xref: /openbmc/linux/drivers/soc/sunxi/sunxi_sram.c (revision ca637c0e)
1 /*
2  * Allwinner SoCs SRAM Controller Driver
3  *
4  * Copyright (C) 2015 Maxime Ripard
5  *
6  * Author: Maxime Ripard <maxime.ripard@free-electrons.com>
7  *
8  * This file is licensed under the terms of the GNU General Public
9  * License version 2.  This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12 
13 #include <linux/debugfs.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_address.h>
18 #include <linux/of_device.h>
19 #include <linux/platform_device.h>
20 #include <linux/regmap.h>
21 
22 #include <linux/soc/sunxi/sunxi_sram.h>
23 
24 struct sunxi_sram_func {
25 	char	*func;
26 	u8	val;
27 	u32	reg_val;
28 };
29 
30 struct sunxi_sram_data {
31 	char			*name;
32 	u8			reg;
33 	u8			offset;
34 	u8			width;
35 	struct sunxi_sram_func	*func;
36 	struct list_head	list;
37 };
38 
39 struct sunxi_sram_desc {
40 	struct sunxi_sram_data	data;
41 	bool			claimed;
42 };
43 
44 #define SUNXI_SRAM_MAP(_reg_val, _val, _func)			\
45 	{							\
46 		.func = _func,					\
47 		.val = _val,					\
48 		.reg_val = _reg_val,				\
49 	}
50 
51 #define SUNXI_SRAM_DATA(_name, _reg, _off, _width, ...)		\
52 	{							\
53 		.name = _name,					\
54 		.reg = _reg,					\
55 		.offset = _off,					\
56 		.width = _width,				\
57 		.func = (struct sunxi_sram_func[]){		\
58 			__VA_ARGS__, { } },			\
59 	}
60 
61 static struct sunxi_sram_desc sun4i_a10_sram_a3_a4 = {
62 	.data	= SUNXI_SRAM_DATA("A3-A4", 0x4, 0x4, 2,
63 				  SUNXI_SRAM_MAP(0, 0, "cpu"),
64 				  SUNXI_SRAM_MAP(1, 1, "emac")),
65 };
66 
67 static struct sunxi_sram_desc sun4i_a10_sram_c1 = {
68 	.data	= SUNXI_SRAM_DATA("C1", 0x0, 0x0, 31,
69 				  SUNXI_SRAM_MAP(0, 0, "cpu"),
70 				  SUNXI_SRAM_MAP(0x7fffffff, 1, "ve")),
71 };
72 
73 static struct sunxi_sram_desc sun4i_a10_sram_d = {
74 	.data	= SUNXI_SRAM_DATA("D", 0x4, 0x0, 1,
75 				  SUNXI_SRAM_MAP(0, 0, "cpu"),
76 				  SUNXI_SRAM_MAP(1, 1, "usb-otg")),
77 };
78 
79 static struct sunxi_sram_desc sun50i_a64_sram_c = {
80 	.data	= SUNXI_SRAM_DATA("C", 0x4, 24, 1,
81 				  SUNXI_SRAM_MAP(1, 0, "cpu"),
82 				  SUNXI_SRAM_MAP(0, 1, "de2")),
83 };
84 
85 static const struct of_device_id sunxi_sram_dt_ids[] = {
86 	{
87 		.compatible	= "allwinner,sun4i-a10-sram-a3-a4",
88 		.data		= &sun4i_a10_sram_a3_a4.data,
89 	},
90 	{
91 		.compatible	= "allwinner,sun4i-a10-sram-c1",
92 		.data		= &sun4i_a10_sram_c1.data,
93 	},
94 	{
95 		.compatible	= "allwinner,sun4i-a10-sram-d",
96 		.data		= &sun4i_a10_sram_d.data,
97 	},
98 	{
99 		.compatible	= "allwinner,sun50i-a64-sram-c",
100 		.data		= &sun50i_a64_sram_c.data,
101 	},
102 	{}
103 };
104 
105 static struct device *sram_dev;
106 static LIST_HEAD(claimed_sram);
107 static DEFINE_SPINLOCK(sram_lock);
108 static void __iomem *base;
109 
110 static int sunxi_sram_show(struct seq_file *s, void *data)
111 {
112 	struct device_node *sram_node, *section_node;
113 	const struct sunxi_sram_data *sram_data;
114 	const struct of_device_id *match;
115 	struct sunxi_sram_func *func;
116 	const __be32 *sram_addr_p, *section_addr_p;
117 	u32 val;
118 
119 	seq_puts(s, "Allwinner sunXi SRAM\n");
120 	seq_puts(s, "--------------------\n\n");
121 
122 	for_each_child_of_node(sram_dev->of_node, sram_node) {
123 		sram_addr_p = of_get_address(sram_node, 0, NULL, NULL);
124 
125 		seq_printf(s, "sram@%08x\n",
126 			   be32_to_cpu(*sram_addr_p));
127 
128 		for_each_child_of_node(sram_node, section_node) {
129 			match = of_match_node(sunxi_sram_dt_ids, section_node);
130 			if (!match)
131 				continue;
132 			sram_data = match->data;
133 
134 			section_addr_p = of_get_address(section_node, 0,
135 							NULL, NULL);
136 
137 			seq_printf(s, "\tsection@%04x\t(%s)\n",
138 				   be32_to_cpu(*section_addr_p),
139 				   sram_data->name);
140 
141 			val = readl(base + sram_data->reg);
142 			val >>= sram_data->offset;
143 			val &= GENMASK(sram_data->width - 1, 0);
144 
145 			for (func = sram_data->func; func->func; func++) {
146 				seq_printf(s, "\t\t%s%c\n", func->func,
147 					   func->reg_val == val ?
