module: Convert symbol namespace to string literal

[linux.git] / drivers / clk / microchip / clk-mpfs.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * PolarFire SoC MSS/core complex clock control
 *
 * Copyright (C) 2020-2022 Microchip Technology Inc. All rights reserved.
 */
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <dt-bindings/clock/microchip,mpfs-clock.h>
#include <soc/microchip/mpfs.h>

/* address offset of control registers */
#define REG_MSSPLL_REF_CR       0x08u
#define REG_MSSPLL_POSTDIV01_CR 0x10u
#define REG_MSSPLL_POSTDIV23_CR 0x14u
#define REG_MSSPLL_SSCG_2_CR    0x2Cu
#define REG_CLOCK_CONFIG_CR     0x08u
#define REG_RTC_CLOCK_CR        0x0Cu
#define REG_SUBBLK_CLOCK_CR     0x84u
#define REG_SUBBLK_RESET_CR     0x88u

#define MSSPLL_FBDIV_SHIFT      0x00u
#define MSSPLL_FBDIV_WIDTH      0x0Cu
#define MSSPLL_REFDIV_SHIFT     0x08u
#define MSSPLL_REFDIV_WIDTH     0x06u
#define MSSPLL_POSTDIV02_SHIFT  0x08u
#define MSSPLL_POSTDIV13_SHIFT  0x18u
#define MSSPLL_POSTDIV_WIDTH    0x07u
#define MSSPLL_FIXED_DIV        4u

/*
 * This clock ID is defined here, rather than the binding headers, as it is an
 * internal clock only, and therefore has no consumers in other peripheral
 * blocks.
 */
#define CLK_MSSPLL_INTERNAL     38u

struct mpfs_clock_data {
        struct device *dev;
        void __iomem *base;
        void __iomem *msspll_base;
        struct clk_hw_onecell_data hw_data;
};

struct mpfs_msspll_hw_clock {
        void __iomem *base;
        struct clk_hw hw;
        struct clk_init_data init;
        unsigned int id;
        u32 reg_offset;
        u32 shift;
        u32 width;
        u32 flags;
};

#define to_mpfs_msspll_clk(_hw) container_of(_hw, struct mpfs_msspll_hw_clock, hw)

struct mpfs_msspll_out_hw_clock {
        void __iomem *base;
        struct clk_divider output;
        struct clk_init_data init;
        unsigned int id;
        u32 reg_offset;
};

#define to_mpfs_msspll_out_clk(_hw) container_of(_hw, struct mpfs_msspll_out_hw_clock, hw)

struct mpfs_cfg_hw_clock {
        struct clk_divider cfg;
        struct clk_init_data init;
        unsigned int id;
        u32 reg_offset;
};

struct mpfs_periph_hw_clock {
        struct clk_gate periph;
        unsigned int id;
};

/*
 * mpfs_clk_lock prevents anything else from writing to the
 * mpfs clk block while a software locked register is being written.
 */
static DEFINE_SPINLOCK(mpfs_clk_lock);

static const struct clk_parent_data mpfs_ext_ref[] = {
        { .index = 0 },
};

static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
        { 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
        { 0, 0 }
};

static const struct clk_div_table mpfs_div_ahb_table[] = {
        { 1, 2 }, { 2, 4}, { 3, 8 },
        { 0, 0 }
};

/*
 * The only two supported reference clock frequencies for the PolarFire SoC are
 * 100 and 125 MHz, as the rtc reference is required to be 1 MHz.
 * It therefore only needs to have divider table entries corresponding to
 * divide by 100 and 125.
 */
static const struct clk_div_table mpfs_div_rtcref_table[] = {
        { 100, 100 }, { 125, 125 },
        { 0, 0 }
};

