From 935109cd9e97b2f48b177b7c31373325deab44c0 Mon Sep 17 00:00:00 2001 From: "Kory Maincent (TI.com)" Date: Thu, 30 Oct 2025 17:45:11 +0100 Subject: [PATCH] boot: pxe_utils: Add extension board devicetree overlay support Add support for scanning and applying extension board devicetree overlays during PXE boot. After loading the main board devicetree, the system now scans for available extension boards and applies their overlays automatically. This enables dynamic hardware configuration for systems with extension boards during boot scenarios which are using pxe_utils. Signed-off-by: Kory Maincent (TI.com) Reviewed-by: Simon Glass --- boot/pxe_utils.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++ doc/usage/pxe.rst | 4 +++ 2 files changed, 96 insertions(+) diff --git a/boot/pxe_utils.c b/boot/pxe_utils.c index eb4d7723481..038416203fc 100644 --- a/boot/pxe_utils.c +++ b/boot/pxe_utils.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -432,6 +433,95 @@ skip_overlay: } #endif +/* + * label_boot_extension - scan extension boards and load overlay associated + */ + +static void label_boot_extension(struct pxe_context *ctx, + struct pxe_label *label) +{ +#if CONFIG_IS_ENABLED(SUPPORT_EXTENSION_SCAN) + const struct extension *extension; + struct fdt_header *working_fdt; + struct alist *extension_list; + int ret, dir_len, len; + char *overlay_dir; + const char *slash; + ulong fdt_addr; + + ret = extension_scan(); + if (ret < 0) + return; + + extension_list = extension_get_list(); + if (!extension_list) + return; + + /* Get the main fdt and map it */ + fdt_addr = env_get_hex("fdt_addr_r", 0); + working_fdt = map_sysmem(fdt_addr, 0); + if (fdt_check_header(working_fdt)) + return; + + /* Use fdtdir for now as the overlay devicetree directory */ + if (label->fdtdir) { + len = strlen(label->fdtdir); + if (!len) + slash = "./"; + else if (label->fdtdir[len - 1] != '/') + slash = "/"; + else + slash = ""; + + dir_len = strlen(label->fdtdir) + strlen(slash) + 1; + overlay_dir = calloc(1, len); + if (!overlay_dir) + return; + + snprintf(overlay_dir, dir_len, "%s%s", label->fdtdir, + slash); + } else { + dir_len = 2; + snprintf(overlay_dir, dir_len, "/"); + } + + alist_for_each(extension, extension_list) { + char *overlay_file; + ulong size; + + len = dir_len + strlen(extension->overlay); + overlay_file = calloc(1, len); + if (!overlay_file) + goto cleanup; + + snprintf(overlay_file, len, "%s%s", overlay_dir, + extension->overlay); + + /* Load extension overlay file */ + ret = get_relfile_envaddr(ctx, overlay_file, + "extension_overlay_addr", + (enum bootflow_img_t)IH_TYPE_FLATDT, + &size); + if (ret < 0) { + printf("Failed loading overlay %s\n", overlay_file); + free(overlay_file); + continue; + } + + ret = extension_apply(working_fdt, size); + if (ret) { + printf("Failed applying overlay %s\n", overlay_file); + free(overlay_file); + continue; + } + free(overlay_file); + } + +cleanup: + free(overlay_dir); +#endif +} + /** * label_boot() - Boot according to the contents of a pxe_label * @@ -685,6 +775,8 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label) if (label->fdtoverlays) label_boot_fdtoverlay(ctx, label); #endif + label_boot_extension(ctx, label); + } else { bootm_argv[3] = NULL; } diff --git a/doc/usage/pxe.rst b/doc/usage/pxe.rst index c2dc11f218d..18532f182d5 100644 --- a/doc/usage/pxe.rst +++ b/doc/usage/pxe.rst @@ -103,6 +103,10 @@ Environment ``fdt_addr_r``. Required to use the ``fdtoverlays`` command in the PXE file. +``extension_overlay_addr`` + Location in RAM to temporarily store extension fdt overlay(s) + before applying them to the fdt blob stored at ``fdt_addr_r``. + ``pxe_label_override`` Override label to be used, if exists, instead of the default label. This will allow consumers to choose a pxe label at -- 2.47.3