// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for HiSilicon Uncore NoC (Network on Chip) PMU device
 *
 * Copyright (c) 2025 HiSilicon Technologies Co., Ltd.
 * Author: Yicong Yang <yangyicong@hisilicon.com>
 */
#include <linux/bitops.h>
#include <linux/cpuhotplug.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/sysfs.h>

#include "hisi_uncore_pmu.h"

#define NOC_PMU_VERSION			0x1e00
#define NOC_PMU_GLOBAL_CTRL		0x1e04
#define   NOC_PMU_GLOBAL_CTRL_PMU_EN	BIT(0)
#define   NOC_PMU_GLOBAL_CTRL_TT_EN	BIT(1)
#define NOC_PMU_CNT_INFO		0x1e08
#define   NOC_PMU_CNT_INFO_OVERFLOW(n)	BIT(n)
#define NOC_PMU_EVENT_CTRL0		0x1e20
#define   NOC_PMU_EVENT_CTRL_TYPE	GENMASK(4, 0)
/*
 * Note channel of 0x0 will reset the counter value, so don't do it before
 * we read out the counter.
 */
#define   NOC_PMU_EVENT_CTRL_CHANNEL	GENMASK(10, 8)
#define   NOC_PMU_EVENT_CTRL_EN		BIT(11)
#define NOC_PMU_EVENT_COUNTER0		0x1e80

#define NOC_PMU_NR_COUNTERS		4
#define NOC_PMU_CH_DEFAULT		0x7

#define NOC_PMU_EVENT_CTRLn(ctrl0, n)	((ctrl0) + 4 * (n))
#define NOC_PMU_EVENT_CNTRn(cntr0, n)	((cntr0) + 8 * (n))

HISI_PMU_EVENT_ATTR_EXTRACTOR(ch, config1, 2, 0);
HISI_PMU_EVENT_ATTR_EXTRACTOR(tt_en, config1, 3, 3);

/* Dynamic CPU hotplug state used by this PMU driver */
static enum cpuhp_state hisi_noc_pmu_cpuhp_state;

struct hisi_noc_pmu_regs {
	u32 version;
	u32 pmu_ctrl;
	u32 event_ctrl0;
	u32 event_cntr0;
	u32 overflow_status;
};

/*
 * Tracetag filtering is not per event and all the events should keep
 * the consistence. Return true if the new comer doesn't match the
 * tracetag filtering configuration of the current scheduled events.
 */
static bool hisi_noc_pmu_check_global_filter(struct perf_event *curr,
					     struct perf_event *new)
{
	return hisi_get_tt_en(curr) == hisi_get_tt_en(new);
}

static void hisi_noc_pmu_write_evtype(struct hisi_pmu *noc_pmu, int idx, u32 type)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 reg;

	reg = readl(noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, idx));
	reg &= ~NOC_PMU_EVENT_CTRL_TYPE;
	reg |= FIELD_PREP(NOC_PMU_EVENT_CTRL_TYPE, type);
	writel(reg, noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, idx));
}

static int hisi_noc_pmu_get_event_idx(struct perf_event *event)
{
	struct hisi_pmu *noc_pmu = to_hisi_pmu(event->pmu);
	struct hisi_pmu_hwevents *pmu_events = &noc_pmu->pmu_events;
	int cur_idx;

	cur_idx = find_first_bit(pmu_events->used_mask, noc_pmu->num_counters);
	if (cur_idx != noc_pmu->num_counters &&
	    !hisi_noc_pmu_check_global_filter(pmu_events->hw_events[cur_idx], event))
		return -EAGAIN;

	return hisi_uncore_pmu_get_event_idx(event);
}

static u64 hisi_noc_pmu_read_counter(struct hisi_pmu *noc_pmu,
				     struct hw_perf_event *hwc)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;

	return readq(noc_pmu->base + NOC_PMU_EVENT_CNTRn(reg_info->event_cntr0, hwc->idx));
}

static void hisi_noc_pmu_write_counter(struct hisi_pmu *noc_pmu,
				       struct hw_perf_event *hwc, u64 val)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;

	writeq(val, noc_pmu->base + NOC_PMU_EVENT_CNTRn(reg_info->event_cntr0, hwc->idx));
}

static void hisi_noc_pmu_enable_counter(struct hisi_pmu *noc_pmu,
					struct hw_perf_event *hwc)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 reg;

