// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2011-2021, The Linux Foundation. All rights reserved.
 * Copyright (c) 2022-2025, Qualcomm Innovation Center, Inc. All rights reserved.
 */

#include <linux/bitfield.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>

#include <linux/soc/qcom/qcom_aoss.h>
#include <linux/soc/qcom/smem.h>
#include <clocksource/arm_arch_timer.h>

#define RPM_DYNAMIC_ADDR        0x14
#define RPM_DYNAMIC_ADDR_MASK   0xFFFF

#define STAT_TYPE_OFFSET        0x0
#define COUNT_OFFSET            0x4
#define LAST_ENTERED_AT_OFFSET  0x8
#define LAST_EXITED_AT_OFFSET   0x10
#define ACCUMULATED_OFFSET      0x18
#define CLIENT_VOTES_OFFSET     0x20

#define DDR_STATS_MAGIC_KEY             0xA1157A75
#define DDR_STATS_MAX_NUM_MODES         20
#define DDR_STATS_MAGIC_KEY_ADDR        0x0
#define DDR_STATS_NUM_MODES_ADDR        0x4
#define DDR_STATS_ENTRY_START_ADDR      0x8

#define DDR_STATS_CP_IDX(data)          FIELD_GET(GENMASK(4, 0), data)
#define DDR_STATS_LPM_NAME(data)        FIELD_GET(GENMASK(7, 0), data)
#define DDR_STATS_TYPE(data)            FIELD_GET(GENMASK(15, 8), data)
#define DDR_STATS_FREQ(data)            FIELD_GET(GENMASK(31, 16), data)

static struct qmp *qcom_stats_qmp;

struct subsystem_data {
        const char *name;
        u32 smem_item;
        u32 pid;
};

static const struct subsystem_data subsystems[] = {
        { "modem", 605, 1 },
        { "wpss", 605, 13 },
        { "adsp", 606, 2 },
        { "cdsp", 607, 5 },
        { "cdsp1", 607, 12 },
        { "gpdsp0", 607, 17 },
        { "gpdsp1", 607, 18 },
        { "slpi", 608, 3 },
        { "gpu", 609, 0 },
        { "display", 610, 0 },
        { "adsp_island", 613, 2 },
        { "slpi_island", 613, 3 },
        { "apss", 631, QCOM_SMEM_HOST_ANY },
};

struct stats_config {
        size_t stats_offset;
        size_t ddr_stats_offset;
        size_t num_records;
        bool appended_stats_avail;
        bool dynamic_offset;
        bool subsystem_stats_in_smem;
};

struct ddr_stats_entry {
        u32 name;
        u32 count;
        u64 duration;
};

struct stats_data {
        bool appended_stats_avail;
        void __iomem *base;
};

struct sleep_stats {
        u32 stat_type;
        u32 count;
        u64 last_entered_at;
        u64 last_exited_at;
        u64 accumulated;
};

struct appended_stats {
        u32 client_votes;
        u32 reserved[3];
};

static void qcom_print_stats(struct seq_file *s, const struct sleep_stats *stat)
{
        u64 accumulated = stat->accumulated;
        /*
         * If a subsystem is in sleep when reading the sleep stats adjust
         * the accumulated sleep duration to show actual sleep time.
         */
        if (stat->last_entered_at > stat->last_exited_at)
                accumulated += arch_timer_read_counter() - stat->last_entered_at;

        seq_printf(s, "Count: %u\n", stat->count);
        seq_printf(s, "Last Entered At: %llu\n", stat->last_entered_at);
        seq_printf(s, "Last Exited At: %llu\n", stat->last_exited_at);
        seq_printf(s, "Accumulated Duration: %llu\n", accumulated);
}

static int qcom_subsystem_sleep_stats_show(struct seq_file *s, void *unused)
{
        struct subsystem_data *subsystem = s->private;
        struct sleep_stats *stat;

        /* Items are allocated lazily, so lookup pointer each time */
        stat = qcom_smem_get(subsystem->pid, subsystem->smem_item, NULL);
        if (IS_ERR(stat))
                return 0;

        qcom_print_stats(s, stat);

        return 0;
}

static int qcom_soc_sleep_stats_show(struct seq_file *s, void *unused)
{
        struct stats_data *d = s->private;
        void __iomem *reg = d->base;
        struct sleep_stats stat;

        memcpy_fromio(&stat, reg, sizeof(stat));
        qcom_print_stats(s, &stat);

        if (d->appended_stats_avail) {
                struct appended_stats votes;

                memcpy_fromio(&votes, reg + CLIENT_VOTES_OFFSET, sizeof(votes));
                seq_printf(s, "Client Votes: %#x\n", votes.client_votes);
        }

        return 0;
}

static void qcom_ddr_stats_print(struct seq_file *s, struct ddr_stats_entry *data)
{
        u32 cp_idx;

