diff options
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-etm4x.c')
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-etm4x.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index 78cb3b8881fa..b0141ba7b741 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -181,6 +181,12 @@ static void etm4_enable_hw(void *info) if (coresight_timeout(drvdata->base, TRCSTATR, TRCSTATR_IDLE_BIT, 0)) dev_err(drvdata->dev, "timeout while waiting for Idle Trace Status\n"); + /* + * As recommended by section 4.3.7 ("Synchronization when using the + * memory-mapped interface") of ARM IHI 0064D + */ + dsb(sy); + isb(); CS_LOCK(drvdata->base); @@ -331,8 +337,12 @@ static void etm4_disable_hw(void *info) /* EN, bit[0] Trace unit enable bit */ control &= ~0x1; - /* make sure everything completes before disabling */ - mb(); + /* + * Make sure everything completes before disabling, as recommended + * by section 7.3.77 ("TRCVICTLR, ViewInst Main Control Register, + * SSTATUS") of ARM IHI 0064D + */ + dsb(sy); isb(); writel_relaxed(control, drvdata->base + TRCPRGCTLR); |