summaryrefslogtreecommitdiff
path: root/drivers/remoteproc/st_remoteproc.c
blob: 6bb04d453247ced25ed92e854888d6854b50f882 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
/*
 * ST's Remote Processor Control Driver
 *
 * Copyright (C) 2015 STMicroelectronics - All Rights Reserved
 *
 * Author: Ludovic Barre <ludovic.barre@st.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_reserved_mem.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/remoteproc.h>
#include <linux/reset.h>

struct st_rproc_config {
	bool			sw_reset;
	bool			pwr_reset;
	unsigned long		bootaddr_mask;
};

struct st_rproc {
	struct st_rproc_config	*config;
	struct reset_control	*sw_reset;
	struct reset_control	*pwr_reset;
	struct clk		*clk;
	u32			clk_rate;
	struct regmap		*boot_base;
	u32			boot_offset;
};

static int st_rproc_start(struct rproc *rproc)
{
	struct st_rproc *ddata = rproc->priv;
	int err;

	regmap_update_bits(ddata->boot_base, ddata->boot_offset,
			   ddata->config->bootaddr_mask, rproc->bootaddr);

	err = clk_enable(ddata->clk);
	if (err) {
		dev_err(&rproc->dev, "Failed to enable clock\n");
		return err;
	}

	if (ddata->config->sw_reset) {
		err = reset_control_deassert(ddata->sw_reset);
		if (err) {
			dev_err(&rproc->dev, "Failed to deassert S/W Reset\n");
			goto sw_reset_fail;
		}
	}

	if (ddata->config->pwr_reset) {
		err = reset_control_deassert(ddata->pwr_reset);
		if (err) {
			dev_err(&rproc->dev, "Failed to deassert Power Reset\n");
			goto pwr_reset_fail;
		}
	}

	dev_info(&rproc->dev, "Started from 0x%x\n", rproc->bootaddr);

	return 0;


pwr_reset_fail:
	if (ddata->config->pwr_reset)
		reset_control_assert(ddata->sw_reset);
sw_reset_fail:
	clk_disable(ddata->clk);

	return err;
}

static int st_rproc_stop(struct rproc *rproc)
{
	struct st_rproc *ddata = rproc->priv;
	int sw_err = 0, pwr_err = 0;

	if (ddata->config->sw_reset) {
		sw_err = reset_control_assert(ddata->sw_reset);
		if (sw_err)
			dev_err(&rproc->dev, "Failed to assert S/W Reset\n");
	}

	if (ddata->config->pwr_reset) {
		pwr_err = reset_control_assert(ddata->pwr_reset);
		if (pwr_err)
			dev_err(&rproc->dev, "Failed to assert Power Reset\n");
	}

	clk_disable(ddata->clk);

	return sw_err ?: pwr_err;
}

static struct rproc_ops st_rproc_ops = {
	.start		= st_rproc_start,
	.stop		= st_rproc_stop,
};

/*
 * Fetch state of the processor: 0 is off, 1 is on.
 */
static int st_rproc_state(struct platform_device *pdev)
{
	struct rproc *rproc = platform_get_drvdata(pdev);
	struct st_rproc *ddata = rproc->priv;
	int reset_sw = 0, reset_pwr = 0;

	if (ddata->config->sw_reset)
		reset_sw = reset_control_status(ddata->sw_reset);

	if (ddata->config->pwr_reset)
		reset_pwr = reset_control_status(ddata->pwr_reset);

	if (reset_sw < 0 || reset_pwr < 0)
		return -EINVAL;

	return !reset_sw && !reset_pwr;
}

static const struct st_rproc_config st40_rproc_cfg = {
	.sw_reset = true,
	.pwr_reset = true,
	.bootaddr_mask = GENMASK(28, 1),
};

static const struct st_rproc_config st231_rproc_cfg = {
	.sw_reset = true,
	.pwr_reset = false,
	.bootaddr_mask = GENMASK(31, 6),
};