        /*
         * DDR statistic have two different types of details encoded.
         * (1) DDR LPM Stats
         * (2) DDR Frequency Stats
         *
         * The name field have details like which type of DDR stat (bits 8:15)
         * along with other details as explained below
         *
         * In case of DDR LPM stat, name field will be encoded as,
         * Bits  -  Meaning
         * 0:7   -  DDR LPM name, can be of 0xd4, 0xd3, 0x11 and 0xd0.
         * 8:15  -  0x0 (indicates its a LPM stat)
         * 16:31 -  Unused
         *
         * In case of DDR FREQ stats, name field will be encoded as,
         * Bits  -  Meaning
         * 0:4   -  DDR Clock plan index (CP IDX)
         * 5:7   -  Unused
         * 8:15  -  0x1 (indicates its Freq stat)
         * 16:31 -  Frequency value in Mhz
         */
        switch (DDR_STATS_TYPE(data->name)) {
        case 0:
                seq_printf(s, "DDR LPM Stat Name:0x%lx\tcount:%u\tDuration (ticks):%llu\n",
                           DDR_STATS_LPM_NAME(data->name), data->count, data->duration);
                break;
        case 1:
                if (!data->count || !DDR_STATS_FREQ(data->name))
                        return;

                cp_idx = DDR_STATS_CP_IDX(data->name);
                seq_printf(s, "DDR Freq %luMhz:\tCP IDX:%u\tcount:%u\tDuration (ticks):%llu\n",
                           DDR_STATS_FREQ(data->name), cp_idx, data->count, data->duration);
                break;
        }
}

static int qcom_ddr_stats_show(struct seq_file *s, void *d)
{
        struct ddr_stats_entry data[DDR_STATS_MAX_NUM_MODES];
        void __iomem *reg = (void __iomem *)s->private;
        u32 entry_count;
        int i, ret;

        entry_count = readl_relaxed(reg + DDR_STATS_NUM_MODES_ADDR);
        if (entry_count > DDR_STATS_MAX_NUM_MODES)
                return -EINVAL;

        if (qcom_stats_qmp) {
                /*
                 * Recent SoCs (SM8450 onwards) do not have duration field
                 * populated from boot up onwards for both DDR LPM Stats
                 * and DDR Frequency Stats.
                 *
                 * Send QMP message to Always on processor which will
                 * populate duration field into MSG RAM area.
                 *
                 * Sent every time to read latest data.
                 */
                ret = qmp_send(qcom_stats_qmp, "{class: ddr, action: freqsync}");
                if (ret)
                        return ret;
        }

        reg += DDR_STATS_ENTRY_START_ADDR;
        memcpy_fromio(data, reg, sizeof(struct ddr_stats_entry) * entry_count);

        for (i = 0; i < entry_count; i++)
                qcom_ddr_stats_print(s, &data[i]);

        return 0;
}

DEFINE_SHOW_ATTRIBUTE(qcom_soc_sleep_stats);
DEFINE_SHOW_ATTRIBUTE(qcom_subsystem_sleep_stats);
DEFINE_SHOW_ATTRIBUTE(qcom_ddr_stats);

static void qcom_create_ddr_stat_files(struct dentry *root, void __iomem *reg,
                                       const struct stats_config *config)
{
        u32 key;

        if (!config->ddr_stats_offset)
                return;

        key = readl_relaxed(reg + config->ddr_stats_offset + DDR_STATS_MAGIC_KEY_ADDR);
        if (key == DDR_STATS_MAGIC_KEY)
                debugfs_create_file("ddr_stats", 0400, root,
                                    (__force void *)reg + config->ddr_stats_offset,
                                    &qcom_ddr_stats_fops);
}

static void qcom_create_soc_sleep_stat_files(struct dentry *root, void __iomem *reg,
                                             struct stats_data *d,
                                             const struct stats_config *config)
{
        char stat_type[sizeof(u32) + 1] = {0};
        size_t stats_offset = config->stats_offset;
        u32 offset = 0, type;
        int i, j;

        /*
         * On RPM targets, stats offset location is dynamic and changes from target
         * to target and sometimes from build to build for same target.
         *
         * In such cases the dynamic address is present at 0x14 offset from base
         * address in devicetree. The last 16bits indicates the stats_offset.
         */
        if (config->dynamic_offset) {
                stats_offset = readl(reg + RPM_DYNAMIC_ADDR);
                stats_offset &= RPM_DYNAMIC_ADDR_MASK;
        }

        for (i = 0; i < config->num_records; i++) {
                d[i].base = reg + offset + stats_offset;

