[PATCH v4 1/4] perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

[PATCH v4 1/4] perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

[Jiucheng Xu]

This patch adds support Amlogic meson G12 series SoC
DDR bandwidth PMU driver framework and interfaces.

The PMU not only can monitor the total DDR bandwidth,
but also the bandwidth which is from individual IP module.

Example usage:

 $ perf stat -a -e aml_ddr_bw/total_rw_bytes/ -I 1000 sleep 10

- or -

 $ perf stat -a -e \
   aml_ddr_bw/total_rw_bytes/,\
   aml_ddr_bw/chan_1_rw_bytes,arm=1/ -I 1000 \
   sleep 10

g12 SoC support 4 channels to monitor DDR bandwidth
simultaneously. Each channel can monitor up to 4 IP modules
simultaneously.

For Instance, If you want to get the sum of DDR bandwidth
from CPU, GPU, USB3.0 and VDEC. You can use the following
command parameters to display.

 $ perf stat -a -e \
   aml_ddr_bw/chan_2_rw_bytes,arm=1,gpu=1,usb3_0=1,nna=1/ -I 1000 \
   sleep 10

Other events are supported, and advertised via perf list.

Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
Reported-by: kernel test robot <lkp@intel.com>
---
Changes v3 -> v4:
  - No change

Changes v2 -> v3:
  - Fix sh GCC 12.1.0 compiling warning
  - Rename prefix aml to meson for files and code

Changes v1 -> v2:
  - Remove inline to let GCC make the decisions
  - Remove spinlock
  - Remove ddr_cnt_accumulate()
  - Remove the message which only indicate a bug
  - Remove all dev_warn() message
  - Use hweight64() helper instead of whole loop
  - Remove setting of hwc
  - Use for_each_set_bit() helper for bit loop
  - Use sysfs_emit() in sysfs show
  - Remove checking for bugs
  - Replace irq_set_affinity_hint() to irq_set_affinity()
  - Remove #ifdef CONFIG_OF
  - Use devm_platform_ioremap_resource() instead of
    platform_get_resource()&ioremap()
  - Use platform_get_irq() instead of platform_get_resource()&ioremap()
  - Replace IRQF_SHARED to IRQF_NOBALANCING
  - Remove meaningless log like "init ok"
  - Use compatible instead of creating new property to distinguish
    different platform.
  - Use the is_visible callback to avoid exposing unsupported fmt_attr
  - Use module_platform_driver_probe() instead of module_init/exit
---
 MAINTAINERS                               |   7 +
 drivers/perf/Kconfig                      |   2 +
 drivers/perf/Makefile                     |   1 +
 drivers/perf/amlogic/Kconfig              |  10 +
 drivers/perf/amlogic/Makefile             |   5 +
 drivers/perf/amlogic/meson_ddr_pmu_core.c | 544 ++++++++++++++++++++++
 drivers/perf/amlogic/meson_g12_ddr_pmu.c  | 388 +++++++++++++++
 include/soc/amlogic/meson_ddr_pmu.h       |  76 +++
 8 files changed, 1033 insertions(+)
 create mode 100644 drivers/perf/amlogic/Kconfig
 create mode 100644 drivers/perf/amlogic/Makefile
 create mode 100644 drivers/perf/amlogic/meson_ddr_pmu_core.c
 create mode 100644 drivers/perf/amlogic/meson_g12_ddr_pmu.c
 create mode 100644 include/soc/amlogic/meson_ddr_pmu.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 1d99d54fa881..ac8a98dfbacc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1050,6 +1050,13 @@ S:	Maintained
 F:	Documentation/hid/amd-sfh*
 F:	drivers/hid/amd-sfh-hid/
 
+AMLOGIC DDR PMU DRIVER
+M:	Jiucheng Xu <jiucheng.xu@amlogic.com>
+S:	Supported
+W:	http://www.amlogic.com
+F:	drivers/perf/amlogic/
+F:	include/soc/amlogic/
+
 AMPHION VPU CODEC V4L2 DRIVER
 M:	Ming Qian <ming.qian@nxp.com>
 M:	Shijie Qin <shijie.qin@nxp.com>
diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
index 1e2d69453771..68200c798128 100644
--- a/drivers/perf/Kconfig
+++ b/drivers/perf/Kconfig
@@ -192,4 +192,6 @@ config MARVELL_CN10K_DDR_PMU
 	  Enable perf support for Marvell DDR Performance monitoring
 	  event on CN10K platform.
 
