xref: /openbmc/linux/drivers/crypto/hisilicon/sgl.c (revision 715f23b6)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019 HiSilicon Limited. */
3 #include <linux/dma-mapping.h>
4 #include <linux/module.h>
5 #include <linux/slab.h>
6 #include "qm.h"
7 
8 #define HISI_ACC_SGL_SGE_NR_MIN		1
9 #define HISI_ACC_SGL_NR_MAX		256
10 #define HISI_ACC_SGL_ALIGN_SIZE		64
11 #define HISI_ACC_MEM_BLOCK_NR		5
12 
13 struct acc_hw_sge {
14 	dma_addr_t buf;
15 	void *page_ctrl;
16 	__le32 len;
17 	__le32 pad;
18 	__le32 pad0;
19 	__le32 pad1;
20 };
21 
22 /* use default sgl head size 64B */
23 struct hisi_acc_hw_sgl {
24 	dma_addr_t next_dma;
25 	__le16 entry_sum_in_chain;
26 	__le16 entry_sum_in_sgl;
27 	__le16 entry_length_in_sgl;
28 	__le16 pad0;
29 	__le64 pad1[5];
30 	struct hisi_acc_hw_sgl *next;
31 	struct acc_hw_sge sge_entries[];
32 } __aligned(1);
33 
34 struct hisi_acc_sgl_pool {
35 	struct mem_block {
36 		struct hisi_acc_hw_sgl *sgl;
37 		dma_addr_t sgl_dma;
38 		size_t size;
39 	} mem_block[HISI_ACC_MEM_BLOCK_NR];
40 	u32 sgl_num_per_block;
41 	u32 block_num;
42 	u32 count;
43 	u32 sge_nr;
44 	size_t sgl_size;
45 };
46 
47 /**
48  * hisi_acc_create_sgl_pool() - Create a hw sgl pool.
49  * @dev: The device which hw sgl pool belongs to.
50  * @count: Count of hisi_acc_hw_sgl in pool.
51  * @sge_nr: The count of sge in hw_sgl
52  *
53  * This function creates a hw sgl pool, after this user can get hw sgl memory
54  * from it.
55  */
56 struct hisi_acc_sgl_pool *hisi_acc_create_sgl_pool(struct device *dev,
57 						   u32 count, u32 sge_nr)
58 {
59 	u32 sgl_size, block_size, sgl_num_per_block, block_num, remain_sgl = 0;
60 	struct hisi_acc_sgl_pool *pool;
61 	struct mem_block *block;
62 	u32 i, j;
63 
64 	if (!dev || !count || !sge_nr || sge_nr > HISI_ACC_SGL_SGE_NR_MAX)
65 		return ERR_PTR(-EINVAL);
66 
67 	sgl_size = sizeof(struct acc_hw_sge) * sge_nr +
68 		   sizeof(struct hisi_acc_hw_sgl);
69 	block_size = PAGE_SIZE * (1 << (MAX_ORDER - 1));
70 	sgl_num_per_block = block_size / sgl_size;
71 	block_num = count / sgl_num_per_block;
72 	remain_sgl = count % sgl_num_per_block;
73 
74 	if ((!remain_sgl && block_num > HISI_ACC_MEM_BLOCK_NR) ||
75 	    (remain_sgl > 0 && block_num > HISI_ACC_MEM_BLOCK_NR - 1))
76 		return ERR_PTR(-EINVAL);
77 
78 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
79 	if (!pool)
80 		return ERR_PTR(-ENOMEM);
81 	block = pool->mem_block;
82 
83 	for (i = 0; i < block_num; i++) {
84 		block[i].sgl = dma_alloc_coherent(dev, block_size,
85 						  &block[i].sgl_dma,
86 						  GFP_KERNEL);
87 		if (!block[i].sgl)
88 			goto err_free_mem;
89 
90 		block[i].size = block_size;
91 	}
92 
93 	if (remain_sgl > 0) {
94 		block[i].sgl = dma_alloc_coherent(dev, remain_sgl * sgl_size,
