The DDR is configured for LPDDR4 running at 1.6GHz which requires the voltage on the PMIC to rise a bit before initializing LPDDR4 or it will be running out of spec.
Signed-off-by: Adam Ford aford173@gmail.com
diff --git a/board/beacon/imx8mn/spl.c b/board/beacon/imx8mn/spl.c index 029f71bc99..9acd916180 100644 --- a/board/beacon/imx8mn/spl.c +++ b/board/beacon/imx8mn/spl.c @@ -74,6 +74,38 @@ static iomux_v3_cfg_t const pwm_pads[] = { IMX8MN_PAD_GPIO1_IO01__PWM1_OUT | MUX_PAD_CTRL(PWM1_PAD_CTRL), };
+static int power_init_board(void) +{ + struct udevice *dev; + int ret; + + ret = pmic_get("pmic@4b", &dev); + if (ret == -ENODEV) { + puts("No pmic\n"); + return 0; + } + + if (ret != 0) + return ret; + + /* decrease RESET key long push time from the default 10s to 10ms */ + pmic_reg_write(dev, BD718XX_PWRONCONFIG1, 0x0); + + /* unlock the PMIC regs */ + pmic_reg_write(dev, BD718XX_REGLOCK, 0x1); + + /* increase VDD_SOC to typical value 0.85v before first DRAM access */ + pmic_reg_write(dev, BD718XX_BUCK1_VOLT_RUN, 0x0f); + + /* increase VDD_DRAM to 0.975v for 3Ghz DDR */ + pmic_reg_write(dev, BD718XX_1ST_NODVS_BUCK_VOLT, 0x83); + + /* lock the PMIC regs */ + pmic_reg_write(dev, BD718XX_REGLOCK, 0x11); + + return 0; +} + int board_early_init_f(void) { /* Claiming pwm pins prevents LCD flicker during startup*/ @@ -107,6 +139,9 @@ void board_init_f(ulong dummy)
enable_tzc380();
+ /* LPDDR4 at 1.6GHz requires a voltage adjustment on the PMIC */ + power_init_board(); + /* DDR initialization */ spl_dram_init();