// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2018, The Linux Foundation. All rights reserved.
 */

#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/clk-provider.h>
#include <linux/regmap.h>
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/soc/qcom/smem.h>

#include <dt-bindings/clock/qcom,apss-ipq.h>
#include <dt-bindings/arm/qcom,ids.h>

#include "common.h"
#include "clk-regmap.h"
#include "clk-branch.h"
#include "clk-alpha-pll.h"
#include "clk-rcg.h"

enum {
        P_XO,
        P_GPLL0,
        P_APSS_PLL_EARLY,
};

static const struct clk_parent_data parents_apcs_alias0_clk_src[] = {
        { .fw_name = "xo" },
        { .fw_name = "gpll0" },
        { .fw_name = "pll" },
};

static const struct parent_map parents_apcs_alias0_clk_src_map[] = {
        { P_XO, 0 },
        { P_GPLL0, 4 },
        { P_APSS_PLL_EARLY, 5 },
};

static struct clk_rcg2 apcs_alias0_clk_src = {
        .cmd_rcgr = 0x0050,
        .hid_width = 5,
        .parent_map = parents_apcs_alias0_clk_src_map,
        .clkr.hw.init = &(struct clk_init_data){
                .name = "apcs_alias0_clk_src",
                .parent_data = parents_apcs_alias0_clk_src,
                .num_parents = ARRAY_SIZE(parents_apcs_alias0_clk_src),
                .ops = &clk_rcg2_mux_closest_ops,
                .flags = CLK_SET_RATE_PARENT,
        },
};

static struct clk_branch apcs_alias0_core_clk = {
        .halt_reg = 0x0058,
        .clkr = {
                .enable_reg = 0x0058,
                .enable_mask = BIT(0),
                .hw.init = &(struct clk_init_data){
                        .name = "apcs_alias0_core_clk",
                        .parent_hws = (const struct clk_hw *[]){
                                &apcs_alias0_clk_src.clkr.hw },
                        .num_parents = 1,
                        .flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL,
                        .ops = &clk_branch2_ops,
                },
        },
};

static const struct regmap_config apss_ipq6018_regmap_config = {
        .reg_bits       = 32,
        .reg_stride     = 4,
        .val_bits       = 32,
        .max_register   = 0x1000,
        .fast_io        = true,
};

static struct clk_regmap *apss_ipq6018_clks[] = {
        [APCS_ALIAS0_CLK_SRC] = &apcs_alias0_clk_src.clkr,
        [APCS_ALIAS0_CORE_CLK] = &apcs_alias0_core_clk.clkr,
};

static const struct qcom_cc_desc apss_ipq6018_desc = {
        .config = &apss_ipq6018_regmap_config,
        .clks = apss_ipq6018_clks,
        .num_clks = ARRAY_SIZE(apss_ipq6018_clks),
};

static int cpu_clk_notifier_fn(struct notifier_block *nb, unsigned long action,
                                void *data)
{
        struct clk_hw *hw;
        u8 index;
        int err;

        if (action == PRE_RATE_CHANGE)
                index = P_GPLL0;
        else if (action == POST_RATE_CHANGE || action == ABORT_RATE_CHANGE)
                index = P_APSS_PLL_EARLY;
        else
                return NOTIFY_OK;

        hw = &apcs_alias0_clk_src.clkr.hw;
        err = clk_rcg2_mux_closest_ops.set_parent(hw, index);

        return notifier_from_errno(err);
}

static int apss_ipq6018_probe(struct platform_device *pdev)
{
        struct clk_hw *hw = &apcs_alias0_clk_src.clkr.hw;
        struct notifier_block *cpu_clk_notifier;
        struct regmap *regmap;
        u32 soc_id;
        int ret;

        ret = qcom_smem_get_soc_id(&soc_id);
        if (ret)
                return ret;

        regmap = dev_get_regmap(pdev->dev.parent, NULL);
        if (!regmap)
                return -ENODEV;

        ret = qcom_cc_really_probe(&pdev->dev, &apss_ipq6018_desc, regmap);
        if (ret)
                return ret;

        switch (soc_id) {
        /* Only below variants of IPQ53xx support scaling */
        case QCOM_ID_IPQ5332:
        case QCOM_ID_IPQ5322:
        case QCOM_ID_IPQ5300:
                cpu_clk_notifier = devm_kzalloc(&pdev->dev,
                                                sizeof(*cpu_clk_notifier),
                                                GFP_KERNEL);
                if (!cpu_clk_notifier)
                        return -ENOMEM;

                cpu_clk_notifier->notifier_call = cpu_clk_notifier_fn;

                ret = devm_clk_notifier_register(&pdev->dev, hw->clk, cpu_clk_notifier);
                if (ret)
                        return ret;
                break;
        default:
                break;
        }

        return 0;
}

static struct platform_driver apss_ipq6018_driver = {
        .probe = apss_ipq6018_probe,
        .driver = {
                .name   = "qcom,apss-ipq6018-clk",
        },
};

module_platform_driver(apss_ipq6018_driver);

MODULE_DESCRIPTION("QCOM APSS IPQ 6018 CLK Driver");
MODULE_LICENSE("GPL v2");