root/drivers/clk/ralink/clk-mtmips.c
// SPDX-License-Identifier: GPL-2.0
/*
 * MTMIPS SoCs Clock Driver
 * Author: Sergio Paracuellos <sergio.paracuellos@gmail.com>
 */

#include <linux/bitops.h>
#include <linux/clk-provider.h>
#include <linux/mfd/syscon.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset-controller.h>
#include <linux/slab.h>

/* Configuration registers */
#define SYSC_REG_SYSTEM_CONFIG          0x10
#define SYSC_REG_CLKCFG0                0x2c
#define SYSC_REG_RESET_CTRL             0x34
#define SYSC_REG_CPU_SYS_CLKCFG         0x3c
#define SYSC_REG_CPLL_CONFIG0           0x54
#define SYSC_REG_CPLL_CONFIG1           0x58

/* RT2880 SoC */
#define RT2880_CONFIG_CPUCLK_SHIFT      20
#define RT2880_CONFIG_CPUCLK_MASK       0x3
#define RT2880_CONFIG_CPUCLK_250        0x0
#define RT2880_CONFIG_CPUCLK_266        0x1
#define RT2880_CONFIG_CPUCLK_280        0x2
#define RT2880_CONFIG_CPUCLK_300        0x3

/* RT305X SoC */
#define RT305X_SYSCFG_CPUCLK_SHIFT      18
#define RT305X_SYSCFG_CPUCLK_MASK       0x1
#define RT305X_SYSCFG_CPUCLK_LOW        0x0
#define RT305X_SYSCFG_CPUCLK_HIGH       0x1

/* RT3352 SoC */
#define RT3352_SYSCFG0_CPUCLK_SHIFT     8
#define RT3352_SYSCFG0_CPUCLK_MASK      0x1
#define RT3352_SYSCFG0_CPUCLK_LOW       0x0
#define RT3352_SYSCFG0_CPUCLK_HIGH      0x1

/* RT3383 SoC */
#define RT3883_SYSCFG0_DRAM_TYPE_DDR2   BIT(17)
#define RT3883_SYSCFG0_CPUCLK_SHIFT     8
#define RT3883_SYSCFG0_CPUCLK_MASK      0x3
#define RT3883_SYSCFG0_CPUCLK_250       0x0
#define RT3883_SYSCFG0_CPUCLK_384       0x1
#define RT3883_SYSCFG0_CPUCLK_480       0x2
#define RT3883_SYSCFG0_CPUCLK_500       0x3

/* RT5350 SoC */
#define RT5350_CLKCFG0_XTAL_SEL         BIT(20)
#define RT5350_SYSCFG0_CPUCLK_SHIFT     8
#define RT5350_SYSCFG0_CPUCLK_MASK      0x3
#define RT5350_SYSCFG0_CPUCLK_360       0x0
#define RT5350_SYSCFG0_CPUCLK_320       0x2
#define RT5350_SYSCFG0_CPUCLK_300       0x3

/* MT7620 and MT76x8 SoCs */
#define MT7620_XTAL_FREQ_SEL            BIT(6)
#define CPLL_CFG0_SW_CFG                BIT(31)
#define CPLL_CFG0_PLL_MULT_RATIO_SHIFT  16
#define CPLL_CFG0_PLL_MULT_RATIO_MASK   0x7
#define CPLL_CFG0_LC_CURFCK             BIT(15)
#define CPLL_CFG0_BYPASS_REF_CLK        BIT(14)
#define CPLL_CFG0_PLL_DIV_RATIO_SHIFT   10
#define CPLL_CFG0_PLL_DIV_RATIO_MASK    0x3
#define CPLL_CFG1_CPU_AUX1              BIT(25)
#define CPLL_CFG1_CPU_AUX0              BIT(24)
#define CLKCFG0_PERI_CLK_SEL            BIT(4)
#define CPU_SYS_CLKCFG_OCP_RATIO_SHIFT  16
#define CPU_SYS_CLKCFG_OCP_RATIO_MASK   0xf
#define CPU_SYS_CLKCFG_OCP_RATIO_1      0       /* 1:1   (Reserved) */
#define CPU_SYS_CLKCFG_OCP_RATIO_1_5    1       /* 1:1.5 (Reserved) */
#define CPU_SYS_CLKCFG_OCP_RATIO_2      2       /* 1:2   */
#define CPU_SYS_CLKCFG_OCP_RATIO_2_5    3       /* 1:2.5 (Reserved) */
#define CPU_SYS_CLKCFG_OCP_RATIO_3      4       /* 1:3   */
#define CPU_SYS_CLKCFG_OCP_RATIO_3_5    5       /* 1:3.5 (Reserved) */
#define CPU_SYS_CLKCFG_OCP_RATIO_4      6       /* 1:4   */
#define CPU_SYS_CLKCFG_OCP_RATIO_5      7       /* 1:5   */
#define CPU_SYS_CLKCFG_OCP_RATIO_10     8       /* 1:10  */
#define CPU_SYS_CLKCFG_CPU_FDIV_SHIFT   8
#define CPU_SYS_CLKCFG_CPU_FDIV_MASK    0x1f
#define CPU_SYS_CLKCFG_CPU_FFRAC_SHIFT  0
#define CPU_SYS_CLKCFG_CPU_FFRAC_MASK   0x1f

