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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
21#include <linux/soc/sunxi/sunxi_sram.h>
22
23struct sunxi_sram_func {
24 char *func;
25 u8 val;
26};
27
28struct sunxi_sram_data {
29 char *name;
30 u8 reg;
31 u8 offset;
32 u8 width;
33 struct sunxi_sram_func *func;
34 struct list_head list;
35};
36
37struct sunxi_sram_desc {
38 struct sunxi_sram_data data;
39 bool claimed;
40};
41
42#define SUNXI_SRAM_MAP(_val, _func) \
43 { \
44 .func = _func, \
45 .val = _val, \
46 }
47
48#define SUNXI_SRAM_DATA(_name, _reg, _off, _width, ...) \
49 { \
50 .name = _name, \
51 .reg = _reg, \
52 .offset = _off, \
53 .width = _width, \
54 .func = (struct sunxi_sram_func[]){ \
55 __VA_ARGS__, { } }, \
56 }
57
58static struct sunxi_sram_desc sun4i_a10_sram_a3_a4 = {
59 .data = SUNXI_SRAM_DATA("A3-A4", 0x4, 0x4, 2,
60 SUNXI_SRAM_MAP(0, "cpu"),
61 SUNXI_SRAM_MAP(1, "emac")),
62};
63
64static struct sunxi_sram_desc sun4i_a10_sram_d = {
65 .data = SUNXI_SRAM_DATA("D", 0x4, 0x0, 1,
66 SUNXI_SRAM_MAP(0, "cpu"),
67 SUNXI_SRAM_MAP(1, "usb-otg")),
68};
69
70static const struct of_device_id sunxi_sram_dt_ids[] = {
71 {
72 .compatible = "allwinner,sun4i-a10-sram-a3-a4",
73 .data = &sun4i_a10_sram_a3_a4.data,
74 },
75 {
76 .compatible = "allwinner,sun4i-a10-sram-d",
77 .data = &sun4i_a10_sram_d.data,
78 },
79 {}
80};
81
82static struct device *sram_dev;
83static LIST_HEAD(claimed_sram);
84static DEFINE_SPINLOCK(sram_lock);
85static void __iomem *base;
86
87static int sunxi_sram_show(struct seq_file *s, void *data)
88{
89 struct device_node *sram_node, *section_node;
90 const struct sunxi_sram_data *sram_data;
91 const struct of_device_id *match;
92 struct sunxi_sram_func *func;
93 const __be32 *sram_addr_p, *section_addr_p;
94 u32 val;
95
96 seq_puts(s, "Allwinner sunXi SRAM\n");
97 seq_puts(s, "--------------------\n\n");
98
99 for_each_child_of_node(sram_dev->of_node, sram_node) {
100 sram_addr_p = of_get_address(sram_node, 0, NULL, NULL);
101
102 seq_printf(s, "sram@%08x\n",
103 be32_to_cpu(*sram_addr_p));
104
105 for_each_child_of_node(sram_node, section_node) {
106 match = of_match_node(sunxi_sram_dt_ids, section_node);
107 if (!match)
108 continue;
109 sram_data = match->data;
110
111 section_addr_p = of_get_address(section_node, 0,
112 NULL, NULL);
113
114 seq_printf(s, "\tsection@%04x\t(%s)\n",
115 be32_to_cpu(*section_addr_p),
116 sram_data->name);
117
118 val = readl(base + sram_data->reg);
119 val >>= sram_data->offset;
120 val &= GENMASK(sram_data->width - 1, 0);
121
122 for (func = sram_data->func; func->func; func++) {
123 seq_printf(s, "\t\t%s%c\n", func->func,
124 func->val == val ? '*' : ' ');
125 }
126 }
127
128 seq_puts(s, "\n");
129 }
130
131 return 0;
132}
133
134static int sunxi_sram_open(struct inode *inode, struct file *file)
135{
136 return single_open(file, sunxi_sram_show, inode->i_private);
137}
138
139static const struct file_operations sunxi_sram_fops = {
140 .open = sunxi_sram_open,
141 .read = seq_read,
142 .llseek = seq_lseek,
143 .release = single_release,
144};
145
146static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data)
147{
148 return container_of(data, struct sunxi_sram_desc, data);
