1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ST's Remote Processor Control Driver
4 *
5 * Copyright (C) 2015 STMicroelectronics - All Rights Reserved
6 *
7 * Author: Ludovic Barre <ludovic.barre@st.com>
8 */
9
10 #include <linux/clk.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/err.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/mailbox_client.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_reserved_mem.h>
20 #include <linux/platform_device.h>
21 #include <linux/property.h>
22 #include <linux/regmap.h>
23 #include <linux/remoteproc.h>
24 #include <linux/reset.h>
25
26 #include "remoteproc_internal.h"
27
28 #define ST_RPROC_VQ0 0
29 #define ST_RPROC_VQ1 1
30 #define ST_RPROC_MAX_VRING 2
31
32 #define MBOX_RX 0
33 #define MBOX_TX 1
34 #define MBOX_MAX 2
35
36 struct st_rproc_config {
37 bool sw_reset;
38 bool pwr_reset;
39 unsigned long bootaddr_mask;
40 };
41
42 struct st_rproc {
43 struct st_rproc_config *config;
44 struct reset_control *sw_reset;
45 struct reset_control *pwr_reset;
46 struct clk *clk;
47 u32 clk_rate;
48 struct regmap *boot_base;
49 u32 boot_offset;
50 struct mbox_chan *mbox_chan[ST_RPROC_MAX_VRING * MBOX_MAX];
51 struct mbox_client mbox_client_vq0;
52 struct mbox_client mbox_client_vq1;
53 };
54
st_rproc_mbox_callback(struct device * dev,u32 msg)55 static void st_rproc_mbox_callback(struct device *dev, u32 msg)
56 {
57 struct rproc *rproc = dev_get_drvdata(dev);
58
59 if (rproc_vq_interrupt(rproc, msg) == IRQ_NONE)
60 dev_dbg(dev, "no message was found in vqid %d\n", msg);
61 }
62
63 static
st_rproc_mbox_callback_vq0(struct mbox_client * mbox_client,void * data)64 void st_rproc_mbox_callback_vq0(struct mbox_client *mbox_client, void *data)
65 {
66 st_rproc_mbox_callback(mbox_client->dev, 0);
67 }
68
69 static
st_rproc_mbox_callback_vq1(struct mbox_client * mbox_client,void * data)70 void st_rproc_mbox_callback_vq1(struct mbox_client *mbox_client, void *data)
71 {
72 st_rproc_mbox_callback(mbox_client->dev, 1);
73 }
74
st_rproc_kick(struct rproc * rproc,int vqid)75 static void st_rproc_kick(struct rproc *rproc, int vqid)
76 {
77 struct st_rproc *ddata = rproc->priv;
78 struct device *dev = rproc->dev.parent;
79 int ret;
80
81 /* send the index of the triggered virtqueue in the mailbox payload */
82 if (WARN_ON(vqid >= ST_RPROC_MAX_VRING))
83 return;
84
85 ret = mbox_send_message(ddata->mbox_chan[vqid * MBOX_MAX + MBOX_TX],
86 (void *)&vqid);
87 if (ret < 0)
88 dev_err(dev, "failed to send message via mbox: %d\n", ret);
89 }
90
st_rproc_mem_alloc(struct rproc * rproc,struct rproc_mem_entry * mem)91 static int st_rproc_mem_alloc(struct rproc *rproc,
92 struct rproc_mem_entry *mem)
93 {
94 struct device *dev = rproc->dev.parent;
95 void *va;
96
97 va = ioremap_wc(mem->dma, mem->len);
98 if (!va) {
99 dev_err(dev, "Unable to map memory region: %pa+%zx\n",
100 &mem->dma, mem->len);
101 return -ENOMEM;
102 }
103
104 /* Update memory entry va */
105 mem->va = va;
106
107 return 0;
108 }
109
st_rproc_mem_release(struct rproc * rproc,struct rproc_mem_entry * mem)110 static int st_rproc_mem_release(struct rproc *rproc,
111 struct rproc_mem_entry *mem)
112 {
113 iounmap(mem->va);
114
115 return 0;
116 }
117
