[PATCH] qcom_defconfig: Switch Qualcomm fastboot flash from MMC to block

[Balaji Selvanathan]

On 2/20/2026 2:39 PM, Sumit Garg wrote:
> Hi Balaji,
>
> On Mon, Feb 16, 2026 at 09:45:49PM +0530, Balaji Selvanathan wrote:
>> Replace MMC-specific fastboot flash configuration with generic
>> block device support for Qualcomm platforms. This change switches
>> from MMC device 0 to SCSI interface with device ID 4, enabling
>> fastboot operations on UFS storage instead of eMMC.
> I don't think if it's right for qcom generic defconfig to hardcode
> fastboot flash device. Can you try to see rather if the fastboot flash
> device can be determined at runtime? As otherwise it might end up in
> target specific defconfig which we should avoid if we can.

Hi Sumit,

Implemented the runtime determination of fastboot device in : 
https://lore.kernel.org/u-boot/20260427-fb_gpt-v2-0-9e7fe3c1649a@oss.qualcomm.com/

However, I think we need to assign 
CONFIG_FASTBOOT_FLASH_BLOCK_DEVICE_ID, so that if user doesnt provide 
device number in the fastboot commands, then we can use the device 
mentioned in CONFIG_FASTBOOT_FLASH_BLOCK_DEVICE_ID as default.

Thanks,

Balaji

>
> -Sumit
>
>> Signed-off-by: Balaji Selvanathan <balaji.selvanathan at oss.qualcomm.com>
>> ---
>>   configs/qcom_defconfig | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/configs/qcom_defconfig b/configs/qcom_defconfig
>> index fe5880de1fd..2666adb0569 100644
>> --- a/configs/qcom_defconfig
>> +++ b/configs/qcom_defconfig
>> @@ -77,8 +77,9 @@ CONFIG_SYS_DFU_DATA_BUF_SIZE=0x200000
>>   CONFIG_USB_FUNCTION_FASTBOOT=y
>>   CONFIG_FASTBOOT_BUF_ADDR=0x0
>>   CONFIG_FASTBOOT_FLASH=y
>> -CONFIG_FASTBOOT_FLASH_MMC_DEV=0
>> -CONFIG_FASTBOOT_MMC_USER_SUPPORT=y
>> +CONFIG_FASTBOOT_FLASH_BLOCK=y
>> +CONFIG_FASTBOOT_FLASH_BLOCK_INTERFACE_NAME="scsi"
>> +CONFIG_FASTBOOT_FLASH_BLOCK_DEVICE_ID=4
>>   CONFIG_MSM_GPIO=y
>>   CONFIG_QCOM_PMIC_GPIO=y
>>   CONFIG_DM_I2C=y
>>
>> ---
>> base-commit: f9ffeec4bdcf1da655a0ffea482062adde78fee8
>> change-id: 20260216-fb_block-6193ec15ccf6
>>
>> Best regards,
>> -- 
>> Balaji Selvanathan <balaji.selvanathan at oss.qualcomm.com>
>>