// SPDX-License-Identifier: GPL-2.0
/*
 * Renesas Clock Pulse Generator / Module Standby and Software Reset
 *
 * Copyright (C) 2015 Glider bvba
 *
 * Based on clk-mstp.c, clk-rcar-gen2.c, and clk-rcar-gen3.c
 *
 * Copyright (C) 2013 Ideas On Board SPRL
 * Copyright (C) 2015 Renesas Electronics Corp.
 */

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clk/renesas.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_clock.h>
#include <linux/pm_domain.h>
#include <linux/psci.h>
#include <linux/reset-controller.h>
#include <linux/slab.h>

#include <dt-bindings/clock/renesas-cpg-mssr.h>

#include "renesas-cpg-mssr.h"
#include "clk-div6.h"

#ifdef DEBUG
#define WARN_DEBUG(x)   WARN_ON(x)
#else
#define WARN_DEBUG(x)   do { } while (0)
#endif


/*
 * Module Standby and Software Reset register offets.
 *
 * If the registers exist, these are valid for SH-Mobile, R-Mobile,
 * R-Car Gen2, R-Car Gen3, and RZ/G1.
 * These are NOT valid for R-Car Gen1 and RZ/A1!
 */

/*
 * Module Stop Status Register offsets
 */

static const u16 mstpsr[] = {
        0x030, 0x038, 0x040, 0x048, 0x04C, 0x03C, 0x1C0, 0x1C4,
        0x9A0, 0x9A4, 0x9A8, 0x9AC,
};

#define MSTPSR(i)       mstpsr[i]


/*
 * System Module Stop Control Register offsets
 */

static const u16 smstpcr[] = {
        0x130, 0x134, 0x138, 0x13C, 0x140, 0x144, 0x148, 0x14C,
        0x990, 0x994, 0x998, 0x99C,
};

#define SMSTPCR(i)      smstpcr[i]

/*
 * Standby Control Register offsets (RZ/A)
 * Base address is FRQCR register
 */

static const u16 stbcr[] = {
        0xFFFF/*dummy*/, 0x010, 0x014, 0x410, 0x414, 0x418, 0x41C, 0x420,
        0x424, 0x428, 0x42C,
};

#define STBCR(i)        stbcr[i]

/*
 * Software Reset Register offsets
 */

static const u16 srcr[] = {
        0x0A0, 0x0A8, 0x0B0, 0x0B8, 0x0BC, 0x0C4, 0x1C8, 0x1CC,
        0x920, 0x924, 0x928, 0x92C,
};

#define SRCR(i)         srcr[i]


/* Realtime Module Stop Control Register offsets */
#define RMSTPCR(i)      (smstpcr[i] - 0x20)

/* Modem Module Stop Control Register offsets (r8a73a4) */
#define MMSTPCR(i)      (smstpcr[i] + 0x20)

/* Software Reset Clearing Register offsets */
#define SRSTCLR(i)      (0x940 + (i) * 4)


/**
 * Clock Pulse Generator / Module Standby and Software Reset Private Data
 *
 * @rcdev: Optional reset controller entity
 * @dev: CPG/MSSR device
 * @base: CPG/MSSR register block base address
 * @rmw_lock: protects RMW register accesses
 * @np: Device node in DT for this CPG/MSSR module
 * @num_core_clks: Number of Core Clocks in clks[]
 * @num_mod_clks: Number of Module Clocks in clks[]
 * @last_dt_core_clk: ID of the last Core Clock exported to DT
 * @stbyctrl: This device has Standby Control Registers
 * @notifiers: Notifier chain to save/restore clock state for system resume
 * @smstpcr_saved[].mask: Mask of SMSTPCR[] bits under our control
 * @smstpcr_saved[].val: Saved values of SMSTPCR[]
 * @clks: Array containing all Core and Module Clocks
 */
struct cpg_mssr_priv {
#ifdef CONFIG_RESET_CONTROLLER
        struct reset_controller_dev rcdev;
#endif
        struct device *dev;
        void __iomem *base;
        spinlock_t rmw_lock;
        struct device_node *np;

        unsigned int num_core_clks;
        unsigned int num_mod_clks;
        unsigned int last_dt_core_clk;
        bool stbyctrl;

        struct raw_notifier_head notifiers;
        struct {
                u32 mask;
                u32 val;
        } smstpcr_saved[ARRAY_SIZE(smstpcr)];

        struct clk *clks[];
};

static struct cpg_mssr_priv *cpg_mssr_priv;

