lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Tue,  9 Jan 2024 19:45:21 +0800
From: tianyu2 <tianyu2@...nelsoft.com>
To: rafael@...nel.org,
	viresh.kumar@...aro.org,
	shawnguo@...nel.org,
	s.hauer@...gutronix.de
Cc: kernel@...gutronix.de,
	festevam@...il.com,
	linux-imx@....com,
	linux-pm@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] cpufreq: imx6: use regmap to read ocotp register

Reading the ocotp register directly is unsafe and will cause the system
to hang if its clock is not turned on in CCM. The regmap interface has
clk enabled, which can solve this problem.

Signed-off-by: tianyu2 <tianyu2@...nelsoft.com>
---
 drivers/cpufreq/imx6q-cpufreq.c | 45 +++++++++++----------------------
 1 file changed, 15 insertions(+), 30 deletions(-)

diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c
index 494d044b9e72..f18b9ee5e484 100644
--- a/drivers/cpufreq/imx6q-cpufreq.c
+++ b/drivers/cpufreq/imx6q-cpufreq.c
@@ -14,6 +14,8 @@
 #include <linux/pm_opp.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/consumer.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
 
 #define PU_SOC_VOLTAGE_NORMAL	1250000
 #define PU_SOC_VOLTAGE_HIGH	1275000
@@ -225,8 +227,6 @@ static void imx6x_disable_freq_in_opp(struct device *dev, unsigned long freq)
 
 static int imx6q_opp_check_speed_grading(struct device *dev)
 {
-	struct device_node *np;
-	void __iomem *base;
 	u32 val;
 	int ret;
 
@@ -235,16 +235,11 @@ static int imx6q_opp_check_speed_grading(struct device *dev)
 		if (ret)
 			return ret;
 	} else {
-		np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-ocotp");
-		if (!np)
-			return -ENOENT;
+		struct regmap *ocotp;
 
-		base = of_iomap(np, 0);
-		of_node_put(np);
-		if (!base) {
-			dev_err(dev, "failed to map ocotp\n");
-			return -EFAULT;
-		}
+		ocotp = syscon_regmap_lookup_by_compatible("fsl,imx6q-ocotp");
+		if (IS_ERR(ocotp))
+			return -ENOENT;
 
 		/*
 		 * SPEED_GRADING[1:0] defines the max speed of ARM:
@@ -254,8 +249,7 @@ static int imx6q_opp_check_speed_grading(struct device *dev)
 		 * 2b'00: 792000000Hz;
 		 * We need to set the max speed of ARM according to fuse map.
 		 */
-		val = readl_relaxed(base + OCOTP_CFG3);
-		iounmap(base);
+		regmap_read(ocotp, OCOTP_CFG3, &val);
 	}
 
 	val >>= OCOTP_CFG3_SPEED_SHIFT;
@@ -290,25 +284,16 @@ static int imx6ul_opp_check_speed_grading(struct device *dev)
 		if (ret)
 			return ret;
 	} else {
-		struct device_node *np;
-		void __iomem *base;
-
-		np = of_find_compatible_node(NULL, NULL, "fsl,imx6ul-ocotp");
-		if (!np)
-			np = of_find_compatible_node(NULL, NULL,
-						     "fsl,imx6ull-ocotp");
-		if (!np)
-			return -ENOENT;
+		struct regmap *ocotp;
 
-		base = of_iomap(np, 0);
-		of_node_put(np);
-		if (!base) {
-			dev_err(dev, "failed to map ocotp\n");
-			return -EFAULT;
-		}
+		ocotp = syscon_regmap_lookup_by_compatible("fsl,imx6ul-ocotp");
+		if (IS_ERR(ocotp))
+			ocotp = syscon_regmap_lookup_by_compatible("fsl,imx6ull-ocotp");
+
+		if (IS_ERR(ocotp))
+			return -ENOENT;
 
-		val = readl_relaxed(base + OCOTP_CFG3);
-		iounmap(base);
+		regmap_read(ocotp, OCOTP_CFG3, &val);
 	}
 
 	/*
-- 
2.25.1


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