xref: /openbmc/linux/drivers/crypto/hisilicon/sgl.c (revision bacf743e)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019 HiSilicon Limited. */
3 #include <linux/dma-mapping.h>
4 #include <linux/hisi_acc_qm.h>
5 #include <linux/module.h>
6 #include <linux/slab.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;
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 
70 	/*
71 	 * the pool may allocate a block of memory of size PAGE_SIZE * 2^(MAX_ORDER - 1),
72 	 * block size may exceed 2^31 on ia64, so the max of block size is 2^31
73 	 */
74 	block_size = 1 << (PAGE_SHIFT + MAX_ORDER <= 32 ?
75 			   PAGE_SHIFT + MAX_ORDER - 1 : 31);
76 	sgl_num_per_block = block_size / sgl_size;
77 	block_num = count / sgl_num_per_block;
78 	remain_sgl = count % sgl_num_per_block;
79 
80 	if ((!remain_sgl && block_num > HISI_ACC_MEM_BLOCK_NR) ||
81 	    (remain_sgl > 0 && block_num > HISI_ACC_MEM_BLOCK_NR - 1))
82 		return ERR_PTR(-EINVAL);
83 
84 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
85 	if (!pool)
86 		return ERR_PTR(-ENOMEM);
87 	block = pool->mem_block;
88 
89 	for (i = 0; i < block_num; i++) {
90 		block[i].sgl = dma_alloc_coherent(dev, block_size,
91 						  &block[i].sgl_dma,
92 						  GFP_KERNEL);
93 		if (!block[i].sgl) {
94 			dev_err(dev, "Fail to allocate hw SG buffer!\n");
95 			goto err_free_mem;
96 		}
97 
98 		block[i].size = block_size;
99 	}
100 
101 	if (remain_sgl > 0) {
102 		block[i].sgl = dma_alloc_coherent(dev, remain_sgl * sgl_size,
103 						  &block[i].sgl_dma,
104 						  GFP_KERNEL);
105 		if (!block[i].sgl) {
106 			dev_err(dev, "Fail to allocate remained hw SG buffer!\n");
107 			goto err_free_mem;
108 		}
109 
110 		block[i].size = remain_sgl * sgl_size;
111 	}
112 
113 	pool->sgl_num_per_block = sgl_num_per_block;
114 	pool->block_num = remain_sgl ? block_num + 1 : block_num;
115 	pool->count = count;
116 	pool->sgl_size = sgl_size;
117 	pool->sge_nr = sge_nr;
118 
119 	return pool;
120 
121 err_free_mem:
122 	for (j = 0; j < i; j++) {
123 		dma_free_coherent(dev, block_size, block[j].sgl,
124 				  block[j].sgl_dma);
125 		memset(block + j, 0, sizeof(*block));
126 	}
127 	kfree(pool);
128 	return ERR_PTR(-ENOMEM);
129 }
130 EXPORT_SYMBOL_GPL(hisi_acc_create_sgl_pool);
131 
132 /**
133  * hisi_acc_free_sgl_pool() - Free a hw sgl pool.
134  * @dev: The device which hw sgl pool belongs to.
135  * @pool: Pointer of pool.
136  *
137  * This function frees memory of a hw sgl pool.
138  */
139 void hisi_acc_free_sgl_pool(struct device *dev, struct hisi_acc_sgl_pool *pool)
140 {
141 	struct mem_block *block;
142 	int i;
143 
144 	if (!dev || !pool)
145 		return;
146 
147 	block = pool->mem_block;
148 
149 	for (i = 0; i < pool->block_num; i++)
150 		dma_free_coherent(dev, block[i].size, block[i].sgl,
151 				  block[i].sgl_dma);
152 
153 	kfree(pool);
154 }
155 EXPORT_SYMBOL_GPL(hisi_acc_free_sgl_pool);
156 
157 static struct hisi_acc_hw_sgl *acc_get_sgl(struct hisi_acc_sgl_pool *pool,
158 					   u32 index, dma_addr_t *hw_sgl_dma)
159 {
160 	struct mem_block *block;
161 	u32 block_index, offset;
162 
163 	if (!pool || !hw_sgl_dma || index >= pool->count)
164 		return ERR_PTR(-EINVAL);
165 
166 	block = pool->mem_block;
167 	block_index = index / pool->sgl_num_per_block;
168 	offset = index % pool->sgl_num_per_block;
169 
170 	*hw_sgl_dma = block[block_index].sgl_dma + pool->sgl_size * offset;
171 	return (void *)block[block_index].sgl + pool->sgl_size * offset;
172 }
173 
174 static void sg_map_to_hw_sg(struct scatterlist *sgl,
175 			    struct acc_hw_sge *hw_sge)
176 {
177 	hw_sge->buf = sg_dma_address(sgl);
178 	hw_sge->len = cpu_to_le32(sg_dma_len(sgl));
179 	hw_sge->page_ctrl = sg_virt(sgl);
180 }
181 
182 static void inc_hw_sgl_sge(struct hisi_acc_hw_sgl *hw_sgl)
183 {
184 	u16 var = le16_to_cpu(hw_sgl->entry_sum_in_sgl);
185 
186 	var++;
187 	hw_sgl->entry_sum_in_sgl = cpu_to_le16(var);
188 }
189 
190 static void update_hw_sgl_sum_sge(struct hisi_acc_hw_sgl *hw_sgl, u16 sum)
191 {
192 	hw_sgl->entry_sum_in_chain = cpu_to_le16(sum);
193 }
194 
195 static void clear_hw_sgl_sge(struct hisi_acc_hw_sgl *hw_sgl)
196 {
197 	struct acc_hw_sge *hw_sge = hw_sgl->sge_entries;
198 	int i;
199 
200 	for (i = 0; i < le16_to_cpu(hw_sgl->entry_sum_in_sgl); i++) {
201 		hw_sge[i].page_ctrl = NULL;
202 		hw_sge[i].buf = 0;
203 		hw_sge[i].len = 0;
204 	}
205 }
206 
207 /**
208  * hisi_acc_sg_buf_map_to_hw_sgl - Map a scatterlist to a hw sgl.