/**
 * struct mstp_clock - MSTP gating clock
 * @hw: handle between common and hardware-specific interfaces
 * @index: MSTP clock number
 * @priv: CPG/MSSR private data
 */
struct mstp_clock {
        struct clk_hw hw;
        u32 index;
        struct cpg_mssr_priv *priv;
};

#define to_mstp_clock(_hw) container_of(_hw, struct mstp_clock, hw)

static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
{
        struct mstp_clock *clock = to_mstp_clock(hw);
        struct cpg_mssr_priv *priv = clock->priv;
        unsigned int reg = clock->index / 32;
        unsigned int bit = clock->index % 32;
        struct device *dev = priv->dev;
        u32 bitmask = BIT(bit);
        unsigned long flags;
        unsigned int i;
        u32 value;

        dev_dbg(dev, "MSTP %u%02u/%pC %s\n", reg, bit, hw->clk,
                enable ? "ON" : "OFF");
        spin_lock_irqsave(&priv->rmw_lock, flags);

        if (priv->stbyctrl) {
                value = readb(priv->base + STBCR(reg));
                if (enable)
                        value &= ~bitmask;
                else
                        value |= bitmask;
                writeb(value, priv->base + STBCR(reg));

                /* dummy read to ensure write has completed */
                readb(priv->base + STBCR(reg));
                barrier_data(priv->base + STBCR(reg));
        } else {
                value = readl(priv->base + SMSTPCR(reg));
                if (enable)
                        value &= ~bitmask;
                else
                        value |= bitmask;
                writel(value, priv->base + SMSTPCR(reg));
        }

        spin_unlock_irqrestore(&priv->rmw_lock, flags);

        if (!enable || priv->stbyctrl)
                return 0;

        for (i = 1000; i > 0; --i) {
                if (!(readl(priv->base + MSTPSR(reg)) & bitmask))
                        break;
                cpu_relax();
        }

        if (!i) {
                dev_err(dev, "Failed to enable SMSTP %p[%d]\n",
                        priv->base + SMSTPCR(reg), bit);
                return -ETIMEDOUT;
        }

        return 0;
}

static int cpg_mstp_clock_enable(struct clk_hw *hw)
{
        return cpg_mstp_clock_endisable(hw, true);
}

static void cpg_mstp_clock_disable(struct clk_hw *hw)
{
        cpg_mstp_clock_endisable(hw, false);
}

static int cpg_mstp_clock_is_enabled(struct clk_hw *hw)
{
        struct mstp_clock *clock = to_mstp_clock(hw);
        struct cpg_mssr_priv *priv = clock->priv;
        u32 value;

        if (priv->stbyctrl)
                value = readb(priv->base + STBCR(clock->index / 32));
        else
                value = readl(priv->base + MSTPSR(clock->index / 32));

        return !(value & BIT(clock->index % 32));
}

static const struct clk_ops cpg_mstp_clock_ops = {
        .enable = cpg_mstp_clock_enable,
        .disable = cpg_mstp_clock_disable,
        .is_enabled = cpg_mstp_clock_is_enabled,
};

static
struct clk *cpg_mssr_clk_src_twocell_get(struct of_phandle_args *clkspec,
                                         void *data)
{
        unsigned int clkidx = clkspec->args[1];
        struct cpg_mssr_priv *priv = data;
        struct device *dev = priv->dev;
        unsigned int idx;
        const char *type;
        struct clk *clk;
        int range_check;