148 					   '*' : ' ');
149 			}
150 		}
151 
152 		seq_puts(s, "\n");
153 	}
154 
155 	return 0;
156 }
157 
158 DEFINE_SHOW_ATTRIBUTE(sunxi_sram);
159 
160 static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data)
161 {
162 	return container_of(data, struct sunxi_sram_desc, data);
163 }
164 
165 static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node,
166 							 unsigned int *reg_value)
167 {
168 	const struct of_device_id *match;
169 	const struct sunxi_sram_data *data;
170 	struct sunxi_sram_func *func;
171 	struct of_phandle_args args;
172 	u8 val;
173 	int ret;
174 
175 	ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0,
176 					       &args);
177 	if (ret)
178 		return ERR_PTR(ret);
179 
180 	if (!of_device_is_available(args.np)) {
181 		ret = -EBUSY;
182 		goto err;
183 	}
184 
185 	val = args.args[0];
186 
187 	match = of_match_node(sunxi_sram_dt_ids, args.np);
188 	if (!match) {
189 		ret = -EINVAL;
190 		goto err;
191 	}
192 
193 	data = match->data;
194 	if (!data) {
195 		ret = -EINVAL;
196 		goto err;
197 	}
198 
199 	for (func = data->func; func->func; func++) {
200 		if (val == func->val) {
201 			if (reg_value)
202 				*reg_value = func->reg_val;
203 
204 			break;
205 		}
206 	}
207 
208 	if (!func->func) {
209 		ret = -EINVAL;
210 		goto err;
211 	}
212 
213 	of_node_put(args.np);
214 	return match->data;
215 
216 err:
217 	of_node_put(args.np);
218 	return ERR_PTR(ret);
219 }
220 
221 int sunxi_sram_claim(struct device *dev)
222 {
223 	const struct sunxi_sram_data *sram_data;
224 	struct sunxi_sram_desc *sram_desc;
225 	unsigned int device;
226 	u32 val, mask;
227 
228 	if (IS_ERR(base))
229 		return PTR_ERR(base);
230 
231 	if (!base)
232 		return -EPROBE_DEFER;
233 
234 	if (!dev || !dev->of_node)
235 		return -EINVAL;
236 
237 	sram_data = sunxi_sram_of_parse(dev->of_node, &device);
238 	if (IS_ERR(sram_data))
239 		return PTR_ERR(sram_data);
240 
241 	sram_desc = to_sram_desc(sram_data);
242 
243 	spin_lock(&sram_lock);
244 
245 	if (sram_desc->claimed) {
246 		spin_unlock(&sram_lock);
247 		return -EBUSY;
248 	}
249 
250 	mask = GENMASK(sram_data->offset + sram_data->width - 1,
251 		       sram_data->offset);
252 	val = readl(base + sram_data->reg);
253 	val &= ~mask;
254 	writel(val | ((device << sram_data->offset) & mask),
255 	       base + sram_data->reg);
256 
257 	sram_desc->claimed = true;
258 	spin_unlock(&sram_lock);
259 
260 	return 0;
261 }
262 EXPORT_SYMBOL(sunxi_sram_claim);
263 
264 void sunxi_sram_release(struct device *dev)
265 {
266 	const struct sunxi_sram_data *sram_data;
267 	struct sunxi_sram_desc *sram_desc;
268 
269 	if (!dev || !dev->of_node)
270 		return;
271 
272 	sram_data = sunxi_sram_of_parse(dev->of_node, NULL);
273 	if (IS_ERR(sram_data))
274 		return;
275 
276 	sram_desc = to_sram_desc(sram_data);
277 
278 	spin_lock(&sram_lock);
279 	sram_desc->claimed = false;
280 	spin_unlock(&sram_lock);
281 }
282 EXPORT_SYMBOL(sunxi_sram_release);
283 
284 struct sunxi_sramc_variant {
285 	int num_emac_clocks;
286 	bool has_ldo_ctrl;
287 };
288 
289 static const struct sunxi_sramc_variant sun4i_a10_sramc_variant = {
290 	/* Nothing special */
291 };
292 
293 static const struct sunxi_sramc_variant sun8i_h3_sramc_variant = {
294 	.num_emac_clocks = 1,
295 };
296 
297 static const struct sunxi_sramc_variant sun20i_d1_sramc_variant = {
298 	.num_emac_clocks = 1,
299 	.has_ldo_ctrl = true,
300 };
301 
302 static const struct sunxi_sramc_variant sun50i_a64_sramc_variant = {
303 	.num_emac_clocks = 1,
304 };
305 
