xref: /dpdk/drivers/common/mlx5/mlx5_common.c (revision 82088001631d6255f49df5ecac2ebd2bcfc8126e)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright 2019 Mellanox Technologies, Ltd
3  */
4 
5 #include <unistd.h>
6 #include <string.h>
7 #include <stdio.h>
8 
9 #include <rte_errno.h>
10 #include <rte_mempool.h>
11 #include <rte_malloc.h>
12 
13 #include "mlx5_common.h"
14 #include "mlx5_common_os.h"
15 #include "mlx5_common_utils.h"
16 #include "mlx5_malloc.h"
17 
18 int mlx5_common_logtype;
19 
20 uint8_t haswell_broadwell_cpu;
21 
22 static int
23 mlx5_class_check_handler(__rte_unused const char *key, const char *value,
24 			 void *opaque)
25 {
26 	enum mlx5_class *ret = opaque;
27 
28 	if (strcmp(value, "vdpa") == 0) {
29 		*ret = MLX5_CLASS_VDPA;
30 	} else if (strcmp(value, "net") == 0) {
31 		*ret = MLX5_CLASS_NET;
32 	} else {
33 		DRV_LOG(ERR, "Invalid mlx5 class %s. Maybe typo in device"
34 			" class argument setting?", value);
35 		*ret = MLX5_CLASS_INVALID;
36 	}
37 	return 0;
38 }
39 
40 enum mlx5_class
41 mlx5_class_get(struct rte_devargs *devargs)
42 {
43 	struct rte_kvargs *kvlist;
44 	const char *key = MLX5_CLASS_ARG_NAME;
45 	enum mlx5_class ret = MLX5_CLASS_NET;
46 
47 	if (devargs == NULL)
48 		return ret;
49 	kvlist = rte_kvargs_parse(devargs->args, NULL);
50 	if (kvlist == NULL)
51 		return ret;
52 	if (rte_kvargs_count(kvlist, key))
53 		rte_kvargs_process(kvlist, key, mlx5_class_check_handler, &ret);
54 	rte_kvargs_free(kvlist);
55 	return ret;
56 }
57 
58 
59 /* In case this is an x86_64 intel processor to check if
60  * we should use relaxed ordering.
61  */
62 #ifdef RTE_ARCH_X86_64
63 /**
64  * This function returns processor identification and feature information
65  * into the registers.
66  *
67  * @param eax, ebx, ecx, edx
68  *		Pointers to the registers that will hold cpu information.
69  * @param level
70  *		The main category of information returned.
71  */
72 static inline void mlx5_cpu_id(unsigned int level,
73 				unsigned int *eax, unsigned int *ebx,
74 				unsigned int *ecx, unsigned int *edx)
75 {
76 	__asm__("cpuid\n\t"
77 		: "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx)
78 		: "0" (level));
79 }
80 #endif
81 
82 RTE_INIT_PRIO(mlx5_log_init, LOG)
83 {
84 	mlx5_common_logtype = rte_log_register("pmd.common.mlx5");
85 	if (mlx5_common_logtype >= 0)
86 		rte_log_set_level(mlx5_common_logtype, RTE_LOG_NOTICE);
87 }
88 
89 static bool mlx5_common_initialized;
90 
91 /**
92  * One time innitialization routine for run-time dependency on glue library
93  * for multiple PMDs. Each mlx5 PMD that depends on mlx5_common module,
94  * must invoke in its constructor.
95  */
96 void
97 mlx5_common_init(void)
98 {
99 	if (mlx5_common_initialized)
100 		return;
101 
102 	mlx5_glue_constructor();
103 	mlx5_common_initialized = true;
104 }
105 
106 /**
107  * This function is responsible of initializing the variable
108  *  haswell_broadwell_cpu by checking if the cpu is intel
109  *  and reading the data returned from mlx5_cpu_id().
110  *  since haswell and broadwell cpus don't have improved performance
111  *  when using relaxed ordering we want to check the cpu type before
112  *  before deciding whether to enable RO or not.
113  *  if the cpu is haswell or broadwell the variable will be set to 1
114  *  otherwise it will be 0.
115  */
116 RTE_INIT_PRIO(mlx5_is_haswell_broadwell_cpu, LOG)
117 {
118 #ifdef RTE_ARCH_X86_64
119 	unsigned int broadwell_models[4] = {0x3d, 0x47, 0x4F, 0x56};
120 	unsigned int haswell_models[4] = {0x3c, 0x3f, 0x45, 0x46};
121 	unsigned int i, model, family, brand_id, vendor;
122 	unsigned int signature_intel_ebx = 0x756e6547;
123 	unsigned int extended_model;
124 	unsigned int eax = 0;
125 	unsigned int ebx = 0;
126 	unsigned int ecx = 0;
127 	unsigned int edx = 0;
128 	int max_level;
129 
130 	mlx5_cpu_id(0, &eax, &ebx, &ecx, &edx);
131 	vendor = ebx;
132 	max_level = eax;
133 	if (max_level < 1) {
134 		haswell_broadwell_cpu = 0;
135 		return;
136 	}
137 	mlx5_cpu_id(1, &eax, &ebx, &ecx, &edx);
138 	model = (eax >> 4) & 0x0f;
139 	family = (eax >> 8) & 0x0f;
140 	brand_id = ebx & 0xff;
141 	extended_model = (eax >> 12) & 0xf0;
142 	/* Check if the processor is Haswell or Broadwell */
143 	if (vendor == signature_intel_ebx) {
144 		if (family == 0x06)
145 			model += extended_model;
146 		if (brand_id == 0 && family == 0x6) {
147 			for (i = 0; i < RTE_DIM(broadwell_models); i++)
148 				if (model == broadwell_models[i]) {
149 					haswell_broadwell_cpu = 1;
150 					return;
151 				}
152 			for (i = 0; i < RTE_DIM(haswell_models); i++)
153 				if (model == haswell_models[i]) {
154 					haswell_broadwell_cpu = 1;
155 					return;
156 				}
157 		}
158 	}
159 #endif
160 	haswell_broadwell_cpu = 0;
161 }
162 
163 /**
164  * Allocate page of door-bells and register it using DevX API.
