Date: Tue, 15 Aug 2017 14:02:12 +0100
From: Mark Rutland <mark.rutland@arm.com>
To: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: will.deacon@arm.com, jonathan.cameron@huawei.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-doc@vger.kernel.org, linuxarm@huawei.com
Subject: Re: [PATCH v4 5/6] perf: hisi: Add support for HiSilicon SoC DDRC
 PMU driver
Message-ID: <20170815130211.GG6090@leverpostej>
References: <1500984642-204676-1-git-send-email-zhangshaokun@hisilicon.com>
 <1500984642-204676-6-git-send-email-zhangshaokun@hisilicon.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1500984642-204676-6-git-send-email-zhangshaokun@hisilicon.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 14246
Lines: 458

On Tue, Jul 25, 2017 at 08:10:41PM +0800, Shaokun Zhang wrote:
> This patch adds support for DDRC PMU driver in HiSilicon SoC chip, Each
> DDRC has own control, counter and interrupt registers and is an separate
> PMU. For each DDRC PMU, it has 8-fixed-purpose counters which have been
> mapped to 8-events by hardware, it assumes that counter index is equal
> to event code (0 - 7) in DDRC PMU driver. Interrupt is supported to
> handle counter (32-bits) overflow.
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
> Signed-off-by: Anurup M <anurup.m@huawei.com>
> ---
>  drivers/perf/hisilicon/Makefile               |   2 +-
>  drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c | 420 ++++++++++++++++++++++++++
>  2 files changed, 421 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c

My comments for the HHA PMU driver all apply here, too.

Thanks,
Mark.

> diff --git a/drivers/perf/hisilicon/Makefile b/drivers/perf/hisilicon/Makefile
> index a72afe8..2621d51 100644
> --- a/drivers/perf/hisilicon/Makefile
> +++ b/drivers/perf/hisilicon/Makefile
> @@ -1 +1 @@
> -obj-$(CONFIG_HISI_PMU) += hisi_uncore_pmu.o hisi_uncore_l3c_pmu.o hisi_uncore_hha_pmu.o
> +obj-$(CONFIG_HISI_PMU) += hisi_uncore_pmu.o hisi_uncore_l3c_pmu.o hisi_uncore_hha_pmu.o hisi_uncore_ddrc_pmu.o
> diff --git a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c
> new file mode 100644
> index 0000000..e178a09
> --- /dev/null
> +++ b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c
> @@ -0,0 +1,420 @@
> +/*
> + * HiSilicon SoC DDRC uncore Hardware event counters support
> + *
> + * Copyright (C) 2017 Hisilicon Limited
> + * Author: Shaokun Zhang <zhangshaokun@hisilicon.com>
> + *         Anurup M <anurup.m@huawei.com>
> + *
> + * This code is based on the uncore PMUs like arm-cci and arm-ccn.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +#include <linux/acpi.h>
> +#include <linux/bug.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/list.h>
> +#include <linux/platform_device.h>
> +#include "hisi_uncore_pmu.h"
> +
> +/* DDRC register definition */
> +#define DDRC_PERF_CTRL		0x010
> +#define DDRC_FLUX_WR		0x380
> +#define DDRC_FLUX_RD		0x384
> +#define DDRC_FLUX_WCMD          0x388
> +#define DDRC_FLUX_RCMD          0x38c
> +#define DDRC_PRE_CMD            0x3c0
> +#define DDRC_ACT_CMD            0x3c4
> +#define DDRC_BNK_CHG            0x3c8
> +#define DDRC_RNK_CHG            0x3cc
> +#define DDRC_EVENT_CTRL         0x6C0
> +#define DDRC_INT_MASK		0x6c8
> +#define DDRC_INT_STATUS		0x6cc
> +#define DDRC_INT_CLEAR		0x6d0
> +
> +/* DDRC supports 8-events and counter is fixed-purpose */
> +#define DDRC_NR_COUNTERS	0x8
> +#define DDRC_NR_EVENTS		DDRC_NR_COUNTERS
> +
> +#define DDRC_PERF_CTRL_EN	0x2
> +
> +/*
> + * For DDRC PMU, there are eight-events and every event has been mapped
> + * to fixed-purpose counters which register offset is not consistent.
