[PATCH v2 1/3] coresight: tmc: Make memory width mask computation into a function

From: Mathieu Poirier
Date: Mon Aug 26 2019 - 15:46:17 EST


Make the computation of a memory mask representing the width of the memory
bus into a function so that it can be re-used by the ETR driver.

Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
.../hwtracing/coresight/coresight-tmc-etf.c | 23 ++-------------
drivers/hwtracing/coresight/coresight-tmc.c | 28 +++++++++++++++++++
drivers/hwtracing/coresight/coresight-tmc.h | 1 +
3 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 23b7ff00af5c..807416b75ecc 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -479,30 +479,11 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
* traces.
*/
if (!buf->snapshot && to_read > handle->size) {
- u32 mask = 0;
-
- /*
- * The value written to RRP must be byte-address aligned to
- * the width of the trace memory databus _and_ to a frame
- * boundary (16 byte), whichever is the biggest. For example,
- * for 32-bit, 64-bit and 128-bit wide trace memory, the four
- * LSBs must be 0s. For 256-bit wide trace memory, the five
- * LSBs must be 0s.
- */
- switch (drvdata->memwidth) {
- case TMC_MEM_INTF_WIDTH_32BITS:
- case TMC_MEM_INTF_WIDTH_64BITS:
- case TMC_MEM_INTF_WIDTH_128BITS:
- mask = GENMASK(31, 4);
- break;
- case TMC_MEM_INTF_WIDTH_256BITS:
- mask = GENMASK(31, 5);
- break;
- }
+ u32 mask = tmc_get_memwidth_mask(drvdata);

/*
* Make sure the new size is aligned in accordance with the
- * requirement explained above.
+ * requirement explained in function tmc_get_memwidth_mask().
*/
to_read = handle->size & mask;
/* Move the RAM read pointer up */
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index 3055bf8e2236..1cf82fa58289 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -70,6 +70,34 @@ void tmc_disable_hw(struct tmc_drvdata *drvdata)
writel_relaxed(0x0, drvdata->base + TMC_CTL);
}

+u32 tmc_get_memwidth_mask(struct tmc_drvdata *drvdata)
+{
+ u32 mask = 0;
+
+ /*
+ * When moving RRP or an offset address forward, the new values must
+ * be byte-address aligned to the width of the trace memory databus
+ * _and_ to a frame boundary (16 byte), whichever is the biggest. For
+ * example, for 32-bit, 64-bit and 128-bit wide trace memory, the four
+ * LSBs must be 0s. For 256-bit wide trace memory, the five LSBs must
+ * be 0s.
+ */
+ switch (drvdata->memwidth) {
+ case TMC_MEM_INTF_WIDTH_32BITS:
+ /* fallthrough */
+ case TMC_MEM_INTF_WIDTH_64BITS:
+ /* fallthrough */
+ case TMC_MEM_INTF_WIDTH_128BITS:
+ mask = GENMASK(31, 4);
+ break;
+ case TMC_MEM_INTF_WIDTH_256BITS:
+ mask = GENMASK(31, 5);
+ break;
+ }
+
+ return mask;
+}
+
static int tmc_read_prepare(struct tmc_drvdata *drvdata)
{
int ret = 0;
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 9dbcdf453e22..71de978575f3 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -255,6 +255,7 @@ void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata);
void tmc_flush_and_stop(struct tmc_drvdata *drvdata);
void tmc_enable_hw(struct tmc_drvdata *drvdata);
void tmc_disable_hw(struct tmc_drvdata *drvdata);
+u32 tmc_get_memwidth_mask(struct tmc_drvdata *drvdata);

/* ETB/ETF functions */
int tmc_read_prepare_etb(struct tmc_drvdata *drvdata);
--
2.17.1