From: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> To: Mathieu Poirier <mathieu.poirier@linaro.org>, Suzuki K Poulose <suzuki.poulose@arm.com>, Mike Leach <mike.leach@linaro.org>, devicetree@vger.kernel.org, Rob Herring <robh+dt@kernel.org> Cc: Stephen Boyd <swboyd@chromium.org>, Leo Yan <leo.yan@linaro.org>, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Tingwei Zhang <tingwei@codeaurora.org>, coresight@lists.linaro.org, Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Subject: [PATCHv2 1/2] coresight: etm4x: Add support to skip trace unit power up Date: Fri, 15 May 2020 01:27:55 +0530 [thread overview] Message-ID: <7f2aeb36979ebfef30ea8356e6aa3111a611d6b5.1589485594.git.saiprakash.ranjan@codeaurora.org> (raw) In-Reply-To: <cover.1589485594.git.saiprakash.ranjan@codeaurora.org> From: Tingwei Zhang <tingwei@codeaurora.org> On some Qualcomm Technologies Inc. SoCs like SC7180, there exists a hardware errata where the APSS (Application Processor SubSystem)/CPU watchdog counter is stopped when the trace unit power up ETM register is set (TRCPDCR.PU = 1). Since the ETMs share the same power domain as that of respective CPU cores, they are powered on when the CPU core is powered on. So we can skip powering up of trace unit after checking for this errata via new property called "qcom,skip-power-up". Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org> Co-developed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> --- drivers/hwtracing/coresight/coresight-etm4x.c | 27 ++++++++++++------- drivers/hwtracing/coresight/coresight-etm4x.h | 3 +++ 2 files changed, 20 insertions(+), 10 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index fb0f5f4f3a91..b38214326fa4 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -196,12 +196,14 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata) writel_relaxed(config->vmid_mask0, drvdata->base + TRCVMIDCCTLR0); writel_relaxed(config->vmid_mask1, drvdata->base + TRCVMIDCCTLR1); - /* - * Request to keep the trace unit powered and also - * emulation of powerdown - */ - writel_relaxed(readl_relaxed(drvdata->base + TRCPDCR) | TRCPDCR_PU, - drvdata->base + TRCPDCR); + if (!drvdata->skip_power_up) { + /* + * Request to keep the trace unit powered and also + * emulation of powerdown + */ + writel_relaxed(readl_relaxed(drvdata->base + TRCPDCR) | TRCPDCR_PU, + drvdata->base + TRCPDCR); + } /* Enable the trace unit */ writel_relaxed(1, drvdata->base + TRCPRGCTLR); @@ -476,10 +478,12 @@ static void etm4_disable_hw(void *info) CS_UNLOCK(drvdata->base); - /* power can be removed from the trace unit now */ - control = readl_relaxed(drvdata->base + TRCPDCR); - control &= ~TRCPDCR_PU; - writel_relaxed(control, drvdata->base + TRCPDCR); + if (!drvdata->skip_power_up) { + /* power can be removed from the trace unit now */ + control = readl_relaxed(drvdata->base + TRCPDCR); + control &= ~TRCPDCR_PU; + writel_relaxed(control, drvdata->base + TRCPDCR); + } control = readl_relaxed(drvdata->base + TRCPRGCTLR); @@ -1429,6 +1433,9 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) return -ENOMEM; } + if (fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up")) + drvdata->skip_power_up = true; + /* Validity for the resource is already checked by the AMBA core */ base = devm_ioremap_resource(dev, res); if (IS_ERR(base)) diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h index 4a695bf90582..72c9a55e67df 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.h +++ b/drivers/hwtracing/coresight/coresight-etm4x.h @@ -407,6 +407,8 @@ struct etmv4_save_state { * @config: structure holding configuration parameters. * @save_state: State to be preserved across power loss * @state_needs_restore: True when there is context to restore after PM exit + * @skip_power_up: Indicates if an implementation can skip powering up + * the trace unit. */ struct etmv4_drvdata { void __iomem *base; @@ -454,6 +456,7 @@ struct etmv4_drvdata { struct etmv4_config config; struct etmv4_save_state *save_state; bool state_needs_restore; + bool skip_power_up; }; /* Address comparator access types */ -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
WARNING: multiple messages have this Message-ID (diff)
