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8#include <linux/clk.h>
9#include <linux/delay.h>
10#include <linux/genalloc.h>
11#include <linux/io.h>
12#include <linux/list_sort.h>
13#include <linux/of_address.h>
14#include <linux/of_device.h>
15#include <linux/platform_device.h>
16#include <linux/regmap.h>
17#include <linux/slab.h>
18#include <linux/mfd/syscon.h>
19#include <soc/at91/atmel-secumod.h>
20
21#include "sram.h"
22
23#define SRAM_GRANULARITY 32
24
25static ssize_t sram_read(struct file *filp, struct kobject *kobj,
26 struct bin_attribute *attr,
27 char *buf, loff_t pos, size_t count)
28{
29 struct sram_partition *part;
30
31 part = container_of(attr, struct sram_partition, battr);
32
33 mutex_lock(&part->lock);
34 memcpy_fromio(buf, part->base + pos, count);
35 mutex_unlock(&part->lock);
36
37 return count;
38}
39
40static ssize_t sram_write(struct file *filp, struct kobject *kobj,
41 struct bin_attribute *attr,
42 char *buf, loff_t pos, size_t count)
43{
44 struct sram_partition *part;
45
46 part = container_of(attr, struct sram_partition, battr);
47
48 mutex_lock(&part->lock);
49 memcpy_toio(part->base + pos, buf, count);
50 mutex_unlock(&part->lock);
51
52 return count;
53}
54
55static int sram_add_pool(struct sram_dev *sram, struct sram_reserve *block,
56 phys_addr_t start, struct sram_partition *part)
57{
58 int ret;
59
60 part->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY),
61 NUMA_NO_NODE, block->label);
62 if (IS_ERR(part->pool))
63 return PTR_ERR(part->pool);
64
65 ret = gen_pool_add_virt(part->pool, (unsigned long)part->base, start,
66 block->size, NUMA_NO_NODE);
67 if (ret < 0) {
68 dev_err(sram->dev, "failed to register subpool: %d\n", ret);
69 return ret;
70 }
71
72 return 0;
73}
74
75static int sram_add_export(struct sram_dev *sram, struct sram_reserve *block,
76 phys_addr_t start, struct sram_partition *part)
77{
78 sysfs_bin_attr_init(&part->battr);
79 part->battr.attr.name = devm_kasprintf(sram->dev, GFP_KERNEL,
80 "%llx.sram",
81 (unsigned long long)start);
82 if (!part->battr.attr.name)
83 return -ENOMEM;
84
85 part->battr.attr.mode = S_IRUSR | S_IWUSR;
86 part->battr.read = sram_read;
87 part->battr.write = sram_write;
88 part->battr.size = block->size;
89
90 return device_create_bin_file(sram->dev, &part->battr);
91}
92
93static int sram_add_partition(struct sram_dev *sram, struct sram_reserve *block,
94 phys_addr_t start)
95{
96 int ret;
97 struct sram_partition *part = &sram->partition[sram->partitions];
98
99 mutex_init(&part->lock);
100
101 if (sram->config && sram->config->map_only_reserved) {
102 void __iomem *virt_base;
103
104 if (sram->no_memory_wc)
105 virt_base = devm_ioremap_resource(sram->dev, &block->res);
106 else
107 virt_base = devm_ioremap_resource_wc(sram->dev, &block->res);
108
109 if (IS_ERR(virt_base)) {
110 dev_err(sram->dev, "could not map SRAM at %pr\n", &block->res);
111 return PTR_ERR(virt_base);
112 }
113
114 part->base = virt_base;
115 } else {
116 part->base = sram->virt_base + block->start;
117 }
118
119 if (block->pool) {
120 ret = sram_add_pool(sram, block, start, part);
121 if (ret)
122 return ret;
123 }
124 if (block->export) {
125 ret = sram_add_export(sram, block, start, part);
126 if (ret)
127 return ret;
128 }
129 if (block->protect_exec) {
130 ret = sram_check_protect_exec(sram, block, part);
131 if (ret)
132 return ret;
133
134 ret = sram_add_pool(sram, block, start, part);
135 if (ret)
136 return ret;
137
138 sram_add_protect_exec(part);
139 }
140
141 sram->partitions++;
142
143 return 0;
144}
145
146static void sram_free_partitions(struct sram_dev *sram)
147{
148 struct sram_partition *part;
149
150 if (!sram->partitions)
151 return;
152
153 part = &sram->partition[sram->partitions - 1];
154 for (; sram->partitions; sram->partitions--, part--) {
155 if (part->battr.size)
156 device_remove_bin_file(sram->dev, &part->battr);
157