+source "drivers/perf/amlogic/Kconfig"
+
 endmenu
diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
index 57a279c61df5..4930482a15ff 100644
--- a/drivers/perf/Makefile
+++ b/drivers/perf/Makefile
@@ -20,3 +20,4 @@ obj-$(CONFIG_ARM_DMC620_PMU) += arm_dmc620_pmu.o
 obj-$(CONFIG_MARVELL_CN10K_TAD_PMU) += marvell_cn10k_tad_pmu.o
 obj-$(CONFIG_MARVELL_CN10K_DDR_PMU) += marvell_cn10k_ddr_pmu.o
 obj-$(CONFIG_APPLE_M1_CPU_PMU) += apple_m1_cpu_pmu.o
+obj-$(CONFIG_MESON_DDR_PMU) += amlogic/
diff --git a/drivers/perf/amlogic/Kconfig b/drivers/perf/amlogic/Kconfig
new file mode 100644
index 000000000000..f68db01a7f17
--- /dev/null
+++ b/drivers/perf/amlogic/Kconfig
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config MESON_DDR_PMU
+	tristate "Amlogic DDR Bandwidth Performance Monitor"
+	depends on ARCH_MESON || COMPILE_TEST
+	help
+          Provides support for the DDR performance monitor
+          in Amlogic SoCs, which can give information about
+          memory throughput and other related events. It
+          supports multiple channels to monitor the memory
+          bandwidth simultaneously.
diff --git a/drivers/perf/amlogic/Makefile b/drivers/perf/amlogic/Makefile
new file mode 100644
index 000000000000..8dd892a25efa
--- /dev/null
+++ b/drivers/perf/amlogic/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_MESON_DDR_PMU) += meson_ddr_pmu.o
+
+meson_ddr_pmu-y	:= meson_ddr_pmu_core.o meson_g12_ddr_pmu.o
diff --git a/drivers/perf/amlogic/meson_ddr_pmu_core.c b/drivers/perf/amlogic/meson_ddr_pmu_core.c
new file mode 100644
index 000000000000..7a51b445f6df
--- /dev/null
+++ b/drivers/perf/amlogic/meson_ddr_pmu_core.c
@@ -0,0 +1,544 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
+ */
+#include <linux/bitfield.h>
+#include <linux/init.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/version.h>
+
+#include <soc/amlogic/meson_ddr_pmu.h>
+
+#define DDR_PERF_DEV_NAME "meson_ddr_bw"
+#define MAX_AXI_PORTS_OF_CHANNEL	4	/* A DMC channel can monitor max 4 axi ports */
+
+#define to_ddr_pmu(p)		container_of(p, struct ddr_pmu, pmu)
+
+#define hw_info_to_pmu(p)	container_of(p, struct ddr_pmu, info)
+
+static void dmc_pmu_enable(struct ddr_pmu *pmu)
+{
+	if (!pmu->pmu_enabled)
+		pmu->info.ops->enable(&pmu->info);
+
+	pmu->pmu_enabled = true;
+}
+
+static void dmc_pmu_disable(struct ddr_pmu *pmu)
+{
+	if (pmu->pmu_enabled)
+		pmu->info.ops->disable(&pmu->info);
+
+	pmu->pmu_enabled = false;
+}
+
+static void meson_ddr_config_axi_id(struct ddr_pmu *pmu, int axi_id, int chann)
+{
+	pmu->info.ops->config_axi_id(&pmu->info, axi_id, chann);
+}
+
+static void meson_ddr_set_filter(struct perf_event *event, u8 axi_id)
+{
+	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+	int chann;
+
+	if (event->attr.config > ALL_CHAN_COUNTER_ID &&
+	    event->attr.config < COUNTER_MAX_ID) {
+		chann = event->attr.config - CHAN1_COUNTER_ID;
+
+		meson_ddr_config_axi_id(pmu, axi_id, chann);
+	}
+}
+
+static void ddr_cnt_addition(struct dmc_counter *sum,
+			     struct dmc_counter *add1,
+			     struct dmc_counter *add2,
+			     int chann_nr)
+{
+	int i;
+	u64 cnt1, cnt2;
+
+	sum->all_cnt = add1->all_cnt + add2->all_cnt;
+	sum->all_req = add1->all_req + add2->all_req;
+	for (i = 0; i < chann_nr; i++) {
+		cnt1 = add1->channel_cnt[i];
+		cnt2 = add2->channel_cnt[i];
+
+		sum->channel_cnt[i] = cnt1 + cnt2;
+	}
+}
+
+static void meson_ddr_perf_event_update(struct perf_event *event)
+{
+	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+	u64 new_raw_count = 0;
+	struct dmc_counter dc = {0}, sum_dc = {0};
+	int idx;
+
+	/* get the remain counters in register. */
+	pmu->info.ops->get_counters(&pmu->info, &dc);
+
+	ddr_cnt_addition(&sum_dc, &pmu->counters, &dc, pmu->info.chann_nr);
+
+	switch (event->attr.config) {
+	case ALL_CHAN_COUNTER_ID:
+		new_raw_count = sum_dc.all_cnt;
+		break;
+	case CHAN1_COUNTER_ID:
+	case CHAN2_COUNTER_ID:
+	case CHAN3_COUNTER_ID:
+	case CHAN4_COUNTER_ID:
+	case CHAN5_COUNTER_ID:
+	case CHAN6_COUNTER_ID:
+	case CHAN7_COUNTER_ID:
+	case CHAN8_COUNTER_ID:
+		idx = event->attr.config - CHAN1_COUNTER_ID;
+		new_raw_count = sum_dc.channel_cnt[idx];
+		break;
+	}
+
+	local64_set(&event->count, new_raw_count);
+}
+
+static int meson_ddr_perf_event_init(struct perf_event *event)
+{
+	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+	u64 config1 = event->attr.config1;
+
+	if (event->attr.type != event->pmu->type)
+		return -ENOENT;
+
+	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+		return -EOPNOTSUPP;
+
+	if (event->cpu < 0)
+		return -EOPNOTSUPP;
+
+	/* check if the number of parameters is too much */
+	if (event->attr.config != ALL_CHAN_COUNTER_ID &&
+	    hweight64(config1) > MAX_AXI_PORTS_OF_CHANNEL)
+		return -EOPNOTSUPP;
+
+	event->cpu = pmu->cpu;
+
+	return 0;
+}
+
+static void meson_ddr_perf_event_start(struct perf_event *event, int flags)
+{
+	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+
+	memset(&pmu->counters, 0, sizeof(pmu->counters));
+	dmc_pmu_enable(pmu);
+}
+
+static int meson_ddr_perf_event_add(struct perf_event *event, int flags)
+{
+	u64 config1 = event->attr.config1;
+	int i;
+
+	for_each_set_bit(i, (const unsigned long *)&config1, sizeof(config1))
+		meson_ddr_set_filter(event, i);
+
+	if (flags & PERF_EF_START)
+		meson_ddr_perf_event_start(event, flags);
+
+	return 0;
+}
+
+static void meson_ddr_perf_event_stop(struct perf_event *event, int flags)
+{
+	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+
+	if (flags & PERF_EF_UPDATE)
+		meson_ddr_perf_event_update(event);
+
+	dmc_pmu_disable(pmu);
+}
+
+static void meson_ddr_perf_event_del(struct perf_event *event, int flags)
+{
+	meson_ddr_perf_event_stop(event, PERF_EF_UPDATE);
+}
+
+static ssize_t meson_ddr_perf_cpumask_show(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct ddr_pmu *pmu = dev_get_drvdata(dev);
+
+	return cpumap_print_to_pagebuf(true, buf, cpumask_of(pmu->cpu));
+}
+
+static struct device_attribute meson_ddr_perf_cpumask_attr =
+__ATTR(cpumask, 0444, meson_ddr_perf_cpumask_show, NULL);
+
+static struct attribute *meson_ddr_perf_cpumask_attrs[] = {
+	&meson_ddr_perf_cpumask_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ddr_perf_cpumask_attr_group = {
+	.attrs = meson_ddr_perf_cpumask_attrs,
+};
+
+static ssize_t
+pmu_event_show(struct device *dev, struct device_attribute *attr,
+	       char *page)
+{
+	struct perf_pmu_events_attr *pmu_attr;
+
+	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
+	return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
+}
+
+static ssize_t
+event_show_unit(struct device *dev, struct device_attribute *attr,
+		char *page)
+{
+	return sysfs_emit(page, "MB\n");
+}
+
+static ssize_t
+event_show_scale(struct device *dev, struct device_attribute *attr,
+		 char *page)
+{
+	/* one count = 16byte = 1.52587890625e-05 MB */
+	return sysfs_emit(page, "1.52587890625e-05\n");
+}
+
+#define AML_DDR_PMU_EVENT_ATTR(_name, _id)				\
+{									\
+	.attr = __ATTR(_name, 0444, pmu_event_show, NULL),		\
+	.id = _id,							\
+}
+
+#define AML_DDR_PMU_EVENT_UNIT_ATTR(_name)				\
+	__ATTR(_name.unit, 0444, event_show_unit, NULL)
+
+#define AML_DDR_PMU_EVENT_SCALE_ATTR(_name)				\
+	__ATTR(_name.scale, 0444, event_show_scale, NULL)
+
+static struct device_attribute event_unit_attrs[] = {
+	AML_DDR_PMU_EVENT_UNIT_ATTR(total_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_1_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_2_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_3_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_4_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_5_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_6_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_7_rw_bytes),
+	AML_DDR_PMU_EVENT_UNIT_ATTR(chan_8_rw_bytes),
+};
+
+static struct device_attribute event_scale_attrs[] = {
+	AML_DDR_PMU_EVENT_SCALE_ATTR(total_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_1_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_2_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_3_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_4_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_5_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_6_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_7_rw_bytes),
+	AML_DDR_PMU_EVENT_SCALE_ATTR(chan_8_rw_bytes),
+};
+
+static struct perf_pmu_events_attr event_attrs[] = {
+	AML_DDR_PMU_EVENT_ATTR(total_rw_bytes, ALL_CHAN_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_1_rw_bytes, CHAN1_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_2_rw_bytes, CHAN2_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_3_rw_bytes, CHAN3_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_4_rw_bytes, CHAN4_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_5_rw_bytes, CHAN5_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_6_rw_bytes, CHAN6_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_7_rw_bytes, CHAN7_COUNTER_ID),
+	AML_DDR_PMU_EVENT_ATTR(chan_8_rw_bytes, CHAN8_COUNTER_ID),
+};
+
+/* three attrs are combined an event */
+static struct attribute *ddr_perf_events_attrs[COUNTER_MAX_ID * 3];
+
+static struct attribute_group ddr_perf_events_attr_group = {
+	.name = "events",
+	.attrs = ddr_perf_events_attrs,
+};
+
+/* an attr represents axi id, the max id is less than 256 */
+static struct attribute *ddr_perf_format_attrs[256];
+
+static umode_t meson_ddr_perf_format_attr_visible(struct kobject *kobj,
+						  struct attribute *attr,
+						  int n)
+{
+	return attr->mode;
+}
+
+static struct attribute_group ddr_perf_format_attr_group = {
+	.name = "format",
+	.attrs = ddr_perf_format_attrs,
+	.is_visible = meson_ddr_perf_format_attr_visible,
+};
+
+static ssize_t meson_ddr_perf_identifier_show(struct device *dev,
+					      struct device_attribute *attr,
+					      char *page)
+{
+	struct ddr_pmu *pmu = dev_get_drvdata(dev);
+
+	return sysfs_emit(page, "%s\n", pmu->name);
+}
+
+static struct device_attribute meson_ddr_perf_identifier_attr =
+__ATTR(identifier, 0444, meson_ddr_perf_identifier_show, NULL);
+
+static struct attribute *meson_ddr_perf_identifier_attrs[] = {
+	&meson_ddr_perf_identifier_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ddr_perf_identifier_attr_group = {
+	.attrs = meson_ddr_perf_identifier_attrs,
+};
+
+static const struct attribute_group *attr_groups[] = {
+	&ddr_perf_events_attr_group,
+	&ddr_perf_format_attr_group,
+	&ddr_perf_cpumask_attr_group,
+	&ddr_perf_identifier_attr_group,
+	NULL,
+};
+
+static irqreturn_t dmc_irq_handler(int irq, void *dev_id)
+{
+	struct dmc_hw_info *info = dev_id;
+	struct ddr_pmu *pmu;
+	struct dmc_counter counters, *sum_cnter;
+	int i;
+
+	pmu = hw_info_to_pmu(info);
+
+	if (info->ops->irq_handler(info, &counters) != 0)
+		goto out;
+
+	sum_cnter = &pmu->counters;
+	sum_cnter->all_cnt += counters.all_cnt;
+	sum_cnter->all_req += counters.all_req;
+
+	for (i = 0; i < pmu->info.chann_nr; i++)
+		sum_cnter->channel_cnt[i] += counters.channel_cnt[i];
+
+	if (pmu->pmu_enabled)
+		/*
+		 * the timer interrupt only supprt
+		 * one shot mode, we have to re-enable
+		 * it in ISR to support continue mode.
+		 */
+		info->ops->enable(info);
+
+	dev_dbg(pmu->dev, "counts: %llu %llu %llu, %llu, %llu, %llu\t\t"
+			"sum: %llu %llu %llu, %llu, %llu, %llu\n",
+			counters.all_req,
+			counters.all_cnt,
+			counters.channel_cnt[0],
+			counters.channel_cnt[1],
+			counters.channel_cnt[2],
+			counters.channel_cnt[3],
+
+			pmu->counters.all_req,
+			pmu->counters.all_cnt,
+			pmu->counters.channel_cnt[0],
+			pmu->counters.channel_cnt[1],
+			pmu->counters.channel_cnt[2],
+			pmu->counters.channel_cnt[3]);
+out:
+	return IRQ_HANDLED;
+}
+
+static int ddr_perf_offline_cpu(unsigned int cpu, struct hlist_node *node)
+{
+	struct ddr_pmu *pmu = hlist_entry_safe(node, struct ddr_pmu, node);
+	int target;
+
+	if (cpu != pmu->cpu)
+		return 0;
+
+	target = cpumask_any_but(cpu_online_mask, cpu);
+	if (target >= nr_cpu_ids)
+		return 0;
+
+	perf_pmu_migrate_context(&pmu->pmu, cpu, target);
+	pmu->cpu = target;
+
+	WARN_ON(irq_set_affinity(pmu->info.irq_num, cpumask_of(pmu->cpu)));
+
+	return 0;
+}
+
+static void fill_event_attr(struct ddr_pmu *pmu)
+{
+	int i, j, k;
+	struct attribute **dst = ddr_perf_events_attrs;
+
+	j = 0;
+	k = 0;
+
+	/* fill ALL_CHAN_COUNTER_ID event */
+	dst[j++] = &event_attrs[k].attr.attr;
+	dst[j++] = &event_unit_attrs[k].attr;
+	dst[j++] = &event_scale_attrs[k].attr;
+
+	k++;
+
+	/* fill each channel event */
+	for (i = 0; i < pmu->info.chann_nr; i++, k++) {
+		dst[j++] = &event_attrs[k].attr.attr;
+		dst[j++] = &event_unit_attrs[k].attr;
+		dst[j++] = &event_scale_attrs[k].attr;
+	}
+
+	dst[j] = NULL; /* mark end */
+}
+
+static void fmt_attr_fill(struct attribute **fmt_attr)
+{
+	int i;
+
+	for (i = 0; fmt_attr[i]; i++)
+		ddr_perf_format_attrs[i] = fmt_attr[i];
+
+	ddr_perf_format_attrs[i] = NULL;
+}
+
+static int ddr_pmu_parse_dt(struct platform_device *pdev, struct dmc_hw_info *info)
+{
+	/*struct pinctrl *p;*/
+	void __iomem *base;
+	int i, ret = -EINVAL;
+
+	for (i = 0; i < info->dmc_nr; i++) {
+		/* resource 0 for ddr register base */
+		base = devm_platform_ioremap_resource(pdev, i);
+		if (IS_ERR(base)) {
+			dev_err(&pdev->dev, "couldn't ioremap ddr reg %d\n", i);
+			return PTR_ERR(base);
+		}
+		info->ddr_reg[i] = base;
+	}
+
+	/* resource i for pll register base */
+	base = devm_platform_ioremap_resource(pdev, i);
+	if (IS_ERR(base)) {
+		dev_err(&pdev->dev, "couldn't ioremap for pll reg\n");
+		return PTR_ERR(base);
+	}
+	info->pll_reg = base;
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "couldn't get irq\n");
+		return ret;
+	}
+	info->irq_num = ret;
+
+	ret = devm_request_irq(&pdev->dev, info->irq_num, dmc_irq_handler,
+			       IRQF_NOBALANCING, dev_name(&pdev->dev),
+			       (void *)info);
+	if (ret < 0)
+		dev_err(&pdev->dev, "ddr request irq failed\n");
+
+	return ret;
+}
+
+int meson_ddr_pmu_create(struct platform_device *pdev, struct ddr_pmu *pmu)
+{
+	int ret;
+	char *name;
+	struct pmu tmp_pmu = {
+		.module		= THIS_MODULE,
+		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
+		.task_ctx_nr	= perf_invalid_context,
+		.attr_groups	= attr_groups,
+		.event_init	= meson_ddr_perf_event_init,
+		.add		= meson_ddr_perf_event_add,
+		.del		= meson_ddr_perf_event_del,
+		.start		= meson_ddr_perf_event_start,
+		.stop		= meson_ddr_perf_event_stop,
+		.read		= meson_ddr_perf_event_update,
+	};
+
+	pmu->pmu = tmp_pmu;
+
+	ret = ddr_pmu_parse_dt(pdev, &pmu->info);
+	if (ret < 0)
+		return ret;
+
+	fmt_attr_fill(pmu->info.fmt_attr);
