drivers/soc/sunxi/sunxi_sram.c

   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 static int sunxi_sram_open(struct inode *inode, struct file *file)
 159 {
 160         return single_open(file, sunxi_sram_show, inode->i_private);
 161 }
 162
 163 static const struct file_operations sunxi_sram_fops = {
 164         .open = sunxi_sram_open,
 165         .read = seq_read,
 166         .llseek = seq_lseek,
 167         .release = single_release,
 168 };
 169
 170 static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data)
 171 {
 172         return container_of(data, struct sunxi_sram_desc, data);
 173 }
 174
 175 static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node,
 176                                                          unsigned int *reg_value)
 177 {
 178         const struct of_device_id *match;
 179         const struct sunxi_sram_data *data;
 180         struct sunxi_sram_func *func;
 181         struct of_phandle_args args;
 182         u8 val;
 183         int ret;
 184
 185         ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0,
 186                                                &args);
 187         if (ret)
 188                 return ERR_PTR(ret);
 189
 190         if (!of_device_is_available(args.np)) {
 191                 ret = -EBUSY;
 192                 goto err;
 193         }
 194
 195         val = args.args[0];
 196
 197         match = of_match_node(sunxi_sram_dt_ids, args.np);
 198         if (!match) {
 199                 ret = -EINVAL;
 200                 goto err;
 201         }
 202
 203         data = match->data;
 204         if (!data) {
 205                 ret = -EINVAL;
 206                 goto err;
 207         };
 208
 209         for (func = data->func; func->func; func++) {
 210                 if (val == func->val) {
 211                         if (reg_value)
 212                                 *reg_value = func->reg_val;
 213
 214                         break;
 215                 }
 216         }
 217
 218         if (!func->func) {
 219                 ret = -EINVAL;
 220                 goto err;
 221         }
 222
 223         of_node_put(args.np);
 224         return match->data;
 225
 226 err:
 227         of_node_put(args.np);
 228         return ERR_PTR(ret);
 229 }
 230
 231 int sunxi_sram_claim(struct device *dev)
 232 {
 233         const struct sunxi_sram_data *sram_data;
 234         struct sunxi_sram_desc *sram_desc;
 235         unsigned int device;
 236         u32 val, mask;
 237
 238         if (IS_ERR(base))
 239                 return PTR_ERR(base);
 240
 241         if (!base)
 242                 return -EPROBE_DEFER;
 243
 244         if (!dev || !dev->of_node)
 245                 return -EINVAL;
 246
 247         sram_data = sunxi_sram_of_parse(dev->of_node, &device);
 248         if (IS_ERR(sram_data))
 249                 return PTR_ERR(sram_data);
 250
 251         sram_desc = to_sram_desc(sram_data);
 252
 253         spin_lock(&sram_lock);
 254
 255         if (sram_desc->claimed) {
 256                 spin_unlock(&sram_lock);
 257                 return -EBUSY;
 258         }
 259
 260         mask = GENMASK(sram_data->offset + sram_data->width - 1,
 261                        sram_data->offset);
 262         val = readl(base + sram_data->reg);
 263         val &= ~mask;
 264         writel(val | ((device << sram_data->offset) & mask),
 265                base + sram_data->reg);
 266
 267         sram_desc->claimed = true;
 268         spin_unlock(&sram_lock);
 269
 270         return 0;
 271 }
 272 EXPORT_SYMBOL(sunxi_sram_claim);
 273
 274 int sunxi_sram_release(struct device *dev)
 275 {
 276         const struct sunxi_sram_data *sram_data;
 277         struct sunxi_sram_desc *sram_desc;
 278
 279         if (!dev || !dev->of_node)
 280                 return -EINVAL;
 281
 282         sram_data = sunxi_sram_of_parse(dev->of_node, NULL);
 283         if (IS_ERR(sram_data))
 284                 return -EINVAL;
 285
 286         sram_desc = to_sram_desc(sram_data);
 287
 288         spin_lock(&sram_lock);
 289         sram_desc->claimed = false;
