[PATCH v2 22/27] coresight: tmc-etr: Track if the device is coherent

From: Suzuki K Poulose
Date: Tue May 01 2018 - 05:12:21 EST


Track if the ETR is dma-coherent or not. This will be useful
in deciding if we should use software buffering for perf.

Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
drivers/hwtracing/coresight/coresight-tmc.c | 3 +++
drivers/hwtracing/coresight/coresight-tmc.h | 1 +
2 files changed, 4 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index 7adcde3..91a8f7b 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -359,6 +359,9 @@ static int tmc_etr_setup_caps(struct tmc_drvdata *drvdata,
if (!(devid & TMC_DEVID_NOSCAT) && tmc_etr_can_use_sg(drvdata))
tmc_etr_set_cap(drvdata, TMC_ETR_SG);

+ if (device_get_dma_attr(drvdata->dev) == DEV_DMA_COHERENT)
+ tmc_etr_set_cap(drvdata, TMC_ETR_COHERENT);
+
/* Check if the AXI address width is available */
if (devid & TMC_DEVID_AXIAW_VALID)
dma_mask = ((devid >> TMC_DEVID_AXIAW_SHIFT) &
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 1f6aa49..76a89a6 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -131,6 +131,7 @@ enum tmc_mem_intf_width {
* so we have to rely on PID of the IP to detect the functionality.
*/
#define TMC_ETR_SAVE_RESTORE (0x1U << 2)
+#define TMC_ETR_COHERENT (0x1U << 3)

/* Coresight SoC-600 TMC-ETR unadvertised capabilities */
#define CORESIGHT_SOC_600_ETR_CAPS \
--
2.7.4