> + * Therefore there is no write event type and we assume that event
> + * code (0 to 7) is equal to counter index in PMU driver.
> + */
> +#define GET_DDRC_EVENTID(hwc)	(hwc->config_base & 0x7)
> +
> +static const u32 ddrc_reg_off[] = {
> +	DDRC_FLUX_WR, DDRC_FLUX_RD, DDRC_FLUX_WCMD, DDRC_FLUX_RCMD,
> +	DDRC_PRE_CMD, DDRC_ACT_CMD, DDRC_BNK_CHG, DDRC_RNK_CHG
> +};
> +
> +/*
> + * Select the counter register offset using the counter index.
> + * In DDRC there are no programmable counter, the count
> + * is readed form the statistics counter register itself.
> + */
> +static u32 get_counter_reg_off(int cntr_idx)
> +{
> +	return ddrc_reg_off[cntr_idx];
> +}
> +
> +static u64 hisi_ddrc_pmu_read_counter(struct hisi_pmu *ddrc_pmu,
> +				      struct hw_perf_event *hwc)
> +{
> +	/* Use event code as counter index */
> +	u32 idx = GET_DDRC_EVENTID(hwc);
> +	u32 reg;
> +
> +	if (!hisi_uncore_pmu_counter_valid(ddrc_pmu, idx)) {
> +		dev_err(ddrc_pmu->dev, "Unsupported event index:%d!\n", idx);
> +		return 0;
> +	}
> +
> +	reg = get_counter_reg_off(idx);
> +
> +	return readl(ddrc_pmu->base + reg);
> +}
> +
> +static void hisi_ddrc_pmu_write_counter(struct hisi_pmu *ddrc_pmu,
> +					struct hw_perf_event *hwc, u64 val)
> +{
> +	u32 idx = GET_DDRC_EVENTID(hwc);
> +	u32 reg;
> +
> +	if (!hisi_uncore_pmu_counter_valid(ddrc_pmu, idx)) {
> +		dev_err(ddrc_pmu->dev, "Unsupported event index:%d!\n", idx);
> +		return;
> +	}
> +
> +	reg = get_counter_reg_off(idx);
> +	writel((u32)val, ddrc_pmu->base + reg);
> +}
> +
> +static void hisi_ddrc_pmu_start_counters(struct hisi_pmu *ddrc_pmu)
> +{
> +	u32 val;
> +
> +	/* Set perf_enable in DDRC_PERF_CTRL to start event counting */
> +	val = readl(ddrc_pmu->base + DDRC_PERF_CTRL);
> +	val |= DDRC_PERF_CTRL_EN;
> +	writel(val, ddrc_pmu->base + DDRC_PERF_CTRL);
> +}
> +
> +static void hisi_ddrc_pmu_stop_counters(struct hisi_pmu *ddrc_pmu)
> +{
> +	u32 val;
> +
> +	/* Clear perf_enable in DDRC_PERF_CTRL to stop event counting */
> +	val = readl(ddrc_pmu->base + DDRC_PERF_CTRL);
> +	val &= ~DDRC_PERF_CTRL_EN;
> +	writel(val, ddrc_pmu->base + DDRC_PERF_CTRL);
> +}
> +
> +static void hisi_ddrc_pmu_enable_counter(struct hisi_pmu *ddrc_pmu,
> +					 struct hw_perf_event *hwc)
> +{
> +	u32 val;
> +
> +	/* Set counter index(event code) in DDRC_EVENT_CTRL register */
> +	val = readl(ddrc_pmu->base + DDRC_EVENT_CTRL);
> +	val |= (1 << GET_DDRC_EVENTID(hwc));
> +	writel(val, ddrc_pmu->base + DDRC_EVENT_CTRL);
> +}
> +
> +static void hisi_ddrc_pmu_disable_counter(struct hisi_pmu *ddrc_pmu,
> +					  struct hw_perf_event *hwc)
> +{
> +	u32 val;
> +
> +	/* Clear counter index(event code) in DDRC_EVENT_CTRL register */
> +	val = readl(ddrc_pmu->base + DDRC_EVENT_CTRL);
