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
36struct st_rproc_config {
37	bool			sw_reset;
38	bool			pwr_reset;
39	unsigned long		bootaddr_mask;
40};
41
42struct 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
55static 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
63static
64void st_rproc_mbox_callback_vq0(struct mbox_client *mbox_client, void *data)
65{
66	st_rproc_mbox_callback(mbox_client->dev, 0);
67}
68
69static
70void st_rproc_mbox_callback_vq1(struct mbox_client *mbox_client, void *data)
71{
72	st_rproc_mbox_callback(mbox_client->dev, 1);
73}
74
75static 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
91static 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
110static 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
118static 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	struct reserved_mem *rmem;
124	struct of_phandle_iterator it;
125	int index = 0;
126
127	of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
128	while (of_phandle_iterator_next(&it) == 0) {
129		rmem = of_reserved_mem_lookup(it.node);
130		if (!rmem) {
131			of_node_put(it.node);
132			dev_err(dev, "unable to acquire memory-region\n");
133			return -EINVAL;
134		}
135
136		/*  No need to map vdev buffer */
137		if (strcmp(it.node->name, "vdev0buffer")) {
138			/* Register memory region */
139			mem = rproc_mem_entry_init(dev, NULL,
140						   (dma_addr_t)rmem->base,
141						   rmem->size, rmem->base,
142						   st_rproc_mem_alloc,
143						   st_rproc_mem_release,
144						   it.node->name);
145		} else {
146			/* Register reserved memory for vdev buffer allocation */
147			mem = rproc_of_resm_mem_entry_init(dev, index,
148							   rmem->size,
149							   rmem->base,
150							   it.node->name);
151		}
152
153		if (!mem) {
154			of_node_put(it.node);
155			return -ENOMEM;
156		}
157
158		rproc_add_carveout(rproc, mem);
159		index++;
160	}
161
162	return rproc_elf_load_rsc_table(rproc, fw);
163}
164
165static int st_rproc_start(struct rproc *rproc)
166{
167	struct st_rproc *ddata = rproc->priv;
168	int err;
169
170	regmap_update_bits(ddata->boot_base, ddata->boot_offset,
171			   ddata->config->bootaddr_mask, rproc->bootaddr);
172
173	err = clk_enable(ddata->clk);
174	if (err) {
175		dev_err(&rproc->dev, "Failed to enable clock\n");
176		return err;
177	}
178
179	if (ddata->config->sw_reset) {
180		err = reset_control_deassert(ddata->sw_reset);
181		if (err) {
182			dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
183			goto sw_reset_fail;
184		}
185	}
186
187	if (ddata->config->pwr_reset) {
188		err = reset_control_deassert(ddata->pwr_reset);
189		if (err) {
190			dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
191			goto pwr_reset_fail;
192		}
193	}
194
195	dev_info(&rproc->dev, "Started from 0x%llx\n", rproc->bootaddr);
196
197	return 0;
198
199
200pwr_reset_fail:
201	if (ddata->config->pwr_reset)
202		reset_control_assert(ddata->sw_reset);
203sw_reset_fail:
204	clk_disable(ddata->clk);
205
206	return err;
207}
208
209static int st_rproc_stop(struct rproc *rproc)
210{
211	struct st_rproc *ddata = rproc->priv;
212	int sw_err = 0, pwr_err = 0;
213
214	if (ddata->config->sw_reset) {
215		sw_err = reset_control_assert(ddata->sw_reset);
216		if (sw_err)
217			dev_err(&rproc->dev, "Failed to assert S/W Reset\n");
218	}
219
220	if (ddata->config->pwr_reset) {
221		pwr_err = reset_control_assert(ddata->pwr_reset);
222		if (pwr_err)
223			dev_err(&rproc->dev, "Failed to assert Power Reset\n");
224	}
225
226	clk_disable(ddata->clk);
227
228	return sw_err ?: pwr_err;
229}
230
231static const struct rproc_ops st_rproc_ops = {
232	.kick			= st_rproc_kick,
233	.start			= st_rproc_start,
234	.stop			= st_rproc_stop,
235	.parse_fw		= st_rproc_parse_fw,
236	.load			= rproc_elf_load_segments,
237	.find_loaded_rsc_table	= rproc_elf_find_loaded_rsc_table,
238	.sanity_check		= rproc_elf_sanity_check,
239	.get_boot_addr		= rproc_elf_get_boot_addr,
240};
241
242/*
243 * Fetch state of the processor: 0 is off, 1 is on.