From: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> To: Mathieu Poirier <mathieu.poirier@linaro.org>, Suzuki K Poulose <suzuki.poulose@arm.com>, Mike Leach <mike.leach@linaro.org>, devicetree@vger.kernel.org, Rob Herring <robh+dt@kernel.org> Cc: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>, linux-arm-msm@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org, Stephen Boyd <swboyd@chromium.org>, Tingwei Zhang <tingwei@codeaurora.org>, Leo Yan <leo.yan@linaro.org>, linux-arm-kernel@lists.infradead.org Subject: [PATCHv2 1/2] coresight: etm4x: Add support to skip trace unit power up Date: Fri, 15 May 2020 01:27:55 +0530 [thread overview] Message-ID: <7f2aeb36979ebfef30ea8356e6aa3111a611d6b5.1589485594.git.saiprakash.ranjan@codeaurora.org> (raw) In-Reply-To: <cover.1589485594.git.saiprakash.ranjan@codeaurora.org> From: Tingwei Zhang <tingwei@codeaurora.org> On some Qualcomm Technologies Inc. SoCs like SC7180, there exists a hardware errata where the APSS (Application Processor SubSystem)/CPU watchdog counter is stopped when the trace unit power up ETM register is set (TRCPDCR.PU = 1). Since the ETMs share the same power domain as that of respective CPU cores, they are powered on when the CPU core is powered on. So we can skip powering up of trace unit after checking for this errata via new property called "qcom,skip-power-up". Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org> Co-developed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> --- drivers/hwtracing/coresight/coresight-etm4x.c | 27 ++++++++++++------- drivers/hwtracing/coresight/coresight-etm4x.h | 3 +++ 2 files changed, 20 insertions(+), 10 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index fb0f5f4f3a91..b38214326fa4 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -196,12 +196,14 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata) writel_relaxed(config->vmid_mask0, drvdata->base + TRCVMIDCCTLR0); writel_relaxed(config->vmid_mask1, drvdata->base + TRCVMIDCCTLR1); - /* - * Request to keep the trace unit powered and also - * emulation of powerdown - */ - writel_relaxed(readl_relaxed(drvdata->base + TRCPDCR) | TRCPDCR_PU, - drvdata->base + TRCPDCR); + if (!drvdata->skip_power_up) { + /* + * Request to keep the trace unit powered and also + * emulation of powerdown + */ + writel_relaxed(readl_relaxed(drvdata->base + TRCPDCR) | TRCPDCR_PU, + drvdata->base + TRCPDCR); + } /* Enable the trace unit */ writel_relaxed(1, drvdata->base + TRCPRGCTLR); @@ -476,10 +478,12 @@ static void etm4_disable_hw(void *info) CS_UNLOCK(drvdata->base); - /* power can be removed from the trace unit now */ - control = readl_relaxed(drvdata->base + TRCPDCR); - control &= ~TRCPDCR_PU; - writel_relaxed(control, drvdata->base + TRCPDCR); + if (!drvdata->skip_power_up) { + /* power can be removed from the trace unit now */ + control = readl_relaxed(drvdata->base + TRCPDCR); + control &= ~TRCPDCR_PU; + writel_relaxed(control, drvdata->base + TRCPDCR); + } control = readl_relaxed(drvdata->base + TRCPRGCTLR); @@ -1429,6 +1433,9 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) return -ENOMEM; } + if (fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up")) + drvdata->skip_power_up = true; + /* Validity for the resource is already checked by the AMBA core */ base = devm_ioremap_resource(dev, res); if (IS_ERR(base)) diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h index 4a695bf90582..72c9a55e67df 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.h +++ b/drivers/hwtracing/coresight/coresight-etm4x.h @@ -407,6 +407,8 @@ struct etmv4_save_state { * @config: structure holding configuration parameters. * @save_state: State to be preserved across power loss * @state_needs_restore: True when there is context to restore after PM exit + * @skip_power_up: Indicates if an implementation can skip powering up + * the trace unit. */ struct etmv4_drvdata { void __iomem *base; @@ -454,6 +456,7 @@ struct etmv4_drvdata { struct etmv4_config config; struct etmv4_save_state *save_state; bool state_needs_restore; + bool skip_power_up; }; /* Address comparator access types */ -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-05-14 19:58 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-05-14 19:57 [PATCHv2 0/2] coresight: etm4x: Add support to skip trace unit power up Sai Prakash Ranjan 2020-05-14 19:57 ` Sai Prakash Ranjan 2020-05-14 19:57 ` Sai Prakash Ranjan [this message] 2020-05-14 19:57 ` [PATCHv2 1/2] " Sai Prakash Ranjan 2020-05-14 19:57 ` [PATCHv2 2/2] dt-bindings: arm: coresight: " Sai Prakash Ranjan 2020-05-14 19:57 ` Sai Prakash Ranjan
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