+
+	pmu->cpu = raw_smp_processor_id();
+
+	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME);
+	if (!name) {
+		dev_err(&pdev->dev, "couldn't allocat name\n");
+		return -ENOMEM;
+	}
+
+	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, name, NULL,
+				      ddr_perf_offline_cpu);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
+		return ret;
+	}
+	pmu->cpuhp_state = ret;
+
+	/* Register the pmu instance for cpu hotplug */
+	ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
+	if (ret) {
+		dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
+		goto cpuhp_instance_err;
+	}
+
+	fill_event_attr(pmu);
+
+	ret = perf_pmu_register(&pmu->pmu, name, -1);
+	if (ret) {
+		dev_err(&pdev->dev, "perf pmu register failed\n");
+		goto pmu_register_err;
+	}
+
+	pmu->name = name;
+	pmu->dev = &pdev->dev;
+	pmu->pmu_enabled = false;
+
+	platform_set_drvdata(pdev, pmu);
+
+	return 0;
+
+pmu_register_err:
+	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
+cpuhp_instance_err:
+	cpuhp_remove_state(pmu->cpuhp_state);
+
+	return ret;
+}
+EXPORT_SYMBOL(meson_ddr_pmu_create);
+
+int meson_ddr_pmu_remove(struct platform_device *pdev)
+{
+	struct ddr_pmu *pmu = platform_get_drvdata(pdev);
+
+	perf_pmu_unregister(&pmu->pmu);
+	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
+	cpuhp_remove_state(pmu->cpuhp_state);
+
+	return 0;
+}
+EXPORT_SYMBOL(meson_ddr_pmu_remove);
diff --git a/drivers/perf/amlogic/meson_g12_ddr_pmu.c b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
new file mode 100644
index 000000000000..ba1908733bee
--- /dev/null
+++ b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
@@ -0,0 +1,388 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
+ */
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/types.h>
+#include <linux/version.h>
+
+#include <soc/amlogic/meson_ddr_pmu.h>
+
+#define PORT_MAJOR		32
+#define DEFAULT_XTAL_FREQ	24000000UL
+
+#define DMC_QOS_IRQ		BIT(30)
+
+/* DMC bandwidth monitor register address offset */
+#define DMC_MON_G12_CTRL0		(0x20  << 2)
+#define DMC_MON_G12_CTRL1		(0x21  << 2)
+#define DMC_MON_G12_CTRL2		(0x22  << 2)
+#define DMC_MON_G12_CTRL3		(0x23  << 2)
+#define DMC_MON_G12_CTRL4		(0x24  << 2)
+#define DMC_MON_G12_CTRL5		(0x25  << 2)
+#define DMC_MON_G12_CTRL6		(0x26  << 2)
+#define DMC_MON_G12_CTRL7		(0x27  << 2)
+#define DMC_MON_G12_CTRL8		(0x28  << 2)
+
+#define DMC_MON_G12_ALL_REQ_CNT		(0x29  << 2)
+#define DMC_MON_G12_ALL_GRANT_CNT	(0x2a  << 2)
+#define DMC_MON_G12_ONE_GRANT_CNT	(0x2b  << 2)
+#define DMC_MON_G12_SEC_GRANT_CNT	(0x2c  << 2)
+#define DMC_MON_G12_THD_GRANT_CNT	(0x2d  << 2)
+#define DMC_MON_G12_FOR_GRANT_CNT	(0x2e  << 2)
+#define DMC_MON_G12_TIMER		(0x2f  << 2)
+
+/* Each bit represent a axi line */
+PMU_FORMAT_ATTR(event, "config:0-7");
+PMU_FORMAT_ATTR(arm, "config1:0");
+PMU_FORMAT_ATTR(gpu, "config1:1");
+PMU_FORMAT_ATTR(pcie, "config1:2");
+PMU_FORMAT_ATTR(hdcp, "config1:3");
+PMU_FORMAT_ATTR(hevc_front, "config1:4");
+PMU_FORMAT_ATTR(usb3_0, "config1:6");
+PMU_FORMAT_ATTR(device, "config1:7");
+PMU_FORMAT_ATTR(hevc_back, "config1:8");
+PMU_FORMAT_ATTR(h265enc, "config1:9");
+PMU_FORMAT_ATTR(vpu_read1, "config1:16");
+PMU_FORMAT_ATTR(vpu_read2, "config1:17");
+PMU_FORMAT_ATTR(vpu_read3, "config1:18");
+PMU_FORMAT_ATTR(vpu_write1, "config1:19");
+PMU_FORMAT_ATTR(vpu_write2, "config1:20");
+PMU_FORMAT_ATTR(vdec, "config1:21");
+PMU_FORMAT_ATTR(hcodec, "config1:22");
+PMU_FORMAT_ATTR(ge2d, "config1:23");
+
+PMU_FORMAT_ATTR(spicc1, "config1:32");
+PMU_FORMAT_ATTR(usb0, "config1:33");
+PMU_FORMAT_ATTR(dma, "config1:34");
+PMU_FORMAT_ATTR(arb0, "config1:35");
+PMU_FORMAT_ATTR(sd_emmc_b, "config1:36");
+PMU_FORMAT_ATTR(usb1, "config1:37");
+PMU_FORMAT_ATTR(audio, "config1:38");
+PMU_FORMAT_ATTR(aififo, "config1:39");
+PMU_FORMAT_ATTR(parser, "config1:41");
+PMU_FORMAT_ATTR(ao_cpu, "config1:42");
+PMU_FORMAT_ATTR(sd_emmc_c, "config1:43");
+PMU_FORMAT_ATTR(spicc2, "config1:44");
+PMU_FORMAT_ATTR(ethernet, "config1:45");
+PMU_FORMAT_ATTR(sana, "config1:46");
+
+/* for sm1 and g12b */
+PMU_FORMAT_ATTR(nna, "config1:10");
+
+/* for g12b only */
+PMU_FORMAT_ATTR(gdc, "config1:11");
+PMU_FORMAT_ATTR(mipi_isp, "config1:12");
+PMU_FORMAT_ATTR(arm1, "config1:13");
+PMU_FORMAT_ATTR(sd_emmc_a, "config1:40");
+
+static struct attribute *g12_pmu_format_attrs[] = {
+	&format_attr_event.attr,
+	&format_attr_arm.attr,
+	&format_attr_gpu.attr,
+	&format_attr_nna.attr,
+	&format_attr_gdc.attr,
+	&format_attr_arm1.attr,
+	&format_attr_mipi_isp.attr,
+	&format_attr_sd_emmc_a.attr,
+	&format_attr_pcie.attr,
+	&format_attr_hdcp.attr,
+	&format_attr_hevc_front.attr,
+	&format_attr_usb3_0.attr,
+	&format_attr_device.attr,
+	&format_attr_hevc_back.attr,
+	&format_attr_h265enc.attr,
+	&format_attr_vpu_read1.attr,
+	&format_attr_vpu_read2.attr,
+	&format_attr_vpu_read3.attr,
+	&format_attr_vpu_write1.attr,
+	&format_attr_vpu_write2.attr,
+	&format_attr_vdec.attr,
+	&format_attr_hcodec.attr,
+	&format_attr_ge2d.attr,
+	&format_attr_spicc1.attr,
+	&format_attr_usb0.attr,
+	&format_attr_dma.attr,
+	&format_attr_arb0.attr,
+	&format_attr_sd_emmc_b.attr,
+	&format_attr_usb1.attr,
+	&format_attr_audio.attr,
+	&format_attr_aififo.attr,
+	&format_attr_parser.attr,
+	&format_attr_ao_cpu.attr,
+	&format_attr_sd_emmc_c.attr,
+	&format_attr_spicc2.attr,
+	&format_attr_ethernet.attr,
+	&format_attr_sana.attr,
+	NULL,
+};
+
+/* calculate ddr clock */
+static unsigned long dmc_g12_get_freq_quick(struct dmc_hw_info *info)
+{
+	unsigned int val;
+	unsigned int n, m, od1;
+	unsigned int od_div = 0xfff;
+	unsigned long freq = 0;
+
+	val = readl(info->pll_reg);
+	val = val & 0xfffff;
+	switch ((val >> 16) & 7) {
+	case 0:
+		od_div = 2;
+		break;
+
+	case 1:
+		od_div = 3;
+		break;
+
+	case 2:
+		od_div = 4;
+		break;
+
+	case 3:
+		od_div = 6;
+		break;
+
+	case 4:
+		od_div = 8;
+		break;
+
+	default:
+		break;
+	}
+
+	m = val & 0x1ff;
+	n = ((val >> 10) & 0x1f);
+	od1 = (((val >> 19) & 0x1)) == 1 ? 2 : 1;
+	freq = DEFAULT_XTAL_FREQ / 1000;        /* avoid overflow */
+	if (n)
+		freq = ((((freq * m) / n) >> od1) / od_div) * 1000;
+
+	return freq;
+}
+
+#ifdef DEBUG
+static void g12_dump_reg(struct dmc_hw_info *db)
+{
+	int s = 0, i;
+	unsigned int r;
+
+	for (i = 0; i < 9; i++) {
+		r  = readl(db->ddr_reg[0] + (DMC_MON_G12_CTRL0 + (i << 2)));
+		pr_notice("DMC_MON_CTRL%d:        %08x\n", i, r);
+	}
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_ALL_REQ_CNT);
+	pr_notice("DMC_MON_ALL_REQ_CNT:  %08x\n", r);
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_ALL_GRANT_CNT);
+	pr_notice("DMC_MON_ALL_GRANT_CNT:%08x\n", r);
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_ONE_GRANT_CNT);
+	pr_notice("DMC_MON_ONE_GRANT_CNT:%08x\n", r);
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_SEC_GRANT_CNT);
+	pr_notice("DMC_MON_SEC_GRANT_CNT:%08x\n", r);
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_THD_GRANT_CNT);
+	pr_notice("DMC_MON_THD_GRANT_CNT:%08x\n", r);
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_FOR_GRANT_CNT);
+	pr_notice("DMC_MON_FOR_GRANT_CNT:%08x\n", r);
+	r  = readl(db->ddr_reg[0] + DMC_MON_G12_TIMER);
+	pr_notice("DMC_MON_TIMER:        %08x\n", r);
+}
+#endif
+
+static void dmc_g12_counter_enable(struct dmc_hw_info *info)
+{
+	unsigned int val;
+	unsigned long clock_count = dmc_g12_get_freq_quick(info) / 10; /* 100ms */
+
+	writel(clock_count, info->ddr_reg[0] + DMC_MON_G12_TIMER);
+
+	val = readl(info->ddr_reg[0] + DMC_MON_G12_CTRL0);
+
+	/* enable all channel */
+	val =  BIT(31) |	/* enable bit */
+	       BIT(20) |	/* use timer  */
+	       0x0f;		/* 4 channels */
+
+	writel(val, info->ddr_reg[0] + DMC_MON_G12_CTRL0);
+
+#ifdef DEBUG
+	g12_dump_reg(info);
+#endif
+}
+
+static void dmc_g12_config_fiter(struct dmc_hw_info *info,
+				 int port, int channel)
+{
+	u32 val;
+	u32 rp[MAX_CHANNEL_NUM] = {DMC_MON_G12_CTRL1, DMC_MON_G12_CTRL3,
+					DMC_MON_G12_CTRL5, DMC_MON_G12_CTRL7};
+	u32 rs[MAX_CHANNEL_NUM] = {DMC_MON_G12_CTRL2, DMC_MON_G12_CTRL4,
+					DMC_MON_G12_CTRL6, DMC_MON_G12_CTRL8};
+	int subport = -1;
+
+	/* clear all port mask */
+	if (port < 0) {
+		writel(0, info->ddr_reg[0] + rp[channel]);
+		writel(0, info->ddr_reg[0] + rs[channel]);
+		return;
+	}
+
+	if (port >= PORT_MAJOR)
+		subport = port - PORT_MAJOR;
+
+	if (subport < 0) {
+		val = readl(info->ddr_reg[0] + rp[channel]);
+		val |=  (1 << port);
+		writel(val, info->ddr_reg[0] + rp[channel]);
+		val = 0xffff;
+		writel(val, info->ddr_reg[0] + rs[channel]);
+	} else {
+		val = BIT(23);		/* select device */
+		writel(val, info->ddr_reg[0] + rp[channel]);
+		val = readl(info->ddr_reg[0] + rs[channel]);
+		val |= (1 << subport);
+		writel(val, info->ddr_reg[0] + rs[channel]);
+	}
+}
+
+static void dmc_g12_config_axi_id(struct dmc_hw_info *info, int axi_id, int channel)
+{
+	if (channel > info->chann_nr)
+		return;
+
+	dmc_g12_config_fiter(info, axi_id, channel);
+}
+
+static void dmc_g12_counter_disable(struct dmc_hw_info *info)
+{
+	int i;
+
+	/* clear timer */
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_CTRL0);
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_TIMER);
+
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_ALL_REQ_CNT);
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_ALL_GRANT_CNT);
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_ONE_GRANT_CNT);
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_SEC_GRANT_CNT);
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_THD_GRANT_CNT);
+	writel(0, info->ddr_reg[0] + DMC_MON_G12_FOR_GRANT_CNT);
+
+	/* clear port channel mapping */
+	for (i = 0; i < info->chann_nr; i++)
+		dmc_g12_config_fiter(info, -1, i);
+}
+
+static void dmc_g12_get_counters(struct dmc_hw_info *info,
+				 struct dmc_counter *counter)
+{
+	int i;
+	unsigned int reg;
+
+	counter->all_cnt = readl(info->ddr_reg[0] + DMC_MON_G12_ALL_GRANT_CNT);
+	counter->all_req   = readl(info->ddr_reg[0] + DMC_MON_G12_ALL_REQ_CNT);
+
+	for (i = 0; i < info->chann_nr; i++) {
+		reg = DMC_MON_G12_ONE_GRANT_CNT + (i << 2);
+		counter->channel_cnt[i] = readl(info->ddr_reg[0] + reg);
+	}
+}
+
+static int dmc_g12_irq_handler(struct dmc_hw_info *info,
+			       struct dmc_counter *counter)
+{
+	unsigned int val;
+	int ret = -EINVAL;
+
+	val = readl(info->ddr_reg[0] + DMC_MON_G12_CTRL0);
+	if (val & DMC_QOS_IRQ) {
+		dmc_g12_get_counters(info, counter);
+		/* clear irq flags */
+		writel(val, info->ddr_reg[0] + DMC_MON_G12_CTRL0);
+		ret = 0;
+	}
+	return ret;
+}
+
+static struct dmc_pmu_hw_ops g12_ops = {
+	.enable		= dmc_g12_counter_enable,
+	.disable	= dmc_g12_counter_disable,
+	.irq_handler	= dmc_g12_irq_handler,
+	.get_counters	= dmc_g12_get_counters,
+	.config_axi_id	= dmc_g12_config_axi_id,
+};
+
+static int __init g12_ddr_pmu_probe(struct platform_device *pdev)
+{
+	struct ddr_pmu *pmu;
+
+	if (of_device_is_compatible(pdev->dev.of_node,
+				    "amlogic,g12a-ddr-pmu")) {
+		format_attr_nna.attr.mode = 0;
+		format_attr_gdc.attr.mode = 0;
+		format_attr_arm1.attr.mode = 0;
+		format_attr_mipi_isp.attr.mode = 0;
+	} else if (of_device_is_compatible(pdev->dev.of_node,
+					   "amlogic,sm1-ddr-pmu")) {
+		format_attr_gdc.attr.mode = 0;
+		format_attr_arm1.attr.mode = 0;
+		format_attr_mipi_isp.attr.mode = 0;
+	}
+
+	pmu = devm_kzalloc(&pdev->dev, sizeof(struct ddr_pmu), GFP_KERNEL);
+	if (!pmu)
+		return -ENOMEM;
+
+	/*
+	 * G12 series Soc have single dmc controller and
+	 * 4x ddr bandwidth monitor channels
+	 */
+	pmu->info.dmc_nr = 1;
+	pmu->info.chann_nr = 4;
+	pmu->info.ops = &g12_ops;
+	pmu->info.fmt_attr = g12_pmu_format_attrs;
+
+	return meson_ddr_pmu_create(pdev, pmu);
+}
+
+static int __exit g12_ddr_pmu_remove(struct platform_device *pdev)
+{
+	meson_ddr_pmu_remove(pdev);
+
+	return 0;
+}
+
+static const struct of_device_id meson_ddr_pmu_dt_match[] = {
+	{
+		.compatible = "amlogic,g12-ddr-pmu",
+	},
+	{
+		.compatible = "amlogic,g12a-ddr-pmu",
+	},
+	{
+		.compatible = "amlogic,g12b-ddr-pmu",
+	},
+	{
+		.compatible = "amlogic,sm1-ddr-pmu",
+	},
+	{}
+};
+
+static struct platform_driver g12_ddr_pmu_driver = {
+	.driver = {
+		.name = "amlogic,ddr-pmu",
+		.of_match_table = meson_ddr_pmu_dt_match,
+	},
+	.remove = __exit_p(g12_ddr_pmu_remove),
+};
+
+module_platform_driver_probe(g12_ddr_pmu_driver, g12_ddr_pmu_probe);
+MODULE_AUTHOR("Jiucheng Xu");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Amlogic G12 series SoC DDR PMU");
diff --git a/include/soc/amlogic/meson_ddr_pmu.h b/include/soc/amlogic/meson_ddr_pmu.h
new file mode 100644
index 000000000000..882efe3c2f58
--- /dev/null
+++ b/include/soc/amlogic/meson_ddr_pmu.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
+ */
+
+#ifndef __MESON_DDR_PMU_H__
+#define __MESON_DDR_PMU_H__
+
+#define MAX_CHANNEL_NUM		8
+
+enum {
+	ALL_CHAN_COUNTER_ID,
+	CHAN1_COUNTER_ID,
+	CHAN2_COUNTER_ID,
+	CHAN3_COUNTER_ID,
+	CHAN4_COUNTER_ID,
+	CHAN5_COUNTER_ID,
+	CHAN6_COUNTER_ID,
+	CHAN7_COUNTER_ID,
+	CHAN8_COUNTER_ID,
+	COUNTER_MAX_ID,
+};
+
+struct dmc_hw_info;
+
+struct dmc_counter {
+	u64 all_cnt;	/* The count of all requests come in/out ddr controller */
+	union {
+		u64 all_req;
+		struct {
+			u64 all_idle_cnt;
+			u64 all_16bit_cnt;
+		};
+	};
+	u64 channel_cnt[MAX_CHANNEL_NUM]; /* To save a DMC bandwidth-monitor channel counter */
+};
+
+struct dmc_pmu_hw_ops {
+	void (*enable)(struct dmc_hw_info *info);
+	void (*disable)(struct dmc_hw_info *info);
+	/* Bind an axi line to a bandwidth-monitor channel */
+	void (*config_axi_id)(struct dmc_hw_info *info, int axi_id, int chann);
+	int (*irq_handler)(struct dmc_hw_info *info,
+			   struct dmc_counter *counter);
+	void (*get_counters)(struct dmc_hw_info *info,
+			     struct dmc_counter *counter);
+};
+
+struct dmc_hw_info {
+	struct dmc_pmu_hw_ops *ops;
+	void __iomem *ddr_reg[4];
+	unsigned long timer_value;	/* Timer value in TIMER register */
+	void __iomem *pll_reg;
+	int irq_num;			/* irq vector number */
+	int dmc_nr;			/* The number of dmc controller */
+	int chann_nr;			/* The number of dmc bandwidth monitor channels */
+	int id;				/* The number of supported channels */
+	struct attribute **fmt_attr;
+};
+
+struct ddr_pmu {
+	struct pmu pmu;
+	struct dmc_hw_info info;
+	struct dmc_counter counters;	/* save counters from hw */
+	bool pmu_enabled;
+	struct device *dev;
+	char *name;
+	struct hlist_node node;
+	enum cpuhp_state cpuhp_state;
+	int cpu;			/* for cpu hotplug */
+};
+
+int meson_ddr_pmu_create(struct platform_device *pdev, struct ddr_pmu *pmu);
+int meson_ddr_pmu_remove(struct platform_device *pdev);
+
+#endif /* __MESON_DDR_PMU_H__ */
-- 
2.25.1