158 if (part->pool &&
159 gen_pool_avail(part->pool) < gen_pool_size(part->pool))
160 dev_err(sram->dev, "removed pool while SRAM allocated\n");
161 }
162}
163
164static int sram_reserve_cmp(void *priv, const struct list_head *a,
165 const struct list_head *b)
166{
167 struct sram_reserve *ra = list_entry(a, struct sram_reserve, list);
168 struct sram_reserve *rb = list_entry(b, struct sram_reserve, list);
169
170 return ra->start - rb->start;
171}
172
173static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
174{
175 struct device_node *np = sram->dev->of_node, *child;
176 unsigned long size, cur_start, cur_size;
177 struct sram_reserve *rblocks, *block;
178 struct list_head reserve_list;
179 unsigned int nblocks, exports = 0;
180 const char *label;
181 int ret = 0;
182
183 INIT_LIST_HEAD(&reserve_list);
184
185 size = resource_size(res);
186
187
188
189
190
191 nblocks = (np) ? of_get_available_child_count(np) + 1 : 1;
192 rblocks = kcalloc(nblocks, sizeof(*rblocks), GFP_KERNEL);
193 if (!rblocks)
194 return -ENOMEM;
195
196 block = &rblocks[0];
197 for_each_available_child_of_node(np, child) {
198 struct resource child_res;
199
200 ret = of_address_to_resource(child, 0, &child_res);
201 if (ret < 0) {
202 dev_err(sram->dev,
203 "could not get address for node %pOF\n",
204 child);
205 goto err_chunks;
206 }
207
208 if (child_res.start < res->start || child_res.end > res->end) {
209 dev_err(sram->dev,
210 "reserved block %pOF outside the sram area\n",
211 child);
212 ret = -EINVAL;
213 goto err_chunks;
214 }
215
216 block->start = child_res.start - res->start;
217 block->size = resource_size(&child_res);
218 block->res = child_res;
219 list_add_tail(&block->list, &reserve_list);
220
221 if (of_find_property(child, "export", NULL))
222 block->export = true;
223
224 if (of_find_property(child, "pool", NULL))
225 block->pool = true;
226
227 if (of_find_property(child, "protect-exec", NULL))
228 block->protect_exec = true;
229
230 if ((block->export || block->pool || block->protect_exec) &&
231 block->size) {
232 exports++;
233
234 label = NULL;
235 ret = of_property_read_string(child, "label", &label);
236 if (ret && ret != -EINVAL) {
237 dev_err(sram->dev,
238 "%pOF has invalid label name\n",
239 child);
240 goto err_chunks;
241 }
242 if (!label)
243 label = child->name;
244
245 block->label = devm_kstrdup(sram->dev,
246 label, GFP_KERNEL);
247 if (!block->label) {
248 ret = -ENOMEM;
249 goto err_chunks;
250 }
251
252 dev_dbg(sram->dev, "found %sblock '%s' 0x%x-0x%x\n",
253 block->export ? "exported " : "", block->label,
254 block->start, block->start + block->size);
255 } else {
256 dev_dbg(sram->dev, "found reserved block 0x%x-0x%x\n",
257 block->start, block->start + block->size);
258 }
259
260 block++;
261 }
262 child = NULL;
263
264
265 rblocks[nblocks - 1].start = size;
266 rblocks[nblocks - 1].size = 0;
267 list_add_tail(&rblocks[nblocks - 1].list, &reserve_list);
268
269 list_sort(NULL, &reserve_list, sram_reserve_cmp);
270
271 if (exports) {
272 sram->partition = devm_kcalloc(sram->dev,
273 exports, sizeof(*sram->partition),
274 GFP_KERNEL);
275 if (!sram->partition) {
276 ret = -ENOMEM;
277 goto err_chunks;
278 }
279 }
280
281 cur_start = 0;
282 list_for_each_entry(block, &reserve_list, list) {
283
284 if (block->start < cur_start) {
285 dev_err(sram->dev,
286 "block at 0x%x starts after current offset 0x%lx\n",
287 block->start, cur_start);
288 ret = -EINVAL;
289 sram_free_partitions(sram);
290 goto err_chunks;
291 }
292
293 if ((block->export || block->pool || block->protect_exec) &&
294 block->size) {
295 ret = sram_add_partition(sram, block,
296 res->start + block->start);
297 if (ret) {
298 sram_free_partitions(sram);
299 goto err_chunks;
300 }
301 }
302
303
304 if (block->start == cur_start) {
305 cur_start = block->start + block->size;
306 continue;
307 }
308
309
310
311
312
313
314 cur_size = block->start - cur_start;