st_rproc_parse_fw(struct rproc * rproc,const struct firmware * fw)118 static int st_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
119 {
120 struct device *dev = rproc->dev.parent;
121 struct device_node *np = dev->of_node;
122 struct rproc_mem_entry *mem;
123 int entries;
124
125 entries = of_reserved_mem_region_count(np);
126
127 for (int index = 0; index < entries; index++) {
128 struct resource res;
129 int ret;
130
131 ret = of_reserved_mem_region_to_resource(np, index, &res);
132 if (ret)
133 return ret;
134
135 /* No need to map vdev buffer */
136 if (!strstarts(res.name, "vdev0buffer")) {
137 /* Register memory region */
138 mem = rproc_mem_entry_init(dev, NULL,
139 (dma_addr_t)res.start,
140 resource_size(&res), res.start,
141 st_rproc_mem_alloc,
142 st_rproc_mem_release,
143 "%.*s",
144 strchrnul(res.name, '@') - res.name,
145 res.name);
146 } else {
147 /* Register reserved memory for vdev buffer allocation */
148 mem = rproc_of_resm_mem_entry_init(dev, index,
149 resource_size(&res),
150 res.start,
151 "vdev0buffer");
152 }
153
154 if (!mem)
155 return -ENOMEM;
156
157 rproc_add_carveout(rproc, mem);
158 }
159
160 return rproc_elf_load_rsc_table(rproc, fw);
161 }
162
st_rproc_start(struct rproc * rproc)163 static int st_rproc_start(struct rproc *rproc)
164 {
165 struct st_rproc *ddata = rproc->priv;
166 int err;
167
168 regmap_update_bits(ddata->boot_base, ddata->boot_offset,
169 ddata->config->bootaddr_mask, rproc->bootaddr);
170
171 err = clk_enable(ddata->clk);
172 if (err) {
173 dev_err(&rproc->dev, "Failed to enable clock\n");
174 return err;
175 }
176
177 if (ddata->config->sw_reset) {
178 err = reset_control_deassert(ddata->sw_reset);
179 if (err) {
180 dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
181 goto sw_reset_fail;
182 }
183 }
184
185 if (ddata->config->pwr_reset) {
186 err = reset_control_deassert(ddata->pwr_reset);
187 if (err) {
188 dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
189 goto pwr_reset_fail;
190 }
191 }
192
193 dev_info(&rproc->dev, "Started from 0x%llx\n", rproc->bootaddr);
194
195 return 0;
196
197
198 pwr_reset_fail:
199 if (ddata->config->pwr_reset)
200 reset_control_assert(ddata->sw_reset);
201 sw_reset_fail:
202 clk_disable(ddata->clk);
203
204 return err;
205 }
206
st_rproc_stop(struct rproc * rproc)207 static int st_rproc_stop(struct rproc *rproc)
208 {
209 struct st_rproc *ddata = rproc->priv;
210 int sw_err = 0, pwr_err = 0;
211
212 if (ddata->config->sw_reset) {
213 sw_err = reset_control_assert(ddata->sw_reset);
214 if (sw_err)
215 dev_err(&rproc->dev, "Failed to assert S/W Reset\n");
216 }
217
218 if (ddata->config->pwr_reset) {
219 pwr_err = reset_control_assert(ddata->pwr_reset);
220 if (pwr_err)
221 dev_err(&rproc->dev, "Failed to assert Power Reset\n");
222 }
223
224 clk_disable(ddata->clk);
225
226 return sw_err ?: pwr_err;
227 }
228
229 static const struct rproc_ops st_rproc_ops = {
230 .kick = st_rproc_kick,
231 .start = st_rproc_start,
232 .stop = st_rproc_stop,
233 .parse_fw = st_rproc_parse_fw,
234 .load = rproc_elf_load_segments,
235 .find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table,
236 .sanity_check = rproc_elf_sanity_check,
237 .get_boot_addr = rproc_elf_get_boot_addr,
238 };
239
240 /*
241 * Fetch state of the processor: 0 is off, 1 is on.