        switch (clkspec->args[0]) {
        case CPG_CORE:
                type = "core";
                if (clkidx > priv->last_dt_core_clk) {
                        dev_err(dev, "Invalid %s clock index %u\n", type,
                               clkidx);
                        return ERR_PTR(-EINVAL);
                }
                clk = priv->clks[clkidx];
                break;

        case CPG_MOD:
                type = "module";
                if (priv->stbyctrl) {
                        idx = MOD_CLK_PACK_10(clkidx);
                        range_check = 7 - (clkidx % 10);
                } else {
                        idx = MOD_CLK_PACK(clkidx);
                        range_check = 31 - (clkidx % 100);
                }
                if (range_check < 0 || idx >= priv->num_mod_clks) {
                        dev_err(dev, "Invalid %s clock index %u\n", type,
                                clkidx);
                        return ERR_PTR(-EINVAL);
                }
                clk = priv->clks[priv->num_core_clks + idx];
                break;

        default:
                dev_err(dev, "Invalid CPG clock type %u\n", clkspec->args[0]);
                return ERR_PTR(-EINVAL);
        }

        if (IS_ERR(clk))
                dev_err(dev, "Cannot get %s clock %u: %ld", type, clkidx,
                       PTR_ERR(clk));
        else
                dev_dbg(dev, "clock (%u, %u) is %pC at %lu Hz\n",
                        clkspec->args[0], clkspec->args[1], clk,
                        clk_get_rate(clk));
        return clk;
}

static void __init cpg_mssr_register_core_clk(const struct cpg_core_clk *core,
                                              const struct cpg_mssr_info *info,
                                              struct cpg_mssr_priv *priv)
{
        struct clk *clk = ERR_PTR(-ENOTSUPP), *parent;
        struct device *dev = priv->dev;
        unsigned int id = core->id, div = core->div;
        const char *parent_name;

        WARN_DEBUG(id >= priv->num_core_clks);
        WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);

        if (!core->name) {
                /* Skip NULLified clock */
                return;
        }

        switch (core->type) {
        case CLK_TYPE_IN:
                clk = of_clk_get_by_name(priv->np, core->name);
                break;

        case CLK_TYPE_FF:
        case CLK_TYPE_DIV6P1:
        case CLK_TYPE_DIV6_RO:
                WARN_DEBUG(core->parent >= priv->num_core_clks);
                parent = priv->clks[core->parent];
                if (IS_ERR(parent)) {
                        clk = parent;
                        goto fail;
                }

                parent_name = __clk_get_name(parent);

                if (core->type == CLK_TYPE_DIV6_RO)
                        /* Multiply with the DIV6 register value */
                        div *= (readl(priv->base + core->offset) & 0x3f) + 1;

                if (core->type == CLK_TYPE_DIV6P1) {
                        clk = cpg_div6_register(core->name, 1, &parent_name,
                                                priv->base + core->offset,
                                                &priv->notifiers);
                } else {
                        clk = clk_register_fixed_factor(NULL, core->name,
                                                        parent_name, 0,
                                                        core->mult, div);
                }
                break;

        case CLK_TYPE_FR:
                clk = clk_register_fixed_rate(NULL, core->name, NULL, 0,
                                              core->mult);
                break;

        default:
                if (info->cpg_clk_register)
                        clk = info->cpg_clk_register(dev, core, info,
                                                     priv->clks, priv->base,
                                                     &priv->notifiers);
                else
                        dev_err(dev, "%s has unsupported core clock type %u\n",
                                core->name, core->type);
                break;
        }

        if (IS_ERR_OR_NULL(clk))
                goto fail;

        dev_dbg(dev, "Core clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
        priv->clks[id] = clk;
        return;

fail:
        dev_err(dev, "Failed to register %s clock %s: %ld\n", "core",
                core->name, PTR_ERR(clk));
}

static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
                                             const struct cpg_mssr_info *info,
                                             struct cpg_mssr_priv *priv)
{
        struct mstp_clock *clock = NULL;
        struct device *dev = priv->dev;
        unsigned int id = mod->id;
        struct clk_init_data init;
        struct clk *parent, *clk;
        const char *parent_name;
        unsigned int i;