 290         spin_unlock(&sram_lock);
 291
 292         return 0;
 293 }
 294 EXPORT_SYMBOL(sunxi_sram_release);
 295
 296 struct sunxi_sramc_variant {
 297         bool has_emac_clock;
 298 };
 299
 300 static const struct sunxi_sramc_variant sun4i_a10_sramc_variant = {
 301         /* Nothing special */
 302 };
 303
 304 static const struct sunxi_sramc_variant sun50i_a64_sramc_variant = {
 305         .has_emac_clock = true,
 306 };
 307
 308 #define SUNXI_SRAM_EMAC_CLOCK_REG       0x30
 309 static bool sunxi_sram_regmap_accessible_reg(struct device *dev,
 310                                              unsigned int reg)
 311 {
 312         if (reg == SUNXI_SRAM_EMAC_CLOCK_REG)
 313                 return true;
 314         return false;
 315 }
 316
 317 static struct regmap_config sunxi_sram_emac_clock_regmap = {
 318         .reg_bits       = 32,
 319         .val_bits       = 32,
 320         .reg_stride     = 4,
 321         /* last defined register */
 322         .max_register   = SUNXI_SRAM_EMAC_CLOCK_REG,
 323         /* other devices have no business accessing other registers */
 324         .readable_reg   = sunxi_sram_regmap_accessible_reg,
 325         .writeable_reg  = sunxi_sram_regmap_accessible_reg,
 326 };
 327
 328 static int __init sunxi_sram_probe(struct platform_device *pdev)
 329 {
 330         struct resource *res;
 331         struct regmap *emac_clock;
 332         const struct sunxi_sramc_variant *variant;
 333         struct device *dev = &pdev->dev;
 334
 335         sram_dev = &pdev->dev;
 336
 337         variant = of_device_get_match_data(&pdev->dev);
 338         if (!variant)
 339                 return -EINVAL;
 340
 341         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 342         base = devm_ioremap_resource(&pdev->dev, res);
 343         if (IS_ERR(base))
 344                 return PTR_ERR(base);
 345
 346         if (variant->has_emac_clock) {
 347                 emac_clock = devm_regmap_init_mmio(&pdev->dev, base,
 348                                                    &sunxi_sram_emac_clock_regmap);
 349
 350                 if (IS_ERR(emac_clock))
 351                         return PTR_ERR(emac_clock);
 352         }
 353
 354         of_platform_populate(dev->of_node, NULL, NULL, dev);
 355
 356         debugfs_create_file("sram", 0444, NULL, NULL, &sunxi_sram_fops);
 357
 358         return 0;
 359 }
 360
 361 static const struct of_device_id sunxi_sram_dt_match[] = {
 362         {
 363                 .compatible = "allwinner,sun4i-a10-sram-controller",
 364                 .data = &sun4i_a10_sramc_variant,
 365         },
 366         {
 367                 .compatible = "allwinner,sun4i-a10-system-control",
 368                 .data = &sun4i_a10_sramc_variant,
 369         },
 370         {
 371                 .compatible = "allwinner,sun5i-a13-system-control",
 372                 .data = &sun4i_a10_sramc_variant,
 373         },
 374         {
 375                 .compatible = "allwinner,sun8i-a23-system-control",
 376                 .data = &sun4i_a10_sramc_variant,
 377         },
 378         {
 379                 .compatible = "allwinner,sun8i-h3-system-control",
 380                 .data = &sun4i_a10_sramc_variant,
 381         },
 382         {
 383                 .compatible = "allwinner,sun50i-a64-sram-controller",
 384                 .data = &sun50i_a64_sramc_variant,
 385         },
 386         {
 387                 .compatible = "allwinner,sun50i-a64-system-control",
 388                 .data = &sun50i_a64_sramc_variant,
 389         },
 390         { },
 391 };
 392 MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);
 393
 394 static struct platform_driver sunxi_sram_driver = {
 395         .driver = {
 396                 .name           = "sunxi-sram",
 397                 .of_match_table = sunxi_sram_dt_match,
 398         },
 399 };
 400 builtin_platform_driver_probe(sunxi_sram_driver, sunxi_sram_probe);
 401
 402 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 403 MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");
 404 MODULE_LICENSE("GPL");