linux/drivers/clk/samsung/clk-s3c2410-dclk.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
   4 *
   5 * Common Clock Framework support for s3c24xx external clock output.
   6 */
   7
   8#include <linux/clkdev.h>
   9#include <linux/slab.h>
  10#include <linux/clk.h>
  11#include <linux/clk-provider.h>
  12#include <linux/io.h>
  13#include <linux/platform_device.h>
  14#include <linux/module.h>
  15#include "clk.h"
  16
  17/* legacy access to misccr, until dt conversion is finished */
  18#include <mach/hardware.h>
  19#include <mach/regs-gpio.h>
  20
  21#define MUX_DCLK0       0
  22#define MUX_DCLK1       1
  23#define DIV_DCLK0       2
  24#define DIV_DCLK1       3
  25#define GATE_DCLK0      4
  26#define GATE_DCLK1      5
  27#define MUX_CLKOUT0     6
  28#define MUX_CLKOUT1     7
  29#define DCLK_MAX_CLKS   (MUX_CLKOUT1 + 1)
  30
  31enum supported_socs {
  32        S3C2410,
  33        S3C2412,
  34        S3C2440,
  35        S3C2443,
  36};
  37
  38struct s3c24xx_dclk_drv_data {
  39        const char **clkout0_parent_names;
  40        int clkout0_num_parents;
  41        const char **clkout1_parent_names;
  42        int clkout1_num_parents;
  43        const char **mux_parent_names;
  44        int mux_num_parents;
  45};
  46
  47/*
  48 * Clock for output-parent selection in misccr
  49 */
  50
  51struct s3c24xx_clkout {
  52        struct clk_hw           hw;
  53        u32                     mask;
  54        u8                      shift;
  55};
  56
  57#define to_s3c24xx_clkout(_hw) container_of(_hw, struct s3c24xx_clkout, hw)
  58
  59static u8 s3c24xx_clkout_get_parent(struct clk_hw *hw)
  60{
  61        struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
  62        int num_parents = clk_hw_get_num_parents(hw);
  63        u32 val;
  64
  65        val = readl_relaxed(S3C24XX_MISCCR) >> clkout->shift;
  66        val >>= clkout->shift;
  67        val &= clkout->mask;
  68
  69        if (val >= num_parents)
  70                return -EINVAL;
  71
  72        return val;
  73}
  74
  75static int s3c24xx_clkout_set_parent(struct clk_hw *hw, u8 index)
  76{
  77        struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
  78
  79        s3c2410_modify_misccr((clkout->mask << clkout->shift),
  80                              (index << clkout->shift));
  81
  82        return 0;
  83}
  84
  85static const struct clk_ops s3c24xx_clkout_ops = {
  86        .get_parent = s3c24xx_clkout_get_parent,
  87        .set_parent = s3c24xx_clkout_set_parent,
  88        .determine_rate = __clk_mux_determine_rate,
  89};
  90
  91static struct clk_hw *s3c24xx_register_clkout(struct device *dev,
  92                const char *name, const char **parent_names, u8 num_parents,
  93                u8 shift, u32 mask)
  94{
  95        struct s3c24xx_clkout *clkout;
  96        struct clk_init_data init;
  97        int ret;
  98
  99        /* allocate the clkout */
 100        clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
 101        if (!clkout)
 102                return ERR_PTR(-ENOMEM);
 103
 104        init.name = name;
 105        init.ops = &s3c24xx_clkout_ops;
 106        init.flags = 0;
 107        init.parent_names = parent_names;
 108        init.num_parents = num_parents;
 109
 110        clkout->shift = shift;
 111        clkout->mask = mask;
 112        clkout->hw.init = &init;
 113
 114        ret = clk_hw_register(dev, &clkout->hw);
 115        if (ret)
 116                return ERR_PTR(ret);
 117
 118        return &clkout->hw;
 119}
 120
 121/*
 122 * dclk and clkout init
 123 */
 124
 125struct s3c24xx_dclk {
 126        struct device *dev;
 127        void __iomem *base;
 128        struct notifier_block dclk0_div_change_nb;
 129        struct notifier_block dclk1_div_change_nb;
 130        spinlock_t dclk_lock;
 131        unsigned long reg_save;
 132        /* clk_data must be the last entry in the structure */
 133        struct clk_hw_onecell_data clk_data;
 134};
 135
 136#define to_s3c24xx_dclk0(x) \
 137                container_of(x, struct s3c24xx_dclk, dclk0_div_change_nb)
 138
 139#define to_s3c24xx_dclk1(x) \
 140                container_of(x, struct s3c24xx_dclk, dclk1_div_change_nb)
 141
 142static const char *dclk_s3c2410_p[] = { "pclk", "uclk" };
 143static const char *clkout0_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 144                             "gate_dclk0" };
