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                 if (!of_device_is_compatible(sram_node, "mmio-sram"))
 124                         continue;
 125
 126                 sram_addr_p = of_get_address(sram_node, 0, NULL, NULL);
 127
 128                 seq_printf(s, "sram@%08x\n",
 129                            be32_to_cpu(*sram_addr_p));
 130
 131                 for_each_child_of_node(sram_node, section_node) {
 132                         match = of_match_node(sunxi_sram_dt_ids, section_node);
 133                         if (!match)
 134                                 continue;
 135                         sram_data = match->data;
 136
 137                         section_addr_p = of_get_address(section_node, 0,
 138                                                         NULL, NULL);
 139
 140                         seq_printf(s, "\tsection@%04x\t(%s)\n",
 141                                    be32_to_cpu(*section_addr_p),
 142                                    sram_data->name);
 143
 144                         val = readl(base + sram_data->reg);
 145                         val >>= sram_data->offset;
 146                         val &= GENMASK(sram_data->width - 1, 0);
 147
 148                         for (func = sram_data->func; func->func; func++) {
 149                                 seq_printf(s, "\t\t%s%c\n", func->func,
 150                                            func->reg_val == val ?
 151                                            '*' : ' ');
 152                         }
 153                 }
 154
 155                 seq_puts(s, "\n");
 156         }
 157
 158         return 0;
 159 }
 160
 161 DEFINE_SHOW_ATTRIBUTE(sunxi_sram);
 162
 163 static inline struct sunxi_sram_desc *to_sram_desc(const struct sunxi_sram_data *data)
 164 {
 165         return container_of(data, struct sunxi_sram_desc, data);
 166 }
 167
 168 static const struct sunxi_sram_data *sunxi_sram_of_parse(struct device_node *node,
 169                                                          unsigned int *reg_value)
 170 {
 171         const struct of_device_id *match;
 172         const struct sunxi_sram_data *data;
 173         struct sunxi_sram_func *func;
 174         struct of_phandle_args args;
 175         u8 val;
 176         int ret;
 177
 178         ret = of_parse_phandle_with_fixed_args(node, "allwinner,sram", 1, 0,
 179                                                &args);
 180         if (ret)
 181                 return ERR_PTR(ret);
 182
 183         if (!of_device_is_available(args.np)) {
 184                 ret = -EBUSY;
 185                 goto err;
 186         }
 187
 188         val = args.args[0];
 189
 190         match = of_match_node(sunxi_sram_dt_ids, args.np);
 191         if (!match) {
 192                 ret = -EINVAL;
 193                 goto err;
 194         }
 195
 196         data = match->data;
 197         if (!data) {
 198                 ret = -EINVAL;
 199                 goto err;
 200         }
 201
 202         for (func = data->func; func->func; func++) {
 203                 if (val == func->val) {
 204                         if (reg_value)
 205                                 *reg_value = func->reg_val;
 206
 207                         break;
 208                 }
 209         }
 210
 211         if (!func->func) {
 212                 ret = -EINVAL;
 213                 goto err;
 214         }
 215
 216         of_node_put(args.np);
 217         return match->data;
 218
 219 err:
 220         of_node_put(args.np);
 221         return ERR_PTR(ret);
 222 }
 223
 224 int sunxi_sram_claim(struct device *dev)
 225 {
 226         const struct sunxi_sram_data *sram_data;
 227         struct sunxi_sram_desc *sram_desc;
 228         unsigned int device;
 229         u32 val, mask;
 230
 231         if (IS_ERR(base))
 232                 return PTR_ERR(base);
 233
 234         if (!base)
 235                 return -EPROBE_DEFER;
 236
 237         if (!dev || !dev->of_node)
 238                 return -EINVAL;
 239
 240         sram_data = sunxi_sram_of_parse(dev->of_node, &device);
 241         if (IS_ERR(sram_data))
 242                 return PTR_ERR(sram_data);
 243
 244         sram_desc = to_sram_desc(sram_data);
 245
 246         spin_lock(&sram_lock);
 247
 248         if (sram_desc->claimed) {
 249                 spin_unlock(&sram_lock);
 250                 return -EBUSY;
 251         }
 252
 253         mask = GENMASK(sram_data->offset + sram_data->width - 1,
 254                        sram_data->offset);
 255         val = readl(base + sram_data->reg);
 256         val &= ~mask;
 257         writel(val | ((device << sram_data->offset) & mask),
 258                base + sram_data->reg);
 259
 260         sram_desc->claimed = true;
 261         spin_unlock(&sram_lock);
 262
 263         return 0;
 264 }
 265 EXPORT_SYMBOL(sunxi_sram_claim);
 266
 267 void sunxi_sram_release(struct device *dev)
 268 {
 269         const struct sunxi_sram_data *sram_data;
 270         struct sunxi_sram_desc *sram_desc;
 271
 272         if (!dev || !dev->of_node)
 273                 return;
 274
 275         sram_data = sunxi_sram_of_parse(dev->of_node, NULL);
 276         if (IS_ERR(sram_data))
 277                 return;
 278
 279         sram_desc = to_sram_desc(sram_data);