> +	val &= ~(1 << GET_DDRC_EVENTID(hwc));
> +	writel(val, ddrc_pmu->base + DDRC_EVENT_CTRL);
> +}
> +
> +static int hisi_ddrc_pmu_get_event_idx(struct perf_event *event)
> +{
> +	struct hisi_pmu *ddrc_pmu = to_hisi_pmu(event->pmu);
> +	unsigned long *used_mask = ddrc_pmu->pmu_events.used_mask;
> +	struct hw_perf_event *hwc = &event->hw;
> +	/* For DDRC PMU, we use event code as counter index */
> +	int idx = GET_DDRC_EVENTID(hwc);
> +
> +	if (test_bit(idx, used_mask))
> +		return -EAGAIN;
> +
> +	set_bit(idx, used_mask);
> +
> +	return idx;
> +}
> +
> +static void hisi_ddrc_pmu_enable_counter_int(struct hisi_pmu *ddrc_pmu,
> +					     struct hw_perf_event *hwc)
> +{
> +	u32 val;
> +
> +	/* Write 0 to enable interrupt */
> +	val = readl(ddrc_pmu->base + DDRC_INT_MASK);
> +	val &= ~(1 << GET_DDRC_EVENTID(hwc));
> +	writel(val, ddrc_pmu->base + DDRC_INT_MASK);
> +}
> +
> +static void hisi_ddrc_pmu_disable_counter_int(struct hisi_pmu *ddrc_pmu,
> +					      struct hw_perf_event *hwc)
> +{
> +	u32 val;
> +
> +	/* Write 1 to mask interrupt */
> +	val = readl(ddrc_pmu->base + DDRC_INT_MASK);
> +	val |= (1 << GET_DDRC_EVENTID(hwc));
> +	writel(val, ddrc_pmu->base + DDRC_INT_MASK);
> +}
> +
> +static irqreturn_t hisi_ddrc_pmu_isr(int irq, void *dev_id)
> +{
> +	struct hisi_pmu *ddrc_pmu = dev_id;
> +	struct perf_event *event;
> +	unsigned long overflown;
> +	u32 status;
> +	int idx;
> +
> +	/* Read the DDRC_INT_STATUS register */
> +	status = readl(ddrc_pmu->base + DDRC_INT_STATUS);
> +	if (!status)
> +		return IRQ_NONE;
> +	overflown = status;
> +
> +	/*
> +	 * Find the counter index which overflowed if the bit was set
> +	 * and handle it
> +	 */
> +	for_each_set_bit(idx, &overflown, DDRC_NR_COUNTERS) {
> +		/* Write 1 to clear the IRQ status flag */
> +		writel((1 << idx), ddrc_pmu->base + DDRC_INT_CLEAR);
> +
> +		/* Get the corresponding event struct */
> +		event = ddrc_pmu->pmu_events.hw_events[idx];
> +		if (!event)
> +			continue;
> +
> +		hisi_uncore_pmu_event_update(event);
> +		hisi_uncore_pmu_set_event_period(event);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int hisi_ddrc_pmu_init_irq(struct hisi_pmu *ddrc_pmu,
> +				  struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	int irq, ret;
> +
> +	/* Read and init IRQ */
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_err(dev, "irq init: fail map DDRC overflow interrupt\n");
> +		return irq;
> +	}
> +
> +	ret = devm_request_irq(dev, irq, hisi_ddrc_pmu_isr,
> +			       IRQF_NOBALANCING | IRQF_NO_THREAD,
> +			       dev_name(dev), ddrc_pmu);
> +	if (ret < 0) {
> +		dev_err(dev, "Fail to request IRQ:%d ret:%d\n", irq, ret);
> +		return ret;
> +	}
> +
> +	/* Overflow interrupt also should use the same CPU */