        WARN_DEBUG(id < priv->num_core_clks);
        WARN_DEBUG(id >= priv->num_core_clks + priv->num_mod_clks);
        WARN_DEBUG(mod->parent >= priv->num_core_clks + priv->num_mod_clks);
        WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT);

        if (!mod->name) {
                /* Skip NULLified clock */
                return;
        }

        parent = priv->clks[mod->parent];
        if (IS_ERR(parent)) {
                clk = parent;
                goto fail;
        }

        clock = kzalloc(sizeof(*clock), GFP_KERNEL);
        if (!clock) {
                clk = ERR_PTR(-ENOMEM);
                goto fail;
        }

        init.name = mod->name;
        init.ops = &cpg_mstp_clock_ops;
        init.flags = CLK_SET_RATE_PARENT;
        for (i = 0; i < info->num_crit_mod_clks; i++)
                if (id == info->crit_mod_clks[i]) {
                        dev_dbg(dev, "MSTP %s setting CLK_IS_CRITICAL\n",
                                mod->name);
                        init.flags |= CLK_IS_CRITICAL;
                        break;
                }

        parent_name = __clk_get_name(parent);
        init.parent_names = &parent_name;
        init.num_parents = 1;

        clock->index = id - priv->num_core_clks;
        clock->priv = priv;
        clock->hw.init = &init;

        clk = clk_register(NULL, &clock->hw);
        if (IS_ERR(clk))
                goto fail;

        dev_dbg(dev, "Module clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
        priv->clks[id] = clk;
        priv->smstpcr_saved[clock->index / 32].mask |= BIT(clock->index % 32);
        return;

fail:
        dev_err(dev, "Failed to register %s clock %s: %ld\n", "module",
                mod->name, PTR_ERR(clk));
        kfree(clock);
}

struct cpg_mssr_clk_domain {
        struct generic_pm_domain genpd;
        unsigned int num_core_pm_clks;
        unsigned int core_pm_clks[];
};

static struct cpg_mssr_clk_domain *cpg_mssr_clk_domain;

static bool cpg_mssr_is_pm_clk(const struct of_phandle_args *clkspec,
                               struct cpg_mssr_clk_domain *pd)
{
        unsigned int i;

        if (clkspec->np != pd->genpd.dev.of_node || clkspec->args_count != 2)
                return false;

        switch (clkspec->args[0]) {
        case CPG_CORE:
                for (i = 0; i < pd->num_core_pm_clks; i++)
                        if (clkspec->args[1] == pd->core_pm_clks[i])
                                return true;
                return false;

        case CPG_MOD:
                return true;

        default:
                return false;
        }
}

int cpg_mssr_attach_dev(struct generic_pm_domain *unused, struct device *dev)
{
        struct cpg_mssr_clk_domain *pd = cpg_mssr_clk_domain;
        struct device_node *np = dev->of_node;
        struct of_phandle_args clkspec;
        struct clk *clk;
        int i = 0;
        int error;

        if (!pd) {
                dev_dbg(dev, "CPG/MSSR clock domain not yet available\n");
                return -EPROBE_DEFER;
        }

        while (!of_parse_phandle_with_args(np, "clocks", "#clock-cells", i,
                                           &clkspec)) {
                if (cpg_mssr_is_pm_clk(&clkspec, pd))
                        goto found;

                of_node_put(clkspec.np);
                i++;
        }

        return 0;

found:
        clk = of_clk_get_from_provider(&clkspec);
        of_node_put(clkspec.np);

        if (IS_ERR(clk))
                return PTR_ERR(clk);

        error = pm_clk_create(dev);
        if (error)
                goto fail_put;

