linux/drivers/soc/sunxi/sunxi_sram.c
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   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
  24struct sunxi_sram_func {
  25        char    *func;
  26        u8      val;
  27        u32     reg_val;
  28};
  29
  30struct 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
  39struct 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
  61static 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
  67static 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
  73static 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
  79static 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
  85static 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
 105static struct device *sram_dev;
 106static LIST_HEAD(claimed_sram);
 107static DEFINE_SPINLOCK(sram_lock);
 108static void __iomem *base;
 109
 110static 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
 158DEFINE_SHOW_ATTRIBUTE(sunxi_sram);
 159
 160static 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
 165static 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
 216err:
 217        of_node_put(args.np);
 218        return ERR_PTR(ret);
 219}
 220
 221int 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}
 261EXPORT_SYMBOL(sunxi_sram_claim);
 262
 263int 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}
 283EXPORT_SYMBOL(sunxi_sram_release);
 284
 285struct sunxi_sramc_variant {
 286        int num_emac_clocks;
 287};
 288
 289static const struct sunxi_sramc_variant sun4i_a10_sramc_variant = {
 290        /* Nothing special */
 291};
 292
 293static const struct sunxi_sramc_variant sun8i_h3_sramc_variant = {
 294        .num_emac_clocks = 1,
 295};
 296
 297static const struct sunxi_sramc_variant sun50i_a64_sramc_variant = {
 298        .num_emac_clocks = 1,
 299};
 300
 301static const struct sunxi_sramc_variant sun50i_h616_sramc_variant = {
 302        .num_emac_clocks = 2,
 303};
 304
 305#define SUNXI_SRAM_EMAC_CLOCK_REG       0x30
 306static bool sunxi_sram_regmap_accessible_reg(struct device *dev,
 307                                             unsigned int reg)
 308{
 309        const struct sunxi_sramc_variant *variant;
 310
 311        variant = of_device_get_match_data(dev);
 312
 313        if (reg < SUNXI_SRAM_EMAC_CLOCK_REG)
 314                return false;
 315        if (reg > SUNXI_SRAM_EMAC_CLOCK_REG + variant->num_emac_clocks * 4)
 316                return false;
 317
 318        return true;
 319}
 320
 321static struct regmap_config sunxi_sram_emac_clock_regmap = {
 322        .reg_bits       = 32,
 323        .val_bits       = 32,
 324        .reg_stride     = 4,
 325        /* last defined register */
 326        .max_register   = SUNXI_SRAM_EMAC_CLOCK_REG + 4,
 327        /* other devices have no business accessing other registers */
 328        .readable_reg   = sunxi_sram_regmap_accessible_reg,
 329        .writeable_reg  = sunxi_sram_regmap_accessible_reg,
 330};
 331
 332static int sunxi_sram_probe(struct platform_device *pdev)
 333{
 334        struct resource *res;
 335        struct dentry *d;
 336        struct regmap *emac_clock;
 337        const struct sunxi_sramc_variant *variant;
 338
 339        sram_dev = &pdev->dev;
 340
 341        variant = of_device_get_match_data(&pdev->dev);
 342        if (!variant)
 343                return -EINVAL;
 344
 345        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 346        base = devm_ioremap_resource(&pdev->dev, res);
 347        if (IS_ERR(base))
 348                return PTR_ERR(base);
 349
 350        of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
 351
 352        d = debugfs_create_file("sram", S_IRUGO, NULL, NULL,
 353                                &sunxi_sram_fops);
 354        if (!d)
 355                return -ENOMEM;
 356
 357        if (variant->num_emac_clocks > 0) {
 358                emac_clock = devm_regmap_init_mmio(&pdev->dev, base,
 359                                                   &sunxi_sram_emac_clock_regmap);
 360
 361                if (IS_ERR(emac_clock))
 362                        return PTR_ERR(emac_clock);
 363        }
 364
 365        return 0;
 366}
 367
 368static const struct of_device_id sunxi_sram_dt_match[] = {
 369        {
 370                .compatible = "allwinner,sun4i-a10-sram-controller",
 371                .data = &sun4i_a10_sramc_variant,
 372        },
 373        {
 374                .compatible = "allwinner,sun4i-a10-system-control",
 375                .data = &sun4i_a10_sramc_variant,
 376        },
 377        {
 378                .compatible = "allwinner,sun5i-a13-system-control",
 379                .data = &sun4i_a10_sramc_variant,
 380        },
 381        {
 382                .compatible = "allwinner,sun8i-a23-system-control",
 383                .data = &sun4i_a10_sramc_variant,
 384        },
 385        {
 386                .compatible = "allwinner,sun8i-h3-system-control",
 387                .data = &sun8i_h3_sramc_variant,
 388        },
 389        {
 390                .compatible = "allwinner,sun50i-a64-sram-controller",
 391                .data = &sun50i_a64_sramc_variant,
 392        },
 393        {
 394                .compatible = "allwinner,sun50i-a64-system-control",
 395                .data = &sun50i_a64_sramc_variant,
 396        },
 397        {
 398                .compatible = "allwinner,sun50i-h5-system-control",
 399                .data = &sun50i_a64_sramc_variant,
 400        },
 401        {
 402                .compatible = "allwinner,sun50i-h616-system-control",
 403                .data = &sun50i_h616_sramc_variant,
 404        },
 405        { },
 406};
 407MODULE_DEVICE_TABLE(of, sunxi_sram_dt_match);
 408
 409static struct platform_driver sunxi_sram_driver = {
 410        .driver = {
 411                .name           = "sunxi-sram",
 412                .of_match_table = sunxi_sram_dt_match,
 413        },
 414        .probe  = sunxi_sram_probe,
 415};
 416module_platform_driver(sunxi_sram_driver);
 417
 418MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 419MODULE_DESCRIPTION("Allwinner sunXi SRAM Controller Driver");
 420MODULE_LICENSE("GPL");
 421
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