coresight: Add helper for inserting synchronization packets

Right now we open code filling the trace buffer with synchronization
packets when the circular buffer wraps around in different drivers.
Move this to a common place. While at it, clean up the barrier_pkt
array to strip off the trailing '\0'.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 320d29d..306119e 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -195,7 +195,6 @@ static void etb_dump_hw(struct etb_drvdata *drvdata)
        bool lost = false;
        int i;
        u8 *buf_ptr;
-       const u32 *barrier;
        u32 read_data, depth;
        u32 read_ptr, write_ptr;
        u32 frame_off, frame_endoff;
@@ -226,19 +225,16 @@ static void etb_dump_hw(struct etb_drvdata *drvdata)
 
        depth = drvdata->buffer_depth;
        buf_ptr = drvdata->buf;
-       barrier = barrier_pkt;
        for (i = 0; i < depth; i++) {
                read_data = readl_relaxed(drvdata->base +
                                          ETB_RAM_READ_DATA_REG);
-               if (lost && *barrier) {
-                       read_data = *barrier;
-                       barrier++;
-               }
-
                *(u32 *)buf_ptr = read_data;
                buf_ptr += 4;
        }
 
+       if (lost)
+               coresight_insert_barrier_packet(drvdata->buf);
+
        if (frame_off) {
                buf_ptr -= (frame_endoff * 4);
                for (i = 0; i < frame_endoff; i++) {
@@ -447,7 +443,7 @@ static void etb_update_buffer(struct coresight_device *csdev,
                buf_ptr = buf->data_pages[cur] + offset;
                read_data = readl_relaxed(drvdata->base +
                                          ETB_RAM_READ_DATA_REG);
-               if (lost && *barrier) {
+               if (lost && i < CORESIGHT_BARRIER_PKT_SIZE) {
                        read_data = *barrier;
                        barrier++;
                }

diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index 0e5a74d..1a6cf35 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -57,7 +57,8 @@ static DEVICE_ATTR_RO(name)
 #define coresight_simple_reg64(type, name, lo_off, hi_off)             \
        __coresight_simple_func(type, NULL, name, lo_off, hi_off)
 
-extern const u32 barrier_pkt[5];
+extern const u32 barrier_pkt[4];
+#define CORESIGHT_BARRIER_PKT_SIZE (sizeof(barrier_pkt))
 
 enum etm_addr_type {
        ETM_ADDR_TYPE_NONE,
@@ -91,6 +92,13 @@ struct cs_buffers {
        void                    **data_pages;
 };
 
+static inline void coresight_insert_barrier_packet(void *buf)
+{
+       if (buf)
+               memcpy(buf, barrier_pkt, CORESIGHT_BARRIER_PKT_SIZE);
+}
+
+
 static inline void CS_LOCK(void __iomem *addr)
 {
        do {

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 73160cd..0549249 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -32,39 +32,28 @@ static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 
 static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
 {
-       bool lost = false;
        char *bufp;
-       const u32 *barrier;
-       u32 read_data, status;
+       u32 read_data, lost;
        int i;
 
-       /*
-        * Get a hold of the status register and see if a wrap around
-        * has occurred.
-        */
-       status = readl_relaxed(drvdata->base + TMC_STS);
-       if (status & TMC_STS_FULL)
-               lost = true;
-
+       /* Check if the buffer wrapped around. */
+       lost = readl_relaxed(drvdata->base + TMC_STS) & TMC_STS_FULL;
        bufp = drvdata->buf;
        drvdata->len = 0;
-       barrier = barrier_pkt;
        while (1) {
                for (i = 0; i < drvdata->memwidth; i++) {
                        read_data = readl_relaxed(drvdata->base + TMC_RRD);
                        if (read_data == 0xFFFFFFFF)
-                               return;
-
-                       if (lost && *barrier) {
-                               read_data = *barrier;
-                               barrier++;
-                       }
-
+                               goto done;
                        memcpy(bufp, &read_data, 4);
                        bufp += 4;
                        drvdata->len += 4;
                }
        }
+done:
+       if (lost)
+               coresight_insert_barrier_packet(drvdata->buf);
+       return;
 }
 
 static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 18c9a18..04206ff 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -91,9 +91,7 @@ ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata,
 
 static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
 {
-       const u32 *barrier;
        u32 val;
-       u32 *temp;
        u64 rwp;
 
        rwp = tmc_read_rwp(drvdata);
@@ -106,16 +104,7 @@ static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
        if (val & TMC_STS_FULL) {
                drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr;
                drvdata->len = drvdata->size;
-
-               barrier = barrier_pkt;
-               temp = (u32 *)drvdata->buf;
-
-               while (*barrier) {
-                       *temp = *barrier;
-                       temp++;
-                       barrier++;
-               }
-
+               coresight_insert_barrier_packet(drvdata->buf);
        } else {
                drvdata->buf = drvdata->vaddr;
                drvdata->len = rwp - drvdata->paddr;

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 29e834a..4969b32 100644 (file)
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -51,8 +51,7 @@ static struct list_head *stm_path;
  * beginning of the data collected in a buffer.  That way the decoder knows that
  * it needs to look for another sync sequence.
  */
-const u32 barrier_pkt[5] = {0x7fffffff, 0x7fffffff,
-                           0x7fffffff, 0x7fffffff, 0x0};
+const u32 barrier_pkt[4] = {0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff};
 
 static int coresight_id_match(struct device *dev, void *data)
 {