[PATCH v4 2/4] docs/perf: Add documentation for the Amlogic G12 DDR PMU

[Jiucheng Xu]

Add a user guide to show how to use DDR PMU to
monitor DDR bandwidth on Amlogic G12 SoC

Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
---
Changes v3 -> v4:
  - No change

Changes v2 -> v3:
  - Rename doc name from aml-ddr-pmu.rst to meson-ddr-pmu.rst

Changes v1 -> v2:
  - Nothing was changed
---
 .../admin-guide/perf/meson-ddr-pmu.rst        | 68 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 69 insertions(+)
 create mode 100644 Documentation/admin-guide/perf/meson-ddr-pmu.rst

diff --git a/Documentation/admin-guide/perf/meson-ddr-pmu.rst b/Documentation/admin-guide/perf/meson-ddr-pmu.rst
new file mode 100644
index 000000000000..f8601f3b103e
--- /dev/null
+++ b/Documentation/admin-guide/perf/meson-ddr-pmu.rst
@@ -0,0 +1,68 @@
+.. SPDX-License-Identifier: GPL-2.0
+===========================================================
+Amlogic SoC DDR Bandwidth Performance Monitoring Unit (PMU)
+===========================================================
+
+There is a bandwidth monitor inside the DRAM contorller. The monitor include
+4 channels which can count the read/write request of accessing DRAM individually.
+It can be helpful to show if the performance bottleneck is on DDR bandwidth.
+
+Currently, this driver supports the following 5 Perf events:
+
+aml_ddr_bw/total_rw_bytes/
+aml_ddr_bw/chan_1_rw_bytes/
+aml_ddr_bw/chan_2_rw_bytes/
+aml_ddr_bw/chan_3_rw_bytes/
+aml_ddr_bw/chan_4_rw_bytes/
+
+aml_ddr_bw/chan_{1,2,3,4}_rw_bytes/ events are the channel related events.
+Each channel support using keywords as filter, which can let the channel
+to monitor the individual IP module in SoC.
+
+The following keywords are the filter:
+
+arm             - DDR access request from CPU
+vpu_read1       - DDR access request from OSD + VPP read
+gpu             - DDR access request from 3D GPU
+pcie            - DDR access request from PCIe controller
+hdcp            - DDR access request from HDCP controller
+hevc_front      - DDR access request from HEVC codec front end
+usb3_0          - DDR access request from USB3.0 controller
+hevc_back       - DDR access request from HEVC codec back end
+h265enc         - DDR access request from HEVC encoder
+vpu_read2       - DDR access request from DI read
+vpu_write1      - DDR access request from VDIN write
+vpu_write2      - DDR access request from di write
+vdec            - DDR access request from legacy codec video decoder
+hcodec          - DDR access request from H264 encoder
+ge2d            - DDR access request from ge2d
+spicc1          - DDR access request from SPI controller 1
+usb0            - DDR access request from USB2.0 controller 0
+dma             - DDR access request from system DMA controller 1
+arb0            - DDR access request from arb0
+sd_emmc_b       - DDR access request from SD eMMC b controller
+usb1            - DDR access request from USB2.0 controller 1
+audio           - DDR access request from Audio module
+sd_emmc_c       - DDR access request from SD eMMC c controller
+spicc2          - DDR access request from SPI controller 2
+ethernet        - DDR access request from Ethernet controller
+
+The following command is to show the total DDR bandwidth:
+
+    .. code-block::bash
+
+        perf stat -a -e aml_ddr_bw/total_rw_bytes/ -I 1000 sleep 10
+
+This command will print the total DDR bandwidth per second.
+
+The following commands are to show how to use filter parameters:
+
+    .. code-block::bash
+
+        perf stat -a -e aml_ddr_bw/chan_1_rw_bytes,arm=1/ -I 1000 sleep 10
+        perf stat -a -e aml_ddr_bw/chan_2_rw_bytes,gpu=1/ -I 1000 sleep 10
+        perf stat -a -e aml_ddr_bw/chan_3_rw_bytes,arm=1,gpu=1/ -I 1000 sleep 10
+
+The 1st command show how to use channel 1 to monitor the DDR bandwidth from ARM.
+The 2nd command show using channel 2 to get the DDR bandwidth of GPU.
+The 3rd command show using channel 3 to monitor the sum of ARM and GPU.
diff --git a/MAINTAINERS b/MAINTAINERS
index ac8a98dfbacc..8ee68e699e6d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1054,6 +1054,7 @@ AMLOGIC DDR PMU DRIVER
 M:	Jiucheng Xu <jiucheng.xu@amlogic.com>
 S:	Supported
 W:	http://www.amlogic.com
+F:	Documentation/admin-guide/perf/meson-ddr-pmu.rst
 F:	drivers/perf/amlogic/
 F:	include/soc/amlogic/
 
-- 
2.25.1

[PATCH v4 3/4] arm64: dts: meson: Add DDR PMU node

[Jiucheng Xu]

Add DDR PMU device node for G12 series SoC

Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
---
Changes v3 -> v4:
  - No change

Changes v2 -> v3:
  - No change

Changes v1 -> v2:
  - Remove model, dmc_nr, chann_nr properties
  - Add g12a-ddr-pmu, g12b-ddr-pmu, sm1-ddr-pmu compatibles as
    identifier
---
 arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 7 +++++++
 arch/arm64/boot/dts/amlogic/meson-g12a.dtsi       | 4 ++++
 arch/arm64/boot/dts/amlogic/meson-g12b.dtsi       | 4 ++++
 arch/arm64/boot/dts/amlogic/meson-sm1.dtsi        | 4 ++++
 4 files changed, 19 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
index 45947c1031c4..7e556fe575be 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
@@ -2146,6 +2146,13 @@ hdmi_tx_out: endpoint {
 			};
 		};
 
+		ddr_pmu: ddr_pmu@ff638000 {
+			compatible = "amlogic,g12-ddr-pmu";
+			reg = <0x0 0xff638000 0x0 0x100
+			       0x0 0xff638c00 0x0 0x100>;
+			interrupts = <GIC_SPI 52 IRQ_TYPE_EDGE_RISING>;
+		};
+
 		gic: interrupt-controller@ffc01000 {
 			compatible = "arm,gic-400";
 			reg = <0x0 0xffc01000 0 0x1000>,
diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
index fb0ab27d1f64..4a32e081e70e 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
@@ -133,3 +133,7 @@ map1 {
 		};
 	};
 };
+
+&ddr_pmu {
+	compatible = "amlogic,g12a-ddr-pmu";
+};
diff --git a/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi
index ee8fcae9f9f0..d91eca5a9afc 100644
--- a/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-g12b.dtsi
@@ -139,3 +139,7 @@ map1 {
 &mali {
 	dma-coherent;
 };
+
+&ddr_pmu {
+	compatible = "amlogic,g12b-ddr-pmu";
+};
diff --git a/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi b/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi
index 80737731af3f..7d62c661fde5 100644
--- a/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi
@@ -543,3 +543,7 @@ &vpu {
 &usb {
 	power-domains = <&pwrc PWRC_SM1_USB_ID>;
 };
+
+&ddr_pmu {
+	compatible = "amlogic,sm1-ddr-pmu";
+};
-- 
2.25.1

[PATCH v4 4/4] dt-binding: perf: Add Amlogic DDR PMU

[Jiucheng Xu]

Add binding documentation for the Amlogic G12 series DDR
performance monitor unit.

Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
---
Changes v3 -> v4:
  - Fix "$id: relative path/filename doesn't match actual path or
    filename" warning

Changes v2 -> v3:
  - Remove oneOf
  - Add descriptions
  - Fix compiling warning

Changes v1 -> v2:
  - Rename file, from aml_ddr_pmu.yaml to amlogic,g12_ddr_pmu.yaml
  - Delete "model", "dmc_nr", "chann_nr" new properties
  - Fix compiling error
---
 .../bindings/perf/amlogic,g12-ddr-pmu.yaml    | 52 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 53 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml

diff --git a/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
new file mode 100644
index 000000000000..4d018574ffd1
--- /dev/null
+++ b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
@@ -0,0 +1,52 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/perf/amlogic,g12-ddr-pmu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Amlogic G12 DDR performance monitor
+
+maintainers:
+  - Jiucheng Xu <jiucheng.xu@amlogic.com>
+
+description: |
+  Amlogic G12 series SoC integrate DDR bandwidth monitor.
+  A timer is inside and can generate interrupt when timeout.
+  The bandwidth is counted in the timer ISR. Different platform
+  has different subset of event format attribute.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - amlogic,g12b-ddr-pmu
+          - amlogic,g12a-ddr-pmu
+          - amlogic,sm1-ddr-pmu
+
+  reg:
+    items:
+      - description: Physical address of DMC bandwidth register
+          and size of the configuration address space.
+      - description: Physical address of DMC PLL register and
+          size of the configuration address space.
+
+  interrupts:
+    items:
+      - description: The IRQ of the inside timer timeout.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    ddr_pmu@ff638000 {
+        compatible = "amlogic,g12a-ddr-pmu";
+        reg = <0xff638000 0x100
+               0xff638c00 0x100>;
+        interrupts = <GIC_SPI 52 IRQ_TYPE_EDGE_RISING>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 8ee68e699e6d..67c2c9e8c4ea 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1055,6 +1055,7 @@ M:	Jiucheng Xu <jiucheng.xu@amlogic.com>
 S:	Supported
 W:	http://www.amlogic.com
 F:	Documentation/admin-guide/perf/meson-ddr-pmu.rst
+F:	Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
 F:	drivers/perf/amlogic/
 F:	include/soc/amlogic/
 
-- 
2.25.1

Re: [PATCH v4 4/4] dt-binding: perf: Add Amlogic DDR PMU

[Krzysztof Kozlowski]

On 05/08/2022 09:14, Jiucheng Xu wrote:
> Add binding documentation for the Amlogic G12 series DDR
> performance monitor unit.
> 

Bindings go first in the series, before their implementation.

> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
> ---
> Changes v3 -> v4:
>   - Fix "$id: relative path/filename doesn't match actual path or
>     filename" warning
> 
> Changes v2 -> v3:
>   - Remove oneOf
>   - Add descriptions
>   - Fix compiling warning
> 
> Changes v1 -> v2:
>   - Rename file, from aml_ddr_pmu.yaml to amlogic,g12_ddr_pmu.yaml
>   - Delete "model", "dmc_nr", "chann_nr" new properties
>   - Fix compiling error
> ---
>  .../bindings/perf/amlogic,g12-ddr-pmu.yaml    | 52 +++++++++++++++++++
>  MAINTAINERS                                   |  1 +
>  2 files changed, 53 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
> 
> diff --git a/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
> new file mode 100644
> index 000000000000..4d018574ffd1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
> @@ -0,0 +1,52 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/perf/amlogic,g12-ddr-pmu.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Amlogic G12 DDR performance monitor
> +
> +maintainers:
> +  - Jiucheng Xu <jiucheng.xu@amlogic.com>
> +
> +description: |
> +  Amlogic G12 series SoC integrate DDR bandwidth monitor.
> +  A timer is inside and can generate interrupt when timeout.
> +  The bandwidth is counted in the timer ISR. Different platform
> +  has different subset of event format attribute.
> +
> +properties:
> +  compatible:
> +    items:

You have only one item, so remove "items".

> +      - enum:
> +          - amlogic,g12b-ddr-pmu
> +          - amlogic,g12a-ddr-pmu
> +          - amlogic,sm1-ddr-pmu
> +
> +  reg:
> +    items:
> +      - description: Physical address of DMC bandwidth register
> +          and size of the configuration address space.

Skip obvious pieces, so only:

description: DMC bandwidth register space

> +      - description: Physical address of DMC PLL register and
> +          size of the configuration address space.

description: DMC PLL bandwidth register space


> +
> +  interrupts:
> +    items:
> +      - description: The IRQ of the inside timer timeout.
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    ddr_pmu@ff638000 {

No underscores in node names, generic node names, so just "pmu".
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> +        compatible = "amlogic,g12a-ddr-pmu";
> +        reg = <0xff638000 0x100
> +               0xff638c00 0x100>;

This is still not fixed. Binding says you have two items, but you
declared here only one item.

Best regards,
Krzysztof

Re: [PATCH v4 3/4] arm64: dts: meson: Add DDR PMU node

[Krzysztof Kozlowski]

On 05/08/2022 09:14, Jiucheng Xu wrote:
> Add DDR PMU device node for G12 series SoC
> 
> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
> ---
> Changes v3 -> v4:
>   - No change
> 
> Changes v2 -> v3:
>   - No change
> 
> Changes v1 -> v2:
>   - Remove model, dmc_nr, chann_nr properties
>   - Add g12a-ddr-pmu, g12b-ddr-pmu, sm1-ddr-pmu compatibles as
>     identifier
> ---
>  arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 7 +++++++
>  arch/arm64/boot/dts/amlogic/meson-g12a.dtsi       | 4 ++++
>  arch/arm64/boot/dts/amlogic/meson-g12b.dtsi       | 4 ++++
>  arch/arm64/boot/dts/amlogic/meson-sm1.dtsi        | 4 ++++
>  4 files changed, 19 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> index 45947c1031c4..7e556fe575be 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
> @@ -2146,6 +2146,13 @@ hdmi_tx_out: endpoint {
>  			};
>  		};
>  
> +		ddr_pmu: ddr_pmu@ff638000 {

No underscores in node names.

