Solved
What Device Tree/Configuration of USART/UART does the MP2xROMtracesdump have?
I have built a custom board by using STM32MP257F and I want to boot on USART6.
I have not succeed to boot on USART6 when I compile my own fsbla by change the device tree of TF-A.
I got a suggestion from ST Dev team to run this ROM tracedump wiki-stm32mp-addons/MP2RomTracesDump at 6.1.0 · STMicroelectronics/wiki-stm32mp-addons · GitHub and it gave me a positive output on USART6.
The soldering was OK. The BootROM was OK and the UART6 was alive. This is the output from my USART6.
===================================================
== STM32MP25 cut2.x bootrom display traces V1.01 ==
== Date of compilation : Jun 26 2024 - 11:25:23 ==
===================================================
Executed on Cortex A35 - Aarch64
Successfully booted on interface SD instance 1
Reset reason : POR reset
Chip state : CLOSED_UNLOCKED
==================================================================
Bootrom traces
==================================================================
[INFO] - BOOTCORE_FreezeIWDG12Clocks >
[INFO] - BOOTCORE_HwResetPOR >
[INFO] - BOOTCORE_VarLastValidAppRstMask ( 0x00000015 ) >
[INFO] - BOOTCORE_VarLastValidCpu1RstMask ( 0x00000003 ) >
[INFO] - BOOTCORE_VarLastValidPwrResetSource ( 0x00000000 ) >
[INFO] - BOOTCORE_ValRegHwRstSclrr ( 0x00000000 ) >
[INFO] - BOOTCORE_ValRegC1HwRstSclrr ( 0x00000000 ) >
[INFO] - BOOTCORE_ValRegC1BootRstSclrr ( 0x00002035 ) >
[INFO] - BOOTCORE_ChipModeClosedUnlocked >
[INFO] - BOOTCORE_LogicalResetSystem >
[INFO] - BOOTCORE_BootActionSecureBootProcess >
[INFO] - BOOTCORE_BootPinsSrcSel ( 0x00000001 ) >
[INFO] - BOOTCORE_BootCfgOtpWordValue ( 0x00000000, 0x00000000, 0x00000000 ) >
[INFO] - BOOTCORE_OtpBootpinLayoutSrc ( 0x00000000 ) >
[INFO] - BOOTCORE_OtpSrcSel ( 0x00000000 ) >
[INFO] - BOOTCORE_BootSrcIndexByBootPins ( 0x00000001 ) >
[INFO] - BOOTCORE_BootSrcIndex ( 0x00000001 ) >
[INFO] - BOOTCORE_SRCSEL_A35_SDCARD_SDMMC1_SDCARD_SDMMC1 >
[INFO] - BOOTCORE_OtpBootSrcDisableMaskVal ( 0x00000000 ) >
[INFO] - BOOTCORE_OtpBootUartInstanceDisableMaskVal ( 0x00000000 ) >
[INFO] - CSPID_CSPDEVICE ( 0x00000003 ) >
[INFO] - BOOTCORE_BootCfgAfmuxOtpWord1Value ( 0x00000000 ) >
[INFO] - BOOTCORE_BootCfgAfmuxOtpWord2Value ( 0x00000000 ) >
[INFO] - BOOTCORE_BootCfgAfmuxOtpWord3Value ( 0x00000000 ) >
[INFO] - BOOTCORE_BootCfgHseValue ( 0x00000000 ) >
[INFO] - BOOTCORE_EnabledSrcMaskVal ( 0x00000688 ) >
[INFO] - BOOTCORE_BootCfgHseValue ( 0x00000000 ) >
[INFO] - BOOTCORE_WDGStartAndUnfreeze >
[INFO] - BOOTCORE_UnFreezeIWDG12Clocks >
[INFO] - BOOTCORE_BootModeSECUREBOOT >
[INFO] - BOOTCORE_SecureBootLoadFsblA >
[INFO] - BOOTCORE_StartupWaitTime >
[INFO] - BOOTCORE_Pll14StartBegin >
[INFO] - BOOTCORE_NoCpuPllOtpBitValue ( 0x00000000 ) >
[INFO] - BOOTCORE_Pll1Locked >
[INFO] - BOOTCORE_CkMpuSwitchedOnPll1 >
[INFO] - BOOTCORE_Pll4Locked >
[INFO] - BOOTCORE_CkAxiSwitchedOnPll4 >
[INFO] - FLASHBOOT_HandleInit ( 0x00000003 ) >
[INFO] - SD_CardDetected >
[INFO] - SD_HighCapacityCardSDHCOrSDXC >
[INFO] - SD_TryFSBL1 >
[INFO] - SD_GPTFound >
[INFO] - SD_FsblsFound ( 0x00004400, 0x00044400 ) >
[INFO] - DWNLDMGR_FoundPaddingHeader >
[INFO] - SECBOOTCUSTOM_EnableDataCache >
[INFO] - SECBOOT_AuthenticationExtensionHeaderMissing >
[INFO] - SECBOOT_AuthImageLength ( 0x0000E400 ) >
[INFO] - SECBOOT_AuthImageEntryPoint ( 0x0E002600 ) >
[INFO] - SECBOOT_AuthDecisionIsJumpToImage >
[INFO] - SECBOOTCUSTOM_DisableDataCache >
[INFO] - BOOTCORE_AARCH64BootReq >
==================================================================Question:
I'm planning to use USART6 as early debugging but I need to know what settings the ROMtracedump had for displaying and using USART6.