        error = pm_clk_add_clk(dev, clk);
        if (error)
                goto fail_destroy;

        return 0;

fail_destroy:
        pm_clk_destroy(dev);
fail_put:
        clk_put(clk);
        return error;
}

void cpg_mssr_detach_dev(struct generic_pm_domain *unused, struct device *dev)
{
        if (!pm_clk_no_clocks(dev))
                pm_clk_destroy(dev);
}

static int __init cpg_mssr_add_clk_domain(struct device *dev,
                                          const unsigned int *core_pm_clks,
                                          unsigned int num_core_pm_clks)
{
        struct device_node *np = dev->of_node;
        struct generic_pm_domain *genpd;
        struct cpg_mssr_clk_domain *pd;
        size_t pm_size = num_core_pm_clks * sizeof(core_pm_clks[0]);

        pd = devm_kzalloc(dev, sizeof(*pd) + pm_size, GFP_KERNEL);
        if (!pd)
                return -ENOMEM;

        pd->num_core_pm_clks = num_core_pm_clks;
        memcpy(pd->core_pm_clks, core_pm_clks, pm_size);

        genpd = &pd->genpd;
        genpd->name = np->name;
        genpd->flags = GENPD_FLAG_PM_CLK | GENPD_FLAG_ACTIVE_WAKEUP;
        genpd->attach_dev = cpg_mssr_attach_dev;
        genpd->detach_dev = cpg_mssr_detach_dev;
        pm_genpd_init(genpd, &pm_domain_always_on_gov, false);
        cpg_mssr_clk_domain = pd;

        of_genpd_add_provider_simple(np, genpd);
        return 0;
}

#ifdef CONFIG_RESET_CONTROLLER

#define rcdev_to_priv(x)        container_of(x, struct cpg_mssr_priv, rcdev)

static int cpg_mssr_reset(struct reset_controller_dev *rcdev,
                          unsigned long id)
{
        struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
        unsigned int reg = id / 32;
        unsigned int bit = id % 32;
        u32 bitmask = BIT(bit);

        dev_dbg(priv->dev, "reset %u%02u\n", reg, bit);

        /* Reset module */
        writel(bitmask, priv->base + SRCR(reg));

        /* Wait for at least one cycle of the RCLK clock (@ ca. 32 kHz) */
        udelay(35);

        /* Release module from reset state */
        writel(bitmask, priv->base + SRSTCLR(reg));

        return 0;
}

static int cpg_mssr_assert(struct reset_controller_dev *rcdev, unsigned long id)
{
        struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
        unsigned int reg = id / 32;
        unsigned int bit = id % 32;
        u32 bitmask = BIT(bit);

        dev_dbg(priv->dev, "assert %u%02u\n", reg, bit);

        writel(bitmask, priv->base + SRCR(reg));
        return 0;
}

static int cpg_mssr_deassert(struct reset_controller_dev *rcdev,
                             unsigned long id)
{
        struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
        unsigned int reg = id / 32;
        unsigned int bit = id % 32;
        u32 bitmask = BIT(bit);

        dev_dbg(priv->dev, "deassert %u%02u\n", reg, bit);

        writel(bitmask, priv->base + SRSTCLR(reg));
        return 0;
}

static int cpg_mssr_status(struct reset_controller_dev *rcdev,
                           unsigned long id)
{
        struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
        unsigned int reg = id / 32;
        unsigned int bit = id % 32;
        u32 bitmask = BIT(bit);

        return !!(readl(priv->base + SRCR(reg)) & bitmask);
}

static const struct reset_control_ops cpg_mssr_reset_ops = {
        .reset = cpg_mssr_reset,
        .assert = cpg_mssr_assert,
        .deassert = cpg_mssr_deassert,
        .status = cpg_mssr_status,
};