Node names should be generic, so pmu.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> +			compatible = "amlogic,g12-ddr-pmu";
> +			reg = <0x0 0xff638000 0x0 0x100
> +			       0x0 0xff638c00 0x0 0x100>;
> +			interrupts = <GIC_SPI 52 IRQ_TYPE_EDGE_RISING>;
> +		};
> +
>  		gic: interrupt-controller@ffc01000 {
>  			compatible = "arm,gic-400";
>  			reg = <0x0 0xffc01000 0 0x1000>,
> diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
> index fb0ab27d1f64..4a32e081e70e 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
> @@ -133,3 +133,7 @@ map1 {
>  		};
>  	};
>  };
> +
> +&ddr_pmu {
> +	compatible = "amlogic,g12a-ddr-pmu";
> +};

Adding nodes at the end causes conflicts. They should be added in some
order...

Best regards,
Krzysztof

Re: [PATCH v4 1/4] perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

[Krzysztof Kozlowski]

On 05/08/2022 09:14, Jiucheng Xu wrote:
> This patch adds support Amlogic meson G12 series SoC
> DDR bandwidth PMU driver framework and interfaces.
> 
> The PMU not only can monitor the total DDR bandwidth,
> but also the bandwidth which is from individual IP module.
> 
> Example usage:
> 
>  $ perf stat -a -e aml_ddr_bw/total_rw_bytes/ -I 1000 sleep 10
> 
> - or -

Thank you for your patch. There is something to discuss/improve.

> +
> +static void fmt_attr_fill(struct attribute **fmt_attr)
> +{
> +	int i;
> +
> +	for (i = 0; fmt_attr[i]; i++)
> +		ddr_perf_format_attrs[i] = fmt_attr[i];
> +
> +	ddr_perf_format_attrs[i] = NULL;
> +}
> +
> +static int ddr_pmu_parse_dt(struct platform_device *pdev, struct dmc_hw_info *info)
> +{
> +	/*struct pinctrl *p;*/

No dead code in kernel.

> +	void __iomem *base;
> +	int i, ret = -EINVAL;
> +
> +	for (i = 0; i < info->dmc_nr; i++) {

Your binding does not allow to have more than 1. Remove dead code.

> +		/* resource 0 for ddr register base */
> +		base = devm_platform_ioremap_resource(pdev, i);
> +		if (IS_ERR(base)) {
> +			dev_err(&pdev->dev, "couldn't ioremap ddr reg %d\n", i);

Error message is not needed.

> +			return PTR_ERR(base);
> +		}
> +		info->ddr_reg[i] = base;
> +	}
> +
> +	/* resource i for pll register base */
> +	base = devm_platform_ioremap_resource(pdev, i);
> +	if (IS_ERR(base)) {
> +		dev_err(&pdev->dev, "couldn't ioremap for pll reg\n");

Error message is not needed.

> +		return PTR_ERR(base);
> +	}
> +	info->pll_reg = base;
> +
> +	ret = platform_get_irq(pdev, 0);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "couldn't get irq\n");

Error message is not needed.

> +		return ret;
> +	}
> +	info->irq_num = ret;
> +
> +	ret = devm_request_irq(&pdev->dev, info->irq_num, dmc_irq_handler,
> +			       IRQF_NOBALANCING, dev_name(&pdev->dev),
> +			       (void *)info);
> +	if (ret < 0)
> +		dev_err(&pdev->dev, "ddr request irq failed\n");
> +
> +	return ret;
> +}
> +
> +int meson_ddr_pmu_create(struct platform_device *pdev, struct ddr_pmu *pmu)
> +{
> +	int ret;
> +	char *name;
> +	struct pmu tmp_pmu = {
> +		.module		= THIS_MODULE,
> +		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
> +		.task_ctx_nr	= perf_invalid_context,
> +		.attr_groups	= attr_groups,
> +		.event_init	= meson_ddr_perf_event_init,
> +		.add		= meson_ddr_perf_event_add,
> +		.del		= meson_ddr_perf_event_del,
> +		.start		= meson_ddr_perf_event_start,
> +		.stop		= meson_ddr_perf_event_stop,
> +		.read		= meson_ddr_perf_event_update,
> +	};
> +
> +	pmu->pmu = tmp_pmu;
> +
> +	ret = ddr_pmu_parse_dt(pdev, &pmu->info);
> +	if (ret < 0)
> +		return ret;
> +
> +	fmt_attr_fill(pmu->info.fmt_attr);
> +
> +	pmu->cpu = raw_smp_processor_id();

smp_processor_id()
(or why do you need to use raw?)


> +
> +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME);
> +	if (!name) {
> +		dev_err(&pdev->dev, "couldn't allocat name\n");

No error messages for allocation. Run basic tools on your code -
coccinelle, checkaptch, smatch and sparse.

> +		return -ENOMEM;
> +	}
> +
> +	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, name, NULL,
> +				      ddr_perf_offline_cpu);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
> +		return ret;
> +	}
> +	pmu->cpuhp_state = ret;
> +
> +	/* Register the pmu instance for cpu hotplug */
> +	ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
> +		goto cpuhp_instance_err;
> +	}
> +
> +	fill_event_attr(pmu);
> +
> +	ret = perf_pmu_register(&pmu->pmu, name, -1);
> +	if (ret) {
> +		dev_err(&pdev->dev, "perf pmu register failed\n");
> +		goto pmu_register_err;
> +	}
> +
> +	pmu->name = name;
> +	pmu->dev = &pdev->dev;
> +	pmu->pmu_enabled = false;
> +
> +	platform_set_drvdata(pdev, pmu);
> +
> +	return 0;
> +
> +pmu_register_err:
> +	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
> +cpuhp_instance_err:
> +	cpuhp_remove_state(pmu->cpuhp_state);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(meson_ddr_pmu_create);

Why is this exported?

Also misses kerneldoc.

> +
> +int meson_ddr_pmu_remove(struct platform_device *pdev)
> +{
> +	struct ddr_pmu *pmu = platform_get_drvdata(pdev);
> +
> +	perf_pmu_unregister(&pmu->pmu);
> +	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
> +	cpuhp_remove_state(pmu->cpuhp_state);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(meson_ddr_pmu_remove);

Why is this exported?

Also misses kerneldoc.

> diff --git a/drivers/perf/amlogic/meson_g12_ddr_pmu.c b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
> new file mode 100644
> index 000000000000..ba1908733bee
> --- /dev/null
> +++ b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
> @@ -0,0 +1,388 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
> + */

(...)

> +static int dmc_g12_irq_handler(struct dmc_hw_info *info,
> +			       struct dmc_counter *counter)
> +{
> +	unsigned int val;
> +	int ret = -EINVAL;
> +
> +	val = readl(info->ddr_reg[0] + DMC_MON_G12_CTRL0);
> +	if (val & DMC_QOS_IRQ) {
> +		dmc_g12_get_counters(info, counter);
> +		/* clear irq flags */
> +		writel(val, info->ddr_reg[0] + DMC_MON_G12_CTRL0);
> +		ret = 0;
> +	}
> +	return ret;
> +}
> +
> +static struct dmc_pmu_hw_ops g12_ops = {

static const?

> +	.enable		= dmc_g12_counter_enable,
> +	.disable	= dmc_g12_counter_disable,
> +	.irq_handler	= dmc_g12_irq_handler,
> +	.get_counters	= dmc_g12_get_counters,
> +	.config_axi_id	= dmc_g12_config_axi_id,
> +};
> +
> +static int __init g12_ddr_pmu_probe(struct platform_device *pdev)
> +{
> +	struct ddr_pmu *pmu;
> +
> +	if (of_device_is_compatible(pdev->dev.of_node,
> +				    "amlogic,g12a-ddr-pmu")) {
> +		format_attr_nna.attr.mode = 0;
> +		format_attr_gdc.attr.mode = 0;
> +		format_attr_arm1.attr.mode = 0;
> +		format_attr_mipi_isp.attr.mode = 0;

No. That's not correct patter. You must use variant specific driver data.

> +	} else if (of_device_is_compatible(pdev->dev.of_node,
> +					   "amlogic,sm1-ddr-pmu")) {
> +		format_attr_gdc.attr.mode = 0;
> +		format_attr_arm1.attr.mode = 0;
> +		format_attr_mipi_isp.attr.mode = 0;

No. That's not correct patter. You must use variant specific driver data.

> +	}
> +
> +	pmu = devm_kzalloc(&pdev->dev, sizeof(struct ddr_pmu), GFP_KERNEL);
> +	if (!pmu)
> +		return -ENOMEM;
> +
> +	/*
> +	 * G12 series Soc have single dmc controller and
> +	 * 4x ddr bandwidth monitor channels
> +	 */
> +	pmu->info.dmc_nr = 1;
> +	pmu->info.chann_nr = 4;
> +	pmu->info.ops = &g12_ops;
> +	pmu->info.fmt_attr = g12_pmu_format_attrs;
> +
> +	return meson_ddr_pmu_create(pdev, pmu);
> +}
> +
> +static int __exit g12_ddr_pmu_remove(struct platform_device *pdev)
> +{
> +	meson_ddr_pmu_remove(pdev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id meson_ddr_pmu_dt_match[] = {
> +	{
> +		.compatible = "amlogic,g12-ddr-pmu",

Undocumented compatible. Did you run checkpatch and fix all the errors?

> +	},
> +	{
> +		.compatible = "amlogic,g12a-ddr-pmu",
> +	},
> +	{
> +		.compatible = "amlogic,g12b-ddr-pmu",
> +	},
> +	{
> +		.compatible = "amlogic,sm1-ddr-pmu",

Why four different entries for the same devices without driver data?
This is confusing.

> +	},
> +	{}
> +};
> +
> +static struct platform_driver g12_ddr_pmu_driver = {
> +	.driver = {
> +		.name = "amlogic,ddr-pmu",
> +		.of_match_table = meson_ddr_pmu_dt_match,
> +	},
> +	.remove = __exit_p(g12_ddr_pmu_remove),

You made the driver non-hotpluggable - why?
In the same time it is still unbindable, whis is a bit confusing. If you
can unbind it, you should be able to hot-unplug it.

> +};
> +
> +module_platform_driver_probe(g12_ddr_pmu_driver, g12_ddr_pmu_probe);
> +MODULE_AUTHOR("Jiucheng Xu");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Amlogic G12 series SoC DDR PMU");
> diff --git a/include/soc/amlogic/meson_ddr_pmu.h b/include/soc/amlogic/meson_ddr_pmu.h
> new file mode 100644
> index 000000000000..882efe3c2f58
> --- /dev/null
> +++ b/include/soc/amlogic/meson_ddr_pmu.h
> @@ -0,0 +1,76 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
> + */
> +
> +#ifndef __MESON_DDR_PMU_H__
> +#define __MESON_DDR_PMU_H__
> +
> +#define MAX_CHANNEL_NUM		8
> +
> +enum {
> +	ALL_CHAN_COUNTER_ID,
> +	CHAN1_COUNTER_ID,
> +	CHAN2_COUNTER_ID,
> +	CHAN3_COUNTER_ID,
> +	CHAN4_COUNTER_ID,
> +	CHAN5_COUNTER_ID,
> +	CHAN6_COUNTER_ID,
> +	CHAN7_COUNTER_ID,
> +	CHAN8_COUNTER_ID,
> +	COUNTER_MAX_ID,
> +};
> +
> +struct dmc_hw_info;
> +
> +struct dmc_counter {
> +	u64 all_cnt;	/* The count of all requests come in/out ddr controller */
> +	union {
> +		u64 all_req;
> +		struct {
> +			u64 all_idle_cnt;
> +			u64 all_16bit_cnt;
> +		};
> +	};
> +	u64 channel_cnt[MAX_CHANNEL_NUM]; /* To save a DMC bandwidth-monitor channel counter */
> +};
> +
> +struct dmc_pmu_hw_ops {
> +	void (*enable)(struct dmc_hw_info *info);
> +	void (*disable)(struct dmc_hw_info *info);
> +	/* Bind an axi line to a bandwidth-monitor channel */
> +	void (*config_axi_id)(struct dmc_hw_info *info, int axi_id, int chann);
> +	int (*irq_handler)(struct dmc_hw_info *info,
> +			   struct dmc_counter *counter);
> +	void (*get_counters)(struct dmc_hw_info *info,
> +			     struct dmc_counter *counter);
> +};
> +
> +struct dmc_hw_info {
> +	struct dmc_pmu_hw_ops *ops;
> +	void __iomem *ddr_reg[4];
> +	unsigned long timer_value;	/* Timer value in TIMER register */
> +	void __iomem *pll_reg;
> +	int irq_num;			/* irq vector number */
> +	int dmc_nr;			/* The number of dmc controller */
> +	int chann_nr;			/* The number of dmc bandwidth monitor channels */
> +	int id;				/* The number of supported channels */
> +	struct attribute **fmt_attr;
> +};
> +
> +struct ddr_pmu {
> +	struct pmu pmu;
> +	struct dmc_hw_info info;
> +	struct dmc_counter counters;	/* save counters from hw */
> +	bool pmu_enabled;
> +	struct device *dev;
> +	char *name;
> +	struct hlist_node node;
> +	enum cpuhp_state cpuhp_state;
> +	int cpu;			/* for cpu hotplug */
> +};

Linux-wide headers should not include your private data structures.
Entier header looks unused - should be made private.