 145static const char *clkout1_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 146                             "gate_dclk1" };
 147
 148static const char *clkout0_s3c2412_p[] = { "mpll", "upll", "rtc_clkout",
 149                             "hclk", "pclk", "gate_dclk0" };
 150static const char *clkout1_s3c2412_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 151                             "gate_dclk1" };
 152
 153static const char *clkout0_s3c2440_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 154                             "gate_dclk0" };
 155static const char *clkout1_s3c2440_p[] = { "mpll", "upll", "rtc_clkout",
 156                             "hclk", "pclk", "gate_dclk1" };
 157
 158static const char *dclk_s3c2443_p[] = { "pclk", "epll" };
 159static const char *clkout0_s3c2443_p[] = { "xti", "epll", "armclk", "hclk", "pclk",
 160                             "gate_dclk0" };
 161static const char *clkout1_s3c2443_p[] = { "dummy", "epll", "rtc_clkout",
 162                             "hclk", "pclk", "gate_dclk1" };
 163
 164#define DCLKCON_DCLK_DIV_MASK           0xf
 165#define DCLKCON_DCLK0_DIV_SHIFT         4
 166#define DCLKCON_DCLK0_CMP_SHIFT         8
 167#define DCLKCON_DCLK1_DIV_SHIFT         20
 168#define DCLKCON_DCLK1_CMP_SHIFT         24
 169
 170static void s3c24xx_dclk_update_cmp(struct s3c24xx_dclk *s3c24xx_dclk,
 171                                    int div_shift, int cmp_shift)
 172{
 173        unsigned long flags = 0;
 174        u32 dclk_con, div, cmp;
 175
 176        spin_lock_irqsave(&s3c24xx_dclk->dclk_lock, flags);
 177
 178        dclk_con = readl_relaxed(s3c24xx_dclk->base);
 179
 180        div = ((dclk_con >> div_shift) & DCLKCON_DCLK_DIV_MASK) + 1;
 181        cmp = ((div + 1) / 2) - 1;
 182
 183        dclk_con &= ~(DCLKCON_DCLK_DIV_MASK << cmp_shift);
 184        dclk_con |= (cmp << cmp_shift);
 185
 186        writel_relaxed(dclk_con, s3c24xx_dclk->base);
 187
 188        spin_unlock_irqrestore(&s3c24xx_dclk->dclk_lock, flags);
 189}
 190
 191static int s3c24xx_dclk0_div_notify(struct notifier_block *nb,
 192                               unsigned long event, void *data)
 193{
 194        struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk0(nb);
 195
 196        if (event == POST_RATE_CHANGE) {
 197                s3c24xx_dclk_update_cmp(s3c24xx_dclk,
 198                        DCLKCON_DCLK0_DIV_SHIFT, DCLKCON_DCLK0_CMP_SHIFT);
 199        }
 200
 201        return NOTIFY_DONE;
 202}
 203
 204static int s3c24xx_dclk1_div_notify(struct notifier_block *nb,
 205                               unsigned long event, void *data)
 206{
 207        struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk1(nb);
 208
 209        if (event == POST_RATE_CHANGE) {
 210                s3c24xx_dclk_update_cmp(s3c24xx_dclk,
 211                        DCLKCON_DCLK1_DIV_SHIFT, DCLKCON_DCLK1_CMP_SHIFT);
 212        }
 213
 214        return NOTIFY_DONE;
 215}
 216
 217#ifdef CONFIG_PM_SLEEP
 218static int s3c24xx_dclk_suspend(struct device *dev)
 219{
 220        struct s3c24xx_dclk *s3c24xx_dclk = dev_get_drvdata(dev);
 221
 222        s3c24xx_dclk->reg_save = readl_relaxed(s3c24xx_dclk->base);
 223        return 0;
 224}
 225
 226static int s3c24xx_dclk_resume(struct device *dev)
 227{
 228        struct s3c24xx_dclk *s3c24xx_dclk = dev_get_drvdata(dev);
 229
 230        writel_relaxed(s3c24xx_dclk->reg_save, s3c24xx_dclk->base);
 231        return 0;
 232}
 233#endif
 234
 235static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
 236                         s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
 237
 238static int s3c24xx_dclk_probe(struct platform_device *pdev)
 239{
 240        struct s3c24xx_dclk *s3c24xx_dclk;
 241        struct resource *mem;
 242        struct s3c24xx_dclk_drv_data *dclk_variant;
 243        struct clk_hw **clk_table;
 244        int ret, i;
 245
 246        s3c24xx_dclk = devm_kzalloc(&pdev->dev,
 247                                    struct_size(s3c24xx_dclk, clk_data.hws,
 248                                                DCLK_MAX_CLKS),
 249                                    GFP_KERNEL);
 250        if (!s3c24xx_dclk)
 251                return -ENOMEM;
 252
 253        clk_table = s3c24xx_dclk->clk_data.hws;
 254
 255        s3c24xx_dclk->dev = &pdev->dev;
 256        s3c24xx_dclk->clk_data.num = DCLK_MAX_CLKS;
