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| author | Fabio Estevam <fabio.estevam@freescale.com> | 2013-02-07 06:45:23 +0000 |
|---|---|---|
| committer | Stefano Babic <sbabic@denx.de> | 2013-02-12 13:54:34 +0100 |
| commit | 76c91e668a54a45fa06086d4044fcae0b6ce225a (patch) | |
| tree | d67aadea25803bfb73fad2aded5ad09e30302715 /arch | |
| parent | 7c92c540754a0c3756d467a9b0695f2a40d1fe86 (diff) | |
| download | u-boot-imx-76c91e668a54a45fa06086d4044fcae0b6ce225a.zip u-boot-imx-76c91e668a54a45fa06086d4044fcae0b6ce225a.tar.gz u-boot-imx-76c91e668a54a45fa06086d4044fcae0b6ce225a.tar.bz2 | |
mx6: Disable Power Down Bit of watchdog
On a mx6qsabresd revision C board with rev1.2 mx6q, the system gets resetted
and it is not able to reach the Linux prompt.
Comparing the watchdog behaviour on a revB versus revC board:
- On a mx6qsabresd revB:
U-Boot > reset
resetting ...
U-Boot 2013.01-10524-g432a3aa-dirty (Feb 07 2013 - 13:34:46)
CPU: Freescale i.MX6Q rev1.1 at 792 MHz
Reset cause: WDOG
...
- On a mx6qsabresd revC:
U-Boot > reset
resetting ...
U-Boot 2013.01-10524-g432a3aa-dirty (Feb 07 2013 - 13:34:46)
CPU: Freescale i.MX6Q rev1.1 at 792 MHz
Reset cause: POR
So due to revC POR/watchdog circuitry whenever a watchdog occurs, it causes a POR.
Clearing the PDE - Power Down Enable bit of WMCR registers fixes the problem and
is also safe for all mx6 boards.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Otavio Salvador <otavio@ossystems.com.br>
Acked-by: Stefano Babic <sbabic@denx.de>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/cpu/armv7/mx6/soc.c | 12 | ||||
| -rw-r--r-- | arch/arm/include/asm/arch-mx6/imx-regs.h | 8 |
2 files changed, 20 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/mx6/soc.c b/arch/arm/cpu/armv7/mx6/soc.c index a8aad5d..efe4136 100644 --- a/arch/arm/cpu/armv7/mx6/soc.c +++ b/arch/arm/cpu/armv7/mx6/soc.c @@ -30,6 +30,7 @@ #include <asm/arch/clock.h> #include <asm/arch/sys_proto.h> #include <asm/imx-common/boot_mode.h> +#include <stdbool.h> struct scu_regs { u32 ctrl; @@ -121,12 +122,23 @@ void set_vddsoc(u32 mv) writel(reg, &anatop->reg_core); } +static void imx_set_wdog_powerdown(bool enable) +{ + struct wdog_regs *wdog1 = (struct wdog_regs *)WDOG1_BASE_ADDR; + struct wdog_regs *wdog2 = (struct wdog_regs *)WDOG2_BASE_ADDR; + + /* Write to the PDE (Power Down Enable) bit */ + writew(enable, &wdog1->wmcr); + writew(enable, &wdog2->wmcr); +} + int arch_cpu_init(void) { init_aips(); set_vddsoc(1200); /* Set VDDSOC to 1.2V */ + imx_set_wdog_powerdown(false); /* Disable PDE bit of WMCR register */ return 0; } diff --git a/arch/arm/include/asm/arch-mx6/imx-regs.h b/arch/arm/include/asm/arch-mx6/imx-regs.h index 3eb0081..eaa7439 100644 --- a/arch/arm/include/asm/arch-mx6/imx-regs.h +++ b/arch/arm/include/asm/arch-mx6/imx-regs.h @@ -601,5 +601,13 @@ struct iomuxc_base_regs { u32 daisy[104]; /* 0x7b0..94c */ }; +struct wdog_regs { + u16 wcr; /* Control */ + u16 wsr; /* Service */ + u16 wrsr; /* Reset Status */ + u16 wicr; /* Interrupt Control */ + u16 wmcr; /* Miscellaneous Control */ +}; + #endif /* __ASSEMBLER__*/ #endif /* __ASM_ARCH_MX6_IMX_REGS_H__ */ |