diff options
-rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc-core.c | 28 |
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) |