The patch below does not apply to the 5.11-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f72896063396b0cb205cbf0fd76ec6ab3ca11c8a Mon Sep 17 00:00:00 2001

From: Suzuki K Poulose suzuki.poulose@arm.com Date: Mon, 1 Feb 2021 11:13:51 -0700 Subject: [PATCH] coresight: etm4x: Handle accesses to TRCSTALLCTLR

TRCSTALLCTLR register is only implemented if

TRCIDR3.STALLCTL == 0b1

Make sure the driver touches the register only it is implemented.

Link: https://lore.kernel.org/r/20210127184617.3684379-1-suzuki.poulose@arm.com Cc: stable@vger.kernel.org Cc: Mathieu Poirier mathieu.poirier@linaro.org Cc: Mike Leach mike.leach@linaro.org Cc: Leo Yan leo.yan@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Mathieu Poirier mathieu.poirier@linaro.org Link: https://lore.kernel.org/r/20210201181351.1475223-32-mathieu.poirier@linaro.o... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 473ab7480a36..5017d33ba4f5 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -306,7 +306,8 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata) etm4x_relaxed_write32(csa, 0x0, TRCAUXCTLR); etm4x_relaxed_write32(csa, config->eventctrl0, TRCEVENTCTL0R); etm4x_relaxed_write32(csa, config->eventctrl1, TRCEVENTCTL1R); - etm4x_relaxed_write32(csa, config->stall_ctrl, TRCSTALLCTLR); + if (drvdata->stallctl) + etm4x_relaxed_write32(csa, config->stall_ctrl, TRCSTALLCTLR); etm4x_relaxed_write32(csa, config->ts_ctrl, TRCTSCTLR); etm4x_relaxed_write32(csa, config->syncfreq, TRCSYNCPR); etm4x_relaxed_write32(csa, config->ccctlr, TRCCCCTLR); @@ -1463,7 +1464,8 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata) state->trcauxctlr = etm4x_read32(csa, TRCAUXCTLR); state->trceventctl0r = etm4x_read32(csa, TRCEVENTCTL0R); state->trceventctl1r = etm4x_read32(csa, TRCEVENTCTL1R); - state->trcstallctlr = etm4x_read32(csa, TRCSTALLCTLR); + if (drvdata->stallctl) + state->trcstallctlr = etm4x_read32(csa, TRCSTALLCTLR); state->trctsctlr = etm4x_read32(csa, TRCTSCTLR); state->trcsyncpr = etm4x_read32(csa, TRCSYNCPR); state->trcccctlr = etm4x_read32(csa, TRCCCCTLR); @@ -1575,7 +1577,8 @@ static void etm4_cpu_restore(struct etmv4_drvdata *drvdata) etm4x_relaxed_write32(csa, state->trcauxctlr, TRCAUXCTLR); etm4x_relaxed_write32(csa, state->trceventctl0r, TRCEVENTCTL0R); etm4x_relaxed_write32(csa, state->trceventctl1r, TRCEVENTCTL1R); - etm4x_relaxed_write32(csa, state->trcstallctlr, TRCSTALLCTLR); + if (drvdata->stallctl) + etm4x_relaxed_write32(csa, state->trcstallctlr, TRCSTALLCTLR); etm4x_relaxed_write32(csa, state->trctsctlr, TRCTSCTLR); etm4x_relaxed_write32(csa, state->trcsyncpr, TRCSYNCPR); etm4x_relaxed_write32(csa, state->trcccctlr, TRCCCCTLR); diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c index b646d53a3133..0995a10790f4 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c @@ -389,7 +389,7 @@ static ssize_t mode_store(struct device *dev, config->eventctrl1 &= ~BIT(12);

/* bit[8], Instruction stall bit */ - if (config->mode & ETM_MODE_ISTALL_EN) + if ((config->mode & ETM_MODE_ISTALL_EN) && (drvdata->stallctl == true)) config->stall_ctrl |= BIT(8); else config->stall_ctrl &= ~BIT(8);