ENGR00279402-2 ARM: imx6q: imx6sl: System reset by checking the source setting

Check the source setting in dts file to support different WDOG reset event.
Correct imx6sl_restart instead of mxc_restart.

Signed-off-by: Robin Gong <b38343@freescale.com>

2 files changed, 84 insertions, 3 deletions

diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
index e92ee05b98a8..72b4d9fbc5d3 100644
--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c
@@ -45,6 +45,13 @@ static void imx6q_restart(char mode, const char *cmd)
 {
         struct device_node *np;
         void __iomem *wdog_base;
+        u32 wdog_source = 1; /* use WDOG1 default */
+        unsigned int value;
+
+        np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
+        if (np)
+                of_property_read_u32(np, "fsl,wdog-reset", &wdog_source);
+        pr_info("Use WDOG%d as reset source\n", wdog_source);
 
         np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-wdt");
         wdog_base = of_iomap(np, 0);
@@ -53,10 +60,27 @@ static void imx6q_restart(char mode, const char *cmd)
 
         imx_src_prepare_restart();
 
+        if (wdog_source == 2) {
+                /*
+                 * Some boards  use WDOG2 to reset external pmic in bypass mode,
+                 * so do WDOG2 reset here. Do not set SRS,since we will
+                 * trigger external POR later. Use WDOG1 to reset in ldo-enable
+                 * mode.
+                 */
+                np = of_find_compatible_node(np, NULL, "fsl,imx6q-wdt");
+                wdog_base = of_iomap(np, 0);
+                if (!wdog_base) {
+                        pr_warn("Not found wdt2, please check your dts!\n");
+                        goto soft;
+                }
+                value = 0x14;
+        } else {
+                value = (1 << 2);
+        }
         /* enable wdog */
-        writew_relaxed(1 << 2, wdog_base);
+        writew_relaxed(value, wdog_base);
         /* write twice to ensure the request will not get ignored */
-        writew_relaxed(1 << 2, wdog_base);
+        writew_relaxed(value, wdog_base);
 
         /* wait for reset to assert ... */
         mdelay(500);
diff --git a/arch/arm/mach-imx/mach-imx6sl.c b/arch/arm/mach-imx/mach-imx6sl.c
index e1c83798bc3d..4265f1105b51 100644
--- a/arch/arm/mach-imx/mach-imx6sl.c
+++ b/arch/arm/mach-imx/mach-imx6sl.c
@@ -8,8 +8,10 @@
  */
 
 #include <linux/clk-provider.h>
+#include <linux/delay.h>
 #include <linux/irqchip.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/opp.h>
 #include <linux/regmap.h>
@@ -17,6 +19,7 @@
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
+#include <asm/system_misc.h>
 
 #include "common.h"
 #include "cpuidle.h"
@@ -26,6 +29,60 @@ static struct platform_device imx6sl_cpufreq_pdev = {
         .name = "imx6-cpufreq",
 };
 
+static void imx6sl_restart(char mode, const char *cmd)
+{
+        struct device_node *np;
+        void __iomem *wdog_base;
+        u32 wdog_source = 1; /* use WDOG1 default */
+        unsigned int value;
+
+        np = of_find_compatible_node(NULL, NULL, "fsl,imx6sl-gpc");
+        if (np)
+                of_property_read_u32(np, "fsl,wdog-reset", &wdog_source);
+        pr_info("Use WDOG%d as reset source\n", wdog_source);
+
+        np = of_find_compatible_node(NULL, NULL, "fsl,imx6sl-wdt");
+        wdog_base = of_iomap(np, 0);
+        if (!wdog_base)
+                goto soft;
+
+        imx_src_prepare_restart();
+
+        if (wdog_source == 2) {
+                /*
+                 * Some boards  use WDOG2 to reset external pmic in bypass mode,
+                 * so do WDOG2 reset here. Do not set SRS,since we will
+                 * trigger external POR later. Use WDOG1 to reset in ldo-enable
+                 * mode. You can set it by "fsl,wodog-reset" in dts.
+                 */
+                np = of_find_compatible_node(np, NULL, "fsl,imx6sl-wdt");
+                wdog_base = of_iomap(np, 0);
+                if (!wdog_base) {
+                        pr_warn("Not found wdt2, please check your dts!\n");
+                        goto soft;
+                }
+                value = 0x14;
+        } else {
+                value = (1 << 2);
+        }
+        /* enable wdog */
+        writew_relaxed(value, wdog_base);
+        /* write twice to ensure the request will not get ignored */
+        writew_relaxed(value, wdog_base);
+
+        /* wait for reset to assert ... */
+        mdelay(500);
+
+        pr_err("Watchdog reset failed to assert reset\n");
+
+        /* delay to allow the serial port to show the message */
+        mdelay(50);
+
+soft:
+        /* we'll take a jump through zero as a poor second */
+        soft_restart(0);
+}
+
 static void __init imx6sl_fec_init(void)
 {
         struct regmap *gpr;
@@ -137,5 +194,5 @@ DT_MACHINE_START(IMX6SL, "Freescale i.MX6 SoloLite (Device Tree)")
         .init_machine   = imx6sl_init_machine,
         .init_late      = imx6sl_init_late,
         .dt_compat      = imx6sl_dt_compat,
-        .restart        = mxc_restart,
+        .restart        = imx6sl_restart,
 MACHINE_END