/* clock scaling */
#define CLKCFG_FDIV_MASK                0x1f00
#define CLKCFG_FDIV_USB_VAL             0x0300
#define CLKCFG_FFRAC_MASK               0x001f
#define CLKCFG_FFRAC_USB_VAL            0x0003

struct mtmips_clk;
struct mtmips_clk_fixed;
struct mtmips_clk_factor;

struct mtmips_clk_data {
        struct mtmips_clk *clk_base;
        size_t num_clk_base;
        struct mtmips_clk_fixed *clk_fixed;
        size_t num_clk_fixed;
        struct mtmips_clk_factor *clk_factor;
        size_t num_clk_factor;
        struct mtmips_clk *clk_periph;
        size_t num_clk_periph;
};

struct mtmips_clk_priv {
        struct regmap *sysc;
        const struct mtmips_clk_data *data;
};

struct mtmips_clk {
        struct clk_hw hw;
        struct mtmips_clk_priv *priv;
};

struct mtmips_clk_fixed {
        const char *name;
        const char *parent;
        unsigned long rate;
        struct clk_hw *hw;
};

struct mtmips_clk_factor {
        const char *name;
        const char *parent;
        int mult;
        int div;
        unsigned long flags;
        struct clk_hw *hw;
};

static unsigned long mtmips_pherip_clk_rate(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        return parent_rate;
}

static const struct clk_ops mtmips_periph_clk_ops = {
        .recalc_rate = mtmips_pherip_clk_rate,
};

#define CLK_PERIPH(_name, _parent) {                            \
        .init = &(const struct clk_init_data) {                 \
                .name = _name,                                  \
                .ops = &mtmips_periph_clk_ops,                  \
                .parent_data = &(const struct clk_parent_data) {\
                        .name = _parent,                        \
                        .fw_name = _parent                      \
                },                                              \
                .num_parents = 1,                               \
                /*                                              \
                 * There are drivers for these SoCs that are    \
                 * older than clock driver and are not prepared \
                 * for the clock. We don't want the kernel to   \
                 * disable anything so we add CLK_IS_CRITICAL   \
                 * flag here.                                   \
                 */                                             \
                .flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL  \
        },                                                      \
}

static struct mtmips_clk rt2880_pherip_clks[] = {
        { CLK_PERIPH("300100.timer", "bus") },
        { CLK_PERIPH("300120.watchdog", "bus") },
        { CLK_PERIPH("300500.uart", "bus") },
        { CLK_PERIPH("300900.i2c", "bus") },
        { CLK_PERIPH("300c00.uartlite", "bus") },
        { CLK_PERIPH("400000.ethernet", "bus") },
        { CLK_PERIPH("480000.wmac", "xtal") }
};

static struct mtmips_clk rt305x_pherip_clks[] = {
        { CLK_PERIPH("10000100.timer", "bus") },
        { CLK_PERIPH("10000120.watchdog", "bus") },
        { CLK_PERIPH("10000500.uart", "bus") },
        { CLK_PERIPH("10000900.i2c", "bus") },
        { CLK_PERIPH("10000a00.i2s", "bus") },
        { CLK_PERIPH("10000b00.spi", "bus") },
        { CLK_PERIPH("10000b40.spi", "bus") },
        { CLK_PERIPH("10000c00.uartlite", "bus") },
        { CLK_PERIPH("10100000.ethernet", "bus") },
        { CLK_PERIPH("10180000.wmac", "xtal") }
};

static struct mtmips_clk rt5350_pherip_clks[] = {
        { CLK_PERIPH("10000100.timer", "bus") },
        { CLK_PERIPH("10000120.watchdog", "bus") },
        { CLK_PERIPH("10000500.uart", "periph") },
        { CLK_PERIPH("10000900.i2c", "periph") },
        { CLK_PERIPH("10000a00.i2s", "periph") },
        { CLK_PERIPH("10000b00.spi", "bus") },
        { CLK_PERIPH("10000b40.spi", "bus") },
        { CLK_PERIPH("10000c00.uartlite", "periph") },
        { CLK_PERIPH("10100000.ethernet", "bus") },
        { CLK_PERIPH("10180000.wmac", "xtal") }
};

static struct mtmips_clk mt7620_pherip_clks[] = {
        { CLK_PERIPH("10000100.timer", "periph") },
        { CLK_PERIPH("10000120.watchdog", "periph") },
        { CLK_PERIPH("10000500.uart", "periph") },
        { CLK_PERIPH("10000900.i2c", "periph") },
        { CLK_PERIPH("10000a00.i2s", "periph") },
        { CLK_PERIPH("10000b00.spi", "bus") },
        { CLK_PERIPH("10000b40.spi", "bus") },
        { CLK_PERIPH("10000c00.uartlite", "periph") },
        { CLK_PERIPH("10130000.mmc", "sdhc") },
        { CLK_PERIPH("10180000.wmac", "xtal") }
};

