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 21 #include <linux/soc/sunxi/sunxi_sram.h> 22 23 struct sunxi_sram_func { 24 char *func; 25 u8 val; 26 u32 reg_val; 27 }; 28 29 struct sunxi_sram_data { 30 char *name; 31 u8 reg; 32 u8 offset; 33 u8 width; 34 struct sunxi_sram_func *func; 35 struct list_head list; 36 }; 37 38 struct sunxi_sram_desc { 39 struct sunxi_sram_data data; 40 bool claimed; 41 }; 42 43 #define SUNXI_SRAM_MAP(_reg_val, _val, _func) \ 44 { \ 45 .func = _func, \ 46 .val = _val, \ 47 .reg_val = _reg_val, \ 48 } 49 50 #define SUNXI_SRAM_DATA(_name, _reg, _off, _width, ...) \ 51 { \ 52 .name = _name, \ 53 .reg = _reg, \ 54 .offset = _off, \ 55 .width = _width, \ 56 .func = (struct sunxi_sram_func[]){ \ 57 __VA_ARGS__, { } }, \ 58 } 59 60 static struct sunxi_sram_desc sun4i_a10_sram_a3_a4 = { 61 .data = SUNXI_SRAM_DATA("A3-A4", 0x4, 0x4, 2, 62 SUNXI_SRAM_MAP(0, 0, "cpu"), 63 SUNXI_SRAM_MAP(1, 1, "emac")), 64 }; 65 66 static struct sunxi_sram_desc sun4i_a10_sram_d = { 67 .data = SUNXI_SRAM_DATA("D", 0x4, 0x0, 1, 68 SUNXI_SRAM_MAP(0, 0, "cpu"), 69 SUNXI_SRAM_MAP(1, 1, "usb-otg")), 70 }; 71 72 static struct sunxi_sram_desc sun50i_a64_sram_c = { 73 .data = SUNXI_SRAM_DATA("C", 0x4, 24, 1, 74 SUNXI_SRAM_MAP(0, 1, "cpu"), 75 SUNXI_SRAM_MAP(1, 0, "de2")), 76 }; 77 78 static const struct of_device_id sunxi_sram_dt_ids[] = { 79 { 80 .compatible = "allwinner,sun4i-a10-sram-a3-a4", 81 .data = &sun4i_a10_sram_a3_a4.data, 82 }, 83 { 84 .compatible = "allwinner,sun4i-a10-sram-d", 85 .data = &sun4i_a10_sram_d.data, 86 }, 87 { 88 .compatible = "allwinner,sun50i-a64-sram-c", 89 .data = &sun50i_a64_sram_c.data, 90 }, 91 {} 92 }; 93 94 static struct device *sram_dev; 95 static LIST_HEAD(claimed_sram); 96 static DEFINE_SPINLOCK(sram_lock); 97 static void __iomem *base; 98 99 static int sunxi_sram_show(struct seq_file *s, void *data) 100 { 101 struct device_node *sram_node, *section_node; 102 const struct sunxi_sram_data *sram_data; 103 const struct of_device_id *match; 104 struct sunxi_sram_func *func; 105 const __be32 *sram_addr_p, *section_addr_p; 106 u32 val; 107 108 seq_puts(s, "Allwinner sunXi SRAM\n"); 109 seq_puts(s, "--------------------\n\n"); 110 111 for_each_child_of_node(sram_dev->of_node, sram_node) { 112 sram_addr_p = of_get_address(sram_node, 0, NULL, NULL); 113 114 seq_printf(s, "sram@%08x\n", 115 be32_to_cpu(*sram_addr_p)); 116 117 for_each_child_of_node(sram_node, section_node) { 118 match = of_match_node(sunxi_sram_dt_ids, section_node); 119 if (!match) 120 continue; 121 sram_data = match->data; 122 123 section_addr_p = of_get_address(section_node, 0, 124 NULL, NULL); 125 126 seq_printf(s, "\tsection@%04x\t(%s)\n", 127 be32_to_cpu(*section_addr_p), 128 sram_data->name); 129 130 val = readl(base + sram_data->reg); 131 val >>= sram_data->offset; 132 val &= GENMASK(sram_data->width - 1, 0); 133 134 for (func = sram_data->func; func->func; func++) { 135 seq_printf(s, "\t\t%s%c\n", func->func, 136 func->reg_val == val ? 137 '*' : ' '); 138 } 139 } 140 141 seq_puts(s, "\n"); 142 } 143 144 return 0; 145 } 146 147 static int sunxi_sram_open(struct inode *inode, struct file *file) 148 { 149 return single_open(file, sunxi_sram_show, inode->i_private); 150 } 151 152 static const struct file_operations sunxi_sram_fops = { 153 .open = sunxi_sram_open, 154 .read = seq_read, 155 .llseek = seq_lseek, 156 .release = single_release, 157 }; 158 159 static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data) 160 { 161 return container_of(data, struct sunxi_sram_desc, data); 162 } 163 164 static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node, 