> +	WARN_ON(irq_set_affinity(irq, &ddrc_pmu->cpus));
> +
> +	return 0;
> +}
> +
> +static const struct acpi_device_id hisi_ddrc_pmu_acpi_match[] = {
> +	{ "HISI0233", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(acpi, hisi_ddrc_pmu_acpi_match);
> +
> +static int hisi_ddrc_pmu_init_data(struct platform_device *pdev,
> +				   struct hisi_pmu *ddrc_pmu)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +
> +	/* Get the DDRC Channel ID */
> +	if (device_property_read_u32(dev, "hisilicon,ch-id",
> +				     &ddrc_pmu->ddrc_chn_id)) {
> +		dev_err(dev, "Can not read ddrc ch-id!\n");
> +		return -EINVAL;
> +	}
> +
> +	/* Get the DDRC SCCL ID */
> +	if (device_property_read_u32(dev, "hisilicon,scl-id",
> +				     &ddrc_pmu->sccl_id)) {
> +		dev_err(dev, "Can not read ddrc sccl-id!\n");
> +		return -EINVAL;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	ddrc_pmu->base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(ddrc_pmu->base)) {
> +		dev_err(dev, "ioremap failed for ddrc_pmu resource\n");
> +		return PTR_ERR(ddrc_pmu->base);
> +	}
> +
> +	return 0;
> +}
> +
> +static struct attribute *hisi_ddrc_pmu_format_attr[] = {
> +	HISI_PMU_FORMAT_ATTR(event, "config:0-4"),
> +	NULL,
> +};
> +
> +static const struct attribute_group hisi_ddrc_pmu_format_group = {
> +	.name = "format",
> +	.attrs = hisi_ddrc_pmu_format_attr,
> +};
> +
> +static struct attribute *hisi_ddrc_pmu_events_attr[] = {
> +	HISI_PMU_EVENT_ATTR(flux_wr,		0x00),
> +	HISI_PMU_EVENT_ATTR(flux_rd,		0x01),
> +	HISI_PMU_EVENT_ATTR(flux_wcmd,		0x02),
> +	HISI_PMU_EVENT_ATTR(flux_rcmd,		0x03),
> +	HISI_PMU_EVENT_ATTR(pre_cmd,		0x04),
> +	HISI_PMU_EVENT_ATTR(act_cmd,		0x05),
> +	HISI_PMU_EVENT_ATTR(rnk_chg,		0x06),
> +	HISI_PMU_EVENT_ATTR(rw_chg,		0x07),
> +	NULL,
> +};
> +
> +static const struct attribute_group hisi_ddrc_pmu_events_group = {
> +	.name = "events",
> +	.attrs = hisi_ddrc_pmu_events_attr,
> +};
> +
> +static DEVICE_ATTR(cpumask, 0444, hisi_cpumask_sysfs_show, NULL);
> +
> +static struct attribute *hisi_ddrc_pmu_cpumask_attrs[] = {
> +	&dev_attr_cpumask.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group hisi_ddrc_pmu_cpumask_attr_group = {
> +	.attrs = hisi_ddrc_pmu_cpumask_attrs,
> +};
> +
> +static const struct attribute_group *hisi_ddrc_pmu_attr_groups[] = {
> +	&hisi_ddrc_pmu_format_group,
> +	&hisi_ddrc_pmu_events_group,
> +	&hisi_ddrc_pmu_cpumask_attr_group,
> +	NULL,
> +};
> +
> +static const struct hisi_uncore_ops hisi_uncore_ddrc_ops = {
> +	.get_event_idx		= hisi_ddrc_pmu_get_event_idx,
> +	.start_counters		= hisi_ddrc_pmu_start_counters,
> +	.stop_counters		= hisi_ddrc_pmu_stop_counters,
> +	.enable_counter		= hisi_ddrc_pmu_enable_counter,
> +	.disable_counter	= hisi_ddrc_pmu_disable_counter,