static int cpg_mssr_reset_xlate(struct reset_controller_dev *rcdev,
                                const struct of_phandle_args *reset_spec)
{
        struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
        unsigned int unpacked = reset_spec->args[0];
        unsigned int idx = MOD_CLK_PACK(unpacked);

        if (unpacked % 100 > 31 || idx >= rcdev->nr_resets) {
                dev_err(priv->dev, "Invalid reset index %u\n", unpacked);
                return -EINVAL;
        }

        return idx;
}

static int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
{
        priv->rcdev.ops = &cpg_mssr_reset_ops;
        priv->rcdev.of_node = priv->dev->of_node;
        priv->rcdev.of_reset_n_cells = 1;
        priv->rcdev.of_xlate = cpg_mssr_reset_xlate;
        priv->rcdev.nr_resets = priv->num_mod_clks;
        return devm_reset_controller_register(priv->dev, &priv->rcdev);
}

#else /* !CONFIG_RESET_CONTROLLER */
static inline int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
{
        return 0;
}
#endif /* !CONFIG_RESET_CONTROLLER */


static const struct of_device_id cpg_mssr_match[] = {
#ifdef CONFIG_CLK_R7S9210
        {
                .compatible = "renesas,r7s9210-cpg-mssr",
                .data = &r7s9210_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7743
        {
                .compatible = "renesas,r8a7743-cpg-mssr",
                .data = &r8a7743_cpg_mssr_info,
        },
        /* RZ/G1N is (almost) identical to RZ/G1M w.r.t. clocks. */
        {
                .compatible = "renesas,r8a7744-cpg-mssr",
                .data = &r8a7743_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7745
        {
                .compatible = "renesas,r8a7745-cpg-mssr",
                .data = &r8a7745_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A77470
        {
                .compatible = "renesas,r8a77470-cpg-mssr",
                .data = &r8a77470_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A774A1
        {
                .compatible = "renesas,r8a774a1-cpg-mssr",
                .data = &r8a774a1_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A774C0
        {
                .compatible = "renesas,r8a774c0-cpg-mssr",
                .data = &r8a774c0_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7790
        {
                .compatible = "renesas,r8a7790-cpg-mssr",
                .data = &r8a7790_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7791
        {
                .compatible = "renesas,r8a7791-cpg-mssr",
                .data = &r8a7791_cpg_mssr_info,
        },
        /* R-Car M2-N is (almost) identical to R-Car M2-W w.r.t. clocks. */
        {
                .compatible = "renesas,r8a7793-cpg-mssr",
                .data = &r8a7791_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7792
        {
                .compatible = "renesas,r8a7792-cpg-mssr",
                .data = &r8a7792_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7794
        {
                .compatible = "renesas,r8a7794-cpg-mssr",
                .data = &r8a7794_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7795
        {
                .compatible = "renesas,r8a7795-cpg-mssr",
                .data = &r8a7795_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A7796
        {
                .compatible = "renesas,r8a7796-cpg-mssr",
                .data = &r8a7796_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A77965
        {
                .compatible = "renesas,r8a77965-cpg-mssr",
                .data = &r8a77965_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A77970
        {
                .compatible = "renesas,r8a77970-cpg-mssr",
                .data = &r8a77970_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A77980
        {
                .compatible = "renesas,r8a77980-cpg-mssr",
                .data = &r8a77980_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A77990
        {
                .compatible = "renesas,r8a77990-cpg-mssr",
                .data = &r8a77990_cpg_mssr_info,
        },
#endif
#ifdef CONFIG_CLK_R8A77995
        {
                .compatible = "renesas,r8a77995-cpg-mssr",
                .data = &r8a77995_cpg_mssr_info,
        },
#endif
        { /* sentinel */ }
};

static void cpg_mssr_del_clk_provider(void *data)
{
        of_clk_del_provider(data);
}

#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_ARM_PSCI_FW)
static int cpg_mssr_suspend_noirq(struct device *dev)
{
        struct cpg_mssr_priv *priv = dev_get_drvdata(dev);
        unsigned int reg;