                /*
                 * Read the low power mode name and create debugfs file for it.
                 * The names read could be of below,
                 * (may change depending on low power mode supported).
                 * For rpmh-sleep-stats: "aosd", "cxsd" and "ddr".
                 * For rpm-sleep-stats: "vmin" and "vlow".
                 */
                type = readl(d[i].base);
                for (j = 0; j < sizeof(u32); j++) {
                        stat_type[j] = type & 0xff;
                        type = type >> 8;
                }
                strim(stat_type);
                debugfs_create_file(stat_type, 0400, root, &d[i],
                                    &qcom_soc_sleep_stats_fops);

                offset += sizeof(struct sleep_stats);
                if (d[i].appended_stats_avail)
                        offset += sizeof(struct appended_stats);
        }
}

static void qcom_create_subsystem_stat_files(struct dentry *root,
                                             const struct stats_config *config)
{
        int i;

        if (!config->subsystem_stats_in_smem)
                return;

        for (i = 0; i < ARRAY_SIZE(subsystems); i++)
                debugfs_create_file(subsystems[i].name, 0400, root, (void *)&subsystems[i],
                                    &qcom_subsystem_sleep_stats_fops);
}

static int qcom_stats_probe(struct platform_device *pdev)
{
        void __iomem *reg;
        struct dentry *root;
        const struct stats_config *config;
        struct stats_data *d;
        int i;

        config = device_get_match_data(&pdev->dev);
        if (!config)
                return -ENODEV;

        reg = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
        if (IS_ERR(reg))
                return -ENOMEM;

        d = devm_kcalloc(&pdev->dev, config->num_records,
                         sizeof(*d), GFP_KERNEL);
        if (!d)
                return -ENOMEM;

        for (i = 0; i < config->num_records; i++)
                d[i].appended_stats_avail = config->appended_stats_avail;
        /*
         * QMP is used for DDR stats syncing to MSG RAM for recent SoCs (SM8450 onwards).
         * The prior SoCs do not need QMP handle as the required stats are already present
         * in MSG RAM, provided the DDR_STATS_MAGIC_KEY matches.
         */
        qcom_stats_qmp = qmp_get(&pdev->dev);
        if (IS_ERR(qcom_stats_qmp)) {
                /* We ignore error if QMP is not defined/needed */
                if (!of_property_present(pdev->dev.of_node, "qcom,qmp"))
                        qcom_stats_qmp = NULL;
                else if (PTR_ERR(qcom_stats_qmp) == -EPROBE_DEFER)
                        return -EPROBE_DEFER;
                else
                        return PTR_ERR(qcom_stats_qmp);
        }

        root = debugfs_create_dir("qcom_stats", NULL);

        qcom_create_subsystem_stat_files(root, config);
        qcom_create_soc_sleep_stat_files(root, reg, d, config);
        qcom_create_ddr_stat_files(root, reg, config);

        platform_set_drvdata(pdev, root);

        device_set_pm_not_required(&pdev->dev);

        return 0;
}

static void qcom_stats_remove(struct platform_device *pdev)
{
        struct dentry *root = platform_get_drvdata(pdev);

        debugfs_remove_recursive(root);
}

static const struct stats_config rpm_data = {
        .stats_offset = 0,
        .num_records = 2,
        .appended_stats_avail = true,
        .dynamic_offset = true,
        .subsystem_stats_in_smem = false,
};

/* Older RPM firmwares have the stats at a fixed offset instead */
static const struct stats_config rpm_data_dba0 = {
        .stats_offset = 0xdba0,
        .num_records = 2,
        .appended_stats_avail = true,
        .dynamic_offset = false,
        .subsystem_stats_in_smem = false,
};

static const struct stats_config rpmh_data_sdm845 = {
        .stats_offset = 0x48,
        .num_records = 2,
        .appended_stats_avail = false,
        .dynamic_offset = false,
        .subsystem_stats_in_smem = true,
};

static const struct stats_config rpmh_data = {
        .stats_offset = 0x48,
        .ddr_stats_offset = 0xb8,
        .num_records = 3,
        .appended_stats_avail = false,
        .dynamic_offset = false,
        .subsystem_stats_in_smem = true,
};

static const struct of_device_id qcom_stats_table[] = {
        { .compatible = "qcom,apq8084-rpm-stats", .data = &rpm_data_dba0 },
        { .compatible = "qcom,msm8226-rpm-stats", .data = &rpm_data_dba0 },
        { .compatible = "qcom,msm8916-rpm-stats", .data = &rpm_data_dba0 },
        { .compatible = "qcom,msm8974-rpm-stats", .data = &rpm_data_dba0 },
        { .compatible = "qcom,rpm-stats", .data = &rpm_data },
        { .compatible = "qcom,rpmh-stats", .data = &rpmh_data },
        { .compatible = "qcom,sdm845-rpmh-stats", .data = &rpmh_data_sdm845 },
        { }
};
MODULE_DEVICE_TABLE(of, qcom_stats_table);

static struct platform_driver qcom_stats = {
        .probe = qcom_stats_probe,
        .remove = qcom_stats_remove,
        .driver = {
                .name = "qcom_stats",
                .of_match_table = qcom_stats_table,
        },
};

static int __init qcom_stats_init(void)
{
        return platform_driver_register(&qcom_stats);
}
late_initcall(qcom_stats_init);

static void __exit qcom_stats_exit(void)
{
        platform_driver_unregister(&qcom_stats);
}
module_exit(qcom_stats_exit)

MODULE_DESCRIPTION("Qualcomm Technologies, Inc. (QTI) Stats driver");
MODULE_LICENSE("GPL v2");