static const struct of_device_id st_rproc_match[] = {
	{ .compatible = "st,st40-rproc", .data = &st40_rproc_cfg },
	{ .compatible = "st,st231-rproc", .data = &st231_rproc_cfg },
	{},
};
MODULE_DEVICE_TABLE(of, st_rproc_match);

static int st_rproc_parse_dt(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct rproc *rproc = platform_get_drvdata(pdev);
	struct st_rproc *ddata = rproc->priv;
	struct device_node *np = dev->of_node;
	int err;

	if (ddata->config->sw_reset) {
		ddata->sw_reset = devm_reset_control_get(dev, "sw_reset");
		if (IS_ERR(ddata->sw_reset)) {
			dev_err(dev, "Failed to get S/W Reset\n");
			return PTR_ERR(ddata->sw_reset);
		}
	}

	if (ddata->config->pwr_reset) {
		ddata->pwr_reset = devm_reset_control_get(dev, "pwr_reset");
		if (IS_ERR(ddata->pwr_reset)) {
			dev_err(dev, "Failed to get Power Reset\n");
			return PTR_ERR(ddata->pwr_reset);
		}
	}

	ddata->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(ddata->clk)) {
		dev_err(dev, "Failed to get clock\n");
		return PTR_ERR(ddata->clk);
	}

	err = of_property_read_u32(np, "clock-frequency", &ddata->clk_rate);
	if (err) {
		dev_err(dev, "failed to get clock frequency\n");
		return err;
	}

	ddata->boot_base = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
	if (!ddata->boot_base) {
		dev_err(dev, "Boot base not found\n");
		return -EINVAL;
	}

	err = of_property_read_u32_index(np, "st,syscfg", 1,
					 &ddata->boot_offset);
	if (err) {
		dev_err(dev, "Boot offset not found\n");
		return -EINVAL;
	}

	err = of_reserved_mem_device_init(dev);
	if (err) {
		dev_err(dev, "Failed to obtain shared memory\n");
		return err;
	}

	err = clk_prepare(ddata->clk);
	if (err)
		dev_err(dev, "failed to get clock\n");

	return err;
}

static int st_rproc_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	const struct of_device_id *match;
	struct st_rproc *ddata;
	struct device_node *np = dev->of_node;
	struct rproc *rproc;
	int enabled;
	int ret;

	match = of_match_device(st_rproc_match, dev);
	if (!match || !match->data) {
		dev_err(dev, "No device match found\n");
		return -ENODEV;
	}

	rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
	if (!rproc)
		return -ENOMEM;

	rproc->has_iommu = false;
	ddata = rproc->priv;
	ddata->config = (struct st_rproc_config *)match->data;

	platform_set_drvdata(pdev, rproc);

	ret = st_rproc_parse_dt(pdev);
	if (ret)
		goto free_rproc;

	enabled = st_rproc_state(pdev);
	if (enabled < 0)
		goto free_rproc;

	if (enabled) {
		atomic_inc(&rproc->power);
		rproc->state = RPROC_RUNNING;
	} else {
		clk_set_rate(ddata->clk, ddata->clk_rate);
	}

	ret = rproc_add(rproc);
	if (ret)
		goto free_rproc;

	return 0;

free_rproc:
	rproc_put(rproc);
	return ret;
}

static int st_rproc_remove(struct platform_device *pdev)
{
	struct rproc *rproc = platform_get_drvdata(pdev);
	struct st_rproc *ddata = rproc->priv;

	rproc_del(rproc);

	clk_disable_unprepare(ddata->clk);

	of_reserved_mem_device_release(&pdev->dev);

	rproc_put(rproc);

	return 0;
}

static struct platform_driver st_rproc_driver = {
	.probe = st_rproc_probe,
	.remove = st_rproc_remove,
	.driver = {
		.name = "st-rproc",
		.of_match_table = of_match_ptr(st_rproc_match),
	},
};
module_platform_driver(st_rproc_driver);

MODULE_DESCRIPTION("ST Remote Processor Control Driver");
MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
MODULE_LICENSE("GPL v2");