coresight: tmc: Make memory width mask computation into a function

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@linaro.org>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20190829202842.580-16-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 23b7ff0..807416b 100644 (file)
--- 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 3055bf8..1cf82fa 100644 (file)
--- 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 9dbcdf4..71de978 100644 (file)
--- 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);