95 						  &block[i].sgl_dma,
96 						  GFP_KERNEL);
97 		if (!block[i].sgl)
98 			goto err_free_mem;
99 
100 		block[i].size = remain_sgl * sgl_size;
101 	}
102 
103 	pool->sgl_num_per_block = sgl_num_per_block;
104 	pool->block_num = remain_sgl ? block_num + 1 : block_num;
105 	pool->count = count;
106 	pool->sgl_size = sgl_size;
107 	pool->sge_nr = sge_nr;
108 
109 	return pool;
110 
111 err_free_mem:
112 	for (j = 0; j < i; j++) {
113 		dma_free_coherent(dev, block_size, block[j].sgl,
114 				  block[j].sgl_dma);
115 		memset(block + j, 0, sizeof(*block));
116 	}
117 	kfree(pool);
118 	return ERR_PTR(-ENOMEM);
119 }
120 EXPORT_SYMBOL_GPL(hisi_acc_create_sgl_pool);
121 
122 /**
123  * hisi_acc_free_sgl_pool() - Free a hw sgl pool.
124  * @dev: The device which hw sgl pool belongs to.
125  * @pool: Pointer of pool.
126  *
127  * This function frees memory of a hw sgl pool.
128  */
129 void hisi_acc_free_sgl_pool(struct device *dev, struct hisi_acc_sgl_pool *pool)
130 {
131 	struct mem_block *block;
132 	int i;
133 
134 	if (!dev || !pool)
135 		return;
136 
137 	block = pool->mem_block;
138 
139 	for (i = 0; i < pool->block_num; i++)
140 		dma_free_coherent(dev, block[i].size, block[i].sgl,
141 				  block[i].sgl_dma);
142 
143 	kfree(pool);
144 }
145 EXPORT_SYMBOL_GPL(hisi_acc_free_sgl_pool);
146 
147 static struct hisi_acc_hw_sgl *acc_get_sgl(struct hisi_acc_sgl_pool *pool,
148 					   u32 index, dma_addr_t *hw_sgl_dma)
149 {
150 	struct mem_block *block;
151 	u32 block_index, offset;
152 
153 	if (!pool || !hw_sgl_dma || index >= pool->count)
154 		return ERR_PTR(-EINVAL);
155 
156 	block = pool->mem_block;
157 	block_index = index / pool->sgl_num_per_block;
158 	offset = index % pool->sgl_num_per_block;
159 
160 	*hw_sgl_dma = block[block_index].sgl_dma + pool->sgl_size * offset;
161 	return (void *)block[block_index].sgl + pool->sgl_size * offset;
162 }
163 
164 static void sg_map_to_hw_sg(struct scatterlist *sgl,
165 			    struct acc_hw_sge *hw_sge)
166 {
167 	hw_sge->buf = sg_dma_address(sgl);
168 	hw_sge->len = cpu_to_le32(sg_dma_len(sgl));
169 }
170 
171 static void inc_hw_sgl_sge(struct hisi_acc_hw_sgl *hw_sgl)
172 {
173 	u16 var = le16_to_cpu(hw_sgl->entry_sum_in_sgl);
174 
175 	var++;
176 	hw_sgl->entry_sum_in_sgl = cpu_to_le16(var);
177 }
178 
179 static void update_hw_sgl_sum_sge(struct hisi_acc_hw_sgl *hw_sgl, u16 sum)
180 {
181 	hw_sgl->entry_sum_in_chain = cpu_to_le16(sum);
182 }
183 
184 /**
185  * hisi_acc_sg_buf_map_to_hw_sgl - Map a scatterlist to a hw sgl.
186  * @dev: The device which hw sgl belongs to.
187  * @sgl: Scatterlist which will be mapped to hw sgl.
188  * @pool: Pool which hw sgl memory will be allocated in.