 280
 281         spin_lock(&sram_lock);
 282         sram_desc->claimed = false;
 283         spin_unlock(&sram_lock);
 284 }
 285 EXPORT_SYMBOL(sunxi_sram_release);
 286
 287 struct sunxi_sramc_variant {
 288         int num_emac_clocks;
 289         bool has_ldo_ctrl;
 290 };
 291
 292 static const struct sunxi_sramc_variant sun4i_a10_sramc_variant = {
 293         /* Nothing special */
 294 };
 295
 296 static const struct sunxi_sramc_variant sun8i_h3_sramc_variant = {
 297         .num_emac_clocks = 1,
 298 };
 299
 300 static const struct sunxi_sramc_variant sun20i_d1_sramc_variant = {
 301         .num_emac_clocks = 1,
 302         .has_ldo_ctrl = true,
 303 };
 304
 305 static const struct sunxi_sramc_variant sun50i_a64_sramc_variant = {
 306         .num_emac_clocks = 1,
 307 };
 308
 309 static const struct sunxi_sramc_variant sun50i_h616_sramc_variant = {
 310         .num_emac_clocks = 2,
 311 };
 312
 313 #define SUNXI_SRAM_EMAC_CLOCK_REG       0x30
 314 #define SUNXI_SYS_LDO_CTRL_REG          0x150
 315
 316 static bool sunxi_sram_regmap_accessible_reg(struct device *dev,
 317                                              unsigned int reg)
 318 {
 319         const struct sunxi_sramc_variant *variant = dev_get_drvdata(dev);
 320
 321         if (reg >= SUNXI_SRAM_EMAC_CLOCK_REG &&
 322             reg <  SUNXI_SRAM_EMAC_CLOCK_REG + variant->num_emac_clocks * 4)
 323                 return true;
 324         if (reg == SUNXI_SYS_LDO_CTRL_REG && variant->has_ldo_ctrl)
 325                 return true;
 326
 327         return false;
 328 }
 329
 330 static struct regmap_config sunxi_sram_regmap_config = {
 331         .reg_bits       = 32,
 332         .val_bits       = 32,
 333         .reg_stride     = 4,
 334         /* last defined register */
 335         .max_register   = SUNXI_SYS_LDO_CTRL_REG,
 336         /* other devices have no business accessing other registers */
 337         .readable_reg   = sunxi_sram_regmap_accessible_reg,
 338         .writeable_reg  = sunxi_sram_regmap_accessible_reg,
 339 };
 340
 341 static int __init sunxi_sram_probe(struct platform_device *pdev)
 342 {
 343         const struct sunxi_sramc_variant *variant;
 344         struct device *dev = &pdev->dev;
 345         struct regmap *regmap;
 346
 347         sram_dev = &pdev->dev;
 348
 349         variant = of_device_get_match_data(&pdev->dev);
 350         if (!variant)
 351                 return -EINVAL;
 352
 353         dev_set_drvdata(dev, (struct sunxi_sramc_variant *)variant);
 354
 355         base = devm_platform_ioremap_resource(pdev, 0);
 356         if (IS_ERR(base))
 357                 return PTR_ERR(base);
 358
 359         if (variant->num_emac_clocks || variant->has_ldo_ctrl) {
 360                 regmap = devm_regmap_init_mmio(dev, base, &sunxi_sram_regmap_config);
 361                 if (IS_ERR(regmap))
 362                         return PTR_ERR(regmap);
 363         }
 364
 365         of_platform_populate(dev->of_node, NULL, NULL, dev);
 366
 367         debugfs_create_file("sram", 0444, NULL, NULL, &sunxi_sram_fops);
 368
 369         return 0;
 370 }
 371
 372 static const struct of_device_id sunxi_sram_dt_match[] = {
 373         {
 374                 .compatible = "allwinner,sun4i-a10-sram-controller",
 375                 .data = &sun4i_a10_sramc_variant,
 376         },
 377         {
 378                 .compatible = "allwinner,sun4i-a10-system-control",
 379                 .data = &sun4i_a10_sramc_variant,
 380         },
 381         {
 382                 .compatible = "allwinner,sun5i-a13-system-control",
 383                 .data = &sun4i_a10_sramc_variant,
 384         },
 385         {
 386                 .compatible = "allwinner,sun8i-a23-system-control",
 387                 .data = &sun4i_a10_sramc_variant,
 388         },
 389         {
 390                 .compatible = "allwinner,sun8i-h3-system-control",
 391                 .data = &sun8i_h3_sramc_variant,
 392         },
 393         {
 394                 .compatible = "allwinner,sun20i-d1-system-control",
 395                 .data = &sun20i_d1_sramc_variant,
 396         },
 397         {
 398                 .compatible = "allwinner,sun50i-a64-sram-controller",
 399                 .data = &sun50i_a64_sramc_variant,
 400         },
 401         {
 402                 .compatible = "allwinner,sun50i-a64-system-control",
 403                 .data = &sun50i_a64_sramc_variant,
 404         },
 405         {
 406                 .compatible = "allwinner,sun50i-h5-system-control",
 407                 .data = &sun50i_a64_sramc_variant,
 408         },
 409         {
 410                 .compatible = "allwinner,sun50i-h616-system-control",
 411                 .data = &sun50i_h616_sramc_variant,
 412         },
 413         { },
 414 };
 415 MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);
 416
 417 static struct platform_driver sunxi_sram_driver = {
 418         .driver = {
 419                 .name           = "sunxi-sram",
 420                 .of_match_table = sunxi_sram_dt_match,
 421         },
 422 };
 423 builtin_platform_driver_probe(sunxi_sram_driver, sunxi_sram_probe);
 424
 425 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 426 MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");