Hi Robin,
On Tue, 5 Dec 2023, Robin Murphy wrote:
Hook up devicetree probing support. For now let's hope that people
implement PMIIDR properly and we don't need an override mechanism.
Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
drivers/perf/arm_cspmu/arm_cspmu.c | 71 +++++++++++++++++++++++-------
1 file changed, 56 insertions(+), 15 deletions(-)
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
index b64de4d800c7..80b5fc417ee3 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -27,6 +27,7 @@
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/of.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
@@ -309,6 +310,10 @@ static const char *arm_cspmu_get_name(const struct arm_cspmu *cspmu)
static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 };
dev = cspmu->dev;
+ if (!has_acpi_companion(dev))
Am I missing something since this doesn't work on top of v6.7-rc4?
The problem I see is that has_acpi_companion() calls
is_acpi_device_node(), which compares whether
fwnode->ops == &acpi_device_fwnode_ops;
However, the acpi/apmt code allocates fwnode by calling
acpi_alloc_fwnode_static(), which assigns &acpi_static_fwnode_ops
to ops.
I wonder though, if is_acpi_device_node() should check the static variant
too? :/
Cheers, Ilkka
+ return devm_kasprintf(dev, GFP_KERNEL, PMUNAME "_%u",
+ atomic_fetch_inc(&pmu_idx[0]));
+
apmt_node = arm_cspmu_apmt_node(dev);
pmu_type = apmt_node->type;
@@ -406,7 +411,6 @@ static struct arm_cspmu_impl_match *arm_cspmu_impl_match_get(u32 pmiidr)
static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
{
int ret = 0;
- struct acpi_apmt_node *apmt_node = arm_cspmu_apmt_node(cspmu->dev);
struct arm_cspmu_impl_match *match;
/* Start with a default PMU implementation */
@@ -425,8 +429,12 @@ static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
};
/* Firmware may override implementer/product ID from PMIIDR */
- if (apmt_node->impl_id)
- cspmu->impl.pmiidr = apmt_node->impl_id;
+ if (has_acpi_companion(cspmu->dev)) {
+ struct acpi_apmt_node *apmt_node = arm_cspmu_apmt_node(cspmu->dev);
+
+ if (apmt_node->impl_id)
+ cspmu->impl.pmiidr = apmt_node->impl_id;
+ }
/* Find implementer specific attribute ops. */
match = arm_cspmu_impl_match_get(cspmu->impl.pmiidr);
@@ -928,7 +936,6 @@ static void arm_cspmu_read(struct perf_event *event)
static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev)
{
- struct acpi_apmt_node *apmt_node;
struct arm_cspmu *cspmu;
struct device *dev = &pdev->dev;
@@ -939,8 +946,13 @@ static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev)
cspmu->dev = dev;
platform_set_drvdata(pdev, cspmu);
- apmt_node = arm_cspmu_apmt_node(dev);
- cspmu->has_atomic_dword = apmt_node->flags & ACPI_APMT_FLAGS_ATOMIC;
+ if (has_acpi_companion(dev)) {
+ struct acpi_apmt_node *apmt_node = arm_cspmu_apmt_node(dev);
+
+ cspmu->has_atomic_dword = apmt_node->flags & ACPI_APMT_FLAGS_ATOMIC;
+ } else {
+ cspmu->has_atomic_dword = device_property_read_bool(dev, "arm,64-bit-atomic");
+ }
return cspmu;
}
@@ -1133,11 +1145,6 @@ static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
}
}
- if (cpumask_empty(&cspmu->associated_cpus)) {
- dev_dbg(cspmu->dev, "No cpu associated with the PMU\n");
- return -ENODEV;
- }
-
return 0;
}
#else
@@ -1147,9 +1154,36 @@ static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu)
}
#endif
+static int arm_cspmu_of_get_cpus(struct arm_cspmu *cspmu)
+{
+ struct of_phandle_iterator it;
+ int ret, cpu;
+
+ of_for_each_phandle(&it, ret, cspmu->dev->of_node, "cpus", NULL, 0) {
+ cpu = of_cpu_node_to_id(it.node);
+ if (cpu < 0)
+ continue;
+ cpumask_set_cpu(cpu, &cspmu->associated_cpus);
+ }
+ return ret;
+}
+
static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
{
- return arm_cspmu_acpi_get_cpus(cspmu);
+ int ret = 0;
+
+ if (has_acpi_companion(cspmu->dev))
+ ret = arm_cspmu_acpi_get_cpus(cspmu);
+ else if (of_property_present(cspmu->dev->of_node, "cpus"))
+ ret = arm_cspmu_of_get_cpus(cspmu);
+ else
+ cpumask_copy(&cspmu->associated_cpus, cpu_possible_mask);
+
+ if (!ret && cpumask_empty(&cspmu->associated_cpus)) {
+ dev_dbg(cspmu->dev, "No cpu associated with the PMU\n");
+ ret = -ENODEV;
+ }
+ return ret;
}
static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu)
@@ -1246,11 +1280,18 @@ static const struct platform_device_id arm_cspmu_id[] = {
};
MODULE_DEVICE_TABLE(platform, arm_cspmu_id);
+static const struct of_device_id arm_cspmu_of_match[] = {
+ { .compatible = "arm,coresight-pmu" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, arm_cspmu_of_match);
+
static struct platform_driver arm_cspmu_driver = {
.driver = {
- .name = DRVNAME,
- .suppress_bind_attrs = true,
- },
+ .name = DRVNAME,
+ .of_match_table = arm_cspmu_of_match,
+ .suppress_bind_attrs = true,
+ },
.probe = arm_cspmu_device_probe,
.remove = arm_cspmu_device_remove,
.id_table = arm_cspmu_id,
--
2.39.2.101.g768bb238c484.dirty