static struct mtmips_clk mt76x8_pherip_clks[] = {
        { CLK_PERIPH("10000100.timer", "periph") },
        { CLK_PERIPH("10000120.watchdog", "periph") },
        { CLK_PERIPH("10000900.i2c", "periph") },
        { CLK_PERIPH("10000a00.i2s", "pcmi2s") },
        { CLK_PERIPH("10000b00.spi", "bus") },
        { CLK_PERIPH("10000b40.spi", "bus") },
        { CLK_PERIPH("10000c00.uart0", "periph") },
        { CLK_PERIPH("10000d00.uart1", "periph") },
        { CLK_PERIPH("10000e00.uart2", "periph") },
        { CLK_PERIPH("10130000.mmc", "sdhc") },
        { CLK_PERIPH("10300000.wmac", "xtal") }
};

static int mtmips_register_pherip_clocks(struct device_node *np,
                                         struct clk_hw_onecell_data *clk_data,
                                         struct mtmips_clk_priv *priv)
{
        struct clk_hw **hws = clk_data->hws;
        struct mtmips_clk *sclk;
        size_t idx_start = priv->data->num_clk_base + priv->data->num_clk_fixed +
                           priv->data->num_clk_factor;
        int ret, i;

        for (i = 0; i < priv->data->num_clk_periph; i++) {
                int idx = idx_start + i;

                sclk = &priv->data->clk_periph[i];
                ret = of_clk_hw_register(np, &sclk->hw);
                if (ret) {
                        pr_err("Couldn't register peripheral clock %d\n", idx);
                        goto err_clk_unreg;
                }

                hws[idx] = &sclk->hw;
        }

        return 0;

err_clk_unreg:
        while (--i >= 0) {
                sclk = &priv->data->clk_periph[i];
                clk_hw_unregister(&sclk->hw);
        }
        return ret;
}

#define CLK_FIXED(_name, _parent, _rate) \
        {                                \
                .name = _name,           \
                .parent = _parent,       \
                .rate = _rate            \
        }

static struct mtmips_clk_fixed rt3883_fixed_clocks[] = {
        CLK_FIXED("periph", "xtal", 40000000)
};

static struct mtmips_clk_fixed rt3352_fixed_clocks[] = {
        CLK_FIXED("periph", "xtal", 40000000)
};

static struct mtmips_clk_fixed mt7620_fixed_clocks[] = {
        CLK_FIXED("bbppll", "xtal", 480000000)
};

static struct mtmips_clk_fixed mt76x8_fixed_clocks[] = {
        CLK_FIXED("bbppll", "xtal", 480000000),
        CLK_FIXED("pcmi2s", "bbppll", 480000000),
        CLK_FIXED("periph", "xtal", 40000000)
};

static int mtmips_register_fixed_clocks(struct clk_hw_onecell_data *clk_data,
                                        struct mtmips_clk_priv *priv)
{
        struct clk_hw **hws = clk_data->hws;
        struct mtmips_clk_fixed *sclk;
        size_t idx_start = priv->data->num_clk_base;
        int ret, i;

        for (i = 0; i < priv->data->num_clk_fixed; i++) {
                int idx = idx_start + i;

                sclk = &priv->data->clk_fixed[i];
                sclk->hw = clk_hw_register_fixed_rate(NULL, sclk->name,
                                                      sclk->parent, 0,
                                                      sclk->rate);
                if (IS_ERR(sclk->hw)) {
                        ret = PTR_ERR(sclk->hw);
                        pr_err("Couldn't register fixed clock %d\n", idx);
                        goto err_clk_unreg;
                }

                hws[idx] = sclk->hw;
        }

        return 0;

err_clk_unreg:
        while (--i >= 0) {
                sclk = &priv->data->clk_fixed[i];
                clk_hw_unregister_fixed_rate(sclk->hw);
        }
        return ret;
}

#define CLK_FACTOR(_name, _parent, _mult, _div)         \
        {                                               \
                .name = _name,                          \
                .parent = _parent,                      \
                .mult = _mult,                          \
                .div = _div,                            \
                .flags = CLK_SET_RATE_PARENT            \
        }

static struct mtmips_clk_factor rt2880_factor_clocks[] = {
        CLK_FACTOR("bus", "cpu", 1, 2)
};

static struct mtmips_clk_factor rt305x_factor_clocks[] = {
        CLK_FACTOR("bus", "cpu", 1, 3)
};

static struct mtmips_clk_factor mt7620_factor_clocks[] = {
        CLK_FACTOR("sdhc", "bbppll", 1, 10)
};

static struct mtmips_clk_factor mt76x8_factor_clocks[] = {
        CLK_FACTOR("bus", "cpu", 1, 3),
        CLK_FACTOR("sdhc", "bbppll", 1, 10)
};