165 unsigned int *reg_value) 166 { 167 const struct of_device_id *match; 168 const struct sunxi_sram_data *data; 169 struct sunxi_sram_func *func; 170 struct of_phandle_args args; 171 u8 val; 172 int ret; 173 174 ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0, 175 &args); 176 if (ret) 177 return ERR_PTR(ret); 178 179 if (!of_device_is_available(args.np)) { 180 ret = -EBUSY; 181 goto err; 182 } 183 184 val = args.args[0]; 185 186 match = of_match_node(sunxi_sram_dt_ids, args.np); 187 if (!match) { 188 ret = -EINVAL; 189 goto err; 190 } 191 192 data = match->data; 193 if (!data) { 194 ret = -EINVAL; 195 goto err; 196 }; 197 198 for (func = data->func; func->func; func++) { 199 if (val == func->val) { 200 if (reg_value) 201 *reg_value = func->reg_val; 202 203 break; 204 } 205 } 206 207 if (!func->func) { 208 ret = -EINVAL; 209 goto err; 210 } 211 212 of_node_put(args.np); 213 return match->data; 214 215 err: 216 of_node_put(args.np); 217 return ERR_PTR(ret); 218 } 219 220 int sunxi_sram_claim(struct device *dev) 221 { 222 const struct sunxi_sram_data *sram_data; 223 struct sunxi_sram_desc *sram_desc; 224 unsigned int device; 225 u32 val, mask; 226 227 if (IS_ERR(base)) 228 return PTR_ERR(base); 229 230 if (!base) 231 return -EPROBE_DEFER; 232 233 if (!dev || !dev->of_node) 234 return -EINVAL; 235 236 sram_data = sunxi_sram_of_parse(dev->of_node, &device); 237 if (IS_ERR(sram_data)) 238 return PTR_ERR(sram_data); 239 240 sram_desc = to_sram_desc(sram_data); 241 242 spin_lock(&sram_lock); 243 244 if (sram_desc->claimed) { 245 spin_unlock(&sram_lock); 246 return -EBUSY; 247 } 248 249 mask = GENMASK(sram_data->offset + sram_data->width - 1, 250 sram_data->offset); 251 val = readl(base + sram_data->reg); 252 val &= ~mask; 253 writel(val | ((device << sram_data->offset) & mask), 254 base + sram_data->reg); 255 256 spin_unlock(&sram_lock); 257 258 return 0; 259 } 260 EXPORT_SYMBOL(sunxi_sram_claim); 261 262 int sunxi_sram_release(struct device *dev) 263 { 264 const struct sunxi_sram_data *sram_data; 265 struct sunxi_sram_desc *sram_desc; 266 267 if (!dev || !dev->of_node) 268 return -EINVAL; 269 270 sram_data = sunxi_sram_of_parse(dev->of_node, NULL); 271 if (IS_ERR(sram_data)) 272 return -EINVAL; 273 274 sram_desc = to_sram_desc(sram_data); 275 276 spin_lock(&sram_lock); 277 sram_desc->claimed = false; 278 spin_unlock(&sram_lock); 279 280 return 0; 281 } 282 EXPORT_SYMBOL(sunxi_sram_release); 283 284 static int sunxi_sram_probe(struct platform_device *pdev) 285 { 286 struct resource *res; 287 struct dentry *d; 288 289 sram_dev = &pdev->dev; 290 291 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 292 base = devm_ioremap_resource(&pdev->dev, res); 293 if (IS_ERR(base)) 294 return PTR_ERR(base); 295 296 of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); 297 298 d = debugfs_create_file("sram", S_IRUGO, NULL, NULL, 299 &sunxi_sram_fops); 300 if (!d) 301 return -ENOMEM; 302 303 return 0; 304 } 305 306 static const struct of_device_id sunxi_sram_dt_match[] = { 307 { .compatible = "allwinner,sun4i-a10-sram-controller" }, 308 { .compatible = "allwinner,sun50i-a64-sram-controller" }, 309 { }, 310 }; 311 MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match); 312 313 static struct platform_driver sunxi_sram_driver = { 314 .driver = { 315 .name = "sunxi-sram", 316 .of_match_table = sunxi_sram_dt_match, 317 }, 318 .probe = sunxi_sram_probe, 319 }; 320 module_platform_driver(sunxi_sram_driver); 321 322 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); 323 MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver"); 324 MODULE_LICENSE("GPL"); 325