summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--drivers/hwtracing/coresight/coresight-tmc-core.c28
1 files changed, 27 insertions, 1 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 4b50d043ce04..741ce1748e75 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -4,6 +4,7 @@
* Description: CoreSight Trace Memory Controller driver
*/
+#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
@@ -362,7 +363,32 @@ static const struct attribute_group *coresight_etr_groups[] = {
static inline bool tmc_etr_can_use_sg(struct device *dev)
{
- return fwnode_property_present(dev->fwnode, "arm,scatter-gather");
+ int ret;
+ u8 val_u8;
+
+ /*
+ * Presence of the property 'arm,scatter-gather' is checked
+ * on the platform for the feature support, rather than its
+ * value.
+ */
+ if (is_of_node(dev->fwnode)) {
+ return fwnode_property_present(dev->fwnode, "arm,scatter-gather");
+ } else if (is_acpi_device_node(dev->fwnode)) {
+ /*
+ * TMC_DEVID_NOSCAT test in tmc_etr_setup_caps(), has already ensured
+ * this property is only checked for Coresight SoC 400 TMC configured
+ * as ETR.
+ */
+ ret = fwnode_property_read_u8(dev->fwnode, "arm-armhc97c-sg-enable", &val_u8);
+ if (!ret)
+ return !!val_u8;
+
+ if (fwnode_property_present(dev->fwnode, "arm,scatter-gather")) {
+ pr_warn_once("Deprecated ACPI property - arm,scatter-gather\n");
+ return true;
+ }
+ }
+ return false;
}
static inline bool tmc_etr_has_non_secure_access(struct tmc_drvdata *drvdata)