	reg = readl(noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, hwc->idx));
	reg |= NOC_PMU_EVENT_CTRL_EN;
	writel(reg, noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, hwc->idx));
}

static void hisi_noc_pmu_disable_counter(struct hisi_pmu *noc_pmu,
					 struct hw_perf_event *hwc)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 reg;

	reg = readl(noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, hwc->idx));
	reg &= ~NOC_PMU_EVENT_CTRL_EN;
	writel(reg, noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, hwc->idx));
}

static void hisi_noc_pmu_enable_counter_int(struct hisi_pmu *noc_pmu,
					    struct hw_perf_event *hwc)
{
	/* We don't support interrupt, so a stub here. */
}

static void hisi_noc_pmu_disable_counter_int(struct hisi_pmu *noc_pmu,
					     struct hw_perf_event *hwc)
{
}

static void hisi_noc_pmu_start_counters(struct hisi_pmu *noc_pmu)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 reg;

	reg = readl(noc_pmu->base + reg_info->pmu_ctrl);
	reg |= NOC_PMU_GLOBAL_CTRL_PMU_EN;
	writel(reg, noc_pmu->base + reg_info->pmu_ctrl);
}

static void hisi_noc_pmu_stop_counters(struct hisi_pmu *noc_pmu)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 reg;

	reg = readl(noc_pmu->base + reg_info->pmu_ctrl);
	reg &= ~NOC_PMU_GLOBAL_CTRL_PMU_EN;
	writel(reg, noc_pmu->base + reg_info->pmu_ctrl);
}

static u32 hisi_noc_pmu_get_int_status(struct hisi_pmu *noc_pmu)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;

	return readl(noc_pmu->base + reg_info->overflow_status);
}

static void hisi_noc_pmu_clear_int_status(struct hisi_pmu *noc_pmu, int idx)
{
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 reg;

	reg = readl(noc_pmu->base + reg_info->overflow_status);
	reg &= ~NOC_PMU_CNT_INFO_OVERFLOW(idx);
	writel(reg, noc_pmu->base + reg_info->overflow_status);
}

static void hisi_noc_pmu_enable_filter(struct perf_event *event)
{
	struct hisi_pmu *noc_pmu = to_hisi_pmu(event->pmu);
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	struct hw_perf_event *hwc = &event->hw;
	u32 tt_en = hisi_get_tt_en(event);
	u32 ch = hisi_get_ch(event);
	u32 reg;

	if (!ch)
		ch = NOC_PMU_CH_DEFAULT;

	reg = readl(noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, hwc->idx));
	reg &= ~NOC_PMU_EVENT_CTRL_CHANNEL;
	reg |= FIELD_PREP(NOC_PMU_EVENT_CTRL_CHANNEL, ch);
	writel(reg, noc_pmu->base + NOC_PMU_EVENT_CTRLn(reg_info->event_ctrl0, hwc->idx));

	/*
	 * Since tracetag filter applies to all the counters, don't touch it
	 * if user doesn't specify it explicitly.
	 */
	if (tt_en) {
		reg = readl(noc_pmu->base + reg_info->pmu_ctrl);
		reg |= NOC_PMU_GLOBAL_CTRL_TT_EN;
		writel(reg, noc_pmu->base + reg_info->pmu_ctrl);
	}
}

static void hisi_noc_pmu_disable_filter(struct perf_event *event)
{
	struct hisi_pmu *noc_pmu = to_hisi_pmu(event->pmu);
	struct hisi_noc_pmu_regs *reg_info = noc_pmu->dev_info->private;
	u32 tt_en = hisi_get_tt_en(event);
	u32 reg;

	/*
	 * If we're not the last counter, don't touch the global tracetag
	 * configuration.
	 */
	if (bitmap_weight(noc_pmu->pmu_events.used_mask, noc_pmu->num_counters) > 1)
		return;

	if (tt_en) {
		reg = readl(noc_pmu->base + reg_info->pmu_ctrl);
		reg &= ~NOC_PMU_GLOBAL_CTRL_TT_EN;
		writel(reg, noc_pmu->base + reg_info->pmu_ctrl);
	}
}