306 static const struct sunxi_sramc_variant sun50i_h616_sramc_variant = {
307 	.num_emac_clocks = 2,
308 };
309 
310 #define SUNXI_SRAM_EMAC_CLOCK_REG	0x30
311 #define SUNXI_SYS_LDO_CTRL_REG		0x150
312 
313 static bool sunxi_sram_regmap_accessible_reg(struct device *dev,
314 					     unsigned int reg)
315 {
316 	const struct sunxi_sramc_variant *variant = dev_get_drvdata(dev);
317 
318 	if (reg >= SUNXI_SRAM_EMAC_CLOCK_REG &&
319 	    reg <  SUNXI_SRAM_EMAC_CLOCK_REG + variant->num_emac_clocks * 4)
320 		return true;
321 	if (reg == SUNXI_SYS_LDO_CTRL_REG && variant->has_ldo_ctrl)
322 		return true;
323 
324 	return false;
325 }
326 
327 static struct regmap_config sunxi_sram_regmap_config = {
328 	.reg_bits       = 32,
329 	.val_bits       = 32,
330 	.reg_stride     = 4,
331 	/* last defined register */
332 	.max_register   = SUNXI_SYS_LDO_CTRL_REG,
333 	/* other devices have no business accessing other registers */
334 	.readable_reg	= sunxi_sram_regmap_accessible_reg,
335 	.writeable_reg	= sunxi_sram_regmap_accessible_reg,
336 };
337 
338 static int __init sunxi_sram_probe(struct platform_device *pdev)
339 {
340 	const struct sunxi_sramc_variant *variant;
341 	struct device *dev = &pdev->dev;
342 	struct regmap *regmap;
343 
344 	sram_dev = &pdev->dev;
345 
346 	variant = of_device_get_match_data(&pdev->dev);
347 	if (!variant)
348 		return -EINVAL;
349 
350 	dev_set_drvdata(dev, (struct sunxi_sramc_variant *)variant);
351 
352 	base = devm_platform_ioremap_resource(pdev, 0);
353 	if (IS_ERR(base))
354 		return PTR_ERR(base);
355 
356 	if (variant->num_emac_clocks || variant->has_ldo_ctrl) {
357 		regmap = devm_regmap_init_mmio(dev, base, &sunxi_sram_regmap_config);
358 		if (IS_ERR(regmap))
359 			return PTR_ERR(regmap);
360 	}
361 
362 	of_platform_populate(dev->of_node, NULL, NULL, dev);
363 
364 	debugfs_create_file("sram", 0444, NULL, NULL, &sunxi_sram_fops);
365 
366 	return 0;
367 }
368 
369 static const struct of_device_id sunxi_sram_dt_match[] = {
370 	{
371 		.compatible = "allwinner,sun4i-a10-sram-controller",
372 		.data = &sun4i_a10_sramc_variant,
373 	},
374 	{
375 		.compatible = "allwinner,sun4i-a10-system-control",
376 		.data = &sun4i_a10_sramc_variant,
377 	},
378 	{
379 		.compatible = "allwinner,sun5i-a13-system-control",
380 		.data = &sun4i_a10_sramc_variant,
381 	},
382 	{
383 		.compatible = "allwinner,sun8i-a23-system-control",
384 		.data = &sun4i_a10_sramc_variant,
385 	},
386 	{
387 		.compatible = "allwinner,sun8i-h3-system-control",
388 		.data = &sun8i_h3_sramc_variant,
389 	},
390 	{
391 		.compatible = "allwinner,sun20i-d1-system-control",
392 		.data = &sun20i_d1_sramc_variant,
393 	},
394 	{
395 		.compatible = "allwinner,sun50i-a64-sram-controller",
396 		.data = &sun50i_a64_sramc_variant,
397 	},
398 	{
399 		.compatible = "allwinner,sun50i-a64-system-control",
400 		.data = &sun50i_a64_sramc_variant,
401 	},
402 	{
403 		.compatible = "allwinner,sun50i-h5-system-control",
404 		.data = &sun50i_a64_sramc_variant,
405 	},
406 	{
407 		.compatible = "allwinner,sun50i-h616-system-control",
408 		.data = &sun50i_h616_sramc_variant,
409 	},
410 	{ },
411 };
412 MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);
413 
414 static struct platform_driver sunxi_sram_driver = {
415 	.driver = {
416 		.name		= "sunxi-sram",
417 		.of_match_table	= sunxi_sram_dt_match,
418 	},
419 };
420 builtin_platform_driver_probe(sunxi_sram_driver, sunxi_sram_probe);
421 
422 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
423 MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");
424 MODULE_LICENSE("GPL");
425