[PATCH v3 5/6] perf: hisi: Add support for HiSilicon SoC DDRC PMU driver

[Shaokun Zhang]

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.

Signed-off-by: Shaokun Zhang <zhangshaokun@xxxxxxxxxxxxx>
Signed-off-by: Anurup M <anurup.m@xxxxxxxxxx>
---
 drivers/perf/hisilicon/Makefile               |   2 +-
 drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c | 437 ++++++++++++++++++++++++++
 2 files changed, 438 insertions(+), 1 deletion(-)
 create mode 100644 drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c

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..f362835
--- /dev/null
+++ b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c
@@ -0,0 +1,437 @@
+/*
+ * HiSilicon SoC DDRC uncore Hardware event counters support
+ *
+ * Copyright (C) 2017 Hisilicon Limited
+ * Author: Shaokun Zhang <zhangshaokun@xxxxxxxxxxxxx>
+ *         Anurup M <anurup.m@xxxxxxxxxx>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/acpi.h>
+#include <linux/bitmap.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/perf_event.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->scl_id)) {
+		dev_err(dev, "Can not read ddrc scl-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 struct attribute *hisi_ddrc_pmu_attrs[] = {
+	NULL,
+};
+
+static const struct attribute_group hisi_ddrc_pmu_attr_group = {
+	.attrs = hisi_ddrc_pmu_attrs,
+};
+
+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_attr_group,
+	&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->scl_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 hisi_pmu *ddrc_pmu;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	ddrc_pmu = hisi_pmu_alloc(dev, DDRC_NR_COUNTERS);
+	if (!ddrc_pmu)
+		return -ENOMEM;
+
+	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 = hisi_uncore_pmu_setup(ddrc_pmu, ddrc_pmu->name);
+	if (ret) {
+		dev_err(ddrc_pmu->dev, "hisi_uncore_pmu_setup failed!\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, ddrc_pmu);
+
+	return 0;
+}
+
+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, Anurup M");
-- 
1.9.1