/*
 * MSS PLL internal clock
 */

static unsigned long mpfs_clk_msspll_recalc_rate(struct clk_hw *hw, unsigned long prate)
{
        struct mpfs_msspll_hw_clock *msspll_hw = to_mpfs_msspll_clk(hw);
        void __iomem *mult_addr = msspll_hw->base + msspll_hw->reg_offset;
        void __iomem *ref_div_addr = msspll_hw->base + REG_MSSPLL_REF_CR;
        u32 mult, ref_div;

        mult = readl_relaxed(mult_addr) >> MSSPLL_FBDIV_SHIFT;
        mult &= clk_div_mask(MSSPLL_FBDIV_WIDTH);
        ref_div = readl_relaxed(ref_div_addr) >> MSSPLL_REFDIV_SHIFT;
        ref_div &= clk_div_mask(MSSPLL_REFDIV_WIDTH);

        return prate * mult / (ref_div * MSSPLL_FIXED_DIV);
}

static const struct clk_ops mpfs_clk_msspll_ops = {
        .recalc_rate = mpfs_clk_msspll_recalc_rate,
};

#define CLK_PLL(_id, _name, _parent, _shift, _width, _flags, _offset) {                 \
        .id = _id,                                                                      \
        .flags = _flags,                                                                \
        .shift = _shift,                                                                \
        .width = _width,                                                                \
        .reg_offset = _offset,                                                          \
        .hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_msspll_ops, 0),   \
}

static struct mpfs_msspll_hw_clock mpfs_msspll_clks[] = {
        CLK_PLL(CLK_MSSPLL_INTERNAL, "clk_msspll_internal", mpfs_ext_ref, MSSPLL_FBDIV_SHIFT,
                MSSPLL_FBDIV_WIDTH, 0, REG_MSSPLL_SSCG_2_CR),
};

static int mpfs_clk_register_mssplls(struct device *dev, struct mpfs_msspll_hw_clock *msspll_hws,
                                     unsigned int num_clks, struct mpfs_clock_data *data)
{
        unsigned int i;
        int ret;

        for (i = 0; i < num_clks; i++) {
                struct mpfs_msspll_hw_clock *msspll_hw = &msspll_hws[i];

                msspll_hw->base = data->msspll_base;
                ret = devm_clk_hw_register(dev, &msspll_hw->hw);
                if (ret)
                        return dev_err_probe(dev, ret, "failed to register msspll id: %d\n",
                                             CLK_MSSPLL_INTERNAL);

                data->hw_data.hws[msspll_hw->id] = &msspll_hw->hw;
        }

        return 0;
}

/*
 * MSS PLL output clocks
 */

#define CLK_PLL_OUT(_id, _name, _parent, _flags, _shift, _width, _offset) {     \
        .id = _id,                                                              \
        .output.shift = _shift,                                                 \
        .output.width = _width,                                                 \
        .output.table = NULL,                                                   \
        .reg_offset = _offset,                                                  \
        .output.flags = _flags,                                                 \
        .output.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0),     \
        .output.lock = &mpfs_clk_lock,                                          \
}

static struct mpfs_msspll_out_hw_clock mpfs_msspll_out_clks[] = {
        CLK_PLL_OUT(CLK_MSSPLL0, "clk_msspll", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
                    MSSPLL_POSTDIV02_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV01_CR),
        CLK_PLL_OUT(CLK_MSSPLL1, "clk_msspll1", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
                    MSSPLL_POSTDIV13_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV01_CR),
        CLK_PLL_OUT(CLK_MSSPLL2, "clk_msspll2", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
                    MSSPLL_POSTDIV02_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV23_CR),
        CLK_PLL_OUT(CLK_MSSPLL3, "clk_msspll3", "clk_msspll_internal", CLK_DIVIDER_ONE_BASED,
                    MSSPLL_POSTDIV13_SHIFT, MSSPLL_POSTDIV_WIDTH, REG_MSSPLL_POSTDIV23_CR),
};

static int mpfs_clk_register_msspll_outs(struct device *dev,
                                         struct mpfs_msspll_out_hw_clock *msspll_out_hws,
                                         unsigned int num_clks, struct mpfs_clock_data *data)
{
        unsigned int i;
        int ret;

