can_alloc_dyn(dev->pdev);
781 	if (!dynamic_vec) {
782 		pcif_vec = min_t(int, n, pcif_vec);
783 		total_vec = min_t(int, n, total_vec);
784 	}
785 
786 	err = irq_pools_init(dev, total_vec - pcif_vec, pcif_vec, dynamic_vec);
787 	if (err)
788 		pci_free_irq_vectors(dev->pdev);
789 
790 	return err;
791 }
792 
mlx5_irq_table_destroy(struct mlx5_core_dev * dev)793 void mlx5_irq_table_destroy(struct mlx5_core_dev *dev)
794 {
795 	struct mlx5_irq_table *table = dev->priv.irq_table;
796 
797 	if (mlx5_core_is_sf(dev))
798 		return;
799 
800 	/* There are cases where IRQs still will be in used when we reaching
801 	 * to here. Hence, making sure all the irqs are released.
802 	 */
803 	irq_pools_destroy(table);
804 	pci_free_irq_vectors(dev->pdev);
805 }
806 
mlx5_irq_table_free_irqs(struct mlx5_core_dev * dev)807 void mlx5_irq_table_free_irqs(struct mlx5_core_dev *dev)
808 {
809 	struct mlx5_irq_table *table = dev->priv.irq_table;
810 
811 	if (mlx5_core_is_sf(dev))
812 		return;
813 
814 	mlx5_irq_pools_free_irqs(table);
815 	pci_free_irq_vectors(dev->pdev);
816 }
817 
mlx5_irq_table_get_sfs_vec(struct mlx5_irq_table * table)818 int mlx5_irq_table_get_sfs_vec(struct mlx5_irq_table *table)
819 {
820 	if (table->sf_comp_pool)
821 		return min_t(int, num_online_cpus(),
822 			     table->sf_comp_pool->xa_num_irqs.max -
823 			     table->sf_comp_pool->xa_num_irqs.min + 1);
824 	else
825 		return mlx5_irq_table_get_num_comp(table);
826 }
827 
mlx5_irq_table_get(struct mlx5_core_dev * dev)828 struct mlx5_irq_table *mlx5_irq_table_get(struct mlx5_core_dev *dev)
829 {
830 #ifdef CONFIG_MLX5_SF
831 	if (mlx5_core_is_sf(dev))
832 		return dev->priv.parent_mdev->priv.irq_table;
833 #endif
834 	return dev->priv.irq_table;
835 }
836