189  * @index: Index of hisi_acc_hw_sgl in pool.
190  * @hw_sgl_dma: The dma address of allocated hw sgl.
191  *
192  * This function builds hw sgl according input sgl, user can use hw_sgl_dma
193  * as src/dst in its BD. Only support single hw sgl currently.
194  */
195 struct hisi_acc_hw_sgl *
196 hisi_acc_sg_buf_map_to_hw_sgl(struct device *dev,
197 			      struct scatterlist *sgl,
198 			      struct hisi_acc_sgl_pool *pool,
199 			      u32 index, dma_addr_t *hw_sgl_dma)
200 {
201 	struct hisi_acc_hw_sgl *curr_hw_sgl;
202 	dma_addr_t curr_sgl_dma = 0;
203 	struct acc_hw_sge *curr_hw_sge;
204 	struct scatterlist *sg;
205 	int i, ret, sg_n;
206 
207 	if (!dev || !sgl || !pool || !hw_sgl_dma)
208 		return ERR_PTR(-EINVAL);
209 
210 	sg_n = sg_nents(sgl);
211 	if (sg_n > pool->sge_nr)
212 		return ERR_PTR(-EINVAL);
213 
214 	ret = dma_map_sg(dev, sgl, sg_n, DMA_BIDIRECTIONAL);
215 	if (!ret)
216 		return ERR_PTR(-EINVAL);
217 
218 	curr_hw_sgl = acc_get_sgl(pool, index, &curr_sgl_dma);
219 	if (IS_ERR(curr_hw_sgl)) {
220 		dma_unmap_sg(dev, sgl, sg_n, DMA_BIDIRECTIONAL);
221 		return ERR_PTR(-ENOMEM);
222 
223 	}
224 	curr_hw_sgl->entry_length_in_sgl = cpu_to_le16(pool->sge_nr);
225 	curr_hw_sge = curr_hw_sgl->sge_entries;
226 
227 	for_each_sg(sgl, sg, sg_n, i) {
228 		sg_map_to_hw_sg(sg, curr_hw_sge);
229 		inc_hw_sgl_sge(curr_hw_sgl);
230 		curr_hw_sge++;
231 	}
232 
233 	update_hw_sgl_sum_sge(curr_hw_sgl, pool->sge_nr);
234 	*hw_sgl_dma = curr_sgl_dma;
235 
236 	return curr_hw_sgl;
237 }
238 EXPORT_SYMBOL_GPL(hisi_acc_sg_buf_map_to_hw_sgl);
239 
240 /**
241  * hisi_acc_sg_buf_unmap() - Unmap allocated hw sgl.
242  * @dev: The device which hw sgl belongs to.
243  * @sgl: Related scatterlist.
244  * @hw_sgl: Virtual address of hw sgl.
245  * @hw_sgl_dma: DMA address of hw sgl.
246  * @pool: Pool which hw sgl is allocated in.
247  *
248  * This function unmaps allocated hw sgl.
249  */
250 void hisi_acc_sg_buf_unmap(struct device *dev, struct scatterlist *sgl,
251 			   struct hisi_acc_hw_sgl *hw_sgl)
252 {
253 	if (!dev || !sgl || !hw_sgl)
254 		return;
255 
256 	dma_unmap_sg(dev, sgl, sg_nents(sgl), DMA_BIDIRECTIONAL);
257 
258 	hw_sgl->entry_sum_in_chain = 0;
259 	hw_sgl->entry_sum_in_sgl = 0;
260 	hw_sgl->entry_length_in_sgl = 0;
261 }
262 EXPORT_SYMBOL_GPL(hisi_acc_sg_buf_unmap);
263 
264 MODULE_LICENSE("GPL v2");
265 MODULE_AUTHOR("Zhou Wang <wangzhou1@hisilicon.com>");
266 MODULE_DESCRIPTION("HiSilicon Accelerator SGL support");
267