xref: /openbmc/linux/drivers/crypto/hisilicon/sgl.c (revision c9dc580c)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019 HiSilicon Limited. */
3 #include <linux/align.h>
4 #include <linux/dma-mapping.h>
5 #include <linux/hisi_acc_qm.h>
6 #include <linux/module.h>
7 #include <linux/slab.h>
8 
9 #define HISI_ACC_SGL_SGE_NR_MIN		1
10 #define HISI_ACC_SGL_NR_MAX		256
11 #define HISI_ACC_SGL_ALIGN_SIZE		64
12 #define HISI_ACC_MEM_BLOCK_NR		5
13 
14 struct acc_hw_sge {
15 	dma_addr_t buf;
16 	void *page_ctrl;
17 	__le32 len;
18 	__le32 pad;
19 	__le32 pad0;
20 	__le32 pad1;
21 };
22 
23 /* use default sgl head size 64B */
24 struct hisi_acc_hw_sgl {
25 	dma_addr_t next_dma;
26 	__le16 entry_sum_in_chain;
27 	__le16 entry_sum_in_sgl;
28 	__le16 entry_length_in_sgl;
29 	__le16 pad0;
30 	__le64 pad1[5];
31 	struct hisi_acc_hw_sgl *next;
32 	struct acc_hw_sge sge_entries[];
33 } __aligned(1);
34 
35 struct hisi_acc_sgl_pool {
36 	struct mem_block {
37 		struct hisi_acc_hw_sgl *sgl;
38 		dma_addr_t sgl_dma;
39 		size_t size;
40 	} mem_block[HISI_ACC_MEM_BLOCK_NR];
41 	u32 sgl_num_per_block;
42 	u32 block_num;
43 	u32 count;
44 	u32 sge_nr;
45 	size_t sgl_size;
46 };
47 
48 /**
49  * hisi_acc_create_sgl_pool() - Create a hw sgl pool.
50  * @dev: The device which hw sgl pool belongs to.
51  * @count: Count of hisi_acc_hw_sgl in pool.
52  * @sge_nr: The count of sge in hw_sgl
53  *
54  * This function creates a hw sgl pool, after this user can get hw sgl memory
55  * from it.
56  */
57 struct hisi_acc_sgl_pool *hisi_acc_create_sgl_pool(struct device *dev,
58 						   u32 count, u32 sge_nr)
59 {
60 	u32 sgl_size, block_size, sgl_num_per_block, block_num, remain_sgl;
61 	struct hisi_acc_sgl_pool *pool;
62 	struct mem_block *block;
63 	u32 i, j;
64 
65 	if (!dev || !count || !sge_nr || sge_nr > HISI_ACC_SGL_SGE_NR_MAX)
66 		return ERR_PTR(-EINVAL);
67 
68 	sgl_size = ALIGN(sizeof(struct acc_hw_sge) * sge_nr +
69 			 sizeof(struct hisi_acc_hw_sgl),
70 			 HISI_ACC_SGL_ALIGN_SIZE);
71 
72 	/*
73 	 * the pool may allocate a block of memory of size PAGE_SIZE * 2^(MAX_ORDER - 1),
74 	 * block size may exceed 2^31 on ia64, so the max of block size is 2^31
75 	 */
76 	block_size = 1 << (PAGE_SHIFT + MAX_ORDER <= 32 ?
77 			   PAGE_SHIFT + MAX_ORDER - 1 : 31);
78 	sgl_num_per_block = block_size / sgl_size;
79 	block_num = count / sgl_num_per_block;
80 	remain_sgl = count % sgl_num_per_block;
81 
82 	if ((!remain_sgl && block_num > HISI_ACC_MEM_BLOCK_NR) ||
83 	    (remain_sgl > 0 && block_num > HISI_ACC_MEM_BLOCK_NR - 1))
84 		return ERR_PTR(-EINVAL);
85 
86 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
87 	if (!pool)
88 		return ERR_PTR(-ENOMEM);
89 	block = pool->mem_block;
90 
91 	for (i = 0; i < block_num; i++) {
92 		block[i].sgl = dma_alloc_coherent(dev, block_size,
93 						  &block[i].sgl_dma,
94 						  GFP_KERNEL);
95 		if (!block[i].sgl) {
96 			dev_err(dev, "Fail to allocate hw SG buffer!\n");
97 			goto err_free_mem;
98 		}
99 
100 		block[i].size = block_size;
101 	}
102 
103 	if (remain_sgl > 0) {
104 		block[i].sgl = dma_alloc_coherent(dev, remain_sgl * sgl_size,
105 						  &block[i].sgl_dma,
106 						  GFP_KERNEL);
107 		if (!block[i].sgl) {
108 			dev_err(dev, "Fail to allocate remained hw SG buffer!\n");
109 			goto err_free_mem;
110 		}
111 
112 		block[i].size = remain_sgl * sgl_size;
113 	}
114 
115 	pool->sgl_num_per_block = sgl_num_per_block;
116 	pool->block_num = remain_sgl ? block_num + 1 : block_num;
117 	pool->count = count;
118 	pool->sgl_size = sgl_size;
119 	pool->sge_nr = sge_nr;
120 
121 	return pool;
122 
123 err_free_mem:
124 	for (j = 0; j < i; j++) {
125 		dma_free_coherent(dev, block_size, block[j].sgl,
126 				  block[j].sgl_dma);
127 	}
128 	kfree_sensitive(pool);
129 	return ERR_PTR(-ENOMEM);
130 }
131 EXPORT_SYMBOL_GPL(hisi_acc_create_sgl_pool);
132 
133 /**
134  * hisi_acc_free_sgl_pool() - Free a hw sgl pool.
