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(0, 1, "cpu"),
  82                                   SUNXI_SRAM_MAP(1, 0, "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         spin_unlock(&sram_lock);
 258
 259         return 0;
 260 }
 261 EXPORT_SYMBOL(sunxi_sram_claim);
 262
 263 int sunxi_sram_release(struct device *dev)
 264 {
 265         const struct sunxi_sram_data *sram_data;
 266         struct sunxi_sram_desc *sram_desc;
 267
 268         if (!dev || !dev->of_node)
 269                 return -EINVAL;
 270
 271         sram_data = sunxi_sram_of_parse(dev->of_node, NULL);
 272         if (IS_ERR(sram_data))
 273                 return -EINVAL;
 274
 275         sram_desc = to_sram_desc(sram_data);
 276
 277         spin_lock(&sram_lock);
 278         sram_desc->claimed = false;
 279         spin_unlock(&sram_lock);
 280
 281         return 0;
 282 }
 283 EXPORT_SYMBOL(sunxi_sram_release);
 284
 285 struct sunxi_sramc_variant {
 286         bool has_emac_clock;
 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         .has_emac_clock = true,
 295 };
 296
 297 static const struct sunxi_sramc_variant sun50i_a64_sramc_variant = {
 298         .has_emac_clock = true,
 299 };
 300
 301 #define SUNXI_SRAM_EMAC_CLOCK_REG       0x30
 302 static bool sunxi_sram_regmap_accessible_reg(struct device *dev,
 303                                              unsigned int reg)
 304 {
 305         if (reg == SUNXI_SRAM_EMAC_CLOCK_REG)
 306                 return true;
 307         return false;
 308 }
 309
 310 static struct regmap_config sunxi_sram_emac_clock_regmap = {
 311         .reg_bits       = 32,
 312         .val_bits       = 32,
 313         .reg_stride     = 4,
 314         /* last defined register */
 315         .max_register   = SUNXI_SRAM_EMAC_CLOCK_REG,
 316         /* other devices have no business accessing other registers */
 317         .readable_reg   = sunxi_sram_regmap_accessible_reg,
 318         .writeable_reg  = sunxi_sram_regmap_accessible_reg,
 319 };
 320
 321 static int sunxi_sram_probe(struct platform_device *pdev)
 322 {
 323         struct resource *res;
 324         struct dentry *d;
 325         struct regmap *emac_clock;
 326         const struct sunxi_sramc_variant *variant;
 327
 328         sram_dev = &pdev->dev;
 329
 330         variant = of_device_get_match_data(&pdev->dev);
 331         if (!variant)
 332                 return -EINVAL;
 333
 334         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 335         base = devm_ioremap_resource(&pdev->dev, res);
 336         if (IS_ERR(base))
 337                 return PTR_ERR(base);
 338
 339         of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
 340
 341         d = debugfs_create_file("sram", S_IRUGO, NULL, NULL,
 342                                 &sunxi_sram_fops);
 343         if (!d)
 344                 return -ENOMEM;
 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         return 0;
 355 }
 356
 357 static const struct of_device_id sunxi_sram_dt_match[] = {
 358         {
 359                 .compatible = "allwinner,sun4i-a10-sram-controller",
 360                 .data = &sun4i_a10_sramc_variant,
 361         },
 362         {
 363                 .compatible = "allwinner,sun4i-a10-system-control",
 364                 .data = &sun4i_a10_sramc_variant,
 365         },
 366         {
 367                 .compatible = "allwinner,sun5i-a13-system-control",
 368                 .data = &sun4i_a10_sramc_variant,
 369         },
 370         {
 371                 .compatible = "allwinner,sun8i-a23-system-control",
 372                 .data = &sun4i_a10_sramc_variant,
 373         },
 374         {
 375                 .compatible = "allwinner,sun8i-h3-system-control",
 376                 .data = &sun8i_h3_sramc_variant,
 377         },
 378         {
 379                 .compatible = "allwinner,sun50i-a64-sram-controller",
 380                 .data = &sun50i_a64_sramc_variant,
 381         },
 382         {
 383                 .compatible = "allwinner,sun50i-a64-system-control",
 384                 .data = &sun50i_a64_sramc_variant,
 385         },
 386         {
 387                 .compatible = "allwinner,sun50i-h5-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         .probe  = sunxi_sram_probe,
 400 };
 401 module_platform_driver(sunxi_sram_driver);
 402
 403 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 404 MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");
 405 MODULE_LICENSE("GPL");