static int mtmips_register_factor_clocks(struct clk_hw_onecell_data *clk_data,
                                         struct mtmips_clk_priv *priv)
{
        struct clk_hw **hws = clk_data->hws;
        struct mtmips_clk_factor *sclk;
        size_t idx_start = priv->data->num_clk_base + priv->data->num_clk_fixed;
        int ret, i;

        for (i = 0; i < priv->data->num_clk_factor; i++) {
                int idx = idx_start + i;

                sclk = &priv->data->clk_factor[i];
                sclk->hw = clk_hw_register_fixed_factor(NULL, sclk->name,
                                                  sclk->parent, sclk->flags,
                                                  sclk->mult, sclk->div);
                if (IS_ERR(sclk->hw)) {
                        ret = PTR_ERR(sclk->hw);
                        pr_err("Couldn't register factor clock %d\n", idx);
                        goto err_clk_unreg;
                }

                hws[idx] = sclk->hw;
        }

        return 0;

err_clk_unreg:
        while (--i >= 0) {
                sclk = &priv->data->clk_factor[i];
                clk_hw_unregister_fixed_factor(sclk->hw);
        }
        return ret;
}

static inline struct mtmips_clk *to_mtmips_clk(struct clk_hw *hw)
{
        return container_of(hw, struct mtmips_clk, hw);
}

static unsigned long rt2880_xtal_recalc_rate(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        return 40000000;
}

static unsigned long rt5350_xtal_recalc_rate(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 val;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &val);
        if (!(val & RT5350_CLKCFG0_XTAL_SEL))
                return 20000000;

        return 40000000;
}

static unsigned long rt5350_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long xtal_clk)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        t = (t >> RT5350_SYSCFG0_CPUCLK_SHIFT) & RT5350_SYSCFG0_CPUCLK_MASK;

        switch (t) {
        case RT5350_SYSCFG0_CPUCLK_360:
                return 360000000;
        case RT5350_SYSCFG0_CPUCLK_320:
                return 320000000;
        case RT5350_SYSCFG0_CPUCLK_300:
                return 300000000;
        default:
                BUG();
        }
}

static unsigned long rt5350_bus_recalc_rate(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        if (parent_rate == 320000000)
                return parent_rate / 4;

        return parent_rate / 3;
}

static unsigned long rt3352_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long xtal_clk)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        t = (t >> RT3352_SYSCFG0_CPUCLK_SHIFT) & RT3352_SYSCFG0_CPUCLK_MASK;

        switch (t) {
        case RT3352_SYSCFG0_CPUCLK_LOW:
                return 384000000;
        case RT3352_SYSCFG0_CPUCLK_HIGH:
                return 400000000;
        default:
                BUG();
        }
}

static unsigned long rt305x_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long xtal_clk)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        t = (t >> RT305X_SYSCFG_CPUCLK_SHIFT) & RT305X_SYSCFG_CPUCLK_MASK;

        switch (t) {
        case RT305X_SYSCFG_CPUCLK_LOW:
                return 320000000;
        case RT305X_SYSCFG_CPUCLK_HIGH:
                return 384000000;
        default:
                BUG();
        }
}

static unsigned long rt3883_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long xtal_clk)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        t = (t >> RT3883_SYSCFG0_CPUCLK_SHIFT) & RT3883_SYSCFG0_CPUCLK_MASK;

        switch (t) {
        case RT3883_SYSCFG0_CPUCLK_250:
                return 250000000;
        case RT3883_SYSCFG0_CPUCLK_384:
                return 384000000;
        case RT3883_SYSCFG0_CPUCLK_480:
                return 480000000;
        case RT3883_SYSCFG0_CPUCLK_500:
                return 500000000;
        default:
                BUG();
        }
}

static unsigned long rt3883_bus_recalc_rate(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 ddr2;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        ddr2 = t & RT3883_SYSCFG0_DRAM_TYPE_DDR2;

        switch (parent_rate) {
        case 250000000:
                return (ddr2) ? 125000000 : 83000000;
        case 384000000:
                return (ddr2) ? 128000000 : 96000000;
        case 480000000:
                return (ddr2) ? 160000000 : 120000000;
        case 500000000:
                return (ddr2) ? 166000000 : 125000000;
        default:
                WARN_ON_ONCE(parent_rate == 0);
                return parent_rate / 4;
        }
}

static unsigned long rt2880_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long xtal_clk)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        t = (t >> RT2880_CONFIG_CPUCLK_SHIFT) & RT2880_CONFIG_CPUCLK_MASK;

        switch (t) {
        case RT2880_CONFIG_CPUCLK_250:
                return 250000000;
        case RT2880_CONFIG_CPUCLK_266:
                return 266000000;
        case RT2880_CONFIG_CPUCLK_280:
                return 280000000;
        case RT2880_CONFIG_CPUCLK_300:
                return 300000000;
        default:
                BUG();
        }
}

static u32 mt7620_calc_rate(u32 ref_rate, u32 mul, u32 div)
{
        u64 t;

        t = ref_rate;
        t *= mul;
        t = div_u64(t, div);