242 */
st_rproc_state(struct platform_device * pdev)243 static int st_rproc_state(struct platform_device *pdev)
244 {
245 struct rproc *rproc = platform_get_drvdata(pdev);
246 struct st_rproc *ddata = rproc->priv;
247 int reset_sw = 0, reset_pwr = 0;
248
249 if (ddata->config->sw_reset)
250 reset_sw = reset_control_status(ddata->sw_reset);
251
252 if (ddata->config->pwr_reset)
253 reset_pwr = reset_control_status(ddata->pwr_reset);
254
255 if (reset_sw < 0 || reset_pwr < 0)
256 return -EINVAL;
257
258 return !reset_sw && !reset_pwr;
259 }
260
261 static const struct st_rproc_config st40_rproc_cfg = {
262 .sw_reset = true,
263 .pwr_reset = true,
264 .bootaddr_mask = GENMASK(28, 1),
265 };
266
267 static const struct st_rproc_config st231_rproc_cfg = {
268 .sw_reset = true,
269 .pwr_reset = false,
270 .bootaddr_mask = GENMASK(31, 6),
271 };
272
273 static const struct of_device_id st_rproc_match[] = {
274 { .compatible = "st,st40-rproc", .data = &st40_rproc_cfg },
275 { .compatible = "st,st231-rproc", .data = &st231_rproc_cfg },
276 {},
277 };
278 MODULE_DEVICE_TABLE(of, st_rproc_match);
279
st_rproc_parse_dt(struct platform_device * pdev)280 static int st_rproc_parse_dt(struct platform_device *pdev)
281 {
282 struct device *dev = &pdev->dev;
283 struct rproc *rproc = platform_get_drvdata(pdev);
284 struct st_rproc *ddata = rproc->priv;
285 struct device_node *np = dev->of_node;
286 int err;
287
288 if (ddata->config->sw_reset) {
289 ddata->sw_reset = devm_reset_control_get_exclusive(dev,
290 "sw_reset");
291 if (IS_ERR(ddata->sw_reset))
292 return dev_err_probe(dev, PTR_ERR(ddata->sw_reset),
293 "Failed to get S/W Reset\n");
294 }
295
296 if (ddata->config->pwr_reset) {
297 ddata->pwr_reset = devm_reset_control_get_exclusive(dev,
298 "pwr_reset");
299 if (IS_ERR(ddata->pwr_reset))
300 return dev_err_probe(dev, PTR_ERR(ddata->pwr_reset),
301 "Failed to get Power Reset\n");
302 }
303
304 ddata->clk = devm_clk_get(dev, NULL);
305 if (IS_ERR(ddata->clk))
306 return dev_err_probe(dev, PTR_ERR(ddata->clk),
307 "Failed to get clock\n");
308
309 err = of_property_read_u32(np, "clock-frequency", &ddata->clk_rate);
310 if (err) {
311 dev_err(dev, "failed to get clock frequency\n");
312 return err;
313 }
314
315 ddata->boot_base = syscon_regmap_lookup_by_phandle_args(np, "st,syscfg",
316 1, &ddata->boot_offset);
317 if (IS_ERR(ddata->boot_base))
318 return dev_err_probe(dev, PTR_ERR(ddata->boot_base),
319 "Boot base not found\n");
320
321 err = clk_prepare(ddata->clk);
322 if (err)
323 dev_err(dev, "failed to get clock\n");
324
325 return err;
326 }
327
st_rproc_probe(struct platform_device * pdev)328 static int st_rproc_probe(struct platform_device *pdev)
329 {
330 struct device *dev = &pdev->dev;
331 struct st_rproc *ddata;
332 struct device_node *np = dev->of_node;
333 struct rproc *rproc;
334 struct mbox_chan *chan;
335 int enabled;
336 int ret, i;
337
338 rproc = devm_rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
339 if (!rproc)
340 return -ENOMEM;
341
342 rproc->has_iommu = false;
343 ddata = rproc->priv;
344 ddata->config = (struct st_rproc_config *)device_get_match_data(dev);
345 if (!ddata->config)
346 return -ENODEV;
347
348 platform_set_drvdata(pdev, rproc);
349
350 ret = st_rproc_parse_dt(pdev);
351 if (ret)
352 return ret;
353
354 enabled = st_rproc_state(pdev);
355 if (enabled < 0) {
356 ret = enabled;
357 goto free_clk;
358 }
359
360 if (enabled) {
361 atomic_inc(&rproc->power);
362 rproc->state = RPROC_RUNNING;
363 } else {
364 clk_set_rate(ddata->clk, ddata->clk_rate);
365 }
366
367 if (of_property_present(np, "mbox-names")) {
368 ddata->mbox_client_vq0.dev = dev;
369 ddata->mbox_client_vq0.tx_done = NULL;
370 ddata->mbox_client_vq0.tx_block = false;
371 ddata->mbox_client_vq0.knows_txdone = false;
372 ddata->mbox_client_vq0.rx_callback = st_rproc_mbox_callback_vq0;
373
374 ddata->mbox_client_vq1.dev = dev;
375 ddata->mbox_client_vq1.tx_done = NULL;
376 ddata->mbox_client_vq1.tx_block = false;
377 ddata->mbox_client_vq1.knows_txdone = false;
378 ddata->mbox_client_vq1.rx_callback = st_rproc_mbox_callback_vq1;
379
380 /*
381 * To control a co-processor without IPC mechanism.
