kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

4 files changed, 972 insertions, 0 deletions

diff --git a/drivers/perf/amlogic/Kconfig b/drivers/perf/amlogic/Kconfig
new file mode 100644
index 000000000..f68db01a7
--- /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 000000000..d3ab2ac53
--- /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_g12.o
+
+meson_ddr_pmu_g12-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 000000000..c1e755c35
--- /dev/null
+++ b/drivers/perf/amlogic/meson_ddr_pmu_core.c
@@ -0,0 +1,564 @@
+// 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/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <soc/amlogic/meson_ddr_pmu.h>
+
+struct ddr_pmu {
+	struct pmu pmu;
+	struct dmc_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 */
+};
+
+#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 dmc_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.hw_info->enable(&pmu->info);
+
+	pmu->pmu_enabled = true;
+}
+
+static void dmc_pmu_disable(struct ddr_pmu *pmu)
+{
+	if (pmu->pmu_enabled)
+		pmu->info.hw_info->disable(&pmu->info);
+
+	pmu->pmu_enabled = false;
+}
+
+static void meson_ddr_set_axi_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;
+
+		pmu->info.hw_info->set_axi_filter(&pmu->info, 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;
+	int chann_nr = pmu->info.hw_info->chann_nr;
+
+	/* get the remain counters in register. */
+	pmu->info.hw_info->get_counters(&pmu->info, &dc);
+
+	ddr_cnt_addition(&sum_dc, &pmu->counters, &dc, 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;
+	u64 config2 = event->attr.config2;
+
+	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) + hweight64(config2) > 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;
+	u64 config2 = event->attr.config2;
+	int i;
+
+	for_each_set_bit(i,
+			 (const unsigned long *)&config1,
+			 BITS_PER_TYPE(config1))
+		meson_ddr_set_axi_filter(event, i);
+
+	for_each_set_bit(i,
+			 (const unsigned long *)&config2,
+			 BITS_PER_TYPE(config2))
+		meson_ddr_set_axi_filter(event, i + 64);
+
+	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,
+};
+
+static umode_t meson_ddr_perf_format_attr_visible(struct kobject *kobj,
+						  struct attribute *attr,
+						  int n)
+{
+	struct pmu *pmu = dev_get_drvdata(kobj_to_dev(kobj));
+	struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
+	const u64 *capability = ddr_pmu->info.hw_info->capability;
+	struct device_attribute *dev_attr;
+	int id;
+	char value[20]; // config1:xxx, 20 is enough
+
+	dev_attr = container_of(attr, struct device_attribute, attr);
+	dev_attr->show(NULL, NULL, value);
+
+	if (sscanf(value, "config1:%d", &id) == 1)
+		return capability[0] & (1ULL << id) ? attr->mode : 0;
+
+	if (sscanf(value, "config2:%d", &id) == 1)
+		return capability[1] & (1ULL << id) ? attr->mode : 0;
+
+	return attr->mode;
+}
+
+static struct attribute_group ddr_perf_format_attr_group = {
+	.name = "format",
+	.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_info *info = dev_id;
+	struct ddr_pmu *pmu;
+	struct dmc_counter counters, *sum_cnter;
+	int i;
+
+	pmu = dmc_info_to_pmu(info);
+
+	if (info->hw_info->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.hw_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->hw_info->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.hw_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)
+{
+	ddr_perf_format_attr_group.attrs = fmt_attr;
+}
+
+static int ddr_pmu_parse_dt(struct platform_device *pdev,
+			    struct dmc_info *info)
+{
+	void __iomem *base;
+	int i, ret;
+
+	info->hw_info = of_device_get_match_data(&pdev->dev);
+
+	for (i = 0; i < info->hw_info->dmc_nr; i++) {
+		/* resource 0 for ddr register base */
+		base = devm_platform_ioremap_resource(pdev, i);
+		if (IS_ERR(base))
+			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))
+		return PTR_ERR(base);
+
+	info->pll_reg = base;
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		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)
+		return ret;
+
+	return 0;
+}
+
+int meson_ddr_pmu_create(struct platform_device *pdev)
+{
+	int ret;
+	char *name;
+	struct ddr_pmu *pmu;
+
+	pmu = devm_kzalloc(&pdev->dev, sizeof(struct ddr_pmu), GFP_KERNEL);
+	if (!pmu)
+		return -ENOMEM;
+
+	*pmu = (struct ddr_pmu) {
+		.pmu = {
+			.module		= THIS_MODULE,
+			.parent		= &pdev->dev,
+			.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,
+		},
+	};
+
+	ret = ddr_pmu_parse_dt(pdev, &pmu->info);
+	if (ret < 0)
+		return ret;
+
+	fmt_attr_fill(pmu->info.hw_info->fmt_attr);
+
+	pmu->cpu = raw_smp_processor_id();
+
+	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME);
+	if (!name)
+		return -ENOMEM;
+
+	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, name, NULL,
+				      ddr_perf_offline_cpu);
+	if (ret < 0)
+		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)
+		goto cpuhp_instance_err;
+
+	fill_event_attr(pmu);
+
+	ret = perf_pmu_register(&pmu->pmu, name, -1);
+	if (ret)
+		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;
+}
+
+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;
+}
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 000000000..f33e9a456
--- /dev/null
+++ b/drivers/perf/amlogic/meson_g12_ddr_pmu.c
@@ -0,0 +1,393 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Amlogic, Inc. All rights reserved.
