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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NVM helpers
4 *
5 * Copyright (C) 2020, Intel Corporation
6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
7 */
8
9#include <linux/idr.h>
10#include <linux/slab.h>
11#include <linux/vmalloc.h>
12
13#include "tb.h"
14
15static DEFINE_IDA(nvm_ida);
16
17/**
18 * tb_nvm_alloc() - Allocate new NVM structure
19 * @dev: Device owning the NVM
20 *
21 * Allocates new NVM structure with unique @id and returns it. In case
22 * of error returns ERR_PTR().
23 */
24struct tb_nvm *tb_nvm_alloc(struct device *dev)
25{
26 struct tb_nvm *nvm;
27 int ret;
28
29 nvm = kzalloc(sizeof(*nvm), GFP_KERNEL);
30 if (!nvm)
31 return ERR_PTR(-ENOMEM);
32
33 ret = ida_simple_get(&nvm_ida, 0, 0, GFP_KERNEL);
34 if (ret < 0) {
35 kfree(nvm);
36 return ERR_PTR(ret);
37 }
38
39 nvm->id = ret;
40 nvm->dev = dev;
41
42 return nvm;
43}
44
45/**
46 * tb_nvm_add_active() - Adds active NVMem device to NVM
47 * @nvm: NVM structure
48 * @size: Size of the active NVM in bytes
49 * @reg_read: Pointer to the function to read the NVM (passed directly to the
50 * NVMem device)
51 *
52 * Registers new active NVmem device for @nvm. The @reg_read is called
53 * directly from NVMem so it must handle possible concurrent access if
54 * needed. The first parameter passed to @reg_read is @nvm structure.
55 * Returns %0 in success and negative errno otherwise.
56 */
57int tb_nvm_add_active(struct tb_nvm *nvm, size_t size, nvmem_reg_read_t reg_read)
58{
59 struct nvmem_config config;
60 struct nvmem_device *nvmem;
61
62 memset(&config, 0, sizeof(config));
63
64 config.name = "nvm_active";
65 config.reg_read = reg_read;
66 config.read_only = true;
67 config.id = nvm->id;
68 config.stride = 4;
69 config.word_size = 4;
70 config.size = size;
71 config.dev = nvm->dev;
72 config.owner = THIS_MODULE;
73 config.priv = nvm;
74
75 nvmem = nvmem_register(&config);
76 if (IS_ERR(nvmem))
77 return PTR_ERR(nvmem);
78
79 nvm->active = nvmem;
80 return 0;
81}
82
83/**
84 * tb_nvm_write_buf() - Write data to @nvm buffer
85 * @nvm: NVM structure
86 * @offset: Offset where to write the data
87 * @val: Data buffer to write
88 * @bytes: Number of bytes to write
89 *
90 * Helper function to cache the new NVM image before it is actually
91 * written to the flash. Copies @bytes from @val to @nvm->buf starting
92 * from @offset.
93 */
94int tb_nvm_write_buf(struct tb_nvm *nvm, unsigned int offset, void *val,
95 size_t bytes)
96{
97 if (!nvm->buf) {
98 nvm->buf = vmalloc(NVM_MAX_SIZE);
99 if (!nvm->buf)
100 return -ENOMEM;
101 }
102
103 nvm->flushed = false;
104 nvm->buf_data_size = offset + bytes;
105 memcpy(nvm->buf + offset, val, bytes);
106 return 0;
107}
108
109/**
110 * tb_nvm_add_non_active() - Adds non-active NVMem device to NVM
111 * @nvm: NVM structure
112 * @size: Size of the non-active NVM in bytes
113 * @reg_write: Pointer to the function to write the NVM (passed directly
114 * to the NVMem device)
115 *
116 * Registers new non-active NVmem device for @nvm. The @reg_write is called
117 * directly from NVMem so it must handle possible concurrent access if
118 * needed. The first parameter passed to @reg_write is @nvm structure.
119 * Returns %0 in success and negative errno otherwise.
120 */
121int tb_nvm_add_non_active(struct tb_nvm *nvm, size_t size,
122 nvmem_reg_write_t reg_write)
123{
124 struct nvmem_config config;
125 struct nvmem_device *nvmem;
126
127 memset(&config, 0, sizeof(config));
128
129 config.name = "nvm_non_active";
130 config.reg_write = reg_write;
131 config.root_only = true;
132 config.id = nvm->id;
133 config.stride = 4;
134 config.word_size = 4;
135 config.size = size;
136 config.dev = nvm->dev;
137 config.owner = THIS_MODULE;
138 config.priv = nvm;
139
140 nvmem = nvmem_register(&config);
141 if (IS_ERR(nvmem))
142 return PTR_ERR(nvmem);
143
144 nvm->non_active = nvmem;
145 return 0;
146}
147
148/**
149 * tb_nvm_free() - Release NVM and its resources
150 * @nvm: NVM structure to release
151 *
152 * Releases NVM and the NVMem devices if they were registered.