Best regards,
Krzysztof

Re: [PATCH v4 1/4] perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

[Jiucheng Xu]

On 2022/8/5 16:38, Krzysztof Kozlowski wrote:
> [ EXTERNAL EMAIL ]
>
> On 05/08/2022 09:14, Jiucheng Xu wrote:
>> This patch adds support Amlogic meson G12 series SoC
>> DDR bandwidth PMU driver framework and interfaces.
>>
>> The PMU not only can monitor the total DDR bandwidth,
>> but also the bandwidth which is from individual IP module.
>>
>> Example usage:
>>
>>   $ perf stat -a -e aml_ddr_bw/total_rw_bytes/ -I 1000 sleep 10
>>
>> - or -
> Thank you for your patch. There is something to discuss/improve.
>
>> +
>> +static void fmt_attr_fill(struct attribute **fmt_attr)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; fmt_attr[i]; i++)
>> +		ddr_perf_format_attrs[i] = fmt_attr[i];
>> +
>> +	ddr_perf_format_attrs[i] = NULL;
>> +}
>> +
>> +static int ddr_pmu_parse_dt(struct platform_device *pdev, struct dmc_hw_info *info)
>> +{
>> +	/*struct pinctrl *p;*/
> No dead code in kernel.
>
>> +	void __iomem *base;
>> +	int i, ret = -EINVAL;
>> +
>> +	for (i = 0; i < info->dmc_nr; i++) {
> Your binding does not allow to have more than 1. Remove dead code.
>
>> +		/* resource 0 for ddr register base */
>> +		base = devm_platform_ioremap_resource(pdev, i);
>> +		if (IS_ERR(base)) {
>> +			dev_err(&pdev->dev, "couldn't ioremap ddr reg %d\n", i);
> Error message is not needed.
>
>> +			return PTR_ERR(base);
>> +		}
>> +		info->ddr_reg[i] = base;
>> +	}
>> +
>> +	/* resource i for pll register base */
>> +	base = devm_platform_ioremap_resource(pdev, i);
>> +	if (IS_ERR(base)) {
>> +		dev_err(&pdev->dev, "couldn't ioremap for pll reg\n");
> Error message is not needed.
>
>> +		return PTR_ERR(base);
>> +	}
>> +	info->pll_reg = base;
>> +
>> +	ret = platform_get_irq(pdev, 0);
>> +	if (ret < 0) {
>> +		dev_err(&pdev->dev, "couldn't get irq\n");
> Error message is not needed.
>
>> +		return ret;
>> +	}
>> +	info->irq_num = ret;
>> +
>> +	ret = devm_request_irq(&pdev->dev, info->irq_num, dmc_irq_handler,
>> +			       IRQF_NOBALANCING, dev_name(&pdev->dev),
>> +			       (void *)info);
>> +	if (ret < 0)
>> +		dev_err(&pdev->dev, "ddr request irq failed\n");
>> +
>> +	return ret;
>> +}
>> +
>> +int meson_ddr_pmu_create(struct platform_device *pdev, struct ddr_pmu *pmu)
>> +{
>> +	int ret;
>> +	char *name;
>> +	struct pmu tmp_pmu = {
>> +		.module		= THIS_MODULE,
>> +		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
>> +		.task_ctx_nr	= perf_invalid_context,
>> +		.attr_groups	= attr_groups,
>> +		.event_init	= meson_ddr_perf_event_init,
>> +		.add		= meson_ddr_perf_event_add,
>> +		.del		= meson_ddr_perf_event_del,
>> +		.start		= meson_ddr_perf_event_start,
>> +		.stop		= meson_ddr_perf_event_stop,
>> +		.read		= meson_ddr_perf_event_update,
>> +	};
>> +
>> +	pmu->pmu = tmp_pmu;
>> +
>> +	ret = ddr_pmu_parse_dt(pdev, &pmu->info);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	fmt_attr_fill(pmu->info.fmt_attr);
>> +
>> +	pmu->cpu = raw_smp_processor_id();
> smp_processor_id()
> (or why do you need to use raw?)
>
>
>> +
>> +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME);
>> +	if (!name) {
>> +		dev_err(&pdev->dev, "couldn't allocat name\n");
> No error messages for allocation. Run basic tools on your code -
> coccinelle, checkaptch, smatch and sparse.
Okay, I just only run checkpatch. I will use the other tools to check my 
patches.
>
>> +		return -ENOMEM;
>> +	}
>> +
>> +	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, name, NULL,
>> +				      ddr_perf_offline_cpu);
>> +	if (ret < 0) {
>> +		dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
>> +		return ret;
>> +	}
>> +	pmu->cpuhp_state = ret;
>> +
>> +	/* Register the pmu instance for cpu hotplug */
>> +	ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
>> +		goto cpuhp_instance_err;
>> +	}
>> +
>> +	fill_event_attr(pmu);
>> +
>> +	ret = perf_pmu_register(&pmu->pmu, name, -1);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "perf pmu register failed\n");
>> +		goto pmu_register_err;
>> +	}
>> +
>> +	pmu->name = name;
>> +	pmu->dev = &pdev->dev;
>> +	pmu->pmu_enabled = false;
>> +
>> +	platform_set_drvdata(pdev, pmu);
>> +
>> +	return 0;
>> +
>> +pmu_register_err:
>> +	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
>> +cpuhp_instance_err:
>> +	cpuhp_remove_state(pmu->cpuhp_state);
>> +
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL(meson_ddr_pmu_create);
> Why is this exported?
>
> Also misses kerneldoc.
Okay, I will remove them.
>
>> +
>> +int meson_ddr_pmu_remove(struct platform_device *pdev)
>> +{
>> +	struct ddr_pmu *pmu = platform_get_drvdata(pdev);
>> +
>> +	perf_pmu_unregister(&pmu->pmu);
>> +	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
>> +	cpuhp_remove_state(pmu->cpuhp_state);
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL(meson_ddr_pmu_remove);
> Why is this exported?
>
> Also misses kerneldoc.
>
>> diff --git a/drivers/perf/amlogic/meson_g12_ddr_pmu.c b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
>> new file mode 100644
>> index 000000000000..ba1908733bee
>> --- /dev/null
>> +++ b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
>> @@ -0,0 +1,388 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
>> + */
> (...)
Do you mean a new blank line need be added?
>
>> +static int dmc_g12_irq_handler(struct dmc_hw_info *info,
>> +			       struct dmc_counter *counter)
>> +{
>> +	unsigned int val;
>> +	int ret = -EINVAL;
>> +
>> +	val = readl(info->ddr_reg[0] + DMC_MON_G12_CTRL0);
>> +	if (val & DMC_QOS_IRQ) {
>> +		dmc_g12_get_counters(info, counter);
>> +		/* clear irq flags */
>> +		writel(val, info->ddr_reg[0] + DMC_MON_G12_CTRL0);
>> +		ret = 0;
>> +	}
>> +	return ret;
>> +}
>> +
>> +static struct dmc_pmu_hw_ops g12_ops = {
> static const?
Yes, I will modify it.
>
>> +	.enable		= dmc_g12_counter_enable,
>> +	.disable	= dmc_g12_counter_disable,
>> +	.irq_handler	= dmc_g12_irq_handler,
>> +	.get_counters	= dmc_g12_get_counters,
>> +	.config_axi_id	= dmc_g12_config_axi_id,
>> +};
>> +
>> +static int __init g12_ddr_pmu_probe(struct platform_device *pdev)
>> +{
>> +	struct ddr_pmu *pmu;
>> +
>> +	if (of_device_is_compatible(pdev->dev.of_node,
>> +				    "amlogic,g12a-ddr-pmu")) {
>> +		format_attr_nna.attr.mode = 0;
>> +		format_attr_gdc.attr.mode = 0;
>> +		format_attr_arm1.attr.mode = 0;
>> +		format_attr_mipi_isp.attr.mode = 0;
> No. That's not correct patter. You must use variant specific driver data.

Do you mean use of_device_id.data? Could your please give me an

example code in kernel source?

>
>> +	} else if (of_device_is_compatible(pdev->dev.of_node,
>> +					   "amlogic,sm1-ddr-pmu")) {
>> +		format_attr_gdc.attr.mode = 0;
>> +		format_attr_arm1.attr.mode = 0;
>> +		format_attr_mipi_isp.attr.mode = 0;
> No. That's not correct patter. You must use variant specific driver data.
>
>> +	}
>> +
>> +	pmu = devm_kzalloc(&pdev->dev, sizeof(struct ddr_pmu), GFP_KERNEL);
>> +	if (!pmu)
>> +		return -ENOMEM;
>> +
>> +	/*
>> +	 * G12 series Soc have single dmc controller and
>> +	 * 4x ddr bandwidth monitor channels
>> +	 */
>> +	pmu->info.dmc_nr = 1;
>> +	pmu->info.chann_nr = 4;
>> +	pmu->info.ops = &g12_ops;
>> +	pmu->info.fmt_attr = g12_pmu_format_attrs;
>> +
>> +	return meson_ddr_pmu_create(pdev, pmu);
>> +}
>> +
>> +static int __exit g12_ddr_pmu_remove(struct platform_device *pdev)
>> +{
>> +	meson_ddr_pmu_remove(pdev);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id meson_ddr_pmu_dt_match[] = {
>> +	{
>> +		.compatible = "amlogic,g12-ddr-pmu",
> Undocumented compatible. Did you run checkpatch and fix all the errors?

Yes, I run "./scripts/checkpatch --strict *.patch", and no errors/warnings.

Any other options should be used to check strictly?

I think it could be removed.

>
>> +	},
>> +	{
>> +		.compatible = "amlogic,g12a-ddr-pmu",
>> +	},
>> +	{
>> +		.compatible = "amlogic,g12b-ddr-pmu",
>> +	},
>> +	{
>> +		.compatible = "amlogic,sm1-ddr-pmu",
> Why four different entries for the same devices without driver data?
> This is confusing.
Do you mean use a common compatible and different driver data?
>
>> +	},
>> +	{}
>> +};
>> +
>> +static struct platform_driver g12_ddr_pmu_driver = {
>> +	.driver = {
>> +		.name = "amlogic,ddr-pmu",
>> +		.of_match_table = meson_ddr_pmu_dt_match,
>> +	},
>> +	.remove = __exit_p(g12_ddr_pmu_remove),
> You made the driver non-hotpluggable - why?
> In the same time it is still unbindable, whis is a bit confusing. If you
> can unbind it, you should be able to hot-unplug it.
Sorry, I couldn't know why the driver is non-hotpluggable. Could you 
tell the detail?
>> +};
>> +
>> +module_platform_driver_probe(g12_ddr_pmu_driver, g12_ddr_pmu_probe);
>> +MODULE_AUTHOR("Jiucheng Xu");
>> +MODULE_LICENSE("GPL");
>> +MODULE_DESCRIPTION("Amlogic G12 series SoC DDR PMU");
>> diff --git a/include/soc/amlogic/meson_ddr_pmu.h b/include/soc/amlogic/meson_ddr_pmu.h
>> new file mode 100644
>> index 000000000000..882efe3c2f58
>> --- /dev/null
>> +++ b/include/soc/amlogic/meson_ddr_pmu.h
>> @@ -0,0 +1,76 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
>> + */
>> +
>> +#ifndef __MESON_DDR_PMU_H__
>> +#define __MESON_DDR_PMU_H__
>> +
>> +#define MAX_CHANNEL_NUM		8
>> +
>> +enum {
>> +	ALL_CHAN_COUNTER_ID,
>> +	CHAN1_COUNTER_ID,
>> +	CHAN2_COUNTER_ID,
>> +	CHAN3_COUNTER_ID,
>> +	CHAN4_COUNTER_ID,
>> +	CHAN5_COUNTER_ID,
>> +	CHAN6_COUNTER_ID,
>> +	CHAN7_COUNTER_ID,
>> +	CHAN8_COUNTER_ID,
>> +	COUNTER_MAX_ID,
>> +};
>> +
>> +struct dmc_hw_info;
>> +
>> +struct dmc_counter {
>> +	u64 all_cnt;	/* The count of all requests come in/out ddr controller */
>> +	union {
>> +		u64 all_req;
>> +		struct {
>> +			u64 all_idle_cnt;
>> +			u64 all_16bit_cnt;
>> +		};
>> +	};
>> +	u64 channel_cnt[MAX_CHANNEL_NUM]; /* To save a DMC bandwidth-monitor channel counter */
>> +};
>> +
>> +struct dmc_pmu_hw_ops {
>> +	void (*enable)(struct dmc_hw_info *info);
>> +	void (*disable)(struct dmc_hw_info *info);
>> +	/* Bind an axi line to a bandwidth-monitor channel */
>> +	void (*config_axi_id)(struct dmc_hw_info *info, int axi_id, int chann);
>> +	int (*irq_handler)(struct dmc_hw_info *info,
>> +			   struct dmc_counter *counter);
>> +	void (*get_counters)(struct dmc_hw_info *info,
>> +			     struct dmc_counter *counter);
>> +};
>> +
>> +struct dmc_hw_info {
>> +	struct dmc_pmu_hw_ops *ops;
>> +	void __iomem *ddr_reg[4];
>> +	unsigned long timer_value;	/* Timer value in TIMER register */
>> +	void __iomem *pll_reg;
>> +	int irq_num;			/* irq vector number */
>> +	int dmc_nr;			/* The number of dmc controller */
>> +	int chann_nr;			/* The number of dmc bandwidth monitor channels */
>> +	int id;				/* The number of supported channels */
>> +	struct attribute **fmt_attr;
>> +};
>> +
>> +struct ddr_pmu {
>> +	struct pmu pmu;
>> +	struct dmc_hw_info info;
>> +	struct dmc_counter counters;	/* save counters from hw */
>> +	bool pmu_enabled;
>> +	struct device *dev;
>> +	char *name;
>> +	struct hlist_node node;
>> +	enum cpuhp_state cpuhp_state;
>> +	int cpu;			/* for cpu hotplug */
>> +};
> Linux-wide headers should not include your private data structures.
> Entier header looks unused - should be made private.
Do you mean the header should be in driver dir, or the structures should 
be within .c file?
>
> Best regards,
> Krzysztof
>
-- 
Thanks,
Jiucheng

Re: [PATCH v4 3/4] arm64: dts: meson: Add DDR PMU node

[Jiucheng Xu]