        /* This is the best we can do to check for the presence of PSCI */
        if (!psci_ops.cpu_suspend)
                return 0;

        /* Save module registers with bits under our control */
        for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
                if (priv->smstpcr_saved[reg].mask)
                        priv->smstpcr_saved[reg].val =
                                readl(priv->base + SMSTPCR(reg));
        }

        /* Save core clocks */
        raw_notifier_call_chain(&priv->notifiers, PM_EVENT_SUSPEND, NULL);

        return 0;
}

static int cpg_mssr_resume_noirq(struct device *dev)
{
        struct cpg_mssr_priv *priv = dev_get_drvdata(dev);
        unsigned int reg, i;
        u32 mask, oldval, newval;

        /* This is the best we can do to check for the presence of PSCI */
        if (!psci_ops.cpu_suspend)
                return 0;

        /* Restore core clocks */
        raw_notifier_call_chain(&priv->notifiers, PM_EVENT_RESUME, NULL);

        /* Restore module clocks */
        for (reg = 0; reg < ARRAY_SIZE(priv->smstpcr_saved); reg++) {
                mask = priv->smstpcr_saved[reg].mask;
                if (!mask)
                        continue;

                if (priv->stbyctrl)
                        oldval = readb(priv->base + STBCR(reg));
                else
                        oldval = readl(priv->base + SMSTPCR(reg));
                newval = oldval & ~mask;
                newval |= priv->smstpcr_saved[reg].val & mask;
                if (newval == oldval)
                        continue;

                if (priv->stbyctrl) {
                        writeb(newval, priv->base + STBCR(reg));
                        /* dummy read to ensure write has completed */
                        readb(priv->base + STBCR(reg));
                        barrier_data(priv->base + STBCR(reg));
                        continue;
                } else
                        writel(newval, priv->base + SMSTPCR(reg));

                /* Wait until enabled clocks are really enabled */
                mask &= ~priv->smstpcr_saved[reg].val;
                if (!mask)
                        continue;

                for (i = 1000; i > 0; --i) {
                        oldval = readl(priv->base + MSTPSR(reg));
                        if (!(oldval & mask))
                                break;
                        cpu_relax();
                }

                if (!i)
                        dev_warn(dev, "Failed to enable SMSTP %p[0x%x]\n",
                                 priv->base + SMSTPCR(reg), oldval & mask);
        }

        return 0;
}

static const struct dev_pm_ops cpg_mssr_pm = {
        SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(cpg_mssr_suspend_noirq,
                                      cpg_mssr_resume_noirq)
};
#define DEV_PM_OPS      &cpg_mssr_pm
#else
#define DEV_PM_OPS      NULL
#endif /* CONFIG_PM_SLEEP && CONFIG_ARM_PSCI_FW */

static int __init cpg_mssr_common_init(struct device *dev,
                                       struct device_node *np,
                                       const struct cpg_mssr_info *info)
{
        struct cpg_mssr_priv *priv;
        unsigned int nclks, i;
        int error;

        if (info->init) {
                error = info->init(dev);
                if (error)
                        return error;
        }

        nclks = info->num_total_core_clks + info->num_hw_mod_clks;
        priv = kzalloc(struct_size(priv, clks, nclks), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        priv->np = np;
        priv->dev = dev;
        spin_lock_init(&priv->rmw_lock);

        priv->base = of_iomap(np, 0);
        if (!priv->base) {
                error = -ENOMEM;
                goto out_err;
        }

        cpg_mssr_priv = priv;
        priv->num_core_clks = info->num_total_core_clks;
        priv->num_mod_clks = info->num_hw_mod_clks;
        priv->last_dt_core_clk = info->last_dt_core_clk;
        RAW_INIT_NOTIFIER_HEAD(&priv->notifiers);
        priv->stbyctrl = info->stbyctrl;

        for (i = 0; i < nclks; i++)
                priv->clks[i] = ERR_PTR(-ENOENT);