> +	.enable_counter_int	= hisi_ddrc_pmu_enable_counter_int,
> +	.disable_counter_int	= hisi_ddrc_pmu_disable_counter_int,
> +	.write_counter		= hisi_ddrc_pmu_write_counter,
> +	.read_counter		= hisi_ddrc_pmu_read_counter,
> +};
> +
> +static int hisi_ddrc_pmu_dev_probe(struct platform_device *pdev,
> +				   struct hisi_pmu *ddrc_pmu)
> +{
> +	struct device *dev = &pdev->dev;
> +	int ret;
> +
> +	ret = hisi_ddrc_pmu_init_data(pdev, ddrc_pmu);
> +	if (ret)
> +		return ret;
> +
> +	/* Pick one core to use for cpumask attributes */
> +	cpumask_set_cpu(smp_processor_id(), &ddrc_pmu->cpus);
> +
> +	ret = hisi_ddrc_pmu_init_irq(ddrc_pmu, pdev);
> +	if (ret)
> +		return ret;
> +
> +	ddrc_pmu->name = devm_kasprintf(dev, GFP_KERNEL, "hisi_ddrc%u_%u",
> +					ddrc_pmu->ddrc_chn_id,
> +					ddrc_pmu->sccl_id);
> +	ddrc_pmu->num_events = DDRC_NR_EVENTS;
> +	ddrc_pmu->num_counters = DDRC_NR_COUNTERS;
> +	ddrc_pmu->counter_bits = 32;
> +	ddrc_pmu->ops = &hisi_uncore_ddrc_ops;
> +	ddrc_pmu->dev = dev;
> +
> +	return 0;
> +}
> +
> +static int hisi_ddrc_pmu_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct hisi_pmu *ddrc_pmu;
> +	int ret;
> +
> +	ddrc_pmu = hisi_pmu_alloc(dev, DDRC_NR_COUNTERS);
> +	if (!ddrc_pmu)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, ddrc_pmu);
> +
> +	ret = hisi_ddrc_pmu_dev_probe(pdev, ddrc_pmu);
> +	if (ret)
> +		return ret;
> +
> +	ddrc_pmu->pmu = (struct pmu) {
> +		.name		= ddrc_pmu->name,
> +		.task_ctx_nr	= perf_invalid_context,
> +		.event_init	= hisi_uncore_pmu_event_init,
> +		.pmu_enable	= hisi_uncore_pmu_enable,
> +		.pmu_disable	= hisi_uncore_pmu_disable,
> +		.add		= hisi_uncore_pmu_add,
> +		.del		= hisi_uncore_pmu_del,
> +		.start		= hisi_uncore_pmu_start,
> +		.stop		= hisi_uncore_pmu_stop,
> +		.read		= hisi_uncore_pmu_read,
> +		.attr_groups	= hisi_ddrc_pmu_attr_groups,
> +	};
> +
> +	ret = perf_pmu_register(&ddrc_pmu->pmu, ddrc_pmu->name, -1);
> +	if (ret)
> +		dev_err(ddrc_pmu->dev, "ddrc_pmu register failed!\n");
> +
> +	return ret;
> +}
> +
> +static int hisi_ddrc_pmu_remove(struct platform_device *pdev)
> +{
> +	struct hisi_pmu *ddrc_pmu = platform_get_drvdata(pdev);
> +
> +	perf_pmu_unregister(&ddrc_pmu->pmu);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver hisi_ddrc_pmu_driver = {
> +	.driver = {
> +		.name = "hisi_ddrc_pmu",
> +		.acpi_match_table = ACPI_PTR(hisi_ddrc_pmu_acpi_match),
> +	},
> +	.probe = hisi_ddrc_pmu_probe,
> +	.remove = hisi_ddrc_pmu_remove,
> +};
> +module_platform_driver(hisi_ddrc_pmu_driver);
> +
> +MODULE_DESCRIPTION("HiSilicon SoC DDRC uncore PMU driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Shaokun Zhang <zhangshaokun@hisilicon.com>");
> +MODULE_AUTHOR("Anurup M <anurup.m@huawei.com>");
> -- 
> 1.9.1
>