244 */
245static int st_rproc_state(struct platform_device *pdev)
246{
247	struct rproc *rproc = platform_get_drvdata(pdev);
248	struct st_rproc *ddata = rproc->priv;
249	int reset_sw = 0, reset_pwr = 0;
250
251	if (ddata->config->sw_reset)
252		reset_sw = reset_control_status(ddata->sw_reset);
253
254	if (ddata->config->pwr_reset)
255		reset_pwr = reset_control_status(ddata->pwr_reset);
256
257	if (reset_sw < 0 || reset_pwr < 0)
258		return -EINVAL;
259
260	return !reset_sw && !reset_pwr;
261}
262
263static const struct st_rproc_config st40_rproc_cfg = {
264	.sw_reset = true,
265	.pwr_reset = true,
266	.bootaddr_mask = GENMASK(28, 1),
267};
268
269static const struct st_rproc_config st231_rproc_cfg = {
270	.sw_reset = true,
271	.pwr_reset = false,
272	.bootaddr_mask = GENMASK(31, 6),
273};
274
275static const struct of_device_id st_rproc_match[] = {
276	{ .compatible = "st,st40-rproc", .data = &st40_rproc_cfg },
277	{ .compatible = "st,st231-rproc", .data = &st231_rproc_cfg },
278	{},
279};
280MODULE_DEVICE_TABLE(of, st_rproc_match);
281
282static int st_rproc_parse_dt(struct platform_device *pdev)
283{
284	struct device *dev = &pdev->dev;
285	struct rproc *rproc = platform_get_drvdata(pdev);
286	struct st_rproc *ddata = rproc->priv;
287	struct device_node *np = dev->of_node;
288	int err;
289
290	if (ddata->config->sw_reset) {
291		ddata->sw_reset = devm_reset_control_get_exclusive(dev,
292								   "sw_reset");
293		if (IS_ERR(ddata->sw_reset)) {
294			dev_err(dev, "Failed to get S/W Reset\n");
295			return PTR_ERR(ddata->sw_reset);
296		}
297	}
298
299	if (ddata->config->pwr_reset) {
300		ddata->pwr_reset = devm_reset_control_get_exclusive(dev,
301								    "pwr_reset");
302		if (IS_ERR(ddata->pwr_reset)) {
303			dev_err(dev, "Failed to get Power Reset\n");
304			return PTR_ERR(ddata->pwr_reset);
305		}
306	}
307
308	ddata->clk = devm_clk_get(dev, NULL);
309	if (IS_ERR(ddata->clk)) {
310		dev_err(dev, "Failed to get clock\n");
311		return PTR_ERR(ddata->clk);
312	}
313
314	err = of_property_read_u32(np, "clock-frequency", &ddata->clk_rate);
315	if (err) {
316		dev_err(dev, "failed to get clock frequency\n");
317		return err;
318	}
319
320	ddata->boot_base = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
321	if (IS_ERR(ddata->boot_base)) {
322		dev_err(dev, "Boot base not found\n");
323		return PTR_ERR(ddata->boot_base);
324	}
325
326	err = of_property_read_u32_index(np, "st,syscfg", 1,
327					 &ddata->boot_offset);
328	if (err) {
329		dev_err(dev, "Boot offset not found\n");
330		return -EINVAL;
331	}
332
333	err = clk_prepare(ddata->clk);
334	if (err)
335		dev_err(dev, "failed to get clock\n");
336
337	return err;
338}
339
340static int st_rproc_probe(struct platform_device *pdev)
341{
342	struct device *dev = &pdev->dev;
343	struct st_rproc *ddata;
344	struct device_node *np = dev->of_node;
345	struct rproc *rproc;
346	struct mbox_chan *chan;
347	int enabled;
348	int ret, i;
349
350	rproc = devm_rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
351	if (!rproc)
352		return -ENOMEM;
353
354	rproc->has_iommu = false;
355	ddata = rproc->priv;
356	ddata->config = (struct st_rproc_config *)device_get_match_data(dev);
357	if (!ddata->config)
358		return -ENODEV;
359
360	platform_set_drvdata(pdev, rproc);
361
362	ret = st_rproc_parse_dt(pdev);
363	if (ret)
364		return ret;
365
366	enabled = st_rproc_state(pdev);
367	if (enabled < 0) {
368		ret = enabled;
369		goto free_clk;
370	}
371
372	if (enabled) {
373		atomic_inc(&rproc->power);
374		rproc->state = RPROC_RUNNING;
375	} else {
376		clk_set_rate(ddata->clk, ddata->clk_rate);
377	}
378
379	if (of_property_present(np, "mbox-names")) {
380		ddata->mbox_client_vq0.dev		= dev;
381		ddata->mbox_client_vq0.tx_done		= NULL;
382		ddata->mbox_client_vq0.tx_block	= false;
383		ddata->mbox_client_vq0.knows_txdone	= false;
384		ddata->mbox_client_vq0.rx_callback	= st_rproc_mbox_callback_vq0;
385
386		ddata->mbox_client_vq1.dev		= dev;
387		ddata->mbox_client_vq1.tx_done		= NULL;
388		ddata->mbox_client_vq1.tx_block	= false;
389		ddata->mbox_client_vq1.knows_txdone	= false;
390		ddata->mbox_client_vq1.rx_callback	= st_rproc_mbox_callback_vq1;
391
392		/*
393		 * To control a co-processor without IPC mechanism.