static const struct hisi_uncore_ops hisi_uncore_noc_ops = {
	.write_evtype		= hisi_noc_pmu_write_evtype,
	.get_event_idx		= hisi_noc_pmu_get_event_idx,
	.read_counter		= hisi_noc_pmu_read_counter,
	.write_counter		= hisi_noc_pmu_write_counter,
	.enable_counter		= hisi_noc_pmu_enable_counter,
	.disable_counter	= hisi_noc_pmu_disable_counter,
	.enable_counter_int	= hisi_noc_pmu_enable_counter_int,
	.disable_counter_int	= hisi_noc_pmu_disable_counter_int,
	.start_counters		= hisi_noc_pmu_start_counters,
	.stop_counters		= hisi_noc_pmu_stop_counters,
	.get_int_status		= hisi_noc_pmu_get_int_status,
	.clear_int_status	= hisi_noc_pmu_clear_int_status,
	.enable_filter		= hisi_noc_pmu_enable_filter,
	.disable_filter		= hisi_noc_pmu_disable_filter,
};

static struct attribute *hisi_noc_pmu_format_attrs[] = {
	HISI_PMU_FORMAT_ATTR(event, "config:0-7"),
	HISI_PMU_FORMAT_ATTR(ch, "config1:0-2"),
	HISI_PMU_FORMAT_ATTR(tt_en, "config1:3"),
	NULL
};

static const struct attribute_group hisi_noc_pmu_format_group = {
	.name = "format",
	.attrs = hisi_noc_pmu_format_attrs,
};

static struct attribute *hisi_noc_pmu_events_attrs[] = {
	HISI_PMU_EVENT_ATTR(cycles, 0x0e),
	/* Flux on/off the ring */
	HISI_PMU_EVENT_ATTR(ingress_flow_sum, 0x1a),
	HISI_PMU_EVENT_ATTR(egress_flow_sum, 0x17),
	/* Buffer full duration on/off the ring */
	HISI_PMU_EVENT_ATTR(ingress_buf_full, 0x19),
	HISI_PMU_EVENT_ATTR(egress_buf_full, 0x12),
	/* Failure packets count on/off the ring */
	HISI_PMU_EVENT_ATTR(cw_ingress_fail, 0x01),
	HISI_PMU_EVENT_ATTR(cc_ingress_fail, 0x09),
	HISI_PMU_EVENT_ATTR(cw_egress_fail, 0x03),
	HISI_PMU_EVENT_ATTR(cc_egress_fail, 0x0b),
	/* Flux of the ring */
	HISI_PMU_EVENT_ATTR(cw_main_flow_sum, 0x05),
	HISI_PMU_EVENT_ATTR(cc_main_flow_sum, 0x0d),
	NULL
};

static const struct attribute_group hisi_noc_pmu_events_group = {
	.name = "events",
	.attrs = hisi_noc_pmu_events_attrs,
};

static const struct attribute_group *hisi_noc_pmu_attr_groups[] = {
	&hisi_noc_pmu_format_group,
	&hisi_noc_pmu_events_group,
	&hisi_pmu_cpumask_attr_group,
	&hisi_pmu_identifier_group,
	NULL
};

static int hisi_noc_pmu_dev_init(struct platform_device *pdev, struct hisi_pmu *noc_pmu)
{
	struct hisi_noc_pmu_regs *reg_info;

	hisi_uncore_pmu_init_topology(noc_pmu, &pdev->dev);

	if (noc_pmu->topo.scl_id < 0)
		return dev_err_probe(&pdev->dev, -EINVAL, "failed to get scl-id\n");

	if (noc_pmu->topo.index_id < 0)
		return dev_err_probe(&pdev->dev, -EINVAL, "failed to get idx-id\n");

	if (noc_pmu->topo.sub_id < 0)
		return dev_err_probe(&pdev->dev, -EINVAL, "failed to get sub-id\n");

	noc_pmu->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(noc_pmu->base))
		return dev_err_probe(&pdev->dev, PTR_ERR(noc_pmu->base),
				     "fail to remap io memory\n");