 257        platform_set_drvdata(pdev, s3c24xx_dclk);
 258        spin_lock_init(&s3c24xx_dclk->dclk_lock);
 259
 260        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 261        s3c24xx_dclk->base = devm_ioremap_resource(&pdev->dev, mem);
 262        if (IS_ERR(s3c24xx_dclk->base))
 263                return PTR_ERR(s3c24xx_dclk->base);
 264
 265        dclk_variant = (struct s3c24xx_dclk_drv_data *)
 266                                platform_get_device_id(pdev)->driver_data;
 267
 268
 269        clk_table[MUX_DCLK0] = clk_hw_register_mux(&pdev->dev, "mux_dclk0",
 270                                dclk_variant->mux_parent_names,
 271                                dclk_variant->mux_num_parents, 0,
 272                                s3c24xx_dclk->base, 1, 1, 0,
 273                                &s3c24xx_dclk->dclk_lock);
 274        clk_table[MUX_DCLK1] = clk_hw_register_mux(&pdev->dev, "mux_dclk1",
 275                                dclk_variant->mux_parent_names,
 276                                dclk_variant->mux_num_parents, 0,
 277                                s3c24xx_dclk->base, 17, 1, 0,
 278                                &s3c24xx_dclk->dclk_lock);
 279
 280        clk_table[DIV_DCLK0] = clk_hw_register_divider(&pdev->dev, "div_dclk0",
 281                                "mux_dclk0", 0, s3c24xx_dclk->base,
 282                                4, 4, 0, &s3c24xx_dclk->dclk_lock);
 283        clk_table[DIV_DCLK1] = clk_hw_register_divider(&pdev->dev, "div_dclk1",
 284                                "mux_dclk1", 0, s3c24xx_dclk->base,
 285                                20, 4, 0, &s3c24xx_dclk->dclk_lock);
 286
 287        clk_table[GATE_DCLK0] = clk_hw_register_gate(&pdev->dev, "gate_dclk0",
 288                                "div_dclk0", CLK_SET_RATE_PARENT,
 289                                s3c24xx_dclk->base, 0, 0,
 290                                &s3c24xx_dclk->dclk_lock);
 291        clk_table[GATE_DCLK1] = clk_hw_register_gate(&pdev->dev, "gate_dclk1",
 292                                "div_dclk1", CLK_SET_RATE_PARENT,
 293                                s3c24xx_dclk->base, 16, 0,
 294                                &s3c24xx_dclk->dclk_lock);
 295
 296        clk_table[MUX_CLKOUT0] = s3c24xx_register_clkout(&pdev->dev,
 297                                "clkout0", dclk_variant->clkout0_parent_names,
 298                                dclk_variant->clkout0_num_parents, 4, 7);
 299        clk_table[MUX_CLKOUT1] = s3c24xx_register_clkout(&pdev->dev,
 300                                "clkout1", dclk_variant->clkout1_parent_names,
 301                                dclk_variant->clkout1_num_parents, 8, 7);
 302
 303        for (i = 0; i < DCLK_MAX_CLKS; i++)
 304                if (IS_ERR(clk_table[i])) {
 305                        dev_err(&pdev->dev, "clock %d failed to register\n", i);
 306                        ret = PTR_ERR(clk_table[i]);
 307                        goto err_clk_register;
 308                }
 309
 310        ret = clk_hw_register_clkdev(clk_table[MUX_DCLK0], "dclk0", NULL);
 311        if (!ret)
 312                ret = clk_hw_register_clkdev(clk_table[MUX_DCLK1], "dclk1",
 313                                             NULL);
 314        if (!ret)
 315                ret = clk_hw_register_clkdev(clk_table[MUX_CLKOUT0],
 316                                             "clkout0", NULL);
 317        if (!ret)
 318                ret = clk_hw_register_clkdev(clk_table[MUX_CLKOUT1],
 319                                             "clkout1", NULL);
 320        if (ret) {
 321                dev_err(&pdev->dev, "failed to register aliases, %d\n", ret);
 322                goto err_clk_register;
 323        }
 324
 325        s3c24xx_dclk->dclk0_div_change_nb.notifier_call =
 326                                                s3c24xx_dclk0_div_notify;
 327
 328        s3c24xx_dclk->dclk1_div_change_nb.notifier_call =
 329                                                s3c24xx_dclk1_div_notify;
 330
 331        ret = clk_notifier_register(clk_table[DIV_DCLK0]->clk,
 332                                    &s3c24xx_dclk->dclk0_div_change_nb);
 333        if (ret)
 334                goto err_clk_register;
 335
 336        ret = clk_notifier_register(clk_table[DIV_DCLK1]->clk,
 337                                    &s3c24xx_dclk->dclk1_div_change_nb);
 338        if (ret)
