1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/kernel.h>
34 #include <linux/io-mapping.h>
35 #include <linux/mlx5/driver.h>
36 #include "mlx5_core.h"
37 
mlx5_cmd_alloc_uar(struct mlx5_core_dev * dev,u32 * uarn)38 static int mlx5_cmd_alloc_uar(struct mlx5_core_dev *dev, u32 *uarn)
39 {
40 	u32 out[MLX5_ST_SZ_DW(alloc_uar_out)] = {};
41 	u32 in[MLX5_ST_SZ_DW(alloc_uar_in)] = {};
42 	int err;
43 
44 	MLX5_SET(alloc_uar_in, in, opcode, MLX5_CMD_OP_ALLOC_UAR);
45 	err = mlx5_cmd_exec_inout(dev, alloc_uar, in, out);
46 	if (err)
47 		return err;
48 
49 	*uarn = MLX5_GET(alloc_uar_out, out, uar);
50 	return 0;
51 }
52 
mlx5_cmd_free_uar(struct mlx5_core_dev * dev,u32 uarn)53 static int mlx5_cmd_free_uar(struct mlx5_core_dev *dev, u32 uarn)
54 {
55 	u32 in[MLX5_ST_SZ_DW(dealloc_uar_in)] = {};
56 
57 	MLX5_SET(dealloc_uar_in, in, opcode, MLX5_CMD_OP_DEALLOC_UAR);
58 	MLX5_SET(dealloc_uar_in, in, uar, uarn);
59 	return mlx5_cmd_exec_in(dev, dealloc_uar, in);
60 }
61 
uars_per_sys_page(struct mlx5_core_dev * mdev)62 static int uars_per_sys_page(struct mlx5_core_dev *mdev)
63 {
64 	if (MLX5_CAP_GEN(mdev, uar_4k))
65 		return MLX5_CAP_GEN(mdev, num_of_uars_per_page);
66 
67 	return 1;
68 }
69 
uar2pfn(struct mlx5_core_dev * mdev,u32 index)70 static u64 uar2pfn(struct mlx5_core_dev *mdev, u32 index)
71 {
72 	u32 system_page_index;
73 
74 	if (MLX5_CAP_GEN(mdev, uar_4k))
75 		system_page_index = index >> (PAGE_SHIFT - MLX5_ADAPTER_PAGE_SHIFT);
76 	else
77 		system_page_index = index;
78 
79 	return (mdev->bar_addr >> PAGE_SHIFT) + system_page_index;
80 }
81 
up_rel_func(struct kref * kref)82 static void up_rel_func(struct kref *kref)
83 {
84 	struct mlx5_uars_page *up = container_of(kref, struct mlx5_uars_page, ref_count);
85 
86 	list_del(&up->list);
87 	iounmap(up->map);
88 	if (mlx5_cmd_free_uar(up->mdev, up->index))
89 		mlx5_core_warn(up->mdev, "failed to free uar index %d\n", up->index);
90 	bitmap_free(up->reg_bitmap);
91 	bitmap_free(up->fp_bitmap);
92 	kfree(up);
93 }
94 
alloc_uars_page(struct mlx5_core_dev * mdev,bool map_wc)95 static struct mlx5_uars_page *alloc_uars_page(struct mlx5_core_dev *mdev,
96 					      bool map_wc)
97 {
98 	struct mlx5_uars_page *up;
99 	int err = -ENOMEM;
100 	phys_addr_t pfn;
101 	int bfregs;
102 	int node;
103 	int i;
104 
105 	bfregs = uars_per_sys_page(mdev) * MLX5_BFREGS_PER_UAR;
106 	node = mdev->priv.numa_node;
107 	up = kzalloc_node(sizeof(*up), GFP_KERNEL, node);
108 	if (!up)
109 		return ERR_PTR(err);
110 
111 	up->mdev = mdev;
112 	up->reg_bitmap = bitmap_zalloc_node(bfregs, GFP_KERNEL, node);
113 	if (!up->reg_bitmap)
114 		goto error1;
115 
116 	up->fp_bitmap = bitmap_zalloc_node(bfregs, GFP_KERNEL, node);
117 	if (!up->fp_bitmap)
118 		goto error1;
119 
120 	for (i = 0; i < bfregs; i++)
121 		if ((i % MLX5_BFREGS_PER_UAR) < MLX5_NON_FP_BFREGS_PER_UAR)
122 			set_bit(i, up->reg_bitmap);
123 		else
124 			set_bit(i, up->fp_bitmap);
125 
126 	up->bfregs = bfregs;
127 	up->fp_avail = bfregs * MLX5_FP_BFREGS_PER_UAR / MLX5_BFREGS_PER_UAR;
128 	up->reg_avail = bfregs * MLX5_NON_FP_BFREGS_PER_UAR / MLX5_BFREGS_PER_UAR;
129 