My Device Tree for TF-A have this following setting. But still, this won't work. I don't know why it won't work. Perhaps if I could know the settings fom the ROMtracedump, then I could understand why the USART6 is working as early debugging and not for my Device Tree for TF-A.
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
/*
* Copyright (C) 2026, STMicroelectronics - All Rights Reserved
* Author: STM32CubeMX code generation for STMicroelectronics.
*/
/* For more information on Device Tree configuration, please refer to
* https://wiki.st.com/stm32mpu/wiki/Category:Device_tree_configuration
*/
/dts-v1/;
#include <dt-bindings/pinctrl/stm32-pinfunc.h>
#include <dt-bindings/clock/stm32mp25-clksrc.h>
*#include "stm32mp25-mx.dtsi"*
#include "stm32mp257.dtsi"
#include "stm32mp25xf.dtsi"
#include "stm32mp257f-firmware-mx-rcc.dtsi"
#include "stm32mp25xxak-pinctrl.dtsi"
#include "stm32mp25-ddr.dtsi"
/* USER CODE BEGIN includes */
/* USER CODE END includes */
/ {
model = "STMicroelectronics custom STM32CubeMX board - openstlinux-6.6-yocto-scarthgap-mpu-v25.06.11";
compatible = "st,stm32mp257f-firmware-mx", "st,stm32mp257";
memory@80000000 {
device_type = "memory";
reg = <0x0 0x80000000 0x00000001 0x00000000>;
/* USER CODE BEGIN memory */
/* USER CODE END memory */
};
/* USER CODE BEGIN root */
aliases{
serial0 = &usart6;
};
chosen{
stdout-path = "serial0:115200n8";
};
clocks {
clk_hse: clk-hse {
#clock-cells = <0>;
compatible = "fixed-clock";
clock-frequency = <24000000>;
};
};
/* USER CODE END root */
}; /*root*/
&pinctrl {
i2c7_pins_mx: i2c7_mx-0 {
pins {
pinmux = <STM32_PINMUX('D', 14, AF10)>, /* I2C7_SDA */
<STM32_PINMUX('D', 15, AF10)>; /* I2C7_SCL */
bias-disable;
drive-open-drain;
slew-rate = <0>;
};
};
sdmmc1_pins_mx: sdmmc1_mx-0 {
pins1 {
pinmux = <STM32_PINMUX('E', 0, AF10)>, /* SDMMC1_D2 */
<STM32_PINMUX('E', 1, AF10)>, /* SDMMC1_D3 */
<STM32_PINMUX('E', 2, AF10)>, /* SDMMC1_CMD */
<STM32_PINMUX('E', 4, AF10)>, /* SDMMC1_D0 */
<STM32_PINMUX('E', 5, AF10)>; /* SDMMC1_D1 */
bias-disable;
drive-push-pull;
slew-rate = <1>;
};
pins2 {
pinmux = <STM32_PINMUX('E', 3, AF10)>; /* SDMMC1_CK */
bias-disable;
drive-push-pull;
slew-rate = <3>;
};
};
usart6_pins_mx: usart6_mx-0 {
pins1 {
pinmux = <STM32_PINMUX('F', 13, AF3)>; /* USART6_TX */
bias-disable;
drive-push-pull;
slew-rate = <0>;
};
pins2 {
pinmux = <STM32_PINMUX('F', 14, AF3)>; /* USART6_RX */
bias-disable;
drive-push-pull;
};
};
/* USER CODE BEGIN pinctrl */
/* USER CODE END pinctrl */
};
&pinctrl_z {
/* USER CODE BEGIN pinctrl_z */
/* USER CODE END pinctrl_z */
};
&bsec {
status = "okay";
/* USER CODE BEGIN bsec */
board_id: board_id@3d8 {
reg = <0x3d8 0x4>;
};
/* USER CODE END bsec */
};
&ddr {
status = "okay";
/* USER CODE BEGIN ddr */
vdd1-supply = <&vdd1_ddr>;
vdd2-supply = <&vdd2_ddr>;
vddq-supply = <&vdd2_ddr>;
/* USER CODE END ddr */
};
&hash {
status = "disable";
/* USER CODE BEGIN hash */
/* USER CODE END hash */
};
&i2c7 {
pinctrl-names = "default";
pinctrl-0 = <&i2c7_pins_mx>;
status = "okay";
/* USER CODE BEGIN i2c7 */
