Allocate a 1 MiB LMB region for fdtoverlay_addr_r when CONFIG_OF_LIBFDT_OVERLAY is enabled, allowing runtime application of DT overlays on Snapdragon platforms.
This is useful for Android-based boot flows where the final DT passed to the kernel must contain modified /firmware/android/fstab entries. One use case is redirecting system and vendor partitions to microSD storage instead of internal eMMC without rebuilding the base DTB. The allocation is conditional on CONFIG_OF_LIBFDT_OVERLAY and has no effect on boards that do not enable overlay support. Signed-off-by: Antony Kurniawan Soemardi <[email protected]> --- arch/arm/mach-snapdragon/board.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/mach-snapdragon/board.c b/arch/arm/mach-snapdragon/board.c index 5fb3240acc5a6dd23d93515029a596b5f77ebfa3..829a0109ac7807d692e127178f76d8822d5da5e2 100644 --- a/arch/arm/mach-snapdragon/board.c +++ b/arch/arm/mach-snapdragon/board.c @@ -555,6 +555,11 @@ int board_late_init(void) fdt_status |= !lmb_alloc(SZ_2M, &addr) ? env_set_hex("fdt_addr_r", addr) : 1; + if (IS_ENABLED(CONFIG_OF_LIBFDT_OVERLAY)) { + status |= !lmb_alloc(SZ_1M, &addr) ? + env_set_hex("fdtoverlay_addr_r", addr) : 1; + } + if (status || fdt_status) log_warning("%s: Failed to set run time variables\n", __func__); --- base-commit: f9ffeec4bdcf1da655a0ffea482062adde78fee8 change-id: 20260215-qcom-fdt-overlay-ec6b8d9d2a1b Best regards, -- Antony Kurniawan Soemardi <[email protected]>