135  * @dev: The device which hw sgl pool belongs to.
136  * @pool: Pointer of pool.
137  *
138  * This function frees memory of a hw sgl pool.
139  */
140 void hisi_acc_free_sgl_pool(struct device *dev, struct hisi_acc_sgl_pool *pool)
141 {
142 	struct mem_block *block;
143 	int i;
144 
145 	if (!dev || !pool)
146 		return;
147 
148 	block = pool->mem_block;
149 
150 	for (i = 0; i < pool->block_num; i++)
151 		dma_free_coherent(dev, block[i].size, block[i].sgl,
152 				  block[i].sgl_dma);
153 
154 	kfree(pool);
155 }
156 EXPORT_SYMBOL_GPL(hisi_acc_free_sgl_pool);
157 
158 static struct hisi_acc_hw_sgl *acc_get_sgl(struct hisi_acc_sgl_pool *pool,
159 					   u32 index, dma_addr_t *hw_sgl_dma)
160 {
161 	struct mem_block *block;
162 	u32 block_index, offset;
163 
164 	if (!pool || !hw_sgl_dma || index >= pool->count)
165 		return ERR_PTR(-EINVAL);
166 
167 	block = pool->mem_block;
168 	block_index = index / pool->sgl_num_per_block;
169 	offset = index % pool->sgl_num_per_block;
170 
171 	*hw_sgl_dma = block[block_index].sgl_dma + pool->sgl_size * offset;
172 	return (void *)block[block_index].sgl + pool->sgl_size * offset;
173 }
174 
175 static void sg_map_to_hw_sg(struct scatterlist *sgl,
176 			    struct acc_hw_sge *hw_sge)
177 {
178 	hw_sge->buf = sg_dma_address(sgl);
179 	hw_sge->len = cpu_to_le32(sg_dma_len(sgl));
180 	hw_sge->page_ctrl = sg_virt(sgl);
181 }
182 
183 static void inc_hw_sgl_sge(struct hisi_acc_hw_sgl *hw_sgl)
184 {
185 	u16 var = le16_to_cpu(hw_sgl->entry_sum_in_sgl);
186 
187 	var++;
188 	hw_sgl->entry_sum_in_sgl = cpu_to_le16(var);
189 }
190 
191 static void update_hw_sgl_sum_sge(struct hisi_acc_hw_sgl *hw_sgl, u16 sum)
192 {
193 	hw_sgl->entry_sum_in_chain = cpu_to_le16(sum);
194 }
195 
196 static void clear_hw_sgl_sge(struct hisi_acc_hw_sgl *hw_sgl)
197 {
198 	struct acc_hw_sge *hw_sge = hw_sgl->sge_entries;
199 	int i;
200 
201 	for (i = 0; i < le16_to_cpu(hw_sgl->entry_sum_in_sgl); i++) {
202 		hw_sge[i].page_ctrl = NULL;
203 		hw_sge[i].buf = 0;
204 		hw_sge[i].len = 0;
205 	}
206 }
207 
208 /**
209  * hisi_acc_sg_buf_map_to_hw_sgl - Map a scatterlist to a hw sgl.
210  * @dev: The device which hw sgl belongs to.
211  * @sgl: Scatterlist which will be mapped to hw sgl.
212  * @pool: Pool which hw sgl memory will be allocated in.
213  * @index: Index of hisi_acc_hw_sgl in pool.
214  * @hw_sgl_dma: The dma address of allocated hw sgl.
215  *
216  * This function builds hw sgl according input sgl, user can use hw_sgl_dma
217  * as src/dst in its BD. Only support single hw sgl currently.
218  */
219 struct hisi_acc_hw_sgl *
220 hisi_acc_sg_buf_map_to_hw_sgl(struct device *dev,
221 			      struct scatterlist *sgl,
222 			      struct hisi_acc_sgl_pool *pool,
223 			      u32 index, dma_addr_t *hw_sgl_dma)
224 {
225 	struct hisi_acc_hw_sgl *curr_hw_sgl;
226 	dma_addr_t curr_sgl_dma = 0;
227 	struct acc_hw_sge *curr_hw_sge;
228 	struct scatterlist *sg;
229 	int i, sg_n, sg_n_mapped;
230 
231 	if (!dev || !sgl || !pool || !hw_sgl_dma)
232 		return ERR_PTR(-EINVAL);
233 
234 	sg_n = sg_nents(sgl);
235 
236 	sg_n_mapped = dma_map_sg(dev, sgl, sg_n, DMA_BIDIRECTIONAL);
237 	if (!sg_n_mapped) {
238 		dev_err(dev, "DMA mapping for SG error!\n");
239 		return ERR_PTR(-EINVAL);
240 	}
241 
242 	if (sg_n_mapped > pool->sge_nr) {
243 		dev_err(dev, "the number of entries in input scatterlist is bigger than SGL pool setting.\n");
244 		return ERR_PTR(-EINVAL);
245 	}
246 
247 	curr_hw_sgl = acc_get_sgl(pool, index, &curr_sgl_dma);
248 	if (IS_ERR(curr_hw_sgl)) {
249 		dev_err(dev, "Get SGL error!\n");
250 		dma_unmap_sg(dev, sgl, sg_n, DMA_BIDIRECTIONAL);
251 		return ERR_PTR(-ENOMEM);
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