 339                goto err_dclk_notify;
 340
 341        return 0;
 342
 343err_dclk_notify:
 344        clk_notifier_unregister(clk_table[DIV_DCLK0]->clk,
 345                                &s3c24xx_dclk->dclk0_div_change_nb);
 346err_clk_register:
 347        for (i = 0; i < DCLK_MAX_CLKS; i++)
 348                if (clk_table[i] && !IS_ERR(clk_table[i]))
 349                        clk_hw_unregister(clk_table[i]);
 350
 351        return ret;
 352}
 353
 354static int s3c24xx_dclk_remove(struct platform_device *pdev)
 355{
 356        struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 357        struct clk_hw **clk_table = s3c24xx_dclk->clk_data.hws;
 358        int i;
 359
 360        clk_notifier_unregister(clk_table[DIV_DCLK1]->clk,
 361                                &s3c24xx_dclk->dclk1_div_change_nb);
 362        clk_notifier_unregister(clk_table[DIV_DCLK0]->clk,
 363                                &s3c24xx_dclk->dclk0_div_change_nb);
 364
 365        for (i = 0; i < DCLK_MAX_CLKS; i++)
 366                clk_hw_unregister(clk_table[i]);
 367
 368        return 0;
 369}
 370
 371static struct s3c24xx_dclk_drv_data dclk_variants[] = {
 372        [S3C2410] = {
 373                .clkout0_parent_names = clkout0_s3c2410_p,
 374                .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2410_p),
 375                .clkout1_parent_names = clkout1_s3c2410_p,
 376                .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2410_p),
 377                .mux_parent_names = dclk_s3c2410_p,
 378                .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 379        },
 380        [S3C2412] = {
 381                .clkout0_parent_names = clkout0_s3c2412_p,
 382                .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2412_p),
 383                .clkout1_parent_names = clkout1_s3c2412_p,
 384                .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2412_p),
 385                .mux_parent_names = dclk_s3c2410_p,
 386                .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 387        },
 388        [S3C2440] = {
 389                .clkout0_parent_names = clkout0_s3c2440_p,
 390                .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2440_p),
 391                .clkout1_parent_names = clkout1_s3c2440_p,
 392                .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2440_p),
 393                .mux_parent_names = dclk_s3c2410_p,
 394                .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 395        },
 396        [S3C2443] = {
 397                .clkout0_parent_names = clkout0_s3c2443_p,
 398                .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2443_p),
 399                .clkout1_parent_names = clkout1_s3c2443_p,
 400                .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2443_p),
 401                .mux_parent_names = dclk_s3c2443_p,
 402                .mux_num_parents = ARRAY_SIZE(dclk_s3c2443_p),
 403        },
 404};
 405
 406static const struct platform_device_id s3c24xx_dclk_driver_ids[] = {
 407        {
 408                .name           = "s3c2410-dclk",
 409                .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2410],
 410        }, {
 411                .name           = "s3c2412-dclk",
 412                .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2412],
 413        }, {
 414                .name           = "s3c2440-dclk",
 415                .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2440],
 416        }, {
 417                .name           = "s3c2443-dclk",
 418                .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2443],
 419        },
 420        { }
 421};
 422
 423MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
 424
 425static struct platform_driver s3c24xx_dclk_driver = {
 426        .driver = {
 427                .name                   = "s3c24xx-dclk",
 428                .pm                     = &s3c24xx_dclk_pm_ops,
 429                .suppress_bind_attrs    = true,
 430        },
 431        .probe = s3c24xx_dclk_probe,
 432        .remove = s3c24xx_dclk_remove,
 433        .id_table = s3c24xx_dclk_driver_ids,
 434};
 435module_platform_driver(s3c24xx_dclk_driver);
 436
 437MODULE_LICENSE("GPL v2");
 438MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 439MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");
 440