149}
150
151static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node,
152 unsigned int *value)
153{
154 const struct of_device_id *match;
155 struct of_phandle_args args;
156 int ret;
157
158 ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0,
159 &args);
160 if (ret)
161 return ERR_PTR(ret);
162
163 if (!of_device_is_available(args.np)) {
164 ret = -EBUSY;
165 goto err;
166 }
167
168 if (value)
169 *value = args.args[0];
170
171 match = of_match_node(sunxi_sram_dt_ids, args.np);
172 if (!match) {
173 ret = -EINVAL;
174 goto err;
175 }
176
177 of_node_put(args.np);
178 return match->data;
179
180err:
181 of_node_put(args.np);
182 return ERR_PTR(ret);
183}
184
185int sunxi_sram_claim(struct device *dev)
186{
187 const struct sunxi_sram_data *sram_data;
188 struct sunxi_sram_desc *sram_desc;
189 unsigned int device;
190 u32 val, mask;
191
192 if (IS_ERR(base))
193 return -EPROBE_DEFER;
194
195 if (!dev || !dev->of_node)
196 return -EINVAL;
197
198 sram_data = sunxi_sram_of_parse(dev->of_node, &device);
199 if (IS_ERR(sram_data))
200 return PTR_ERR(sram_data);
201
202 sram_desc = to_sram_desc(sram_data);
203
204 spin_lock(&sram_lock);
205
206 if (sram_desc->claimed) {
207 spin_unlock(&sram_lock);
208 return -EBUSY;
209 }
210
211 mask = GENMASK(sram_data->offset + sram_data->width - 1,
212 sram_data->offset);
213 val = readl(base + sram_data->reg);
214 val &= ~mask;
215 writel(val | ((device << sram_data->offset) & mask),
216 base + sram_data->reg);
217
218 spin_unlock(&sram_lock);
219
220 return 0;
221}
222EXPORT_SYMBOL(sunxi_sram_claim);
223
224int sunxi_sram_release(struct device *dev)
225{
226 const struct sunxi_sram_data *sram_data;
227 struct sunxi_sram_desc *sram_desc;
228
229 if (!dev || !dev->of_node)
230 return -EINVAL;
231
232 sram_data = sunxi_sram_of_parse(dev->of_node, NULL);
233 if (IS_ERR(sram_data))
234 return -EINVAL;
235
236 sram_desc = to_sram_desc(sram_data);
237
238 spin_lock(&sram_lock);
239 sram_desc->claimed = false;
240 spin_unlock(&sram_lock);
241
242 return 0;
243}
244EXPORT_SYMBOL(sunxi_sram_release);
245
246static int sunxi_sram_probe(struct platform_device *pdev)
247{
248 struct resource *res;
249 struct dentry *d;
250
251 sram_dev = &pdev->dev;
252
253 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
254 base = devm_ioremap_resource(&pdev->dev, res);
255 if (IS_ERR(base))
256 return PTR_ERR(base);
257
258 of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
259
260 d = debugfs_create_file("sram", S_IRUGO, NULL, NULL,
261 &sunxi_sram_fops);
262 if (!d)
263 return -ENOMEM;
264
265 return 0;
266}
267
268static const struct of_device_id sunxi_sram_dt_match[] = {
269 { .compatible = "allwinner,sun4i-a10-sram-controller" },
270 { },
271};
272MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);
273
274static struct platform_driver sunxi_sram_driver = {
275 .driver = {
276 .name = "sunxi-sram",
277 .of_match_table = sunxi_sram_dt_match,
278 },
279 .probe = sunxi_sram_probe,
280};
281module_platform_driver(sunxi_sram_driver);
282
283MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
284MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");
285MODULE_LICENSE("GPL");
286