        for (i = 0; i < num_clks; i++) {
                struct mpfs_msspll_out_hw_clock *msspll_out_hw = &msspll_out_hws[i];

                msspll_out_hw->output.reg = data->msspll_base + msspll_out_hw->reg_offset;
                ret = devm_clk_hw_register(dev, &msspll_out_hw->output.hw);
                if (ret)
                        return dev_err_probe(dev, ret, "failed to register msspll out id: %d\n",
                                             msspll_out_hw->id);

                data->hw_data.hws[msspll_out_hw->id] = &msspll_out_hw->output.hw;
        }

        return 0;
}

/*
 * "CFG" clocks
 */

#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags, _offset) {         \
        .id = _id,                                                                      \
        .cfg.shift = _shift,                                                            \
        .cfg.width = _width,                                                            \
        .cfg.table = _table,                                                            \
        .reg_offset = _offset,                                                          \
        .cfg.flags = _flags,                                                            \
        .cfg.hw.init = CLK_HW_INIT(_name, _parent, &clk_divider_ops, 0),                \
        .cfg.lock = &mpfs_clk_lock,                                                     \
}

#define CLK_CPU_OFFSET          0u
#define CLK_AXI_OFFSET          1u
#define CLK_AHB_OFFSET          2u
#define CLK_RTCREF_OFFSET       3u

static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
        CLK_CFG(CLK_CPU, "clk_cpu", "clk_msspll", 0, 2, mpfs_div_cpu_axi_table, 0,
                REG_CLOCK_CONFIG_CR),
        CLK_CFG(CLK_AXI, "clk_axi", "clk_msspll", 2, 2, mpfs_div_cpu_axi_table, 0,
                REG_CLOCK_CONFIG_CR),
        CLK_CFG(CLK_AHB, "clk_ahb", "clk_msspll", 4, 2, mpfs_div_ahb_table, 0,
                REG_CLOCK_CONFIG_CR),
        {
                .id = CLK_RTCREF,
                .cfg.shift = 0,
                .cfg.width = 12,
                .cfg.table = mpfs_div_rtcref_table,
                .reg_offset = REG_RTC_CLOCK_CR,
                .cfg.flags = CLK_DIVIDER_ONE_BASED,
                .cfg.hw.init =
                        CLK_HW_INIT_PARENTS_DATA("clk_rtcref", mpfs_ext_ref, &clk_divider_ops, 0),
        }
};

static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
                                  unsigned int num_clks, struct mpfs_clock_data *data)
{
        unsigned int i, id;
        int ret;

        for (i = 0; i < num_clks; i++) {
                struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];

                cfg_hw->cfg.reg = data->base + cfg_hw->reg_offset;
                ret = devm_clk_hw_register(dev, &cfg_hw->cfg.hw);
                if (ret)
                        return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
                                             cfg_hw->id);

                id = cfg_hw->id;
                data->hw_data.hws[id] = &cfg_hw->cfg.hw;
        }

        return 0;
}

/*
 * peripheral clocks - devices connected to axi or ahb buses.
 */

#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) {                       \
        .id = _id,                                                              \
        .periph.bit_idx = _shift,                                               \
        .periph.hw.init = CLK_HW_INIT_HW(_name, _parent, &clk_gate_ops,         \
                                  _flags),                                      \
        .periph.lock = &mpfs_clk_lock,                                          \
}

#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT##_OFFSET].cfg.hw)

