On 19/05/2023 06:21, Anshuman Khandual wrote:
Coresight device pid can be retrieved from its iomem base address, which is
stored in 'struct etm4x_drvdata'. This drops pid argument from etm4_probe()
and 'struct etm4_init_arg'. Instead etm4_check_arch_features() derives the
coresight device pid with a new helper coresight_get_pid(), right before it
is consumed in etm4_hisi_match_pid().
Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: Mike Leach <mike.leach@xxxxxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: coresight@xxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
.../coresight/coresight-etm4x-core.c | 29 ++++++++++---------
include/linux/coresight.h | 12 ++++++++
2 files changed, 27 insertions(+), 14 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 748d2ef53cb0..914ef6eb85d1 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -66,7 +66,6 @@ static u64 etm4_get_access_type(struct etmv4_config *config);
static enum cpuhp_state hp_online;
struct etm4_init_arg {
- unsigned int pid;
struct device *dev;
struct csdev_access *csa;
};
@@ -370,9 +369,17 @@ static void etm4_disable_arch_specific(struct etmv4_drvdata *drvdata)
}
static void etm4_check_arch_features(struct etmv4_drvdata *drvdata,
- unsigned int id)
+ struct csdev_access *csa)
{
- if (etm4_hisi_match_pid(id))
+ /*
+ * coresight_get_pid() fetches device PID from the iomem
+ * register based accesses, which cannot be performed on
+ * system instruction based devices.
+ */
Minor nit: Please fix the comment to say something like :
/*
* TRCPIDR* registers are not required for ETMs with system
* instructions. They must be identified by the MIDR+REVIDRs.
* Skip the TRCPID checks for now.
*/
Rest looks good to me.
Suzuki