153 */
154void tb_nvm_free(struct tb_nvm *nvm)
155{
156 if (nvm) {
157 if (nvm->non_active)
158 nvmem_unregister(nvm->non_active);
159 if (nvm->active)
160 nvmem_unregister(nvm->active);
161 vfree(nvm->buf);
162 ida_simple_remove(&nvm_ida, nvm->id);
163 }
164 kfree(nvm);
165}
166
167void tb_nvm_exit(void)
168{
169 ida_destroy(&nvm_ida);
170}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NVM helpers
4 *
5 * Copyright (C) 2020, Intel Corporation
6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
7 */
8
9#include <linux/idr.h>
10#include <linux/slab.h>
11#include <linux/vmalloc.h>
12
13#include "tb.h"
14
15static DEFINE_IDA(nvm_ida);
16
17/**
18 * tb_nvm_alloc() - Allocate new NVM structure
19 * @dev: Device owning the NVM
20 *
21 * Allocates new NVM structure with unique @id and returns it. In case
22 * of error returns ERR_PTR().
23 */
24struct tb_nvm *tb_nvm_alloc(struct device *dev)
25{
26 struct tb_nvm *nvm;
27 int ret;
28
29 nvm = kzalloc(sizeof(*nvm), GFP_KERNEL);
30 if (!nvm)
31 return ERR_PTR(-ENOMEM);
32
33 ret = ida_simple_get(&nvm_ida, 0, 0, GFP_KERNEL);
34 if (ret < 0) {
35 kfree(nvm);
36 return ERR_PTR(ret);
37 }
38
39 nvm->id = ret;
40 nvm->dev = dev;
41
42 return nvm;
43}
44
45/**
46 * tb_nvm_add_active() - Adds active NVMem device to NVM
47 * @nvm: NVM structure
48 * @size: Size of the active NVM in bytes
49 * @reg_read: Pointer to the function to read the NVM (passed directly to the
50 * NVMem device)
51 *
52 * Registers new active NVmem device for @nvm. The @reg_read is called
53 * directly from NVMem so it must handle possible concurrent access if
54 * needed. The first parameter passed to @reg_read is @nvm structure.
55 * Returns %0 in success and negative errno otherwise.
56 */
57int tb_nvm_add_active(struct tb_nvm *nvm, size_t size, nvmem_reg_read_t reg_read)
58{
59 struct nvmem_config config;
60 struct nvmem_device *nvmem;
61
62 memset(&config, 0, sizeof(config));
63
64 config.name = "nvm_active";
65 config.reg_read = reg_read;
66 config.read_only = true;
67 config.id = nvm->id;
68 config.stride = 4;
69 config.word_size = 4;
70 config.size = size;
71 config.dev = nvm->dev;
72 config.owner = THIS_MODULE;
73 config.priv = nvm;
74
75 nvmem = nvmem_register(&config);
76 if (IS_ERR(nvmem))
77 return PTR_ERR(nvmem);
78
79 nvm->active = nvmem;
80 return 0;
81}
82
83/**
84 * tb_nvm_write_buf() - Write data to @nvm buffer
85 * @nvm: NVM structure
86 * @offset: Offset where to write the data
87 * @val: Data buffer to write
88 * @bytes: Number of bytes to write
89 *
90 * Helper function to cache the new NVM image before it is actually
91 * written to the flash. Copies @bytes from @val to @nvm->buf starting
92 * from @offset.
93 */
94int tb_nvm_write_buf(struct tb_nvm *nvm, unsigned int offset, void *val,
95 size_t bytes)
96{
97 if (!nvm->buf) {
98 nvm->buf = vmalloc(NVM_MAX_SIZE);
99 if (!nvm->buf)
100 return -ENOMEM;
101 }
102
103 nvm->flushed = false;
104 nvm->buf_data_size = offset + bytes;
105 memcpy(nvm->buf + offset, val, bytes);
106 return 0;
107}
108
109/**
110 * tb_nvm_add_non_active() - Adds non-active NVMem device to NVM
111 * @nvm: NVM structure
112 * @size: Size of the non-active NVM in bytes
113 * @reg_write: Pointer to the function to write the NVM (passed directly
114 * to the NVMem device)
115 *
116 * Registers new non-active NVmem device for @nvm. The @reg_write is called
117 * directly from NVMem so it must handle possible concurrent access if
118 * needed. The first parameter passed to @reg_write is @nvm structure.