On 2022/8/5 16:22, Krzysztof Kozlowski wrote:
> [ EXTERNAL EMAIL ]
>
> On 05/08/2022 09:14, Jiucheng Xu wrote:
>> Add DDR PMU device node for G12 series SoC
>>
>> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
>> ---
>> Changes v3 -> v4:
>>    - No change
>>
>> Changes v2 -> v3:
>>    - No change
>>
>> Changes v1 -> v2:
>>    - Remove model, dmc_nr, chann_nr properties
>>    - Add g12a-ddr-pmu, g12b-ddr-pmu, sm1-ddr-pmu compatibles as
>>      identifier
>> ---
>>   arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi | 7 +++++++
>>   arch/arm64/boot/dts/amlogic/meson-g12a.dtsi       | 4 ++++
>>   arch/arm64/boot/dts/amlogic/meson-g12b.dtsi       | 4 ++++
>>   arch/arm64/boot/dts/amlogic/meson-sm1.dtsi        | 4 ++++
>>   4 files changed, 19 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
>> index 45947c1031c4..7e556fe575be 100644
>> --- a/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
>> +++ b/arch/arm64/boot/dts/amlogic/meson-g12-common.dtsi
>> @@ -2146,6 +2146,13 @@ hdmi_tx_out: endpoint {
>>   			};
>>   		};
>>   
>> +		ddr_pmu: ddr_pmu@ff638000 {
> No underscores in node names.
>
> Node names should be generic, so pmu.
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
Okay, I will modify it.
>
>> +			compatible = "amlogic,g12-ddr-pmu";
>> +			reg = <0x0 0xff638000 0x0 0x100
>> +			       0x0 0xff638c00 0x0 0x100>;
>> +			interrupts = <GIC_SPI 52 IRQ_TYPE_EDGE_RISING>;
>> +		};
>> +
>>   		gic: interrupt-controller@ffc01000 {
>>   			compatible = "arm,gic-400";
>>   			reg = <0x0 0xffc01000 0 0x1000>,
>> diff --git a/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi b/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
>> index fb0ab27d1f64..4a32e081e70e 100644
>> --- a/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
>> +++ b/arch/arm64/boot/dts/amlogic/meson-g12a.dtsi
>> @@ -133,3 +133,7 @@ map1 {
>>   		};
>>   	};
>>   };
>> +
>> +&ddr_pmu {
>> +	compatible = "amlogic,g12a-ddr-pmu";
>> +};
> Adding nodes at the end causes conflicts. They should be added in some
> order...
Is alphabetical order okay?
>
> Best regards,
> Krzysztof
>
-- 
Thanks,
Jiucheng

Re: [PATCH v4 4/4] dt-binding: perf: Add Amlogic DDR PMU

[Jiucheng Xu]

On 2022/8/5 16:21, Krzysztof Kozlowski wrote:
> [ EXTERNAL EMAIL ]
>
> On 05/08/2022 09:14, Jiucheng Xu wrote:
>> Add binding documentation for the Amlogic G12 series DDR
>> performance monitor unit.
>>
> Bindings go first in the series, before their implementation.
>
>> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
>> ---
>> Changes v3 -> v4:
>>    - Fix "$id: relative path/filename doesn't match actual path or
>>      filename" warning
>>
>> Changes v2 -> v3:
>>    - Remove oneOf
>>    - Add descriptions
>>    - Fix compiling warning
>>
>> Changes v1 -> v2:
>>    - Rename file, from aml_ddr_pmu.yaml to amlogic,g12_ddr_pmu.yaml
>>    - Delete "model", "dmc_nr", "chann_nr" new properties
>>    - Fix compiling error
>> ---
>>   .../bindings/perf/amlogic,g12-ddr-pmu.yaml    | 52 +++++++++++++++++++
>>   MAINTAINERS                                   |  1 +
>>   2 files changed, 53 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
>> new file mode 100644
>> index 000000000000..4d018574ffd1
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
>> @@ -0,0 +1,52 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/perf/amlogic,g12-ddr-pmu.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Amlogic G12 DDR performance monitor
>> +
>> +maintainers:
>> +  - Jiucheng Xu <jiucheng.xu@amlogic.com>
>> +
>> +description: |
>> +  Amlogic G12 series SoC integrate DDR bandwidth monitor.
>> +  A timer is inside and can generate interrupt when timeout.
>> +  The bandwidth is counted in the timer ISR. Different platform
>> +  has different subset of event format attribute.
>> +
>> +properties:
>> +  compatible:
>> +    items:
> You have only one item, so remove "items".
>
>> +      - enum:
>> +          - amlogic,g12b-ddr-pmu
>> +          - amlogic,g12a-ddr-pmu
>> +          - amlogic,sm1-ddr-pmu
>> +
>> +  reg:
>> +    items:
>> +      - description: Physical address of DMC bandwidth register
>> +          and size of the configuration address space.
> Skip obvious pieces, so only:
>
> description: DMC bandwidth register space
>
>> +      - description: Physical address of DMC PLL register and
>> +          size of the configuration address space.
> description: DMC PLL bandwidth register space
>
>
>> +
>> +  interrupts:
>> +    items:
>> +      - description: The IRQ of the inside timer timeout.
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - interrupts
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>> +    ddr_pmu@ff638000 {
> No underscores in node names, generic node names, so just "pmu".
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
>
>> +        compatible = "amlogic,g12a-ddr-pmu";
>> +        reg = <0xff638000 0x100
>> +               0xff638c00 0x100>;
> This is still not fixed. Binding says you have two items, but you
> declared here only one item.

Okay, I will change it as your comments.


> Best regards,
> Krzysztof
>
-- 
Thanks,
Jiucheng

Re: [PATCH v4 1/4] perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

[Krzysztof Kozlowski]

On 05/08/2022 11:55, Jiucheng Xu wrote:
>>> +static int __init g12_ddr_pmu_probe(struct platform_device *pdev)
>>> +{
>>> +	struct ddr_pmu *pmu;
>>> +
>>> +	if (of_device_is_compatible(pdev->dev.of_node,
>>> +				    "amlogic,g12a-ddr-pmu")) {
>>> +		format_attr_nna.attr.mode = 0;
>>> +		format_attr_gdc.attr.mode = 0;
>>> +		format_attr_arm1.attr.mode = 0;
>>> +		format_attr_mipi_isp.attr.mode = 0;
>> No. That's not correct patter. You must use variant specific driver data.
> 
> Do you mean use of_device_id.data? Could your please give me an
> 
> example code in kernel source?

90% of Linux kernel drivers?

> 
>>
>>> +	} else if (of_device_is_compatible(pdev->dev.of_node,
>>> +					   "amlogic,sm1-ddr-pmu")) {
>>> +		format_attr_gdc.attr.mode = 0;
>>> +		format_attr_arm1.attr.mode = 0;
>>> +		format_attr_mipi_isp.attr.mode = 0;
>> No. That's not correct patter. You must use variant specific driver data.
>>
>>> +	}
>>> +
>>> +	pmu = devm_kzalloc(&pdev->dev, sizeof(struct ddr_pmu), GFP_KERNEL);
>>> +	if (!pmu)
>>> +		return -ENOMEM;
>>> +
>>> +	/*
>>> +	 * G12 series Soc have single dmc controller and
>>> +	 * 4x ddr bandwidth monitor channels
>>> +	 */
>>> +	pmu->info.dmc_nr = 1;
>>> +	pmu->info.chann_nr = 4;
>>> +	pmu->info.ops = &g12_ops;
>>> +	pmu->info.fmt_attr = g12_pmu_format_attrs;
>>> +
>>> +	return meson_ddr_pmu_create(pdev, pmu);
>>> +}
>>> +
>>> +static int __exit g12_ddr_pmu_remove(struct platform_device *pdev)
>>> +{
>>> +	meson_ddr_pmu_remove(pdev);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static const struct of_device_id meson_ddr_pmu_dt_match[] = {
>>> +	{
>>> +		.compatible = "amlogic,g12-ddr-pmu",
>> Undocumented compatible. Did you run checkpatch and fix all the errors?
> 
> Yes, I run "./scripts/checkpatch --strict *.patch", and no errors/warnings.
> 
> Any other options should be used to check strictly?
> 
> I think it could be removed.

Either you document it or drop it. It anyway looks a bit odd -
unspecific (neither for g12a, nor for g12b).

> 
>>
>>> +	},
>>> +	{
>>> +		.compatible = "amlogic,g12a-ddr-pmu",
>>> +	},
>>> +	{
>>> +		.compatible = "amlogic,g12b-ddr-pmu",
>>> +	},
>>> +	{
>>> +		.compatible = "amlogic,sm1-ddr-pmu",
>> Why four different entries for the same devices without driver data?
>> This is confusing.
> Do you mean use a common compatible and different driver data?

What I meant is that current version this is useless and confusing.
Different devices have different compatibles with different driver data.
Same devices have just the same compatible (so same driver data). You
mixed two different approaches.

>>
>>> +	},
>>> +	{}
>>> +};
>>> +
>>> +static struct platform_driver g12_ddr_pmu_driver = {
>>> +	.driver = {
>>> +		.name = "amlogic,ddr-pmu",
>>> +		.of_match_table = meson_ddr_pmu_dt_match,
>>> +	},
>>> +	.remove = __exit_p(g12_ddr_pmu_remove),
>> You made the driver non-hotpluggable - why?
>> In the same time it is still unbindable, whis is a bit confusing. If you
>> can unbind it, you should be able to hot-unplug it.
> Sorry, I couldn't know why the driver is non-hotpluggable. Could you 
> tell the detail?

You used module_platform_driver_probe, so the one with documentation:
 /* non-hotpluggable platform devices may use this so that probe() and

  * its support may live in __init sections, conserving runtime memory.

  */



>>> +};
>>> +
>>> +module_platform_driver_probe(g12_ddr_pmu_driver, g12_ddr_pmu_probe);
>>> +MODULE_AUTHOR("Jiucheng Xu");
>>> +MODULE_LICENSE("GPL");
>>> +MODULE_DESCRIPTION("Amlogic G12 series SoC DDR PMU");
>>> diff --git a/include/soc/amlogic/meson_ddr_pmu.h b/include/soc/amlogic/meson_ddr_pmu.h
>>> new file mode 100644
>>> index 000000000000..882efe3c2f58
>>> --- /dev/null
>>> +++ b/include/soc/amlogic/meson_ddr_pmu.h
>>> @@ -0,0 +1,76 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>> +/*
>>> + * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
>>> + */
>>> +
>>> +#ifndef __MESON_DDR_PMU_H__
>>> +#define __MESON_DDR_PMU_H__
>>> +
>>> +#define MAX_CHANNEL_NUM		8
>>> +
>>> +enum {
>>> +	ALL_CHAN_COUNTER_ID,
>>> +	CHAN1_COUNTER_ID,
>>> +	CHAN2_COUNTER_ID,
>>> +	CHAN3_COUNTER_ID,
>>> +	CHAN4_COUNTER_ID,
>>> +	CHAN5_COUNTER_ID,
>>> +	CHAN6_COUNTER_ID,
>>> +	CHAN7_COUNTER_ID,
>>> +	CHAN8_COUNTER_ID,
>>> +	COUNTER_MAX_ID,
>>> +};
>>> +
>>> +struct dmc_hw_info;
>>> +
>>> +struct dmc_counter {
>>> +	u64 all_cnt;	/* The count of all requests come in/out ddr controller */
>>> +	union {
>>> +		u64 all_req;
>>> +		struct {
>>> +			u64 all_idle_cnt;
>>> +			u64 all_16bit_cnt;
>>> +		};
>>> +	};
>>> +	u64 channel_cnt[MAX_CHANNEL_NUM]; /* To save a DMC bandwidth-monitor channel counter */
>>> +};
>>> +
>>> +struct dmc_pmu_hw_ops {
>>> +	void (*enable)(struct dmc_hw_info *info);
>>> +	void (*disable)(struct dmc_hw_info *info);
>>> +	/* Bind an axi line to a bandwidth-monitor channel */
>>> +	void (*config_axi_id)(struct dmc_hw_info *info, int axi_id, int chann);
>>> +	int (*irq_handler)(struct dmc_hw_info *info,
>>> +			   struct dmc_counter *counter);
>>> +	void (*get_counters)(struct dmc_hw_info *info,
>>> +			     struct dmc_counter *counter);
>>> +};
>>> +
>>> +struct dmc_hw_info {
>>> +	struct dmc_pmu_hw_ops *ops;
>>> +	void __iomem *ddr_reg[4];
>>> +	unsigned long timer_value;	/* Timer value in TIMER register */
>>> +	void __iomem *pll_reg;
>>> +	int irq_num;			/* irq vector number */
>>> +	int dmc_nr;			/* The number of dmc controller */
>>> +	int chann_nr;			/* The number of dmc bandwidth monitor channels */
>>> +	int id;				/* The number of supported channels */
>>> +	struct attribute **fmt_attr;
>>> +};
>>> +
>>> +struct ddr_pmu {
>>> +	struct pmu pmu;
>>> +	struct dmc_hw_info info;
>>> +	struct dmc_counter counters;	/* save counters from hw */
>>> +	bool pmu_enabled;
>>> +	struct device *dev;
>>> +	char *name;
>>> +	struct hlist_node node;
>>> +	enum cpuhp_state cpuhp_state;
>>> +	int cpu;			/* for cpu hotplug */
>>> +};
>> Linux-wide headers should not include your private data structures.
>> Entier header looks unused - should be made private.
> Do you mean the header should be in driver dir, or the structures should 
> be within .c file?

This or that, up to you. Definitely not in include/linux/.


Best regards,
Krzysztof

Re: [PATCH v4 3/4] arm64: dts: meson: Add DDR PMU node

[Krzysztof Kozlowski]

On 05/08/2022 11:57, Jiucheng Xu wrote:
>>> +&ddr_pmu {
>>> +	compatible = "amlogic,g12a-ddr-pmu";
>>> +};
>> Adding nodes at the end causes conflicts. They should be added in some
>> order...
> Is alphabetical order okay?

