Not able to boot from EMMC on STM32MP157DAC PANIC at PC : 0x2ffec98b

[adnan_pasha]

Hi,

We have a custom carrier board based on STM32MP157DAC. We have built a custom yocto image.

• Yocto Version: Mickledore
• Machine: stm32mp15-disco
• SoM: STM32MP157DAC
• Distro: openstlinux-weston
• Linux Kernel: 6.1.82-stm32mp-r2-r0
• EMMC : EMMC04G-MT32-FBGA153

I was able to flash emmc image in DFU mode (000) after making uboot device tree changes I have done same changes in tfa device tree too. But when trying to boot from EMMC (010) It says SDMMC2 init fails and stops.

NOTICE: CPU: STM32MP157DAC Rev.Z
NOTICE: Model: STMicroelectronics STM32MP157F-DK2 Discovery Board
INFO: PMIC version = 0x21
INFO: Reset reason (0x15):
INFO: Power-on Reset (rst_por)
INFO: FCONF: Reading TB_FW firmware configuration file from: 0x2ffe2000
INFO: FCONF: Reading firmware configuration information for: stm32mp_io
INFO: FCONF: Reading firmware configuration information for: stm32mp_fuse
INFO: Using EMMC
INFO: Instance 2
INFO: Boot used partition fsbl1
ERROR: CMD13 failed after 5 retries
ERROR: SDMMC2 init failed
PANIC at PC : 0x2ffec98b

Thanks.

[adnan_pasha]

Hi,

Below is my device tree configuration Am i missing something or do i need to configure any thing else like clock or something.

&sdmmc2 {
pinctrl-names = "default";
pinctrl-0 = <&sdmmc2_b4_pins_a &sdmmc2_d47_pins_c>;
non-removable;
no-sd;
no-sdio;
st,neg-edge;
bus-width = <8>;
vqmmc-supply = <&vdd>;
mmc-ddr-3_3v;
status = "okay";
};

sdmmc2_b4_pins_a: sdmmc2-b4-0 {
pins1 {
u-boot,dm-pre-reloc;
u-boot,dm-spl;

pinmux = <STM32_PINMUX('B', 14, AF9)>, /* SDMMC2_D0 */
<STM32_PINMUX('B', 15, AF9)>, /* SDMMC2_D1 */
<STM32_PINMUX('B', 3, AF9)>, /* SDMMC2_D2 */
<STM32_PINMUX('B', 4, AF9)>, /* SDMMC2_D3 */
<STM32_PINMUX('G', 6, AF10)>; /* SDMMC2_CMD */
slew-rate = <1>;
drive-push-pull;
bias-pull-up;
};
pins2 {
u-boot,dm-pre-reloc;
u-boot,dm-spl;

pinmux = <STM32_PINMUX('E', 3, AF9)>; /* SDMMC2_CK */
slew-rate = <2>;
drive-push-pull;
bias-pull-up;
};
};
sdmmc2_d47_pins_c: sdmmc2-d47-2 {
pins {
pinmux = <STM32_PINMUX('A', 8, AF9)>, /* SDMMC2_D4 */
<STM32_PINMUX('A', 15, AF9)>, /* SDMMC2_D5 */
<STM32_PINMUX('C', 6, AF10)>, /* SDMMC2_D6 */
<STM32_PINMUX('C', 7, AF10)>; /* SDMMC2_D7 */
slew-rate = <1>;
drive-push-pull;
bias-pull-up;
};
};

Do let me know why this is happening and how we can fix this issue? Do we need to check any voltages in hardware?

Thanks.

[PatrickF]

Hi @adnan_pasha 

maybe check if there is some activities on the SDMMC2_CLK and SDMMC2_CMD. A clock might be missing.

See also this old post https://community.st.com/t5/stm32-mpus-products/stm32mp1-occasionally-emmc-boot-fail-with-quot-cmd13-failed/td-p/108285

https://wiki.st.com/stm32mpu/wiki/How_to_create_your_board_device_tree

Regards.

[adnan_pasha]

Hi @PatrickF 

I did check out this post it says after applying the patch the issue got resolved.
But I dont have any regulator_core.c file in /drivers/regulator/regulator_core.c path

But I do have it in the file at /drivers/st/regulator/regulator_core.c.

[adnan_pasha]

TFA version i am using is v2.8.15-stm32mp-r2-r0.

After commenting out the line return -EIO; in driver file /drivers/mmc/mmc.c in mmc_device_state() function
We are able to get emmc boot to work properly.

if (retries == 0) {
ERROR("CMD13 failed after %d retries\n",
MMC_DEFAULT_MAX_RETRIES);
//return -EIO;
}

Could you please let me know what this does and why it's was halting the boot process.


Thanks.

[PatrickF]

Hi,

maybe your eMMC need more time to answer CMD13

Regards.

[adnan_pasha · Accepted solution]

Hi,

I have reverted the changes I made and changed the max number of retries from 5 to 10 in the driver file. We are able to get emmc boot properly without error or panic message.

Thanks