diff options
author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2017-08-02 10:22:16 -0600 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-28 16:05:49 +0200 |
commit | f2e931a2deab1ab426085f0357285410644f2945 (patch) | |
tree | b61f1b5849575d47e3cb71f3d7bb9e0ab99ef611 /drivers/hwtracing/coresight/coresight-tmc-etr.c | |
parent | ebab6a7db2c599b5c29d033f3a20f86016d9a9b8 (diff) | |
download | op-kernel-dev-f2e931a2deab1ab426085f0357285410644f2945.zip op-kernel-dev-f2e931a2deab1ab426085f0357285410644f2945.tar.gz |
coresight tmc: Support for save-restore in ETR
The Coresight SoC 600 TMC ETR supports save-restore feature,
where the values of the RRP/RWP and STS.Full are retained
when it leaves the Disabled state. Hence, we must program the
RRP/RWP and STS.Full to a proper value. For now, set the RRP/RWP
to the base address of the buffer and clear the STS.Full register.
This can be later exploited for proper save-restore of ETR
trace contexts (e.g, perf).
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-tmc-etr.c')
-rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc-etr.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 40ddcf1..68fbc8f 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -22,7 +22,7 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata) { - u32 axictl; + u32 axictl, sts; /* Zero out the memory to help with debug */ memset(drvdata->vaddr, 0, drvdata->size); @@ -47,6 +47,17 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata) writel_relaxed(axictl, drvdata->base + TMC_AXICTL); tmc_write_dba(drvdata, drvdata->paddr); + /* + * If the TMC pointers must be programmed before the session, + * we have to set it properly (i.e, RRP/RWP to base address and + * STS to "not full"). + */ + if (tmc_etr_has_cap(drvdata, TMC_ETR_SAVE_RESTORE)) { + tmc_write_rrp(drvdata, drvdata->paddr); + tmc_write_rwp(drvdata, drvdata->paddr); + sts = readl_relaxed(drvdata->base + TMC_STS) & ~TMC_STS_FULL; + writel_relaxed(sts, drvdata->base + TMC_STS); + } writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT | |