xref: /dpdk/drivers/common/mlx5/mlx5_common.c (revision 5b2b0bd084c4a7096c512465116c471018e4e42f)
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 /**
90  * Initialization routine for run-time dependency on glue library.
91  */
92 RTE_INIT_PRIO(mlx5_glue_init, CLASS)
93 {
94 	mlx5_glue_constructor();
95 }
96 
97 /**
98  * This function is responsible of initializing the variable
99  *  haswell_broadwell_cpu by checking if the cpu is intel
100  *  and reading the data returned from mlx5_cpu_id().
101  *  since haswell and broadwell cpus don't have improved performance
102  *  when using relaxed ordering we want to check the cpu type before
103  *  before deciding whether to enable RO or not.
104  *  if the cpu is haswell or broadwell the variable will be set to 1
105  *  otherwise it will be 0.
106  */
107 RTE_INIT_PRIO(mlx5_is_haswell_broadwell_cpu, LOG)
108 {
109 #ifdef RTE_ARCH_X86_64
110 	unsigned int broadwell_models[4] = {0x3d, 0x47, 0x4F, 0x56};
111 	unsigned int haswell_models[4] = {0x3c, 0x3f, 0x45, 0x46};
112 	unsigned int i, model, family, brand_id, vendor;
113 	unsigned int signature_intel_ebx = 0x756e6547;
114 	unsigned int extended_model;
115 	unsigned int eax = 0;
116 	unsigned int ebx = 0;
117 	unsigned int ecx = 0;
118 	unsigned int edx = 0;
119 	int max_level;
120 
121 	mlx5_cpu_id(0, &eax, &ebx, &ecx, &edx);
122 	vendor = ebx;
123 	max_level = eax;
124 	if (max_level < 1) {
125 		haswell_broadwell_cpu = 0;
126 		return;
127 	}
128 	mlx5_cpu_id(1, &eax, &ebx, &ecx, &edx);
129 	model = (eax >> 4) & 0x0f;
130 	family = (eax >> 8) & 0x0f;
131 	brand_id = ebx & 0xff;
132 	extended_model = (eax >> 12) & 0xf0;
133 	/* Check if the processor is Haswell or Broadwell */
134 	if (vendor == signature_intel_ebx) {
135 		if (family == 0x06)
136 			model += extended_model;
137 		if (brand_id == 0 && family == 0x6) {
138 			for (i = 0; i < RTE_DIM(broadwell_models); i++)
139 				if (model == broadwell_models[i]) {
140 					haswell_broadwell_cpu = 1;
141 					return;
142 				}
143 			for (i = 0; i < RTE_DIM(haswell_models); i++)
144 				if (model == haswell_models[i]) {
145 					haswell_broadwell_cpu = 1;
146 					return;
147 				}
148 		}
149 	}
150 #endif
151 	haswell_broadwell_cpu = 0;
152 }
153 
154 /**
155  * Allocate page of door-bells and register it using DevX API.
156  *
157  * @param [in] ctx
158  *   Pointer to the device context.
159  *
160  * @return
161  *   Pointer to new page on success, NULL otherwise.
162  */
163 static struct mlx5_devx_dbr_page *
164 mlx5_alloc_dbr_page(void *ctx)
165 {
166 	struct mlx5_devx_dbr_page *page;
167 
168 	/* Allocate space for door-bell page and management data. */
169 	page = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO,
170 			   sizeof(struct mlx5_devx_dbr_page),
171 			   RTE_CACHE_LINE_SIZE, SOCKET_ID_ANY);
172 	if (!page) {
173 		DRV_LOG(ERR, "cannot allocate dbr page");
174 		return NULL;
175 	}
176 	/* Register allocated memory. */
177 	page->umem = mlx5_glue->devx_umem_reg(ctx, page->dbrs,
178 					      MLX5_DBR_PAGE_SIZE, 0);
179 	if (!page->umem) {
180 		DRV_LOG(ERR, "cannot umem reg dbr page");
181 		mlx5_free(page);
182 		return NULL;
183 	}
184 	return page;
185 }
186 
187 /**
188  * Find the next available door-bell, allocate new page if needed.
189  *
190  * @param [in] ctx
191  *   Pointer to device context.
192  * @param [in] head
193  *   Pointer to the head of dbr pages list.
194  * @param [out] dbr_page
195  *   Door-bell page containing the page data.
196  *
197  * @return
198  *   Door-bell address offset on success, a negative error value otherwise.
199  */
200 int64_t
201 mlx5_get_dbr(void *ctx,  struct mlx5_dbr_page_list *head,
202 	     struct mlx5_devx_dbr_page **dbr_page)
203 {
204 	struct mlx5_devx_dbr_page *page = NULL;
205 	uint32_t i, j;
206 
207 	LIST_FOREACH(page, head, next)
208 		if (page->dbr_count < MLX5_DBR_PER_PAGE)
209 			break;
210 	if (!page) { /* No page with free door-bell exists. */
211 		page = mlx5_alloc_dbr_page(ctx);
212 		if (!page) /* Failed to allocate new page. */
213 			return (-1);
214 		LIST_INSERT_HEAD(head, page, next);
215 	}
216 	/* Loop to find bitmap part with clear bit. */
217 	for (i = 0;
218 	     i < MLX5_DBR_BITMAP_SIZE && page->dbr_bitmap[i] == UINT64_MAX;
219 	     i++)
220 		; /* Empty. */
221 	/* Find the first clear bit. */
222 	MLX5_ASSERT(i < MLX5_DBR_BITMAP_SIZE);
223 	j = rte_bsf64(~page->dbr_bitmap[i]);
224 	page->dbr_bitmap[i] |= (UINT64_C(1) << j);
225 	page->dbr_count++;
226 	*dbr_page = page;
227 	return (((i * 64) + j) * sizeof(uint64_t));
228 }
229 
230 /**
231  * Release a door-bell record.
232  *
233  * @param [in] head
234  *   Pointer to the head of dbr pages list.
235  * @param [in] umem_id
236  *   UMEM ID of page containing the door-bell record to release.
237  * @param [in] offset
238  *   Offset of door-bell record in page.
239  *
240  * @return
241  *   0 on success, a negative error value otherwise.
242  */
243 int32_t
244 mlx5_release_dbr(struct mlx5_dbr_page_list *head, uint32_t umem_id,
245 		 uint64_t offset)
246 {
247 	struct mlx5_devx_dbr_page *page = NULL;
248 	int ret = 0;
249 
250 	LIST_FOREACH(page, head, next)
251 		/* Find the page this address belongs to. */
252 		if (mlx5_os_get_umem_id(page->umem) == umem_id)
253 			break;
254 	if (!page)
255 		return -EINVAL;
256 	page->dbr_count--;
257 	if (!page->dbr_count) {
258 		/* Page not used, free it and remove from list. */
259 		LIST_REMOVE(page, next);
260 		if (page->umem)
261 			ret = -mlx5_glue->devx_umem_dereg(page->umem);
262 		mlx5_free(page);
263 	} else {
264 		/* Mark in bitmap that this door-bell is not in use. */
265 		offset /= MLX5_DBR_SIZE;
266 		int i = offset / 64;
267 		int j = offset % 64;
268 
269 		page->dbr_bitmap[i] &= ~(UINT64_C(1) << j);
270 	}
271 	return ret;
272 }
273