394		 * This driver can be used without mbox and rpmsg.
395		 */
396		chan = mbox_request_channel_byname(&ddata->mbox_client_vq0, "vq0_rx");
397		if (IS_ERR(chan)) {
398			dev_err(&rproc->dev, "failed to request mbox chan 0\n");
399			ret = PTR_ERR(chan);
400			goto free_clk;
401		}
402		ddata->mbox_chan[ST_RPROC_VQ0 * MBOX_MAX + MBOX_RX] = chan;
403
404		chan = mbox_request_channel_byname(&ddata->mbox_client_vq0, "vq0_tx");
405		if (IS_ERR(chan)) {
406			dev_err(&rproc->dev, "failed to request mbox chan 0\n");
407			ret = PTR_ERR(chan);
408			goto free_mbox;
409		}
410		ddata->mbox_chan[ST_RPROC_VQ0 * MBOX_MAX + MBOX_TX] = chan;
411
412		chan = mbox_request_channel_byname(&ddata->mbox_client_vq1, "vq1_rx");
413		if (IS_ERR(chan)) {
414			dev_err(&rproc->dev, "failed to request mbox chan 1\n");
415			ret = PTR_ERR(chan);
416			goto free_mbox;
417		}
418		ddata->mbox_chan[ST_RPROC_VQ1 * MBOX_MAX + MBOX_RX] = chan;
419
420		chan = mbox_request_channel_byname(&ddata->mbox_client_vq1, "vq1_tx");
421		if (IS_ERR(chan)) {
422			dev_err(&rproc->dev, "failed to request mbox chan 1\n");
423			ret = PTR_ERR(chan);
424			goto free_mbox;
425		}
426		ddata->mbox_chan[ST_RPROC_VQ1 * MBOX_MAX + MBOX_TX] = chan;
427	}
428
429	ret = rproc_add(rproc);
430	if (ret)
431		goto free_mbox;
432
433	return 0;
434
435free_mbox:
436	for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
437		mbox_free_channel(ddata->mbox_chan[i]);
438free_clk:
439	clk_unprepare(ddata->clk);
440
441	return ret;
442}
443
444static void st_rproc_remove(struct platform_device *pdev)
445{
446	struct rproc *rproc = platform_get_drvdata(pdev);
447	struct st_rproc *ddata = rproc->priv;
448	int i;
449
450	rproc_del(rproc);
451
452	clk_disable_unprepare(ddata->clk);
453
454	for (i = 0; i < ST_RPROC_MAX_VRING * MBOX_MAX; i++)
455		mbox_free_channel(ddata->mbox_chan[i]);
456}
457
458static struct platform_driver st_rproc_driver = {
459	.probe = st_rproc_probe,
460	.remove_new = st_rproc_remove,
461	.driver = {
462		.name = "st-rproc",
463		.of_match_table = of_match_ptr(st_rproc_match),
464	},
465};
466module_platform_driver(st_rproc_driver);
467
468MODULE_DESCRIPTION("ST Remote Processor Control Driver");
469MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
470MODULE_LICENSE("GPL v2");
471