// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2011-2021, The Linux Foundation. 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 DDR_DYNAMIC_OFFSET	0x1c
 #define DDR_OFFSET_MASK	GENMASK(9, 0)
#define CLIENT_VOTES_OFFSET	0x20

#define ARCH_TIMER_FREQ		19200000
#define DDR_MAGIC_KEY1		0xA1157A75 /* leetspeak "ALLSTATS" */
#define DDR_MAX_NUM_ENTRIES	20

#define DDR_VOTE_DRV_MAX	18
#define DDR_VOTE_DRV_ABSENT	0xdeaddead
#define DDR_VOTE_DRV_INVALID	0xffffdead
#define DDR_VOTE_X		GENMASK(27, 14)
#define DDR_VOTE_Y		GENMASK(13, 0)

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 },
	{ "slpi", 608, 3 },
	{ "gpu", 609, 0 },
	{ "display", 610, 0 },
	{ "adsp_island", 613, 2 },
	{ "slpi_island", 613, 3 },
};

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

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];
};

struct ddr_stats_entry {
	u32 name;
	u32 count;
	u64 dur;
} __packed;

struct ddr_stats {
	u32 key;
	u32 entry_count;
#define MAX_DDR_STAT_ENTRIES	20
	struct ddr_stats_entry entry[MAX_DDR_STAT_ENTRIES];
} __packed;

struct ddr_stats_data {
	struct device *dev;
	void __iomem *base;
	struct qmp *qmp;
};

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;
}

#define DDR_NAME_TYPE		GENMASK(15, 8)
 #define DDR_NAME_TYPE_LPM	0
 #define DDR_NAME_TYPE_FREQ	1

#define DDR_NAME_LPM_NAME	GENMASK(7, 0)

#define DDR_NAME_FREQ_MHZ	GENMASK(31, 16)
#define DDR_NAME_FREQ_CP_IDX	GENMASK(4, 0)
static void qcom_ddr_stats_print(struct seq_file *s, struct ddr_stats_entry *entry)
{
	u32 cp_idx, name;
	u8 type;

	type = FIELD_GET(DDR_NAME_TYPE, entry->name);

	switch (type) {
	case DDR_NAME_TYPE_LPM:
		name = FIELD_GET(DDR_NAME_LPM_NAME, entry->name);

		seq_printf(s, "LPM  | Type 0x%2x\tcount: %u\ttime: %llums\n",
			   name, entry->count, entry->dur);
		break;
	case DDR_NAME_TYPE_FREQ:
		cp_idx = FIELD_GET(DDR_NAME_FREQ_CP_IDX, entry->name);
		name = FIELD_GET(DDR_NAME_FREQ_MHZ, entry->name);

		/* Neither 0Mhz nor 0 votes is very interesting */
		if (!name || !entry->count)
			return;

		seq_printf(s, "Freq | %dMHz (idx %u)\tcount: %u\ttime: %llums\n",
			   name, cp_idx, entry->count, entry->dur);
		break;
	default:
		seq_printf(s, "Unknown data chunk (type = 0x%x count = 0x%x dur = 0x%llx)\n",
			   type, entry->count, entry->dur);
	}
}

static int qcom_ddr_stats_show(struct seq_file *s, void *unused)
{
	struct ddr_stats_data *ddrd = s->private;
	struct ddr_stats ddr;
	struct ddr_stats_entry *entry = ddr.entry;
	u32 entry_count, stats_size;
	u32 votes[DDR_VOTE_DRV_MAX];
	int i, ret;

	/* Request a stats sync, it may take some time to update though.. */
	ret = qmp_send(ddrd->qmp, "{class: ddr, action: freqsync}");
	if (ret) {
		dev_err(ddrd->dev, "failed to send QMP message\n");
		return ret;
	}

	entry_count = readl(ddrd->base + offsetof(struct ddr_stats, entry_count));
	if (entry_count > DDR_MAX_NUM_ENTRIES)
		return -EINVAL;

	/* We're not guaranteed to have DDR_MAX_NUM_ENTRIES */
	stats_size = sizeof(ddr);
	stats_size -= DDR_MAX_NUM_ENTRIES * sizeof(*entry);
	stats_size += entry_count * sizeof(*entry);

	/* Copy and process the stats */
	memcpy_fromio(&ddr, ddrd->base, stats_size);

	for (i = 0; i < ddr.entry_count; i++) {
		/* Convert the period to ms */
		entry[i].dur = div_u64(entry[i].dur, ARCH_TIMER_FREQ / MSEC_PER_SEC);
	}

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

	/* Ask AOSS to dump DDR votes */
	ret = qmp_send(ddrd->qmp, "{class: ddr, res: drvs_ddr_votes}");
	if (ret) {
		dev_err(ddrd->dev, "failed to send QMP message\n");
		return ret;
	}

	/* Subsystem votes */
	memcpy_fromio(votes, ddrd->base + stats_size, sizeof(u32) * DDR_VOTE_DRV_MAX);

	for (i = 0; i < DDR_VOTE_DRV_MAX; i++) {
		u32 ab, ib;

		if (votes[i] == DDR_VOTE_DRV_ABSENT || votes[i] == DDR_VOTE_DRV_INVALID)
			ab = ib = votes[i];
		else {
			ab = FIELD_GET(DDR_VOTE_X, votes[i]);
			ib = FIELD_GET(DDR_VOTE_Y, votes[i]);
		}

		seq_printf(s, "Vote | AB = %5u\tIB = %5u\n", ab, ib);
	}

	return 0;
}

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

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_create_ddr_stats_files(struct device *dev,
				       struct dentry *root,
				       void __iomem *reg,
				       const struct stats_config *config)
{
	struct ddr_stats_data *ddrd;
	u32 key, stats_offset;
	struct dentry *dent;

	/* Nothing to do */
	if (!config->ddr_stats)
		return 0;

	ddrd = devm_kzalloc(dev, sizeof(*ddrd), GFP_KERNEL);
	if (!ddrd)
		return dev_err_probe(dev, -ENOMEM, "Couldn't allocate DDR stats data\n");

	ddrd->dev = dev;

	/* Get the offset of DDR stats */
	stats_offset = readl(reg + DDR_DYNAMIC_OFFSET) & DDR_OFFSET_MASK;
	ddrd->base = reg + stats_offset;

	/* Check if DDR stats are present */
	key = readl(ddrd->base);
	if (key != DDR_MAGIC_KEY1)
		return 0;

	dent = debugfs_create_file("ddr_sleep_stats", 0400, root, ddrd, &qcom_ddr_stats_fops);
	if (IS_ERR(dent))
		return PTR_ERR(dent);

	/* QMP is only necessary for DDR votes */
	ddrd->qmp = qmp_get(dev);
	if (IS_ERR(ddrd->qmp)) {
		dev_err(dev, "Couldn't get QMP mailbox: %ld. DDR votes won't be available.\n",
			PTR_ERR(ddrd->qmp));
		debugfs_remove(dent);
	}

	return 0;
}

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, ret;

	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;

	root = debugfs_create_dir("qcom_stats", NULL);

	qcom_create_subsystem_stat_files(root, config);
	qcom_create_soc_sleep_stat_files(root, reg, d, config);
	ret = qcom_create_ddr_stats_files(&pdev->dev, root, reg, config);
	if (ret) {
		debugfs_remove_recursive(root);
		return ret;
	};

	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,
	.num_records = 3,
	.appended_stats_avail = false,
	.dynamic_offset = false,
	.subsystem_stats_in_smem = true,
	.ddr_stats = 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_new = 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");