diff options
| -rw-r--r-- | src/mainboard/google/gru/bootblock.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/src/mainboard/google/gru/bootblock.c b/src/mainboard/google/gru/bootblock.c index d08b4cba69..74e02b273f 100644 --- a/src/mainboard/google/gru/bootblock.c +++ b/src/mainboard/google/gru/bootblock.c @@ -22,6 +22,19 @@ void bootblock_mainboard_early_init(void) { + /* Let gpio2ab io domains works at 1.8V. + * + * If io_vsel[0] == 0(default value), gpio2ab io domains is 3.0V + * powerd by APIO2_VDD, otherwise, 1.8V supplied by APIO2_VDDPST. + * But from the schematic of kevin rev0, the APIO2_VDD and + * APIO2_VDDPST both are 1.8V(intentionally?). + * + * So, by default, CPU1_SDIO_PWREN(GPIO2_A2) can't output 3.0V + * because the supply is 1.8V. + * Let ask GPIO2_A2 output 1.8V to make GPIO interal logic happy. + */ + write32(&rk3399_grf->io_vsel, RK_SETBITS(1 << 0)); + if (IS_ENABLED(CONFIG_DRIVERS_UART)) { _Static_assert(CONFIG_CONSOLE_SERIAL_UART_ADDRESS == UART2_BASE, "CONSOLE_SERIAL_UART should be UART2"); |