        return t;
}

static unsigned long mt7620_pll_recalc_rate(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        static const u32 clk_divider[] = { 2, 3, 4, 8 };
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        unsigned long cpu_pll;
        u32 t;
        u32 mul;
        u32 div;

        regmap_read(sysc, SYSC_REG_CPLL_CONFIG0, &t);
        if (t & CPLL_CFG0_BYPASS_REF_CLK) {
                cpu_pll = parent_rate;
        } else if ((t & CPLL_CFG0_SW_CFG) == 0) {
                cpu_pll = 600000000;
        } else {
                mul = (t >> CPLL_CFG0_PLL_MULT_RATIO_SHIFT) &
                        CPLL_CFG0_PLL_MULT_RATIO_MASK;
                mul += 24;
                if (t & CPLL_CFG0_LC_CURFCK)
                        mul *= 2;

                div = (t >> CPLL_CFG0_PLL_DIV_RATIO_SHIFT) &
                        CPLL_CFG0_PLL_DIV_RATIO_MASK;

                WARN_ON_ONCE(div >= ARRAY_SIZE(clk_divider));

                cpu_pll = mt7620_calc_rate(parent_rate, mul, clk_divider[div]);
        }

        regmap_read(sysc, SYSC_REG_CPLL_CONFIG1, &t);
        if (t & CPLL_CFG1_CPU_AUX1)
                return parent_rate;

        if (t & CPLL_CFG1_CPU_AUX0)
                return 480000000;

        return cpu_pll;
}

static unsigned long mt7620_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;
        u32 mul;
        u32 div;

        regmap_read(sysc, SYSC_REG_CPU_SYS_CLKCFG, &t);
        mul = t & CPU_SYS_CLKCFG_CPU_FFRAC_MASK;
        div = (t >> CPU_SYS_CLKCFG_CPU_FDIV_SHIFT) &
                CPU_SYS_CLKCFG_CPU_FDIV_MASK;

        return mt7620_calc_rate(parent_rate, mul, div);
}

static unsigned long mt7620_bus_recalc_rate(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        static const u32 ocp_dividers[16] = {
                [CPU_SYS_CLKCFG_OCP_RATIO_2] = 2,
                [CPU_SYS_CLKCFG_OCP_RATIO_3] = 3,
                [CPU_SYS_CLKCFG_OCP_RATIO_4] = 4,
                [CPU_SYS_CLKCFG_OCP_RATIO_5] = 5,
                [CPU_SYS_CLKCFG_OCP_RATIO_10] = 10,
        };
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;
        u32 ocp_ratio;
        u32 div;

        regmap_read(sysc, SYSC_REG_CPU_SYS_CLKCFG, &t);
        ocp_ratio = (t >> CPU_SYS_CLKCFG_OCP_RATIO_SHIFT) &
                CPU_SYS_CLKCFG_OCP_RATIO_MASK;

        if (WARN_ON_ONCE(ocp_ratio >= ARRAY_SIZE(ocp_dividers)))
                return parent_rate;

        div = ocp_dividers[ocp_ratio];

        if (WARN(!div, "invalid divider for OCP ratio %u", ocp_ratio))
                return parent_rate;

        return parent_rate / div;
}

static unsigned long mt7620_periph_recalc_rate(struct clk_hw *hw,
                                               unsigned long parent_rate)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_CLKCFG0, &t);
        if (t & CLKCFG0_PERI_CLK_SEL)
                return parent_rate;

        return 40000000;
}

static unsigned long mt76x8_xtal_recalc_rate(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        struct mtmips_clk *clk = to_mtmips_clk(hw);
        struct regmap *sysc = clk->priv->sysc;
        u32 t;

        regmap_read(sysc, SYSC_REG_SYSTEM_CONFIG, &t);
        if (t & MT7620_XTAL_FREQ_SEL)
                return 40000000;

        return 20000000;
}

static unsigned long mt76x8_cpu_recalc_rate(struct clk_hw *hw,
                                            unsigned long xtal_clk)
{
        if (xtal_clk == 40000000)
                return 580000000;

        return 575000000;
}

#define CLK_BASE(_name, _parent, _recalc) {                             \
        .init = &(const struct clk_init_data) {                         \
                .name = _name,                                          \
                .ops = &(const struct clk_ops) {                        \
                        .recalc_rate = _recalc,                         \
                },                                                      \
                .parent_data = &(const struct clk_parent_data) {        \
                        .name = _parent,                                \
                        .fw_name = _parent                              \
                },                                                      \
                .num_parents = _parent ? 1 : 0                          \
        },                                                              \
}

static struct mtmips_clk rt2880_clks_base[] = {
        { CLK_BASE("xtal", NULL, rt2880_xtal_recalc_rate) },
        { CLK_BASE("cpu", "xtal", rt2880_cpu_recalc_rate) }
};

static struct mtmips_clk rt305x_clks_base[] = {
        { CLK_BASE("xtal", NULL, rt2880_xtal_recalc_rate) },
        { CLK_BASE("cpu", "xtal", rt305x_cpu_recalc_rate) }
};