+ */
+
+#include <linux/err.h>
+#include <linux/io.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 <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		(0x0  << 2)
+#define DMC_MON_G12_CTRL1		(0x1  << 2)
+#define DMC_MON_G12_CTRL2		(0x2  << 2)
+#define DMC_MON_G12_CTRL3		(0x3  << 2)
+#define DMC_MON_G12_CTRL4		(0x4  << 2)
+#define DMC_MON_G12_CTRL5		(0x5  << 2)
+#define DMC_MON_G12_CTRL6		(0x6  << 2)
+#define DMC_MON_G12_CTRL7		(0x7  << 2)
+#define DMC_MON_G12_CTRL8		(0x8  << 2)
+
+#define DMC_MON_G12_ALL_REQ_CNT		(0x9  << 2)
+#define DMC_MON_G12_ALL_GRANT_CNT	(0xa  << 2)
+#define DMC_MON_G12_ONE_GRANT_CNT	(0xb  << 2)
+#define DMC_MON_G12_SEC_GRANT_CNT	(0xc  << 2)
+#define DMC_MON_G12_THD_GRANT_CNT	(0xd  << 2)
+#define DMC_MON_G12_FOR_GRANT_CNT	(0xe  << 2)
+#define DMC_MON_G12_TIMER		(0xf  << 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_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_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_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_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_set_axi_filter(struct dmc_info *info, int axi_id, int channel)
+{
+	if (channel > info->hw_info->chann_nr)
+		return;
+
+	dmc_g12_config_fiter(info, axi_id, channel);
+}
+
+static void dmc_g12_counter_disable(struct dmc_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->hw_info->chann_nr; i++)
+		dmc_g12_config_fiter(info, -1, i);
+}
+
+static void dmc_g12_get_counters(struct dmc_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->hw_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_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 const struct dmc_hw_info g12a_dmc_info = {
+	.enable		= dmc_g12_counter_enable,
+	.disable	= dmc_g12_counter_disable,
+	.irq_handler	= dmc_g12_irq_handler,
+	.get_counters	= dmc_g12_get_counters,
+	.set_axi_filter	= dmc_g12_set_axi_filter,
+
+	.dmc_nr = 1,
+	.chann_nr = 4,
+	.capability = {0X7EFF00FF03DF, 0},
+	.fmt_attr = g12_pmu_format_attrs,
+};
+
+static const struct dmc_hw_info g12b_dmc_info = {
+	.enable		= dmc_g12_counter_enable,
+	.disable	= dmc_g12_counter_disable,
+	.irq_handler	= dmc_g12_irq_handler,
+	.get_counters	= dmc_g12_get_counters,
+	.set_axi_filter	= dmc_g12_set_axi_filter,
+
+	.dmc_nr = 1,
+	.chann_nr = 4,
+	.capability = {0X7FFF00FF3FDF, 0},
+	.fmt_attr = g12_pmu_format_attrs,
+};
+
+static const struct dmc_hw_info sm1_dmc_info = {
+	.enable		= dmc_g12_counter_enable,
+	.disable	= dmc_g12_counter_disable,
+	.irq_handler	= dmc_g12_irq_handler,
+	.get_counters	= dmc_g12_get_counters,
+	.set_axi_filter	= dmc_g12_set_axi_filter,
+
+	.dmc_nr = 1,
+	.chann_nr = 4,
+	.capability = {0X7EFF00FF07DF, 0},
+	.fmt_attr = g12_pmu_format_attrs,
+};
+
+static int g12_ddr_pmu_probe(struct platform_device *pdev)
+{
+	return meson_ddr_pmu_create(pdev);
+}
+
+static void g12_ddr_pmu_remove(struct platform_device *pdev)
+{
+	meson_ddr_pmu_remove(pdev);
+}
+
+static const struct of_device_id meson_ddr_pmu_dt_match[] = {
+	{
+		.compatible = "amlogic,g12a-ddr-pmu",
+		.data = &g12a_dmc_info,
+	},
+	{
+		.compatible = "amlogic,g12b-ddr-pmu",
+		.data = &g12b_dmc_info,
+	},
+	{
+		.compatible = "amlogic,sm1-ddr-pmu",
+		.data = &sm1_dmc_info,
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, meson_ddr_pmu_dt_match);
+
+static struct platform_driver g12_ddr_pmu_driver = {
+	.probe = g12_ddr_pmu_probe,
+	.remove = g12_ddr_pmu_remove,
+
+	.driver = {
+		.name = "meson-g12-ddr-pmu",
+		.of_match_table = meson_ddr_pmu_dt_match,
+	},
+};
+
+module_platform_driver(g12_ddr_pmu_driver);
+MODULE_AUTHOR("Jiucheng Xu");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Amlogic G12 series SoC DDR PMU");