382 * This driver can be used without mbox and rpmsg.
383 */
384 chan = mbox_request_channel_byname(&ddata->mbox_client_vq0, "vq0_rx");
385 if (IS_ERR(chan)) {
386 ret = dev_err_probe(&rproc->dev, PTR_ERR(chan),
387 "failed to request mbox chan 0\n");
388 goto free_clk;
389 }
390 ddata->mbox_chan[ST_RPROC_VQ0 * MBOX_MAX + MBOX_RX] = chan;
391
392 chan = mbox_request_channel_byname(&ddata->mbox_client_vq0, "vq0_tx");
393 if (IS_ERR(chan)) {
394 ret = dev_err_probe(&rproc->dev, PTR_ERR(chan),
395 "failed to request mbox chan 0\n");
396 goto free_mbox;
397 }
398 ddata->mbox_chan[ST_RPROC_VQ0 * MBOX_MAX + MBOX_TX] = chan;
399
400 chan = mbox_request_channel_byname(&ddata->mbox_client_vq1, "vq1_rx");
401 if (IS_ERR(chan)) {
402 ret = dev_err_probe(&rproc->dev, PTR_ERR(chan),
403 "failed to request mbox chan 1\n");
404 goto free_mbox;
405 }
406 ddata->mbox_chan[ST_RPROC_VQ1 * MBOX_MAX + MBOX_RX] = chan;
407
408 chan = mbox_request_channel_byname(&ddata->mbox_client_vq1, "vq1_tx");
409 if (IS_ERR(chan)) {
410 ret = dev_err_probe(&rproc->dev, PTR_ERR(chan),
411 "failed to request mbox chan 1\n");
412 goto free_mbox;
413 }
414 ddata->mbox_chan[ST_RPROC_VQ1 * MBOX_MAX + MBOX_TX] = chan;
415 }
416
417 ret = rproc_add(rproc);
418 if (ret)
419 goto free_mbox;
420
421 return 0;
422
423 free_mbox:
424 for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
425 mbox_free_channel(ddata->mbox_chan[i]);
426 free_clk:
427 clk_unprepare(ddata->clk);
428
429 return ret;
430 }
431
st_rproc_remove(struct platform_device * pdev)432 static void st_rproc_remove(struct platform_device *pdev)
433 {
434 struct rproc *rproc = platform_get_drvdata(pdev);
435 struct st_rproc *ddata = rproc->priv;
436 int i;
437
438 rproc_del(rproc);
439
440 clk_disable_unprepare(ddata->clk);
441
442 for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
443 mbox_free_channel(ddata->mbox_chan[i]);
444 }
445
446 static struct platform_driver st_rproc_driver = {
447 .probe = st_rproc_probe,
448 .remove = st_rproc_remove,
449 .driver = {
450 .name = "st-rproc",
451 .of_match_table = of_match_ptr(st_rproc_match),
452 },
453 };
454 module_platform_driver(st_rproc_driver);
455
456 MODULE_DESCRIPTION("ST Remote Processor Control Driver");
457 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
458 MODULE_LICENSE("GPL v2");
459