static struct mtmips_clk rt3352_clks_base[] = {
        { CLK_BASE("xtal", NULL, rt5350_xtal_recalc_rate) },
        { CLK_BASE("cpu", "xtal", rt3352_cpu_recalc_rate) }
};

static struct mtmips_clk rt3883_clks_base[] = {
        { CLK_BASE("xtal", NULL, rt2880_xtal_recalc_rate) },
        { CLK_BASE("cpu", "xtal", rt3883_cpu_recalc_rate) },
        { CLK_BASE("bus", "cpu", rt3883_bus_recalc_rate) }
};

static struct mtmips_clk rt5350_clks_base[] = {
        { CLK_BASE("xtal", NULL, rt5350_xtal_recalc_rate) },
        { CLK_BASE("cpu", "xtal", rt5350_cpu_recalc_rate) },
        { CLK_BASE("bus", "cpu", rt5350_bus_recalc_rate) }
};

static struct mtmips_clk mt7620_clks_base[] = {
        { CLK_BASE("xtal", NULL, mt76x8_xtal_recalc_rate) },
        { CLK_BASE("pll", "xtal", mt7620_pll_recalc_rate) },
        { CLK_BASE("cpu", "pll", mt7620_cpu_recalc_rate) },
        { CLK_BASE("periph", "xtal", mt7620_periph_recalc_rate) },
        { CLK_BASE("bus", "cpu", mt7620_bus_recalc_rate) }
};

static struct mtmips_clk mt76x8_clks_base[] = {
        { CLK_BASE("xtal", NULL, mt76x8_xtal_recalc_rate) },
        { CLK_BASE("cpu", "xtal", mt76x8_cpu_recalc_rate) }
};

static int mtmips_register_clocks(struct device_node *np,
                                  struct clk_hw_onecell_data *clk_data,
                                  struct mtmips_clk_priv *priv)
{
        struct clk_hw **hws = clk_data->hws;
        struct mtmips_clk *sclk;
        int ret, i;

        for (i = 0; i < priv->data->num_clk_base; i++) {
                sclk = &priv->data->clk_base[i];
                sclk->priv = priv;
                ret = of_clk_hw_register(np, &sclk->hw);
                if (ret) {
                        pr_err("Couldn't register top clock %i\n", i);
                        goto err_clk_unreg;
                }

                hws[i] = &sclk->hw;
        }

        return 0;

err_clk_unreg:
        while (--i >= 0) {
                sclk = &priv->data->clk_base[i];
                clk_hw_unregister(&sclk->hw);
        }
        return ret;
}

static const struct mtmips_clk_data rt2880_clk_data = {
        .clk_base = rt2880_clks_base,
        .num_clk_base = ARRAY_SIZE(rt2880_clks_base),
        .clk_fixed = NULL,
        .num_clk_fixed = 0,
        .clk_factor = rt2880_factor_clocks,
        .num_clk_factor = ARRAY_SIZE(rt2880_factor_clocks),
        .clk_periph = rt2880_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(rt2880_pherip_clks),
};

static const struct mtmips_clk_data rt305x_clk_data = {
        .clk_base = rt305x_clks_base,
        .num_clk_base = ARRAY_SIZE(rt305x_clks_base),
        .clk_fixed = NULL,
        .num_clk_fixed = 0,
        .clk_factor = rt305x_factor_clocks,
        .num_clk_factor = ARRAY_SIZE(rt305x_factor_clocks),
        .clk_periph = rt305x_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(rt305x_pherip_clks),
};

static const struct mtmips_clk_data rt3352_clk_data = {
        .clk_base = rt3352_clks_base,
        .num_clk_base = ARRAY_SIZE(rt3352_clks_base),
        .clk_fixed = rt3352_fixed_clocks,
        .num_clk_fixed = ARRAY_SIZE(rt3352_fixed_clocks),
        .clk_factor = rt305x_factor_clocks,
        .num_clk_factor = ARRAY_SIZE(rt305x_factor_clocks),
        .clk_periph = rt5350_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(rt5350_pherip_clks),
};

static const struct mtmips_clk_data rt3883_clk_data = {
        .clk_base = rt3883_clks_base,
        .num_clk_base = ARRAY_SIZE(rt3883_clks_base),
        .clk_fixed = rt3883_fixed_clocks,
        .num_clk_fixed = ARRAY_SIZE(rt3883_fixed_clocks),
        .clk_factor = NULL,
        .num_clk_factor = 0,
        .clk_periph = rt5350_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(rt5350_pherip_clks),
};

static const struct mtmips_clk_data rt5350_clk_data = {
        .clk_base = rt5350_clks_base,
        .num_clk_base = ARRAY_SIZE(rt5350_clks_base),
        .clk_fixed = rt3352_fixed_clocks,
        .num_clk_fixed = ARRAY_SIZE(rt3352_fixed_clocks),
        .clk_factor = NULL,
        .num_clk_factor = 0,
        .clk_periph = rt5350_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(rt5350_pherip_clks),
};

