[PATCH] arm: imx: imx9: scmi: Fix booting from USB

[João Paulo Gonçalves]

From: João Paulo Gonçalves <joao.goncalves at toradex.com>

On i.MX95, 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, set the environment location based on the ENV
config and not solely based on the boot device type.

---
Hello all,

The change was not tested on mainline, but with downstream
`toradex_imx_lf_v2024.04` U-Boot branch. In the past, i.MX8M had the
same problem and the solution was similar.

Best Regards,
João Paulo Gonçalves
---
 arch/arm/mach-imx/imx9/scmi/soc.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-imx/imx9/scmi/soc.c b/arch/arm/mach-imx/imx9/scmi/soc.c
index 13f13ca7d1056ac5a9f1b529b13e0d8dbe2462f1..2c052c38521793e1f6ab2dc5125afa3b5ca63d0f 100644
--- a/arch/arm/mach-imx/imx9/scmi/soc.c
+++ b/arch/arm/mach-imx/imx9/scmi/soc.c
@@ -633,9 +633,13 @@ enum env_location env_get_location(enum env_operation op, int prio)
 	if (prio)
 		return env_loc;
 
+	if (IS_ENABLED(CONFIG_ENV_IS_NOWHERE))
+		env_loc = ENVL_NOWHERE;
+
 	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 +647,14 @@ 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_IN_SPI_FLASH))
+			env_loc = ENVL_SPI_FLASH;
+		else if (IS_ENABLED(CONFIG_ENV_IS_IN_MMC))
+			env_loc = ENVL_MMC;
 		break;
 	}
 

---
base-commit: bd0ade7d090a334b3986936d63a34001d99722ad
change-id: 20250722-v1-fix-imx95-usb-boot-9e6d760be10e

Best regards,
-- 
João Paulo Gonçalves <joao.goncalves at toradex.com>