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

	noc_pmu->pmu_events.attr_groups = noc_pmu->dev_info->attr_groups;
	noc_pmu->counter_bits = noc_pmu->dev_info->counter_bits;
	noc_pmu->check_event = noc_pmu->dev_info->check_event;
	noc_pmu->num_counters = NOC_PMU_NR_COUNTERS;
	noc_pmu->ops = &hisi_uncore_noc_ops;
	noc_pmu->dev = &pdev->dev;
	noc_pmu->on_cpu = -1;

	reg_info = noc_pmu->dev_info->private;
	noc_pmu->identifier = readl(noc_pmu->base + reg_info->version);

	return 0;
}

static void hisi_noc_pmu_remove_cpuhp_instance(void *hotplug_node)
{
	cpuhp_state_remove_instance_nocalls(hisi_noc_pmu_cpuhp_state, hotplug_node);
}

static void hisi_noc_pmu_unregister_pmu(void *pmu)
{
	perf_pmu_unregister(pmu);
}

static int hisi_noc_pmu_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct hisi_pmu *noc_pmu;
	char *name;
	int ret;

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

	/*
	 * HiSilicon Uncore PMU framework needs to get common hisi_pmu device
	 * from device's drvdata.
	 */
	platform_set_drvdata(pdev, noc_pmu);

	ret = hisi_noc_pmu_dev_init(pdev, noc_pmu);
	if (ret)
		return ret;

	ret = cpuhp_state_add_instance(hisi_noc_pmu_cpuhp_state, &noc_pmu->node);
	if (ret)
		return dev_err_probe(dev, ret, "Fail to register cpuhp instance\n");

	ret = devm_add_action_or_reset(dev, hisi_noc_pmu_remove_cpuhp_instance,
				       &noc_pmu->node);
	if (ret)
		return ret;

	hisi_pmu_init(noc_pmu, THIS_MODULE);

	name = devm_kasprintf(dev, GFP_KERNEL, "hisi_scl%d_noc%d_%d",
			      noc_pmu->topo.scl_id, noc_pmu->topo.index_id,
			      noc_pmu->topo.sub_id);
	if (!name)
		return -ENOMEM;

	ret = perf_pmu_register(&noc_pmu->pmu, name, -1);
	if (ret)
		return dev_err_probe(dev, ret, "Fail to register PMU\n");

	return devm_add_action_or_reset(dev, hisi_noc_pmu_unregister_pmu,
					&noc_pmu->pmu);
}

static struct hisi_noc_pmu_regs hisi_noc_v1_pmu_regs = {
	.version = NOC_PMU_VERSION,
	.pmu_ctrl = NOC_PMU_GLOBAL_CTRL,
	.event_ctrl0 = NOC_PMU_EVENT_CTRL0,
	.event_cntr0 = NOC_PMU_EVENT_COUNTER0,
	.overflow_status = NOC_PMU_CNT_INFO,
};

static const struct hisi_pmu_dev_info hisi_noc_v1 = {
	.attr_groups = hisi_noc_pmu_attr_groups,
	.counter_bits = 64,
	.check_event = NOC_PMU_EVENT_CTRL_TYPE,
	.private = &hisi_noc_v1_pmu_regs,
};

static const struct acpi_device_id hisi_noc_pmu_ids[] = {
	{ "HISI04E0", (kernel_ulong_t) &hisi_noc_v1 },
	{ }
};
MODULE_DEVICE_TABLE(acpi, hisi_noc_pmu_ids);

static struct platform_driver hisi_noc_pmu_driver = {
	.driver = {
		.name = "hisi_noc_pmu",
		.acpi_match_table = hisi_noc_pmu_ids,
		.suppress_bind_attrs = true,
	},
	.probe = hisi_noc_pmu_probe,
};

static int __init hisi_noc_pmu_module_init(void)
{
	int ret;

	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "perf/hisi/noc:online",
				      hisi_uncore_pmu_online_cpu,
				      hisi_uncore_pmu_offline_cpu);
	if (ret < 0) {
		pr_err("hisi_noc_pmu: Fail to setup cpuhp callbacks, ret = %d\n", ret);
		return ret;
	}
	hisi_noc_pmu_cpuhp_state = ret;

	ret = platform_driver_register(&hisi_noc_pmu_driver);
	if (ret)
		cpuhp_remove_multi_state(hisi_noc_pmu_cpuhp_state);

	return ret;
}
module_init(hisi_noc_pmu_module_init);

static void __exit hisi_noc_pmu_module_exit(void)
{
	platform_driver_unregister(&hisi_noc_pmu_driver);
	cpuhp_remove_multi_state(hisi_noc_pmu_cpuhp_state);
}
module_exit(hisi_noc_pmu_module_exit);

MODULE_IMPORT_NS("HISI_PMU");
MODULE_DESCRIPTION("HiSilicon SoC Uncore NoC PMU driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>");