static const struct mtmips_clk_data mt7620_clk_data = {
        .clk_base = mt7620_clks_base,
        .num_clk_base = ARRAY_SIZE(mt7620_clks_base),
        .clk_fixed = mt7620_fixed_clocks,
        .num_clk_fixed = ARRAY_SIZE(mt7620_fixed_clocks),
        .clk_factor = mt7620_factor_clocks,
        .num_clk_factor = ARRAY_SIZE(mt7620_factor_clocks),
        .clk_periph = mt7620_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(mt7620_pherip_clks),
};

static const struct mtmips_clk_data mt76x8_clk_data = {
        .clk_base = mt76x8_clks_base,
        .num_clk_base = ARRAY_SIZE(mt76x8_clks_base),
        .clk_fixed = mt76x8_fixed_clocks,
        .num_clk_fixed = ARRAY_SIZE(mt76x8_fixed_clocks),
        .clk_factor = mt76x8_factor_clocks,
        .num_clk_factor = ARRAY_SIZE(mt76x8_factor_clocks),
        .clk_periph = mt76x8_pherip_clks,
        .num_clk_periph = ARRAY_SIZE(mt76x8_pherip_clks),
};

static const struct of_device_id mtmips_of_match[] = {
        {
                .compatible = "ralink,rt2880-reset",
                .data = NULL,
        },
        {
                .compatible = "ralink,rt2880-sysc",
                .data = &rt2880_clk_data,
        },
        {
                .compatible = "ralink,rt3050-sysc",
                .data = &rt305x_clk_data,
        },
        {
                .compatible = "ralink,rt3052-sysc",
                .data = &rt305x_clk_data,
        },
        {
                .compatible = "ralink,rt3352-sysc",
                .data = &rt3352_clk_data,
        },
        {
                .compatible = "ralink,rt3883-sysc",
                .data = &rt3883_clk_data,
        },
        {
                .compatible = "ralink,rt5350-sysc",
                .data = &rt5350_clk_data,
        },
        {
                .compatible = "ralink,mt7620-sysc",
                .data = &mt7620_clk_data,
        },
        {
                .compatible = "ralink,mt7628-sysc",
                .data = &mt76x8_clk_data,
        },
        {
                .compatible = "ralink,mt7688-sysc",
                .data = &mt76x8_clk_data,
        },
        {}
};

static void __init mtmips_clk_regs_init(struct device_node *node,
                                        struct mtmips_clk_priv *priv)
{
        u32 t;

        if (!of_device_is_compatible(node, "ralink,mt7620-sysc"))
                return;

        /*
         * When the CPU goes into sleep mode, the BUS
         * clock will be too low for USB to function properly.
         * Adjust the busses fractional divider to fix this
         */
        regmap_read(priv->sysc, SYSC_REG_CPU_SYS_CLKCFG, &t);
        t &= ~(CLKCFG_FDIV_MASK | CLKCFG_FFRAC_MASK);
        t |= CLKCFG_FDIV_USB_VAL | CLKCFG_FFRAC_USB_VAL;
        regmap_write(priv->sysc, SYSC_REG_CPU_SYS_CLKCFG, t);
}

static void __init mtmips_clk_init(struct device_node *node)
{
        const struct of_device_id *match;
        const struct mtmips_clk_data *data;
        struct mtmips_clk_priv *priv;
        struct clk_hw_onecell_data *clk_data;
        int ret, i, count;

        priv = kzalloc_obj(*priv);
        if (!priv)
                return;

        priv->sysc = syscon_node_to_regmap(node);
        if (IS_ERR(priv->sysc)) {
                pr_err("Could not get sysc syscon regmap\n");
                goto free_clk_priv;
        }

        mtmips_clk_regs_init(node, priv);

        match = of_match_node(mtmips_of_match, node);
        if (WARN_ON(!match))
                return;

        data = match->data;
        priv->data = data;
        count = priv->data->num_clk_base + priv->data->num_clk_fixed +
                priv->data->num_clk_factor + priv->data->num_clk_periph;
        clk_data = kzalloc_flex(*clk_data, hws, count);
        if (!clk_data)
                goto free_clk_priv;

        ret = mtmips_register_clocks(node, clk_data, priv);
        if (ret) {
                pr_err("Couldn't register top clocks\n");
                goto free_clk_data;
        }

        ret = mtmips_register_fixed_clocks(clk_data, priv);
        if (ret) {
                pr_err("Couldn't register fixed clocks\n");
                goto unreg_clk_top;
        }

        ret = mtmips_register_factor_clocks(clk_data, priv);
        if (ret) {
                pr_err("Couldn't register factor clocks\n");
                goto unreg_clk_fixed;
        }

        ret = mtmips_register_pherip_clocks(node, clk_data, priv);
        if (ret) {
                pr_err("Couldn't register peripheral clocks\n");
                goto unreg_clk_factor;
        }

        clk_data->num = count;

        ret = of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data);
        if (ret) {
                pr_err("Couldn't add clk hw provider\n");
                goto unreg_clk_periph;
        }

        return;