/*
 * Critical clocks:
 * - CLK_ENVM: reserved by hart software services (hss) superloop monitor/m mode interrupt
 *   trap handler
 * - CLK_MMUART0: reserved by the hss
 * - CLK_DDRC: provides clock to the ddr subsystem
 * - CLK_RTC: the onboard RTC's AHB bus clock must be kept running as the rtc will stop
 *   if the AHB interface clock is disabled
 * - CLK_FICx: these provide the processor side clocks to the "FIC" (Fabric InterConnect)
 *   clock domain crossers which provide the interface to the FPGA fabric. Disabling them
 *   causes the FPGA fabric to go into reset.
 * - CLK_ATHENA: The athena clock is FIC4, which is reserved for the Athena TeraFire.
 */

static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
        CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
        CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
        CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
        CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(RTCREF), 4, 0),
        CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
        CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
        CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
        CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
        CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
        CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
        CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
        CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
        CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
        CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
        CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
        CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
        CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
        CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
        CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
        CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AXI), 24, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AXI), 25, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AXI), 26, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AXI), 27, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AXI), 28, CLK_IS_CRITICAL),
        CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
};

static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
                                     int num_clks, struct mpfs_clock_data *data)
{
        unsigned int i, id;
        int ret;

        for (i = 0; i < num_clks; i++) {
                struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];

                periph_hw->periph.reg = data->base + REG_SUBBLK_CLOCK_CR;
                ret = devm_clk_hw_register(dev, &periph_hw->periph.hw);
                if (ret)
                        return dev_err_probe(dev, ret, "failed to register clock id: %d\n",
                                             periph_hw->id);

                id = periph_hws[i].id;
                data->hw_data.hws[id] = &periph_hw->periph.hw;
        }

        return 0;
}

static int mpfs_clk_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct mpfs_clock_data *clk_data;
        unsigned int num_clks;
        int ret;

        /* CLK_RESERVED is not part of clock arrays, so add 1 */
        num_clks = ARRAY_SIZE(mpfs_msspll_clks) + ARRAY_SIZE(mpfs_msspll_out_clks)
                   + ARRAY_SIZE(mpfs_cfg_clks)  + ARRAY_SIZE(mpfs_periph_clks) + 1;

        clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
        if (!clk_data)
                return -ENOMEM;

        clk_data->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(clk_data->base))
                return PTR_ERR(clk_data->base);

        clk_data->msspll_base = devm_platform_ioremap_resource(pdev, 1);
        if (IS_ERR(clk_data->msspll_base))
                return PTR_ERR(clk_data->msspll_base);

        clk_data->hw_data.num = num_clks;
        clk_data->dev = dev;
        dev_set_drvdata(dev, clk_data);

        ret = mpfs_clk_register_mssplls(dev, mpfs_msspll_clks, ARRAY_SIZE(mpfs_msspll_clks),
                                        clk_data);
        if (ret)
                return ret;

        ret = mpfs_clk_register_msspll_outs(dev, mpfs_msspll_out_clks,
                                            ARRAY_SIZE(mpfs_msspll_out_clks),
                                            clk_data);
        if (ret)
                return ret;

        ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
        if (ret)
                return ret;

        ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
                                        clk_data);
        if (ret)
                return ret;

        ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
        if (ret)
                return ret;

        return mpfs_reset_controller_register(dev, clk_data->base + REG_SUBBLK_RESET_CR);
}

static const struct of_device_id mpfs_clk_of_match_table[] = {
        { .compatible = "microchip,mpfs-clkcfg", },
        {}
};
MODULE_DEVICE_TABLE(of, mpfs_clk_of_match_table);

static struct platform_driver mpfs_clk_driver = {
        .probe = mpfs_clk_probe,
        .driver = {
                .name = "microchip-mpfs-clkcfg",
                .of_match_table = mpfs_clk_of_match_table,
        },
};

static int __init clk_mpfs_init(void)
{
        return platform_driver_register(&mpfs_clk_driver);
}
core_initcall(clk_mpfs_init);

static void __exit clk_mpfs_exit(void)
{
        platform_driver_unregister(&mpfs_clk_driver);
}
module_exit(clk_mpfs_exit);

MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
MODULE_AUTHOR("Padmarao Begari <padmarao.begari@microchip.com>");
MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
MODULE_IMPORT_NS("MCHP_CLK_MPFS");