        error = of_clk_add_provider(np, cpg_mssr_clk_src_twocell_get, priv);
        if (error)
                goto out_err;

        return 0;

out_err:
        if (priv->base)
                iounmap(priv->base);
        kfree(priv);

        return error;
}

void __init cpg_mssr_early_init(struct device_node *np,
                                const struct cpg_mssr_info *info)
{
        int error;
        int i;

        error = cpg_mssr_common_init(NULL, np, info);
        if (error)
                return;

        for (i = 0; i < info->num_early_core_clks; i++)
                cpg_mssr_register_core_clk(&info->early_core_clks[i], info,
                                           cpg_mssr_priv);

        for (i = 0; i < info->num_early_mod_clks; i++)
                cpg_mssr_register_mod_clk(&info->early_mod_clks[i], info,
                                          cpg_mssr_priv);

}

static int __init cpg_mssr_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct device_node *np = dev->of_node;
        const struct cpg_mssr_info *info;
        struct cpg_mssr_priv *priv;
        unsigned int i;
        int error;

        info = of_device_get_match_data(dev);

        if (!cpg_mssr_priv) {
                error = cpg_mssr_common_init(dev, dev->of_node, info);
                if (error)
                        return error;
        }

        priv = cpg_mssr_priv;
        priv->dev = dev;
        dev_set_drvdata(dev, priv);

        for (i = 0; i < info->num_core_clks; i++)
                cpg_mssr_register_core_clk(&info->core_clks[i], info, priv);

        for (i = 0; i < info->num_mod_clks; i++)
                cpg_mssr_register_mod_clk(&info->mod_clks[i], info, priv);

        error = devm_add_action_or_reset(dev,
                                         cpg_mssr_del_clk_provider,
                                         np);
        if (error)
                return error;

        error = cpg_mssr_add_clk_domain(dev, info->core_pm_clks,
                                        info->num_core_pm_clks);
        if (error)
                return error;

        /* Reset Controller not supported for Standby Control SoCs */
        if (info->stbyctrl)
                return 0;

        error = cpg_mssr_reset_controller_register(priv);
        if (error)
                return error;

        return 0;
}

static struct platform_driver cpg_mssr_driver = {

        .driver         = {
                .name   = "renesas-cpg-mssr",
                .of_match_table = cpg_mssr_match,
                .pm = DEV_PM_OPS,
        },
};

static int __init cpg_mssr_init(void)
{
        return platform_driver_probe(&cpg_mssr_driver, cpg_mssr_probe);
}

subsys_initcall(cpg_mssr_init);

void __init cpg_core_nullify_range(struct cpg_core_clk *core_clks,
                                   unsigned int num_core_clks,
                                   unsigned int first_clk,
                                   unsigned int last_clk)
{
        unsigned int i;

        for (i = 0; i < num_core_clks; i++)
                if (core_clks[i].id >= first_clk &&
                    core_clks[i].id <= last_clk)
                        core_clks[i].name = NULL;
}

void __init mssr_mod_nullify(struct mssr_mod_clk *mod_clks,
                             unsigned int num_mod_clks,
                             const unsigned int *clks, unsigned int n)
{
        unsigned int i, j;

        for (i = 0, j = 0; i < num_mod_clks && j < n; i++)
                if (mod_clks[i].id == clks[j]) {
                        mod_clks[i].name = NULL;
                        j++;
                }
}

void __init mssr_mod_reparent(struct mssr_mod_clk *mod_clks,
                              unsigned int num_mod_clks,
                              const struct mssr_mod_reparent *clks,
                              unsigned int n)
{
        unsigned int i, j;

        for (i = 0, j = 0; i < num_mod_clks && j < n; i++)
                if (mod_clks[i].id == clks[j].clk) {
                        mod_clks[i].parent = clks[j].parent;
                        j++;
                }
}

MODULE_DESCRIPTION("Renesas CPG/MSSR Driver");
MODULE_LICENSE("GPL v2");