From mboxrd@z Thu Jan 1 00:00:00 1970 From: mathieu.poirier@linaro.org (Mathieu Poirier) Date: Tue, 22 Mar 2016 14:23:10 -0600 Subject: [PATCH 02/14] coresight: tmc: waiting for TMCReady bit before programming In-Reply-To: <1458678202-3447-1-git-send-email-mathieu.poirier@linaro.org> References: <1458678202-3447-1-git-send-email-mathieu.poirier@linaro.org> Message-ID: <1458678202-3447-3-git-send-email-mathieu.poirier@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org According to the TRM before programming the TMC in circular buffer mode (and that for any configuration, ETB, ETR, ETF), the TMCReady bit in the status register has to be set. This patch adds a check to make sure the state machine is in a state where it can be configured, and complains otherwise. Signed-off-by: Mathieu Poirier --- drivers/hwtracing/coresight/coresight-tmc.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c index 8a9e4d789bd8..f4ba837a0810 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.c +++ b/drivers/hwtracing/coresight/coresight-tmc.c @@ -179,6 +179,9 @@ static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata) CS_UNLOCK(drvdata->base); + /* Wait for TMCSReady bit to be set */ + tmc_wait_for_tmcready(drvdata); + writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE); writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT | @@ -200,6 +203,9 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata) CS_UNLOCK(drvdata->base); + /* Wait for TMCSReady bit to be set */ + tmc_wait_for_tmcready(drvdata); + writel_relaxed(drvdata->size / 4, drvdata->base + TMC_RSZ); writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE); @@ -229,6 +235,9 @@ static void tmc_etf_enable_hw(struct tmc_drvdata *drvdata) { CS_UNLOCK(drvdata->base); + /* Wait for TMCSReady bit to be set */ + tmc_wait_for_tmcready(drvdata); + writel_relaxed(TMC_MODE_HARDWARE_FIFO, drvdata->base + TMC_MODE); writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI, drvdata->base + TMC_FFCR); -- 2.1.4