315
316 if (sram->pool) {
317 dev_dbg(sram->dev, "adding chunk 0x%lx-0x%lx\n",
318 cur_start, cur_start + cur_size);
319
320 ret = gen_pool_add_virt(sram->pool,
321 (unsigned long)sram->virt_base + cur_start,
322 res->start + cur_start, cur_size, -1);
323 if (ret < 0) {
324 sram_free_partitions(sram);
325 goto err_chunks;
326 }
327 }
328
329
330 cur_start = block->start + block->size;
331 }
332
333err_chunks:
334 of_node_put(child);
335 kfree(rblocks);
336
337 return ret;
338}
339
340static int atmel_securam_wait(void)
341{
342 struct regmap *regmap;
343 u32 val;
344
345 regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-secumod");
346 if (IS_ERR(regmap))
347 return -ENODEV;
348
349 return regmap_read_poll_timeout(regmap, AT91_SECUMOD_RAMRDY, val,
350 val & AT91_SECUMOD_RAMRDY_READY,
351 10000, 500000);
352}
353
354static const struct sram_config atmel_securam_config = {
355 .init = atmel_securam_wait,
356};
357
358
359
360
361
362
363
364
365static const struct sram_config tegra_sysram_config = {
366 .map_only_reserved = true,
367};
368
369static const struct of_device_id sram_dt_ids[] = {
370 { .compatible = "mmio-sram" },
371 { .compatible = "atmel,sama5d2-securam", .data = &atmel_securam_config },
372 { .compatible = "nvidia,tegra186-sysram", .data = &tegra_sysram_config },
373 { .compatible = "nvidia,tegra194-sysram", .data = &tegra_sysram_config },
374 {}
375};
376
377static int sram_probe(struct platform_device *pdev)
378{
379 const struct sram_config *config;
380 struct sram_dev *sram;
381 int ret;
382 struct resource *res;
383
384 config = of_device_get_match_data(&pdev->dev);
385
386 sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL);
387 if (!sram)
388 return -ENOMEM;
389
390 sram->dev = &pdev->dev;
391 sram->no_memory_wc = of_property_read_bool(pdev->dev.of_node, "no-memory-wc");
392 sram->config = config;
393
394 if (!config || !config->map_only_reserved) {
395 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
396 if (sram->no_memory_wc)
397 sram->virt_base = devm_ioremap_resource(&pdev->dev, res);
398 else
399 sram->virt_base = devm_ioremap_resource_wc(&pdev->dev, res);
400 if (IS_ERR(sram->virt_base)) {
401 dev_err(&pdev->dev, "could not map SRAM registers\n");
402 return PTR_ERR(sram->virt_base);
403 }
404
405 sram->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY),
406 NUMA_NO_NODE, NULL);
407 if (IS_ERR(sram->pool))
408 return PTR_ERR(sram->pool);
409 }
410
411 sram->clk = devm_clk_get(sram->dev, NULL);
412 if (IS_ERR(sram->clk))
413 sram->clk = NULL;
414 else
415 clk_prepare_enable(sram->clk);
416
417 ret = sram_reserve_regions(sram,
418 platform_get_resource(pdev, IORESOURCE_MEM, 0));
419 if (ret)
420 goto err_disable_clk;
421
422 platform_set_drvdata(pdev, sram);
423
424 if (config && config->init) {
425 ret = config->init();
426 if (ret)
427 goto err_free_partitions;
428 }
429
430 if (sram->pool)
431 dev_dbg(sram->dev, "SRAM pool: %zu KiB @ 0x%p\n",
432 gen_pool_size(sram->pool) / 1024, sram->virt_base);
433
434 return 0;
435
436err_free_partitions:
437 sram_free_partitions(sram);
438err_disable_clk:
439 if (sram->clk)
440 clk_disable_unprepare(sram->clk);
441
442 return ret;
443}
444
445static int sram_remove(struct platform_device *pdev)
446{
447 struct sram_dev *sram = platform_get_drvdata(pdev);
448
449 sram_free_partitions(sram);
450
451 if (sram->pool && gen_pool_avail(sram->pool) < gen_pool_size(sram->pool))
452 dev_err(sram->dev, "removed while SRAM allocated\n");
453
454 if (sram->clk)
455 clk_disable_unprepare(sram->clk);
456
457 return 0;
458}
459
460static struct platform_driver sram_driver = {
461 .driver = {
462 .name = "sram",
463 .of_match_table = sram_dt_ids,
464 },
465 .probe = sram_probe,
466 .remove = sram_remove,
467};
468
469static int __init sram_init(void)
470{
471 return platform_driver_register(&sram_driver);
472}
473
474postcore_initcall(sram_init);
475