130 	err = mlx5_cmd_alloc_uar(mdev, &up->index);
131 	if (err) {
132 		mlx5_core_warn(mdev, "mlx5_cmd_alloc_uar() failed, %d\n", err);
133 		goto error1;
134 	}
135 
136 	pfn = uar2pfn(mdev, up->index);
137 	if (map_wc) {
138 		up->map = ioremap_wc(pfn << PAGE_SHIFT, PAGE_SIZE);
139 		if (!up->map) {
140 			err = -EAGAIN;
141 			goto error2;
142 		}
143 	} else {
144 		up->map = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
145 		if (!up->map) {
146 			err = -ENOMEM;
147 			goto error2;
148 		}
149 	}
150 	kref_init(&up->ref_count);
151 	mlx5_core_dbg(mdev, "allocated UAR page: index %d, total bfregs %d\n",
152 		      up->index, up->bfregs);
153 	return up;
154 
155 error2:
156 	if (mlx5_cmd_free_uar(mdev, up->index))
157 		mlx5_core_warn(mdev, "failed to free uar index %d\n", up->index);
158 error1:
159 	bitmap_free(up->fp_bitmap);
160 	bitmap_free(up->reg_bitmap);
161 	kfree(up);
162 	return ERR_PTR(err);
163 }
164 
mlx5_get_uars_page(struct mlx5_core_dev * mdev)165 struct mlx5_uars_page *mlx5_get_uars_page(struct mlx5_core_dev *mdev)
166 {
167 	struct mlx5_uars_page *ret;
168 
169 	mutex_lock(&mdev->priv.bfregs.reg_head.lock);
170 	if (!list_empty(&mdev->priv.bfregs.reg_head.list)) {
171 		ret = list_first_entry(&mdev->priv.bfregs.reg_head.list,
172 				       struct mlx5_uars_page, list);
173 		kref_get(&ret->ref_count);
174 		goto out;
175 	}
176 	ret = alloc_uars_page(mdev, false);
177 	if (IS_ERR(ret))
178 		goto out;
179 	list_add(&ret->list, &mdev->priv.bfregs.reg_head.list);
180 out:
181 	mutex_unlock(&mdev->priv.bfregs.reg_head.lock);
182 
183 	return ret;
184 }
185 EXPORT_SYMBOL(mlx5_get_uars_page);
186 
mlx5_put_uars_page(struct mlx5_core_dev * mdev,struct mlx5_uars_page * up)187 void mlx5_put_uars_page(struct mlx5_core_dev *mdev, struct mlx5_uars_page *up)
188 {
189 	mutex_lock(&mdev->priv.bfregs.reg_head.lock);
190 	kref_put(&up->ref_count, up_rel_func);
191 	mutex_unlock(&mdev->priv.bfregs.reg_head.lock);
192 }
193 EXPORT_SYMBOL(mlx5_put_uars_page);
194 
map_offset(struct mlx5_core_dev * mdev,int dbi)195 static unsigned long map_offset(struct mlx5_core_dev *mdev, int dbi)
196 {
197 	/* return the offset in bytes from the start of the page to the
198 	 * blue flame area of the UAR
199 	 */
200 	return dbi / MLX5_BFREGS_PER_UAR * MLX5_ADAPTER_PAGE_SIZE +
201 	       (dbi % MLX5_BFREGS_PER_UAR) *
202 	       (1 << MLX5_CAP_GEN(mdev, log_bf_reg_size)) + MLX5_BF_OFFSET;
203 }
204 
alloc_bfreg(struct mlx5_core_dev * mdev,struct mlx5_sq_bfreg * bfreg,bool map_wc,bool fast_path)205 static int alloc_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg,
206 		       bool map_wc, bool fast_path)
207 {
208 	struct mlx5_bfreg_data *bfregs;
209 	struct mlx5_uars_page *up;
210 	struct list_head *head;
211 	unsigned long *bitmap;
212 	unsigned int *avail;
213 	struct mutex *lock;  /* pointer to right mutex */
214 	int dbi;
215 
216 	bfregs = &mdev->priv.bfregs;
217 	if (map_wc) {
218 		head = &bfregs->wc_head.list;
219 		lock = &bfregs->wc_head.lock;
220 	} else {
221 		head = &bfregs->reg_head.list;
222 		lock = &bfregs->reg_head.lock;
223 	}
224 	mutex_lock(lock);
225 	if (list_empty(head)) {