i2c-scl-rising-time-ns = <185>;
i2c-scl-falling-time-ns = <20>;
clock-frequency = <400000>;
#address-cells = <1>;
#size-cells = <0>;
pmic2: stpmic@33 {
compatible = "st,stpmic2";
reg = <0x33>;
status = "okay";
regulators {
compatible = "st,stpmic2-regulators";
vddcpu: buck1 {
regulator-name = "vddcpu";
regulator-min-microvolt = <800000>;
regulator-max-microvolt = <910000>;
regulator-always-on;
};
vddcore: buck2 {
regulator-name = "vddcore";
regulator-min-microvolt = <820000>;
regulator-max-microvolt = <820000>;
regulator-always-on;
};
vddgpu: buck3 {
regulator-name = "vddgpu";
regulator-min-microvolt = <800000>;
regulator-max-microvolt = <900000>;
regulator-always-on;
};
vddio_pmic: buck4 {
regulator-name = "vddio_pmic";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
};
v1v8: buck5 {
regulator-name = "v1v8";
regulator-min-microvolt = <1800000>;
regulator-max-microvolt = <1800000>;
regulator-always-on;
};
vdd2_ddr: buck6 {
regulator-name = "vdd2_ddr";
regulator-min-microvolt = <1100000>;
regulator-max-microvolt = <1100000>;
};
v3v3: buck7 {
regulator-name = "v3v3";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
};
vdda1v8_aon: ldo1 {
regulator-name = "vdda1v8_aon";
regulator-min-microvolt = <1800000>;
regulator-max-microvolt = <1800000>;
regulator-always-on;
};
vdd_emmc: ldo2 {
regulator-name = "vdd_SD_card_temporary";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
};
vdd1_ddr: ldo3 {
regulator-name = "vdd1_ddr";
regulator-min-microvolt = <1800000>;
regulator-max-microvolt = <1800000>;
};
vdd3v3_usb: ldo4 {
regulator-name = "vdd3v3_usb";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
};
v5v_hdmi: ldo5 {
regulator-name = "v5v_hdmi";
regulator-min-microvolt = <2000000>;
regulator-max-microvolt = <2000000>;
};
vdd_sdcard: ldo7 {
regulator-name = "vdd_sdcard";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
};
vddio_sdcard: ldo8 {
regulator-name = "vddio_sdcard";
st,regulator-bypass-microvolt = <3300000>;
regulator-min-microvolt = <1800000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
};
};
};
/* USER CODE END i2c7 */
};
&iwdg1 {
status = "disable";
/* USER CODE BEGIN iwdg1 */
timeout-sec = <32>;
/* USER CODE END iwdg1 */
};
&pka {
status = "disable";
/* USER CODE BEGIN pka */
/* USER CODE END pka */
};
&rcc {
status = "okay";
/* USER CODE BEGIN rcc */
/* USER CODE END rcc */
};
&rng {
status = "disable";
/* USER CODE BEGIN rng */
/* USER CODE END rng */
};
&saes {
status = "disable";
/* USER CODE BEGIN saes */
/* USER CODE END saes */
};
&sdmmc1 {
pinctrl-names = "default";
pinctrl-0 = <&sdmmc1_pins_mx>;
status = "okay";
/* USER CODE BEGIN sdmmc1 */
st,neg-edge;
bus-width = <4>;
vmmc-supply = <&vdd_sdcard>;
vqmmc-supply = <&vddio1>;
/delete-property/ cap-sd-highspeed;
/delete-property/ cap-mmc-highspeed;
/* USER CODE END sdmmc1 */
};
&usart6 {
pinctrl-names = "default";
pinctrl-0 = <&usart6_pins_mx>;
status = "okay";
/* USER CODE BEGIN usart6 */
/* USER CODE END usart6 */
};
/* USER CODE BEGIN addons */
/* USER CODE END addons */