Yes.


Best regards,
Krzysztof

Re: [PATCH v4 1/4] perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

[Jiucheng Xu]

On 2022/8/8 13:42, Krzysztof Kozlowski wrote:
> [ EXTERNAL EMAIL ]
>
> On 05/08/2022 11:55, Jiucheng Xu wrote:
>>>> +static int __init g12_ddr_pmu_probe(struct platform_device *pdev)
>>>> +{
>>>> +	struct ddr_pmu *pmu;
>>>> +
>>>> +	if (of_device_is_compatible(pdev->dev.of_node,
>>>> +				    "amlogic,g12a-ddr-pmu")) {
>>>> +		format_attr_nna.attr.mode = 0;
>>>> +		format_attr_gdc.attr.mode = 0;
>>>> +		format_attr_arm1.attr.mode = 0;
>>>> +		format_attr_mipi_isp.attr.mode = 0;
>>> No. That's not correct patter. You must use variant specific driver data.
>> Do you mean use of_device_id.data? Could your please give me an
>>
>> example code in kernel source?
> 90% of Linux kernel drivers?
>
>>>> +	},
>>>> +	{
>>>> +		.compatible = "amlogic,g12a-ddr-pmu",
>>>> +	},
>>>> +	{
>>>> +		.compatible = "amlogic,g12b-ddr-pmu",
>>>> +	},
>>>> +	{
>>>> +		.compatible = "amlogic,sm1-ddr-pmu",
>>> Why four different entries for the same devices without driver data?
>>> This is confusing.
>> Do you mean use a common compatible and different driver data?
> What I meant is that current version this is useless and confusing.
> Different devices have different compatibles with different driver data.
> Same devices have just the same compatible (so same driver data). You
> mixed two different approaches.

Does the driver data must be necessary? Although G12A, G12B and SM1 are 
different devices,

but they have the same control interface. The only difference is that 
G12B has

4 extra modules be supported than G12A.

>
>>>> +	},
>>>> +	{}
>>>> +};
>>>> +
>>>> +static struct platform_driver g12_ddr_pmu_driver = {
>>>> +	.driver = {
>>>> +		.name = "amlogic,ddr-pmu",
>>>> +		.of_match_table = meson_ddr_pmu_dt_match,
>>>> +	},
>>>> +	.remove = __exit_p(g12_ddr_pmu_remove),
>>> You made the driver non-hotpluggable - why?
>>> In the same time it is still unbindable, whis is a bit confusing. If you
>>> can unbind it, you should be able to hot-unplug it.
>> Sorry, I couldn't know why the driver is non-hotpluggable. Could you
>> tell the detail?
> You used module_platform_driver_probe, so the one with documentation:
>   /* non-hotpluggable platform devices may use this so that probe() and
>
>    * its support may live in __init sections, conserving runtime memory.
>
>    */

Okay, module_platform_driver_probe（) was suggested by Robin Murphy 
<robin.murphy@arm.com>,

but you gave the reason. module_platform_driver() is okay?

>
>
>>>> +};
>>>> +
>>>> +module_platform_driver_probe(g12_ddr_pmu_driver, g12_ddr_pmu_probe);
>>>> +MODULE_AUTHOR("Jiucheng Xu");
>>>> +MODULE_LICENSE("GPL");
>>>> +MODULE_DESCRIPTION("Amlogic G12 series SoC DDR PMU");
>>>> diff --git a/include/soc/amlogic/meson_ddr_pmu.h b/include/soc/amlogic/meson_ddr_pmu.h
>>>> new file mode 100644
>>>> index 000000000000..882efe3c2f58
>>>> --- /dev/null
>>>> +++ b/include/soc/amlogic/meson_ddr_pmu.h
>>>> @@ -0,0 +1,76 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/*
>>>> + * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
>>>> + */
>>>> +
>>>> +#ifndef __MESON_DDR_PMU_H__
>>>> +#define __MESON_DDR_PMU_H__
>>>> +
>>>> +#define MAX_CHANNEL_NUM		8
>>>> +
>>>> +enum {
>>>> +	ALL_CHAN_COUNTER_ID,
>>>> +	CHAN1_COUNTER_ID,
>>>> +	CHAN2_COUNTER_ID,
>>>> +	CHAN3_COUNTER_ID,
>>>> +	CHAN4_COUNTER_ID,
>>>> +	CHAN5_COUNTER_ID,
>>>> +	CHAN6_COUNTER_ID,
>>>> +	CHAN7_COUNTER_ID,
>>>> +	CHAN8_COUNTER_ID,
>>>> +	COUNTER_MAX_ID,
>>>> +};
>>>> +
>>>> +struct dmc_hw_info;
>>>> +
>>>> +struct dmc_counter {
>>>> +	u64 all_cnt;	/* The count of all requests come in/out ddr controller */
>>>> +	union {
>>>> +		u64 all_req;
>>>> +		struct {
>>>> +			u64 all_idle_cnt;
>>>> +			u64 all_16bit_cnt;
>>>> +		};
>>>> +	};
>>>> +	u64 channel_cnt[MAX_CHANNEL_NUM]; /* To save a DMC bandwidth-monitor channel counter */
>>>> +};
>>>> +
>>>> +struct dmc_pmu_hw_ops {
>>>> +	void (*enable)(struct dmc_hw_info *info);
>>>> +	void (*disable)(struct dmc_hw_info *info);
>>>> +	/* Bind an axi line to a bandwidth-monitor channel */
>>>> +	void (*config_axi_id)(struct dmc_hw_info *info, int axi_id, int chann);
>>>> +	int (*irq_handler)(struct dmc_hw_info *info,
>>>> +			   struct dmc_counter *counter);
>>>> +	void (*get_counters)(struct dmc_hw_info *info,
>>>> +			     struct dmc_counter *counter);
>>>> +};
>>>> +
>>>> +struct dmc_hw_info {
>>>> +	struct dmc_pmu_hw_ops *ops;
>>>> +	void __iomem *ddr_reg[4];
>>>> +	unsigned long timer_value;	/* Timer value in TIMER register */
>>>> +	void __iomem *pll_reg;
>>>> +	int irq_num;			/* irq vector number */
>>>> +	int dmc_nr;			/* The number of dmc controller */
>>>> +	int chann_nr;			/* The number of dmc bandwidth monitor channels */
>>>> +	int id;				/* The number of supported channels */
>>>> +	struct attribute **fmt_attr;
>>>> +};
>>>> +
>>>> +struct ddr_pmu {
>>>> +	struct pmu pmu;
>>>> +	struct dmc_hw_info info;
>>>> +	struct dmc_counter counters;	/* save counters from hw */
>>>> +	bool pmu_enabled;
>>>> +	struct device *dev;
>>>> +	char *name;
>>>> +	struct hlist_node node;
>>>> +	enum cpuhp_state cpuhp_state;
>>>> +	int cpu;			/* for cpu hotplug */
>>>> +};
>>> Linux-wide headers should not include your private data structures.
>>> Entier header looks unused - should be made private.
>> Do you mean the header should be in driver dir, or the structures should
>> be within .c file?
> This or that, up to you. Definitely not in include/linux/.

I see other PMU drivers' header are in include/soc/xxx/. I just follow them.

meson G12 series SoC DDR PMU driver is the first PMU driver got upstream,

and other series will be got upstream in the future. So I think the 
structures are public.

Does this make sense?

>
>
> Best regards,
> Krzysztof
>
-- 
Thanks,
Jiucheng

Re: [PATCH v4 2/4] docs/perf: Add documentation for the Amlogic G12 DDR PMU

[kernel test robot]

Hi Jiucheng,

I love your patch! Perhaps something to improve:

[auto build test WARNING on robh/for-next]
[also build test WARNING on arm/for-next arm64/for-next/core clk/clk-next kvmarm/next rockchip/for-next shawnguo/for-next soc/for-next linus/master v5.19 next-20220808]
[cannot apply to xilinx-xlnx/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Jiucheng-Xu/perf-amlogic-Add-support-for-Amlogic-meson-G12-SoC-DDR-PMU-driver/20220805-151704
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
reproduce: make htmldocs

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> Documentation/admin-guide/perf/meson-ddr-pmu.rst:2: WARNING: Explicit markup ends without a blank line; unexpected unindent.

vim +2 Documentation/admin-guide/perf/meson-ddr-pmu.rst

   > 2	===========================================================
     3	Amlogic SoC DDR Bandwidth Performance Monitoring Unit (PMU)
     4	===========================================================
     5	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

Re: [PATCH v4 2/4] docs/perf: Add documentation for the Amlogic G12 DDR PMU

[kernel test robot]

Hi Jiucheng,

I love your patch! Perhaps something to improve:

[auto build test WARNING on robh/for-next]
[also build test WARNING on arm/for-next arm64/for-next/core clk/clk-next kvmarm/next rockchip/for-next shawnguo/for-next soc/for-next linus/master v5.19 next-20220812]
[cannot apply to xilinx-xlnx/master keystone/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Jiucheng-Xu/perf-amlogic-Add-support-for-Amlogic-meson-G12-SoC-DDR-PMU-driver/20220805-151704
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
reproduce: make htmldocs

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> Documentation/admin-guide/perf/meson-ddr-pmu.rst: WARNING: document isn't included in any toctree

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

Re: [PATCH v4 4/4] dt-binding: perf: Add Amlogic DDR PMU

[Jiucheng Xu]

On 2022/8/5 18:00, Jiucheng Xu wrote:
>
> On 2022/8/5 16:21, Krzysztof Kozlowski wrote:
>> [ EXTERNAL EMAIL ]
>>
>> On 05/08/2022 09:14, Jiucheng Xu wrote:
>>> Add binding documentation for the Amlogic G12 series DDR
>>> performance monitor unit.
>>>
>> Bindings go first in the series, before their implementation.
>>
>>> Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>
>>> ---
>>> Changes v3 -> v4:
>>>    - Fix "$id: relative path/filename doesn't match actual path or
>>>      filename" warning
>>>
>>> Changes v2 -> v3:
>>>    - Remove oneOf
>>>    - Add descriptions
>>>    - Fix compiling warning
>>>
>>> Changes v1 -> v2:
>>>    - Rename file, from aml_ddr_pmu.yaml to amlogic,g12_ddr_pmu.yaml
>>>    - Delete "model", "dmc_nr", "chann_nr" new properties
>>>    - Fix compiling error
>>> ---
>>>   .../bindings/perf/amlogic,g12-ddr-pmu.yaml    | 52 
>>> +++++++++++++++++++
>>>   MAINTAINERS                                   |  1 +
>>>   2 files changed, 53 insertions(+)
>>>   create mode 100644 
>>> Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
>>>
>>> diff --git 
>>> a/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml 
>>> b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
>>> new file mode 100644
>>> index 000000000000..4d018574ffd1
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
>>> @@ -0,0 +1,52 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/perf/amlogic,g12-ddr-pmu.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: Amlogic G12 DDR performance monitor
>>> +
>>> +maintainers:
>>> +  - Jiucheng Xu <jiucheng.xu@amlogic.com>
>>> +
>>> +description: |
>>> +  Amlogic G12 series SoC integrate DDR bandwidth monitor.
>>> +  A timer is inside and can generate interrupt when timeout.
>>> +  The bandwidth is counted in the timer ISR. Different platform
>>> +  has different subset of event format attribute.
>>> +
>>> +properties:
>>> +  compatible:
>>> +    items:
>> You have only one item, so remove "items".

Hi Krzysztof,

I have tried to remove "items", but error comes.

properties:
   compatible:
     - enum:
       - amlogic,g12a-ddr-pmu
       - amlogic,g12b-ddr-pmu
       - amlogic,sm1-ddr-pmu

Do I get misunderstand? I think the "item" is necessary.

>>
>>> +      - enum:
>>> +          - amlogic,g12b-ddr-pmu
>>> +          - amlogic,g12a-ddr-pmu
>>> +          - amlogic,sm1-ddr-pmu
>>> +
>>> +  reg:
>>> +    items:
>>> +      - description: Physical address of DMC bandwidth register
>>> +          and size of the configuration address space.
>> Skip obvious pieces, so only:
>>
>> description: DMC bandwidth register space
>>
>>> +      - description: Physical address of DMC PLL register and
>>> +          size of the configuration address space.
>> description: DMC PLL bandwidth register space
>>
>>
>>> +
>>> +  interrupts:
>>> +    items:
>>> +      - description: The IRQ of the inside timer timeout.
>>> +
>>> +required:
>>> +  - compatible
>>> +  - reg
>>> +  - interrupts
>>> +
>>> +additionalProperties: false
>>> +
>>> +examples:
>>> +  - |
>>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>>> +    ddr_pmu@ff638000 {
>> No underscores in node names, generic node names, so just "pmu".
>> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation 
>>
>>
>>> +        compatible = "amlogic,g12a-ddr-pmu";
>>> +        reg = <0xff638000 0x100
>>> +               0xff638c00 0x100>;
>> This is still not fixed. Binding says you have two items, but you
>> declared here only one item.
>
> Okay, I will change it as your comments.
>
>
>> Best regards,
>> Krzysztof
>>
-- 
Thanks,
Jiucheng

Re: [PATCH v4 4/4] dt-binding: perf: Add Amlogic DDR PMU

[Krzysztof Kozlowski]

On 15/08/2022 12:04, Jiucheng Xu wrote:
>>>> +properties:
>>>> +  compatible:
>>>> +    items:
>>> You have only one item, so remove "items".
> 
> Hi Krzysztof,
> 
> I have tried to remove "items", but error comes.
> 
> properties:
>    compatible:
>      - enum:
>        - amlogic,g12a-ddr-pmu
>        - amlogic,g12b-ddr-pmu
>        - amlogic,sm1-ddr-pmu
> 
> Do I get misunderstand? I think the "item" is necessary.

And how other bindings are doing it?

Best regards,
Krzysztof