209  * @dev: The device which hw sgl belongs to.
210  * @sgl: Scatterlist which will be mapped to hw sgl.
211  * @pool: Pool which hw sgl memory will be allocated in.
212  * @index: Index of hisi_acc_hw_sgl in pool.
213  * @hw_sgl_dma: The dma address of allocated hw sgl.
214  *
215  * This function builds hw sgl according input sgl, user can use hw_sgl_dma
216  * as src/dst in its BD. Only support single hw sgl currently.
217  */
218 struct hisi_acc_hw_sgl *
219 hisi_acc_sg_buf_map_to_hw_sgl(struct device *dev,
220 			      struct scatterlist *sgl,
221 			      struct hisi_acc_sgl_pool *pool,
222 			      u32 index, dma_addr_t *hw_sgl_dma)
223 {
224 	struct hisi_acc_hw_sgl *curr_hw_sgl;
225 	dma_addr_t curr_sgl_dma = 0;
226 	struct acc_hw_sge *curr_hw_sge;
227 	struct scatterlist *sg;
228 	int i, sg_n, sg_n_mapped;
229 
230 	if (!dev || !sgl || !pool || !hw_sgl_dma)
231 		return ERR_PTR(-EINVAL);
232 
233 	sg_n = sg_nents(sgl);
234 
235 	sg_n_mapped = dma_map_sg(dev, sgl, sg_n, DMA_BIDIRECTIONAL);
236 	if (!sg_n_mapped) {
237 		dev_err(dev, "DMA mapping for SG error!\n");
238 		return ERR_PTR(-EINVAL);
239 	}
240 
241 	if (sg_n_mapped > pool->sge_nr) {
242 		dev_err(dev, "the number of entries in input scatterlist is bigger than SGL pool setting.\n");
243 		return ERR_PTR(-EINVAL);
244 	}
245 
246 	curr_hw_sgl = acc_get_sgl(pool, index, &curr_sgl_dma);
247 	if (IS_ERR(curr_hw_sgl)) {
248 		dev_err(dev, "Get SGL error!\n");
249 		dma_unmap_sg(dev, sgl, sg_n, DMA_BIDIRECTIONAL);
250 		return ERR_PTR(-ENOMEM);
251 
252 	}
253 	curr_hw_sgl->entry_length_in_sgl = cpu_to_le16(pool->sge_nr);
254 	curr_hw_sge = curr_hw_sgl->sge_entries;
255 
256 	for_each_sg(sgl, sg, sg_n_mapped, i) {
257 		sg_map_to_hw_sg(sg, curr_hw_sge);
258 		inc_hw_sgl_sge(curr_hw_sgl);
259 		curr_hw_sge++;
260 	}
261 
262 	update_hw_sgl_sum_sge(curr_hw_sgl, pool->sge_nr);
263 	*hw_sgl_dma = curr_sgl_dma;
264 
265 	return curr_hw_sgl;
266 }
267 EXPORT_SYMBOL_GPL(hisi_acc_sg_buf_map_to_hw_sgl);
268 
269 /**
270  * hisi_acc_sg_buf_unmap() - Unmap allocated hw sgl.
271  * @dev: The device which hw sgl belongs to.
272  * @sgl: Related scatterlist.
273  * @hw_sgl: Virtual address of hw sgl.
274  *
275  * This function unmaps allocated hw sgl.
276  */
277 void hisi_acc_sg_buf_unmap(struct device *dev, struct scatterlist *sgl,
278 			   struct hisi_acc_hw_sgl *hw_sgl)
279 {
280 	if (!dev || !sgl || !hw_sgl)
281 		return;
282 
283 	dma_unmap_sg(dev, sgl, sg_nents(sgl), DMA_BIDIRECTIONAL);
284 	clear_hw_sgl_sge(hw_sgl);
285 	hw_sgl->entry_sum_in_chain = 0;
286 	hw_sgl->entry_sum_in_sgl = 0;
287 	hw_sgl->entry_length_in_sgl = 0;
288 }
289 EXPORT_SYMBOL_GPL(hisi_acc_sg_buf_unmap);
290