165  *
166  * @param [in] ctx
167  *   Pointer to the device context.
168  *
169  * @return
170  *   Pointer to new page on success, NULL otherwise.
171  */
172 static struct mlx5_devx_dbr_page *
173 mlx5_alloc_dbr_page(void *ctx)
174 {
175 	struct mlx5_devx_dbr_page *page;
176 
177 	/* Allocate space for door-bell page and management data. */
178 	page = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO,
179 			   sizeof(struct mlx5_devx_dbr_page),
180 			   RTE_CACHE_LINE_SIZE, SOCKET_ID_ANY);
181 	if (!page) {
182 		DRV_LOG(ERR, "cannot allocate dbr page");
183 		return NULL;
184 	}
185 	/* Register allocated memory. */
186 	page->umem = mlx5_glue->devx_umem_reg(ctx, page->dbrs,
187 					      MLX5_DBR_PAGE_SIZE, 0);
188 	if (!page->umem) {
189 		DRV_LOG(ERR, "cannot umem reg dbr page");
190 		mlx5_free(page);
191 		return NULL;
192 	}
193 	return page;
194 }
195 
196 /**
197  * Find the next available door-bell, allocate new page if needed.
198  *
199  * @param [in] ctx
200  *   Pointer to device context.
201  * @param [in] head
202  *   Pointer to the head of dbr pages list.
203  * @param [out] dbr_page
204  *   Door-bell page containing the page data.
205  *
206  * @return
207  *   Door-bell address offset on success, a negative error value otherwise.
208  */
209 int64_t
210 mlx5_get_dbr(void *ctx,  struct mlx5_dbr_page_list *head,
211 	     struct mlx5_devx_dbr_page **dbr_page)
212 {
213 	struct mlx5_devx_dbr_page *page = NULL;
214 	uint32_t i, j;
215 
216 	LIST_FOREACH(page, head, next)
217 		if (page->dbr_count < MLX5_DBR_PER_PAGE)
218 			break;
219 	if (!page) { /* No page with free door-bell exists. */
220 		page = mlx5_alloc_dbr_page(ctx);
221 		if (!page) /* Failed to allocate new page. */
222 			return (-1);
223 		LIST_INSERT_HEAD(head, page, next);
224 	}
225 	/* Loop to find bitmap part with clear bit. */
226 	for (i = 0;
227 	     i < MLX5_DBR_BITMAP_SIZE && page->dbr_bitmap[i] == UINT64_MAX;
228 	     i++)
229 		; /* Empty. */
230 	/* Find the first clear bit. */
231 	MLX5_ASSERT(i < MLX5_DBR_BITMAP_SIZE);
232 	j = rte_bsf64(~page->dbr_bitmap[i]);
233 	page->dbr_bitmap[i] |= (UINT64_C(1) << j);
234 	page->dbr_count++;
235 	*dbr_page = page;
236 	return (((i * 64) + j) * sizeof(uint64_t));
237 }
238 
239 /**
240  * Release a door-bell record.
241  *
242  * @param [in] head
243  *   Pointer to the head of dbr pages list.
244  * @param [in] umem_id
245  *   UMEM ID of page containing the door-bell record to release.
246  * @param [in] offset
247  *   Offset of door-bell record in page.
248  *
249  * @return
250  *   0 on success, a negative error value otherwise.
251  */
252 int32_t
253 mlx5_release_dbr(struct mlx5_dbr_page_list *head, uint32_t umem_id,
254 		 uint64_t offset)
255 {
256 	struct mlx5_devx_dbr_page *page = NULL;
257 	int ret = 0;
258 
259 	LIST_FOREACH(page, head, next)
260 		/* Find the page this address belongs to. */
261 		if (mlx5_os_get_umem_id(page->umem) == umem_id)
262 			break;
263 	if (!page)
264 		return -EINVAL;
265 	page->dbr_count--;
266 	if (!page->dbr_count) {
267 		/* Page not used, free it and remove from list. */
268 		LIST_REMOVE(page, next);
269 		if (page->umem)
270 			ret = -mlx5_glue->devx_umem_dereg(page->umem);
271 		mlx5_free(page);
272 	} else {
273 		/* Mark in bitmap that this door-bell is not in use. */
274 		offset /= MLX5_DBR_SIZE;
275 		int i = offset / 64;
276 		int j = offset % 64;
277 
278 		page->dbr_bitmap[i] &= ~(UINT64_C(1) << j);
279 	}
280 	return ret;
281 }
282