xref: /dpdk/drivers/common/mlx5/mlx5_common.c (revision 8a41f4deccc39d3a86c3c91667bee993bfd3e39c)
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 #include "mlx5_common_pci.h"
18 
19 int mlx5_common_logtype;
20 
21 uint8_t haswell_broadwell_cpu;
22 
23 static int
24 mlx5_class_check_handler(__rte_unused const char *key, const char *value,
25 			 void *opaque)
26 {
27 	enum mlx5_class *ret = opaque;
28 
29 	if (strcmp(value, "vdpa") == 0) {
30 		*ret = MLX5_CLASS_VDPA;
31 	} else if (strcmp(value, "net") == 0) {
32 		*ret = MLX5_CLASS_NET;
33 	} else {
34 		DRV_LOG(ERR, "Invalid mlx5 class %s. Maybe typo in device"
35 			" class argument setting?", value);
36 		*ret = MLX5_CLASS_INVALID;
37 	}
38 	return 0;
39 }
40 
41 enum mlx5_class
42 mlx5_class_get(struct rte_devargs *devargs)
43 {
44 	struct rte_kvargs *kvlist;
45 	const char *key = MLX5_CLASS_ARG_NAME;
46 	enum mlx5_class ret = MLX5_CLASS_NET;
47 
48 	if (devargs == NULL)
49 		return ret;
50 	kvlist = rte_kvargs_parse(devargs->args, NULL);
51 	if (kvlist == NULL)
52 		return ret;
53 	if (rte_kvargs_count(kvlist, key))
54 		rte_kvargs_process(kvlist, key, mlx5_class_check_handler, &ret);
55 	rte_kvargs_free(kvlist);
56 	return ret;
57 }
58 
59 
60 /* In case this is an x86_64 intel processor to check if
61  * we should use relaxed ordering.
62  */
63 #ifdef RTE_ARCH_X86_64
64 /**
65  * This function returns processor identification and feature information
66  * into the registers.
67  *
68  * @param eax, ebx, ecx, edx
69  *		Pointers to the registers that will hold cpu information.
70  * @param level
71  *		The main category of information returned.
72  */
73 static inline void mlx5_cpu_id(unsigned int level,
74 				unsigned int *eax, unsigned int *ebx,
75 				unsigned int *ecx, unsigned int *edx)
76 {
77 	__asm__("cpuid\n\t"
78 		: "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx)
79 		: "0" (level));
80 }
81 #endif
82 
83 RTE_INIT_PRIO(mlx5_log_init, LOG)
84 {
85 	mlx5_common_logtype = rte_log_register("pmd.common.mlx5");
86 	if (mlx5_common_logtype >= 0)
87 		rte_log_set_level(mlx5_common_logtype, RTE_LOG_NOTICE);
88 }
89 
90 static bool mlx5_common_initialized;
91 
92 /**
93  * One time innitialization routine for run-time dependency on glue library
94  * for multiple PMDs. Each mlx5 PMD that depends on mlx5_common module,
95  * must invoke in its constructor.
96  */
97 void
98 mlx5_common_init(void)
99 {
100 	if (mlx5_common_initialized)
101 		return;
102 
103 	mlx5_glue_constructor();
104 	mlx5_common_pci_init();
105 	mlx5_common_initialized = true;
106 }
107 
108 /**
109  * This function is responsible of initializing the variable
110  *  haswell_broadwell_cpu by checking if the cpu is intel
111  *  and reading the data returned from mlx5_cpu_id().
112  *  since haswell and broadwell cpus don't have improved performance
113  *  when using relaxed ordering we want to check the cpu type before
114  *  before deciding whether to enable RO or not.
115  *  if the cpu is haswell or broadwell the variable will be set to 1
116  *  otherwise it will be 0.
117  */
118 RTE_INIT_PRIO(mlx5_is_haswell_broadwell_cpu, LOG)
119 {
120 #ifdef RTE_ARCH_X86_64
121 	unsigned int broadwell_models[4] = {0x3d, 0x47, 0x4F, 0x56};
122 	unsigned int haswell_models[4] = {0x3c, 0x3f, 0x45, 0x46};
123 	unsigned int i, model, family, brand_id, vendor;
124 	unsigned int signature_intel_ebx = 0x756e6547;
125 	unsigned int extended_model;
126 	unsigned int eax = 0;
127 	unsigned int ebx = 0;
128 	unsigned int ecx = 0;
129 	unsigned int edx = 0;
130 	int max_level;
131 
132 	mlx5_cpu_id(0, &eax, &ebx, &ecx, &edx);
133 	vendor = ebx;
134 	max_level = eax;
135 	if (max_level < 1) {
136 		haswell_broadwell_cpu = 0;
137 		return;
138 	}
139 	mlx5_cpu_id(1, &eax, &ebx, &ecx, &edx);
140 	model = (eax >> 4) & 0x0f;
141 	family = (eax >> 8) & 0x0f;
142 	brand_id = ebx & 0xff;
143 	extended_model = (eax >> 12) & 0xf0;
144 	/* Check if the processor is Haswell or Broadwell */
145 	if (vendor == signature_intel_ebx) {
146 		if (family == 0x06)
147 			model += extended_model;
148 		if (brand_id == 0 && family == 0x6) {
149 			for (i = 0; i < RTE_DIM(broadwell_models); i++)
150 				if (model == broadwell_models[i]) {
151 					haswell_broadwell_cpu = 1;
152 					return;
153 				}
154 			for (i = 0; i < RTE_DIM(haswell_models); i++)
155 				if (model == haswell_models[i]) {
156 					haswell_broadwell_cpu = 1;
157 					return;
158 				}
159 		}
160 	}
161 #endif
162 	haswell_broadwell_cpu = 0;
163 }
164 
165 /**
166  * Allocate page of door-bells and register it using DevX API.
