On 23/01/2024 05:45, Anshuman Khandual wrote:
Instead of using AMBA private data field, extract the device name from AMBA pid based table lookup using new coresight_get_uci_data_from_amba() helper.
Cc: Suzuki K Poulose suzuki.poulose@arm.com Cc: Mike Leach mike.leach@linaro.org Cc: James Clark james.clark@arm.com Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-stm32@st-md-mailman.stormreply.com Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com
drivers/hwtracing/coresight/coresight-priv.h | 10 ++++++++++ drivers/hwtracing/coresight/coresight-stm.c | 14 +++++++++++++- 2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index 767076e07970..68cbb036cec8 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -221,6 +221,16 @@ static inline void *coresight_get_uci_data(const struct amba_id *id) return uci_id->data; } +static inline void *coresight_get_uci_data_from_amba(const struct amba_id *table, u32 pid) +{
- while (table->mask) {
if ((table->id & table->mask) == pid)
Why are we masking table->id ? table->id is a static value that the driver wants to check for "variants" of a given device. The table->mask is there to filter out the "irrelevant" bits of the PID that we read from the device. So this should instead be:
if ((table->mask & pid) == table->id)
return coresight_get_uci_data(table);table++;- };
- return NULL;
+}
- void coresight_release_platform_data(struct coresight_device *csdev, struct device *dev, struct coresight_platform_data *pdata);
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c index a1c27c901ad1..9cdca4f86cab 100644 --- a/drivers/hwtracing/coresight/coresight-stm.c +++ b/drivers/hwtracing/coresight/coresight-stm.c @@ -804,6 +804,18 @@ static void stm_init_generic_data(struct stm_drvdata *drvdata, drvdata->stm.set_options = stm_generic_set_options; } +#define STM_AMBA_MASK 0xfffff
+static const struct amba_id stm_ids[];
+static char *stm_csdev_name(struct coresight_device *csdev) +{
- u32 stm_pid = coresight_get_pid(&csdev->access) & STM_AMBA_MASK;
Similar to above:
Why do we apply a "custom" mask to the PID and later check the PID with that of the table->pid.
The way it is supposed work is :
(table->mask & dev_pid) == table->pid
the table->mask is there for a reason: i.e., to get the relevant bits from the device_pid and compare it against "the" expected value (table->pid).
Suzuki
- void *uci_data = coresight_get_uci_data_from_amba(stm_ids, stm_pid);
- return uci_data ? (char *)uci_data : "STM";
+}
- static int stm_probe(struct amba_device *adev, const struct amba_id *id) { int ret, trace_id;
@@ -900,7 +912,7 @@ static int stm_probe(struct amba_device *adev, const struct amba_id *id) pm_runtime_put(&adev->dev); dev_info(&drvdata->csdev->dev, "%s initialized\n",
(char *)coresight_get_uci_data(id));
stm_csdev_name(drvdata->csdev));cs_unregister: