[PATCH v2] arm: imx: imx9: soc: Fix env location when booting from USB

[Frieder Schrempf]

Am 11.08.25 um 14:57 schrieb João Paulo Gonçalves:
> From: João Paulo Gonçalves <joao.goncalves at toradex.com>
> 
> On i.MX9 platforms, when booting from USB, the U-Boot environment is
> always assumed to be in RAM. However, this causes the boot to hang when
> `CONFIG_ENV_IS_NOWHERE` is not enabled. The boot also hangs even if the
> environment is present in another storage media (for example, eMMC). Fix
> the issue by correctly handling the U-Boot environment's location when
> booting from USB. Also for i.MX95, set the environment location based on
> the ENV config and not solely based on the boot device type.
> 
> Suggested-by: Frieder Schrempf <frieder.schrempf at kontron.de>
> Signed-off-by: João Paulo Gonçalves <joao.goncalves at toradex.com>

Thanks! It works fine for the USB boot case for me on i.MX93 with both
CONFIG_ENV_IS_NOWHERE enabled and disabled.

One thing I noticed, though: For the SCMI case (i.MX95) we will leave
env_get_location() with ENVL_UNKNOWN in case of QSPI/SD/MMC boot if the
corresponding env device is not enabled. For i.MX93 instead we return
ENVL_NOWHERE (again without checking if ENVL_NOWHERE is enabled).

What would be the "correct" approach and can we align both platforms?

> ---
> v2:
> - Changed the env location order on USB boot to maintain current
> behavior on i.MX9
> - Applied the fix to other i.MX9 platforms, not only i.MX95
> - Added Suggested-by: Frieder Schrempf
> v1: https://lore.kernel.org/u-boot/20250722-v1-fix-imx95-usb-boot-v1-1-dec7f2384405@toradex.com/
> ---
>  arch/arm/mach-imx/imx9/scmi/soc.c | 13 ++++++++++---
>  arch/arm/mach-imx/imx9/soc.c      |  8 +++++++-
>  2 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm/mach-imx/imx9/scmi/soc.c b/arch/arm/mach-imx/imx9/scmi/soc.c
> index 13f13ca7d1056ac5a9f1b529b13e0d8dbe2462f1..f973652d0cbe8723b0cdc1a6235fbdd719146065 100644
> --- a/arch/arm/mach-imx/imx9/scmi/soc.c
> +++ b/arch/arm/mach-imx/imx9/scmi/soc.c
> @@ -635,7 +635,8 @@ enum env_location env_get_location(enum env_operation op, int prio)
>  
>  	switch (dev) {
>  	case QSPI_BOOT:
> -		env_loc = ENVL_SPI_FLASH;
> +		if (IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH))
> +			env_loc = ENVL_SPI_FLASH;
>  		break;
>  	case SD1_BOOT:
>  	case SD2_BOOT:
> @@ -643,10 +644,16 @@ enum env_location env_get_location(enum env_operation op, int prio)
>  	case MMC1_BOOT:
>  	case MMC2_BOOT:
>  	case MMC3_BOOT:
> -		env_loc =  ENVL_MMC;
> +		if (IS_ENABLED(CONFIG_ENV_IS_IN_MMC))
> +			env_loc =  ENVL_MMC;
>  		break;
>  	default:
> -		env_loc = ENVL_NOWHERE;
> +		if (IS_ENABLED(CONFIG_ENV_IS_NOWHERE))
> +			env_loc = ENVL_NOWHERE;
> +		else if (IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH))
> +			env_loc = ENVL_SPI_FLASH;
> +		else if (IS_ENABLED(CONFIG_ENV_IS_IN_MMC))
> +			env_loc = ENVL_MMC;
>  		break;
>  	}
>  
> diff --git a/arch/arm/mach-imx/imx9/soc.c b/arch/arm/mach-imx/imx9/soc.c
> index 9fb82644f126b8717b2f2ba1c9e77fb75d2e7757..3f7dafdcce5d3c6df102fe0a2a5d0b61c394937b 100644
> --- a/arch/arm/mach-imx/imx9/soc.c
> +++ b/arch/arm/mach-imx/imx9/soc.c
> @@ -809,7 +809,13 @@ enum env_location env_get_location(enum env_operation op, int prio)
>  			return ENVL_FAT;
>  		return ENVL_NOWHERE;
>  	default:
> -		return ENVL_NOWHERE;
> +		if (IS_ENABLED(CONFIG_ENV_IS_NOWHERE))
> +			return ENVL_NOWHERE;
> +		else if (IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH))
> +			return ENVL_SPI_FLASH;
> +		else if (IS_ENABLED(CONFIG_ENV_IS_IN_MMC))
> +			return ENVL_MMC;
> +		return ENVL_UNKNOWN;
>  	}
>  }
>  
> 
> ---
> base-commit: b6e2cfca1a6fd10c8f12016a40d690d2ec61796c
> change-id: 20250811-v2-fix-imx9-usb-boot-48679993463d
> 
> Best regards,