arm: socfpga: Add watchdog disable for socfpga

This adds watchdog disable. It is neccessary for running Linux kernel.

Signed-off-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <clsee@altera.com>
Cc: Dinh Nguyen <dinguyen@altera.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Tom Rini <trini@ti.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Pavel Machek <pavel@denx.de>
V2: Move RSTMGR_PERMODRST_L4WD0_LSB to reset_manager.h
    Reset watchdog only if CONFIG_HW_WATCHDOG is undefined (the default)

diff --git a/arch/arm/cpu/armv7/socfpga/misc.c b/arch/arm/cpu/armv7/socfpga/misc.c
index ecae393410503739c1e8007442ae613a64317095..b633615208f683ee32c85cf4f7f0f68dd58a192a 100644 (file)
--- a/arch/arm/cpu/armv7/socfpga/misc.c
+++ b/arch/arm/cpu/armv7/socfpga/misc.c
@@ -8,6 +8,7 @@
 #include <asm/io.h>
 #include <miiphy.h>
 #include <netdev.h>
+#include <asm/arch/reset_manager.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -36,6 +37,19 @@ int overwrite_console(void)
 }
 #endif
 
+int arch_cpu_init(void)
+{
+       /*
+        * If the HW watchdog is NOT enabled, make sure it is not running,
+        * for example because it was enabled in the preloader. This might
+        * trigger a watchdog-triggered reboot of Linux kernel later.
+        */
+#ifndef CONFIG_HW_WATCHDOG
+       socfpga_watchdog_reset();
+#endif
+       return 0;
+}
+
 int misc_init_r(void)
 {
        return 0;

diff --git a/arch/arm/cpu/armv7/socfpga/reset_manager.c b/arch/arm/cpu/armv7/socfpga/reset_manager.c
index e320c011aef52b411ea0aa03db80aa3bb181a5c2..5d7aba467f70af05e83ceda8cebb945b8a892b1b 100644 (file)
--- a/arch/arm/cpu/armv7/socfpga/reset_manager.c
+++ b/arch/arm/cpu/armv7/socfpga/reset_manager.c
@@ -14,6 +14,18 @@ DECLARE_GLOBAL_DATA_PTR;
 static const struct socfpga_reset_manager *reset_manager_base =
                (void *)SOCFPGA_RSTMGR_ADDRESS;
 
+/* Toggle reset signal to watchdog (WDT is disabled after this operation!) */
+void socfpga_watchdog_reset(void)
+{
+       /* assert reset for watchdog */
+       setbits_le32(&reset_manager_base->per_mod_reset,
+                    1 << RSTMGR_PERMODRST_L4WD0_LSB);
+
+       /* deassert watchdog from reset (watchdog in not running state) */
+       clrbits_le32(&reset_manager_base->per_mod_reset,
+                    1 << RSTMGR_PERMODRST_L4WD0_LSB);
+}
+
 /*
  * Write the reset manager register to cause reset
  */

diff --git a/arch/arm/include/asm/arch-socfpga/reset_manager.h b/arch/arm/include/asm/arch-socfpga/reset_manager.h
index 3e9547682833c25cfd2e5c5c0c48f49c05a570ed..18506e69fd1fd20bad516d19dec3f3d0ee67ad9d 100644 (file)
--- a/arch/arm/include/asm/arch-socfpga/reset_manager.h
+++ b/arch/arm/include/asm/arch-socfpga/reset_manager.h
@@ -10,6 +10,8 @@
 void reset_cpu(ulong addr);
 void reset_deassert_peripherals_handoff(void);
 
+void socfpga_watchdog_reset(void);
+
 struct socfpga_reset_manager {
        u32     status;
        u32     ctrl;
@@ -27,4 +29,6 @@ struct socfpga_reset_manager {
 #define RSTMGR_CTRL_SWWARMRSTREQ_LSB 1
 #endif
 
+#define RSTMGR_PERMODRST_L4WD0_LSB     6
+
 #endif /* _RESET_MANAGER_H_ */