diff options
| author | Aurelien Jarno <aurelien@aurel32.net> | 2022-01-04 23:01:54 +0100 |
|---|---|---|
| committer | Aurelien Jarno <aurelien@aurel32.net> | 2022-01-05 08:18:15 +0100 |
| commit | 6313f92ea1bba27c4716523c849593384f309aa1 (patch) | |
| tree | 40ab57ce06e79a8ac4ea077b12b0f30464ecd5be | |
| parent | 4745498570ef46fdb43acf40ce4e7dd4c05a7322 (diff) | |
platform: sifive_fu740: fix reset when watchdog is runningfu740-reset-wdt
When the watchdog is running the HiFive Unmatched board does not reboot
properly and shuts down itself a few seconds after reboot, in the early
stages of the u-boot loading. On a Linux kernel this happens when the
da9063_wdt module is loaded. This does not happen if the module is
unloaded before reboot or if the watchdog module is loaded with
"stop_on_reboot=1".
Fix that by stopping the watchdog before attempting to reset the board.
This is done by zeroing the TWDSCALE field of CONTROL_D register, unless
it was already set to 0.
Reported-by: Tianon Gravi <tianon@debian.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
| -rw-r--r-- | platform/generic/sifive_fu740.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/platform/generic/sifive_fu740.c b/platform/generic/sifive_fu740.c index 866e924..f595c04 100644 --- a/platform/generic/sifive_fu740.c +++ b/platform/generic/sifive_fu740.c @@ -22,6 +22,7 @@ #define DA9063_REG_PAGE_CON 0x00 #define DA9063_REG_CONTROL_A 0x0e +#define DA9063_REG_CONTROL_D 0x11 #define DA9063_REG_CONTROL_F 0x13 #define DA9063_REG_DEVICE_ID 0x81 @@ -29,6 +30,8 @@ #define DA9063_CONTROL_A_M_POWER_EN (1 << 5) #define DA9063_CONTROL_A_STANDBY (1 << 3) +#define DA9063_CONTROL_D_TWDSCALE_MASK 0x07 + #define DA9063_CONTROL_F_WAKEUP (1 << 2) #define DA9063_CONTROL_F_SHUTDOWN (1 << 1) @@ -79,6 +82,27 @@ static inline int da9063_sanity_check(struct i2c_adapter *adap, uint32_t reg) return 0; } +static inline int da9063_stop_watchdog(struct i2c_adapter *adap, uint32_t reg) +{ + uint8_t val; + int rc = i2c_adapter_reg_write(adap, reg, + DA9063_REG_PAGE_CON, 0x00); + + if (rc) + return rc; + + rc = i2c_adapter_reg_read(adap, reg, DA9063_REG_CONTROL_D, &val); + if (rc) + return rc; + + if ((val & DA9063_CONTROL_D_TWDSCALE_MASK) == 0) + return 0; + + val &= ~DA9063_CONTROL_D_TWDSCALE_MASK; + + return i2c_adapter_reg_write(adap, reg, DA9063_REG_CONTROL_D, val); +} + static inline int da9063_shutdown(struct i2c_adapter *adap, uint32_t reg) { int rc = i2c_adapter_reg_write(adap, reg, @@ -133,6 +157,7 @@ static void da9063_system_reset(u32 type, u32 reason) break; case SBI_SRST_RESET_TYPE_COLD_REBOOT: case SBI_SRST_RESET_TYPE_WARM_REBOOT: + da9063_stop_watchdog(adap, reg); da9063_reset(adap, reg); break; } |