1 files changed, 56 insertions, 2 deletions

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index e91e59ecec53..43f583987250 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -30,6 +30,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/property.h>
+#include <linux/clk/clk-conf.h>
 
 #include <asm/barrier.h>
 #include <asm/sections.h>
@@ -1073,11 +1074,21 @@ static bool etm4_init_sysreg_access(struct etmv4_drvdata *drvdata,
 	return true;
 }
 
+static bool is_devtype_cpu_trace(void __iomem *base)
+{
+	u32 devtype = readl(base + TRCDEVTYPE);
+
+	return (devtype == CS_DEVTYPE_PE_TRACE);
+}
+
 static bool etm4_init_iomem_access(struct etmv4_drvdata *drvdata,
 				   struct csdev_access *csa)
 {
 	u32 devarch = readl_relaxed(drvdata->base + TRCDEVARCH);
 
+	if (!is_coresight_device(drvdata->base) || !is_devtype_cpu_trace(drvdata->base))
+		return false;
+
 	/*
 	 * All ETMs must implement TRCDEVARCH to indicate that
 	 * the component is an ETMv4. Even though TRCIDR1 also
@@ -2135,6 +2146,7 @@ static int etm4_probe_amba(struct amba_device *adev, const struct amba_id *id)
 
 static int etm4_probe_platform_dev(struct platform_device *pdev)
 {
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	struct etmv4_drvdata *drvdata;
 	int ret;
 
@@ -2142,7 +2154,18 @@ static int etm4_probe_platform_dev(struct platform_device *pdev)
 	if (!drvdata)
 		return -ENOMEM;
 
-	drvdata->base = NULL;
+	drvdata->pclk = coresight_get_enable_apb_pclk(&pdev->dev);
+	if (IS_ERR(drvdata->pclk))
+		return -ENODEV;
+
+	if (res) {
+		drvdata->base = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(drvdata->base)) {
+			clk_put(drvdata->pclk);
+			return PTR_ERR(drvdata->base);
+		}
+	}
+
 	dev_set_drvdata(&pdev->dev, drvdata);
 	pm_runtime_get_noresume(&pdev->dev);
 	pm_runtime_set_active(&pdev->dev);
@@ -2188,7 +2211,7 @@ static struct amba_cs_uci_id uci_id_etm4[] = {
 		/*  ETMv4 UCI data */
 		.devarch	= ETM_DEVARCH_ETMv4x_ARCH,
 		.devarch_mask	= ETM_DEVARCH_ID_MASK,
-		.devtype	= 0x00000013,
+		.devtype	= CS_DEVTYPE_PE_TRACE,
 	}
 };
 
@@ -2244,6 +2267,10 @@ static int __exit etm4_remove_platform_dev(struct platform_device *pdev)
 	if (drvdata)
 		etm4_remove_dev(drvdata);
 	pm_runtime_disable(&pdev->dev);
+
+	if (drvdata->pclk)
+		clk_put(drvdata->pclk);
+
 	return 0;
 }
 
@@ -2288,6 +2315,32 @@ static struct amba_driver etm4x_amba_driver = {
 	.id_table	= etm4_ids,
 };
 
+#ifdef CONFIG_PM
+static int etm4_runtime_suspend(struct device *dev)
+{
+	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev);
+
+	if (drvdata->pclk && !IS_ERR(drvdata->pclk))
+		clk_disable_unprepare(drvdata->pclk);
+
+	return 0;
+}
+
+static int etm4_runtime_resume(struct device *dev)
+{
+	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev);
+
+	if (drvdata->pclk && !IS_ERR(drvdata->pclk))
+		clk_prepare_enable(drvdata->pclk);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops etm4_dev_pm_ops = {
+	SET_RUNTIME_PM_OPS(etm4_runtime_suspend, etm4_runtime_resume, NULL)
+};
+
 static const struct of_device_id etm4_sysreg_match[] = {
 	{ .compatible	= "arm,coresight-etm4x-sysreg" },
 	{ .compatible	= "arm,embedded-trace-extension" },
@@ -2301,6 +2354,7 @@ static struct platform_driver etm4_platform_driver = {
 		.name			= "coresight-etm4x",
 		.of_match_table		= etm4_sysreg_match,
 		.suppress_bind_attrs	= true,
+		.pm			= &etm4_dev_pm_ops,
 	},
 };