[MA35D1] 如何控制让M4自己重启而不影响A35

如何控制让M4自己重启而不影响A35

我们有3个watchdog，wdt0不用配置，默认给A35，wdt1和wdt2可以配置，配置寄存器是SYS_MISCRFCR（SYS_BA+0x014）

bit18：

WDT 1 Reset Real Time Cortex-M4 Sub-system Enable Bit (Write Protect)

0 = WDT 1 reset real time Cortex-M4 sub-system Disabled. (Default)

1 = WDT 1 reset real time Cortex-M4 sub-system Enabled.

Note 1: This bit is write protected. Refer to the SYS_RLKTZS register.

Note 2: This bit keeps high if WDT1ON (SYS_PWRONOTP) is high. 

bit17：

WDT 2 Reset Cortex-A35 Enable Bit (Write Protect)

0 = WDT 2 reset Cortex-A35 Disabled. (Default)

1 = WDT 2 reset Cortex-A35 Enabled.

Note: This bit is write protected. Refer to the SYS_RLKTZS register. 

bit16:

WDT 1 Reset Cortex-A35 Enable Bit (Write Protect)

0 = WDT 1 reset Cortex-A35 Disabled. (Default)

1 = WDT 1 reset Cortex-A35 Enabled.

Note 1: This bit is write protected. Refer to the SYS_RLKTZS register.

Note 2: This bit keeps high if WDT1ON (SYS_PWRONOTP) is high.

平台默认配置是0x70000，也就是这3个bit都设置为1，这2个wdt 都会使A35和M4重启。

如果需要M4重启而A35不重启，那么需要修改这个值。

修改位置：

arm-trusted-firmware-custom/plat/nuvoton/ma35d1/ma35d1_common.c

        /* enable WDT1/WDT2 reset */

        outp32((void *)(SYS_BA+0x14), 0x70000);

修改为

        /* enable WDT1/WDT2 reset */

        outp32((void *)(SYS_BA+0x14), 0x50000);