unreg_clk_periph:
        for (i = 0; i < priv->data->num_clk_periph; i++) {
                struct mtmips_clk *sclk = &priv->data->clk_periph[i];

                clk_hw_unregister(&sclk->hw);
        }

unreg_clk_factor:
        for (i = 0; i < priv->data->num_clk_factor; i++) {
                struct mtmips_clk_factor *sclk = &priv->data->clk_factor[i];

                clk_hw_unregister_fixed_factor(sclk->hw);
        }

unreg_clk_fixed:
        for (i = 0; i < priv->data->num_clk_fixed; i++) {
                struct mtmips_clk_fixed *sclk = &priv->data->clk_fixed[i];

                clk_hw_unregister_fixed_rate(sclk->hw);
        }

unreg_clk_top:
        for (i = 0; i < priv->data->num_clk_base; i++) {
                struct mtmips_clk *sclk = &priv->data->clk_base[i];

                clk_hw_unregister(&sclk->hw);
        }

free_clk_data:
        kfree(clk_data);

free_clk_priv:
        kfree(priv);
}
CLK_OF_DECLARE_DRIVER(rt2880_clk, "ralink,rt2880-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(rt3050_clk, "ralink,rt3050-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(rt3052_clk, "ralink,rt3052-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(rt3352_clk, "ralink,rt3352-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(rt3883_clk, "ralink,rt3883-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(rt5350_clk, "ralink,rt5350-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(mt7620_clk, "ralink,mt7620-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(mt7628_clk, "ralink,mt7628-sysc", mtmips_clk_init);
CLK_OF_DECLARE_DRIVER(mt7688_clk, "ralink,mt7688-sysc", mtmips_clk_init);

struct mtmips_rst {
        struct reset_controller_dev rcdev;
        struct regmap *sysc;
};

static struct mtmips_rst *to_mtmips_rst(struct reset_controller_dev *dev)
{
        return container_of(dev, struct mtmips_rst, rcdev);
}

static int mtmips_assert_device(struct reset_controller_dev *rcdev,
                                unsigned long id)
{
        struct mtmips_rst *data = to_mtmips_rst(rcdev);
        struct regmap *sysc = data->sysc;

        return regmap_update_bits(sysc, SYSC_REG_RESET_CTRL, BIT(id), BIT(id));
}

static int mtmips_deassert_device(struct reset_controller_dev *rcdev,
                                  unsigned long id)
{
        struct mtmips_rst *data = to_mtmips_rst(rcdev);
        struct regmap *sysc = data->sysc;

        return regmap_update_bits(sysc, SYSC_REG_RESET_CTRL, BIT(id), 0);
}

static int mtmips_reset_device(struct reset_controller_dev *rcdev,
                               unsigned long id)
{
        int ret;

        ret = mtmips_assert_device(rcdev, id);
        if (ret < 0)
                return ret;

        return mtmips_deassert_device(rcdev, id);
}

static int mtmips_rst_xlate(struct reset_controller_dev *rcdev,
                            const struct of_phandle_args *reset_spec)
{
        unsigned long id = reset_spec->args[0];

        if (id == 0 || id >= rcdev->nr_resets)
                return -EINVAL;

        return id;
}

static const struct reset_control_ops reset_ops = {
        .reset = mtmips_reset_device,
        .assert = mtmips_assert_device,
        .deassert = mtmips_deassert_device
};

static int mtmips_reset_init(struct device *dev, struct regmap *sysc)
{
        struct mtmips_rst *rst_data;

        rst_data = devm_kzalloc(dev, sizeof(*rst_data), GFP_KERNEL);
        if (!rst_data)
                return -ENOMEM;

        rst_data->sysc = sysc;
        rst_data->rcdev.ops = &reset_ops;
        rst_data->rcdev.owner = THIS_MODULE;
        rst_data->rcdev.nr_resets = 32;
        rst_data->rcdev.of_reset_n_cells = 1;
        rst_data->rcdev.of_xlate = mtmips_rst_xlate;
        rst_data->rcdev.of_node = dev_of_node(dev);

        return devm_reset_controller_register(dev, &rst_data->rcdev);
}

static int mtmips_clk_probe(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        struct device *dev = &pdev->dev;
        struct mtmips_clk_priv *priv;
        int ret;

        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        priv->sysc = syscon_node_to_regmap(np);
        if (IS_ERR(priv->sysc))
                return dev_err_probe(dev, PTR_ERR(priv->sysc),
                                     "Could not get sysc syscon regmap\n");

        ret = mtmips_reset_init(dev, priv->sysc);
        if (ret)
                return dev_err_probe(dev, ret, "Could not init reset controller\n");

        return 0;
}

static struct platform_driver mtmips_clk_driver = {
        .probe = mtmips_clk_probe,
        .driver = {
                .name = "mtmips-clk",
                .of_match_table = mtmips_of_match,
        },
};

static int __init mtmips_clk_reset_init(void)
{
        return platform_driver_register(&mtmips_clk_driver);
}
arch_initcall(mtmips_clk_reset_init);