summaryrefslogtreecommitdiffstats
path: root/drivers/soc/sunxi/sunxi_sram.c
blob: bc52670c8f4b33a9b8181d19e89566a3c87f3c69 (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
/*
 * Allwinner SoCs SRAM Controller Driver
 *
 * Copyright (C) 2015 Maxime Ripard
 *
 * Author: Maxime Ripard <maxime.ripard@free-electrons.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/debugfs.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>

#include <linux/soc/sunxi/sunxi_sram.h>

struct sunxi_sram_func {
	char	*func;
	u8	val;
};

struct sunxi_sram_data {
	char			*name;
	u8			reg;
	u8			offset;
	u8			width;
	struct sunxi_sram_func	*func;
	struct list_head	list;
};

struct sunxi_sram_desc {
	struct sunxi_sram_data	data;
	bool			claimed;
};

#define SUNXI_SRAM_MAP(_val, _func)				\
	{							\
		.func = _func,					\
		.val = _val,					\
	}

#define SUNXI_SRAM_DATA(_name, _reg, _off, _width, ...)		\
	{							\
		.name = _name,					\
		.reg = _reg,					\
		.offset = _off,					\
		.width = _width,				\
		.func = (struct sunxi_sram_func[]){		\
			__VA_ARGS__, { } },			\
	}

static struct sunxi_sram_desc sun4i_a10_sram_a3_a4 = {
	.data	= SUNXI_SRAM_DATA("A3-A4", 0x4, 0x4, 2,
				  SUNXI_SRAM_MAP(0, "cpu"),
				  SUNXI_SRAM_MAP(1, "emac")),
};

static struct sunxi_sram_desc sun4i_a10_sram_d = {
	.data	= SUNXI_SRAM_DATA("D", 0x4, 0x0, 1,
				  SUNXI_SRAM_MAP(0, "cpu"),
				  SUNXI_SRAM_MAP(1, "usb-otg")),
};

static const struct of_device_id sunxi_sram_dt_ids[] = {
	{
		.compatible	= "allwinner,sun4i-a10-sram-a3-a4",
		.data		= &sun4i_a10_sram_a3_a4.data,
	},
	{
		.compatible	= "allwinner,sun4i-a10-sram-d",
		.data		= &sun4i_a10_sram_d.data,
	},
	{}
};

static struct device *sram_dev;
static LIST_HEAD(claimed_sram);
static DEFINE_SPINLOCK(sram_lock);
static void __iomem *base;

static int sunxi_sram_show(struct seq_file *s, void *data)
{
	struct device_node *sram_node, *section_node;
	const struct sunxi_sram_data *sram_data;
	const struct of_device_id *match;
	struct sunxi_sram_func *func;
	const __be32 *sram_addr_p, *section_addr_p;
	u32 val;

	seq_puts(s, "Allwinner sunXi SRAM\n");
	seq_puts(s, "--------------------\n\n");

	for_each_child_of_node(sram_dev->of_node, sram_node) {
		sram_addr_p = of_get_address(sram_node, 0, NULL, NULL);

		seq_printf(s, "sram@%08x\n",
			   be32_to_cpu(*sram_addr_p));

		for_each_child_of_node(sram_node, section_node) {
			match = of_match_node(sunxi_sram_dt_ids, section_node);
			if (!match)
				continue;
			sram_data = match->data;

			section_addr_p = of_get_address(section_node, 0,
							NULL, NULL);

			seq_printf(s, "\tsection@%04x\t(%s)\n",
				   be32_to_cpu(*section_addr_p),
				   sram_data->name);

			val = readl(base + sram_data->reg);
			val >>= sram_data->offset;
			val &= sram_data->width;

			for (func = sram_data->func; func->func; func++) {
				seq_printf(s, "\t\t%s%c\n", func->func,
					   func->val == val ? '*' : ' ');
			}
		}

		seq_puts(s, "\n");
	}

	return 0;
}

static int sunxi_sram_open(struct inode *inode, struct file *file)
{
	return single_open(file, sunxi_sram_show, inode->i_private);
}

static const struct file_operations sunxi_sram_fops = {
	.open = sunxi_sram_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data)
{
	return container_of(data, struct sunxi_sram_desc, data);
}

static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node,
							 unsigned int *value)
{
	const struct of_device_id *match;
	struct of_phandle_args args;
	int ret;

	ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0,
					       &args);
	if (ret)
		return ERR_PTR(ret);

	if (!of_device_is_available(args.np)) {
		ret = -EBUSY;
		goto err;
	}

	if (value)
		*value = args.args[0];

	match = of_match_node(sunxi_sram_dt_ids, args.np);
	if (!match) {
		ret = -EINVAL;
		goto err;
	}

	of_node_put(args.np);
	return match->data;

err:
	of_node_put(args.np);
	return ERR_PTR(ret);
}

int sunxi_sram_claim(struct device *dev)
{
	const struct sunxi_sram_data *sram_data;
	struct sunxi_sram_desc *sram_desc;
	unsigned int device;
	u32 val, mask;

	if (IS_ERR(base))
		return -EPROBE_DEFER;

	if (!dev || !dev->of_node)
		return -EINVAL;

	sram_data = sunxi_sram_of_parse(dev->of_node, &device);
	if (IS_ERR(sram_data))
		return PTR_ERR(sram_data);

	sram_desc = to_sram_desc(sram_data);

	spin_lock(&sram_lock);

	if (sram_desc->claimed) {
		spin_unlock(&sram_lock);
		return -EBUSY;
	}

	mask = GENMASK(sram_data->offset + sram_data->width, sram_data->offset);
	val = readl(base + sram_data->reg);
	val &= ~mask;
	writel(val | ((device << sram_data->offset) & mask),
	       base + sram_data->reg);

	spin_unlock(&sram_lock);

	return 0;
}
EXPORT_SYMBOL(sunxi_sram_claim);

int sunxi_sram_release(struct device *dev)
{
	const struct sunxi_sram_data *sram_data;
	struct sunxi_sram_desc *sram_desc;

	if (!dev || !dev->of_node)
		return -EINVAL;

	sram_data = sunxi_sram_of_parse(dev->of_node, NULL);
	if (IS_ERR(sram_data))
		return -EINVAL;

	sram_desc = to_sram_desc(sram_data);

	spin_lock(&sram_lock);
	sram_desc->claimed = false;
	spin_unlock(&sram_lock);

	return 0;
}
EXPORT_SYMBOL(sunxi_sram_release);

static int sunxi_sram_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct dentry *d;

	sram_dev = &pdev->dev;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(base))
		return PTR_ERR(base);

	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);

	d = debugfs_create_file("sram", S_IRUGO, NULL, NULL,
				&sunxi_sram_fops);
	if (!d)
		return -ENOMEM;

	return 0;
}

static const struct of_device_id sunxi_sram_dt_match[] = {
	{ .compatible = "allwinner,sun4i-a10-sram-controller" },
	{ },
};
MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);

static struct platform_driver sunxi_sram_driver = {
	.driver = {
		.name		= "sunxi-sram",
		.of_match_table	= sunxi_sram_dt_match,
	},
	.probe	= sunxi_sram_probe,
};
module_platform_driver(sunxi_sram_driver);

MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");
MODULE_LICENSE("GPL");