226 		up = alloc_uars_page(mdev, map_wc);
227 		if (IS_ERR(up)) {
228 			mutex_unlock(lock);
229 			return PTR_ERR(up);
230 		}
231 		list_add(&up->list, head);
232 	} else {
233 		up = list_entry(head->next, struct mlx5_uars_page, list);
234 		kref_get(&up->ref_count);
235 	}
236 	if (fast_path) {
237 		bitmap = up->fp_bitmap;
238 		avail = &up->fp_avail;
239 	} else {
240 		bitmap = up->reg_bitmap;
241 		avail = &up->reg_avail;
242 	}
243 	dbi = find_first_bit(bitmap, up->bfregs);
244 	clear_bit(dbi, bitmap);
245 	(*avail)--;
246 	if (!(*avail))
247 		list_del(&up->list);
248 
249 	bfreg->map = up->map + map_offset(mdev, dbi);
250 	bfreg->up = up;
251 	bfreg->wc = map_wc;
252 	bfreg->index = up->index + dbi / MLX5_BFREGS_PER_UAR;
253 	mutex_unlock(lock);
254 
255 	return 0;
256 }
257 
mlx5_alloc_bfreg(struct mlx5_core_dev * mdev,struct mlx5_sq_bfreg * bfreg,bool map_wc,bool fast_path)258 int mlx5_alloc_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg,
259 		     bool map_wc, bool fast_path)
260 {
261 	int err;
262 
263 	err = alloc_bfreg(mdev, bfreg, map_wc, fast_path);
264 	if (!err)
265 		return 0;
266 
267 	if (err == -EAGAIN && map_wc)
268 		return alloc_bfreg(mdev, bfreg, false, fast_path);
269 
270 	return err;
271 }
272 EXPORT_SYMBOL(mlx5_alloc_bfreg);
273 
addr_to_dbi_in_syspage(struct mlx5_core_dev * dev,struct mlx5_uars_page * up,struct mlx5_sq_bfreg * bfreg)274 static unsigned int addr_to_dbi_in_syspage(struct mlx5_core_dev *dev,
275 					   struct mlx5_uars_page *up,
276 					   struct mlx5_sq_bfreg *bfreg)
277 {
278 	unsigned int uar_idx;
279 	unsigned int bfreg_idx;
280 	unsigned int bf_reg_size;
281 
282 	bf_reg_size = 1 << MLX5_CAP_GEN(dev, log_bf_reg_size);
283 
284 	uar_idx = (bfreg->map - up->map) >> MLX5_ADAPTER_PAGE_SHIFT;
285 	bfreg_idx = (((uintptr_t)bfreg->map % MLX5_ADAPTER_PAGE_SIZE) - MLX5_BF_OFFSET) / bf_reg_size;
286 
287 	return uar_idx * MLX5_BFREGS_PER_UAR + bfreg_idx;
288 }
289 
mlx5_free_bfreg(struct mlx5_core_dev * mdev,struct mlx5_sq_bfreg * bfreg)290 void mlx5_free_bfreg(struct mlx5_core_dev *mdev, struct mlx5_sq_bfreg *bfreg)
291 {
292 	struct mlx5_bfreg_data *bfregs;
293 	struct mlx5_uars_page *up;
294 	struct mutex *lock; /* pointer to right mutex */
295 	unsigned int dbi;
296 	bool fp;
297 	unsigned int *avail;
298 	unsigned long *bitmap;
299 	struct list_head *head;
300 
301 	bfregs = &mdev->priv.bfregs;
302 	if (bfreg->wc) {
303 		head = &bfregs->wc_head.list;
304 		lock = &bfregs->wc_head.lock;
305 	} else {
306 		head = &bfregs->reg_head.list;
307 		lock = &bfregs->reg_head.lock;
308 	}
309 	up = bfreg->up;
310 	dbi = addr_to_dbi_in_syspage(mdev, up, bfreg);
311 	fp = (dbi % MLX5_BFREGS_PER_UAR) >= MLX5_NON_FP_BFREGS_PER_UAR;
312 	if (fp) {
313 		avail = &up->fp_avail;
314 		bitmap = up->fp_bitmap;
315 	} else {
316 		avail = &up->reg_avail;
317 		bitmap = up->reg_bitmap;
318 	}
319 	mutex_lock(lock);
320 	(*avail)++;
321 	set_bit(dbi, bitmap);
322 	if (*avail == 1)
323 		list_add_tail(&up->list, head);
324 
325 	kref_put(&up->ref_count, up_rel_func);
326 	mutex_unlock(lock);
327 }
328 EXPORT_SYMBOL(mlx5_free_bfreg);
329