167  *
168  * @param [in] ctx
169  *   Pointer to the device context.
170  *
171  * @return
172  *   Pointer to new page on success, NULL otherwise.
173  */
174 static struct mlx5_devx_dbr_page *
175 mlx5_alloc_dbr_page(void *ctx)
176 {
177 	struct mlx5_devx_dbr_page *page;
178 
179 	/* Allocate space for door-bell page and management data. */
180 	page = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO,
181 			   sizeof(struct mlx5_devx_dbr_page),
182 			   RTE_CACHE_LINE_SIZE, SOCKET_ID_ANY);
183 	if (!page) {
184 		DRV_LOG(ERR, "cannot allocate dbr page");
185 		return NULL;
186 	}
187 	/* Register allocated memory. */
188 	page->umem = mlx5_glue->devx_umem_reg(ctx, page->dbrs,
189 					      MLX5_DBR_PAGE_SIZE, 0);
190 	if (!page->umem) {
191 		DRV_LOG(ERR, "cannot umem reg dbr page");
192 		mlx5_free(page);
193 		return NULL;
194 	}
195 	return page;
196 }
197 
198 /**
199  * Find the next available door-bell, allocate new page if needed.
200  *
201  * @param [in] ctx
202  *   Pointer to device context.
203  * @param [in] head
204  *   Pointer to the head of dbr pages list.
205  * @param [out] dbr_page
206  *   Door-bell page containing the page data.
207  *
208  * @return
209  *   Door-bell address offset on success, a negative error value otherwise.
210  */
211 int64_t
212 mlx5_get_dbr(void *ctx,  struct mlx5_dbr_page_list *head,
213 	     struct mlx5_devx_dbr_page **dbr_page)
214 {
215 	struct mlx5_devx_dbr_page *page = NULL;
216 	uint32_t i, j;
217 
218 	LIST_FOREACH(page, head, next)
219 		if (page->dbr_count < MLX5_DBR_PER_PAGE)
220 			break;
221 	if (!page) { /* No page with free door-bell exists. */
222 		page = mlx5_alloc_dbr_page(ctx);
223 		if (!page) /* Failed to allocate new page. */
224 			return (-1);
225 		LIST_INSERT_HEAD(head, page, next);
226 	}
227 	/* Loop to find bitmap part with clear bit. */
228 	for (i = 0;
229 	     i < MLX5_DBR_BITMAP_SIZE && page->dbr_bitmap[i] == UINT64_MAX;
230 	     i++)
231 		; /* Empty. */
232 	/* Find the first clear bit. */
233 	MLX5_ASSERT(i < MLX5_DBR_BITMAP_SIZE);
234 	j = rte_bsf64(~page->dbr_bitmap[i]);
235 	page->dbr_bitmap[i] |= (UINT64_C(1) << j);
236 	page->dbr_count++;
237 	*dbr_page = page;
238 	return (((i * 64) + j) * sizeof(uint64_t));
239 }
240 
241 /**
242  * Release a door-bell record.
243  *
244  * @param [in] head
245  *   Pointer to the head of dbr pages list.
246  * @param [in] umem_id
247  *   UMEM ID of page containing the door-bell record to release.
248  * @param [in] offset
249  *   Offset of door-bell record in page.
250  *
251  * @return
252  *   0 on success, a negative error value otherwise.
253  */
254 int32_t
255 mlx5_release_dbr(struct mlx5_dbr_page_list *head, uint32_t umem_id,
256 		 uint64_t offset)
257 {
258 	struct mlx5_devx_dbr_page *page = NULL;
259 	int ret = 0;
260 
261 	LIST_FOREACH(page, head, next)
262 		/* Find the page this address belongs to. */
263 		if (mlx5_os_get_umem_id(page->umem) == umem_id)
264 			break;
265 	if (!page)
266 		return -EINVAL;
267 	page->dbr_count--;
268 	if (!page->dbr_count) {
269 		/* Page not used, free it and remove from list. */
270 		LIST_REMOVE(page, next);
271 		if (page->umem)
272 			ret = -mlx5_glue->devx_umem_dereg(page->umem);
273 		mlx5_free(page);
274 	} else {
275 		/* Mark in bitmap that this door-bell is not in use. */
276 		offset /= MLX5_DBR_SIZE;
277 		int i = offset / 64;
278 		int j = offset % 64;
279 
280 		page->dbr_bitmap[i] &= ~(UINT64_C(1) << j);
281 	}
282 	return ret;
283 }
284