119 * Returns %0 in success and negative errno otherwise.
120 */
121int tb_nvm_add_non_active(struct tb_nvm *nvm, size_t size,
122 nvmem_reg_write_t reg_write)
123{
124 struct nvmem_config config;
125 struct nvmem_device *nvmem;
126
127 memset(&config, 0, sizeof(config));
128
129 config.name = "nvm_non_active";
130 config.reg_write = reg_write;
131 config.root_only = true;
132 config.id = nvm->id;
133 config.stride = 4;
134 config.word_size = 4;
135 config.size = size;
136 config.dev = nvm->dev;
137 config.owner = THIS_MODULE;
138 config.priv = nvm;
139
140 nvmem = nvmem_register(&config);
141 if (IS_ERR(nvmem))
142 return PTR_ERR(nvmem);
143
144 nvm->non_active = nvmem;
145 return 0;
146}
147
148/**
149 * tb_nvm_free() - Release NVM and its resources
150 * @nvm: NVM structure to release
151 *
152 * Releases NVM and the NVMem devices if they were registered.
153 */
154void tb_nvm_free(struct tb_nvm *nvm)
155{
156 if (nvm) {
157 if (nvm->non_active)
158 nvmem_unregister(nvm->non_active);
159 if (nvm->active)
160 nvmem_unregister(nvm->active);
161 vfree(nvm->buf);
162 ida_simple_remove(&nvm_ida, nvm->id);
163 }
164 kfree(nvm);
165}
166
167/**
168 * tb_nvm_read_data() - Read data from NVM
169 * @address: Start address on the flash
170 * @buf: Buffer where the read data is copied
171 * @size: Size of the buffer in bytes
172 * @retries: Number of retries if block read fails
173 * @read_block: Function that reads block from the flash
174 * @read_block_data: Data passsed to @read_block
175 *
176 * This is a generic function that reads data from NVM or NVM like
177 * device.
178 *
179 * Returns %0 on success and negative errno otherwise.
180 */
181int tb_nvm_read_data(unsigned int address, void *buf, size_t size,
182 unsigned int retries, read_block_fn read_block,
183 void *read_block_data)
184{
185 do {
186 unsigned int dwaddress, dwords, offset;
187 u8 data[NVM_DATA_DWORDS * 4];
188 size_t nbytes;
189 int ret;
190
191 offset = address & 3;
192 nbytes = min_t(size_t, size + offset, NVM_DATA_DWORDS * 4);
193
194 dwaddress = address / 4;
195 dwords = ALIGN(nbytes, 4) / 4;
196
197 ret = read_block(read_block_data, dwaddress, data, dwords);
198 if (ret) {
199 if (ret != -ENODEV && retries--)
200 continue;
201 return ret;
202 }
203
204 nbytes -= offset;
205 memcpy(buf, data + offset, nbytes);
206
207 size -= nbytes;
208 address += nbytes;
209 buf += nbytes;
210 } while (size > 0);
211
212 return 0;
213}
214
215/**
216 * tb_nvm_write_data() - Write data to NVM
217 * @address: Start address on the flash
218 * @buf: Buffer where the data is copied from
219 * @size: Size of the buffer in bytes
220 * @retries: Number of retries if the block write fails
221 * @write_block: Function that writes block to the flash
222 * @write_block_data: Data passwd to @write_block
223 *
224 * This is generic function that writes data to NVM or NVM like device.
225 *
226 * Returns %0 on success and negative errno otherwise.
227 */
228int tb_nvm_write_data(unsigned int address, const void *buf, size_t size,
229 unsigned int retries, write_block_fn write_block,
230 void *write_block_data)
231{
232 do {
233 unsigned int offset, dwaddress;
234 u8 data[NVM_DATA_DWORDS * 4];
235 size_t nbytes;
236 int ret;
237
238 offset = address & 3;
239 nbytes = min_t(u32, size + offset, NVM_DATA_DWORDS * 4);
240
241 memcpy(data + offset, buf, nbytes);
242
243 dwaddress = address / 4;
244 ret = write_block(write_block_data, dwaddress, data, nbytes / 4);
245 if (ret) {
246 if (ret == -ETIMEDOUT) {
247 if (retries--)
248 continue;
249 ret = -EIO;
250 }
251 return ret;
252 }
253
254 size -= nbytes;
255 address += nbytes;
256 buf += nbytes;
257 } while (size > 0);
258
259 return 0;
260}
261
262void tb_nvm_exit(void)
263{
264 ida_destroy(&nvm_ida);
265}