efi_loader: Use system fdt as fallback

[oweals/u-boot.git] / cmd / bootefi.c

diff --git a/cmd/bootefi.c b/cmd/bootefi.c
index f502996a9619a434c52a36643122e70596e3e9dd..9b8af65052b8ff67b068dc95e5dbb60d1acb8f6b 100644 (file)
--- a/cmd/bootefi.c
+++ b/cmd/bootefi.c
@@ -12,6 +12,10 @@
 #include <errno.h>
 #include <libfdt.h>
 #include <libfdt_env.h>
+#include <malloc.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
 
 /*
  * When booting using the "bootefi" command, we don't know which
@@ -97,6 +101,21 @@ static struct efi_object bootefi_device_obj = {
        },
 };
 
+static void *copy_fdt(void *fdt)
+{
+       u64 fdt_size = fdt_totalsize(fdt);
+       void *new_fdt;
+
+       /* Give us 64kb breathing room */
+       fdt_size += 64 * 1024;
+
+       new_fdt = malloc(fdt_size);
+       memcpy(new_fdt, fdt, fdt_totalsize(fdt));
+       fdt_set_totalsize(new_fdt, fdt_size);
+
+       return new_fdt;
+}
+
 /*
  * Load an EFI payload into a newly allocated piece of memory, register all
  * EFI objects it would want to access and jump to it.
@@ -106,6 +125,7 @@ static unsigned long do_bootefi_exec(void *efi)
        ulong (*entry)(void *image_handle, struct efi_system_table *st);
        ulong fdt_pages, fdt_size, fdt_start, fdt_end;
        bootm_headers_t img = { 0 };
+       void *fdt = working_fdt;
 
        /*
         * gd lives in a fixed register which may get clobbered while we execute
@@ -115,28 +135,33 @@ static unsigned long do_bootefi_exec(void *efi)
 
        /* Update system table to point to our currently loaded FDT */
 
-       if (working_fdt) {
+       /* Fall back to included fdt if none was manually loaded */
+       if (!fdt && gd->fdt_blob)
+               fdt = (void *)gd->fdt_blob;
+
+       if (fdt) {
                /* Prepare fdt for payload */
-               if (image_setup_libfdt(&img, working_fdt, 0, NULL)) {
+               fdt = copy_fdt(fdt);
+
+               if (image_setup_libfdt(&img, fdt, 0, NULL)) {
                        printf("ERROR: Failed to process device tree\n");
                        return -EINVAL;
                }
 
                /* Link to it in the efi tables */
                systab.tables[0].guid = EFI_FDT_GUID;
-               systab.tables[0].table = working_fdt;
+               systab.tables[0].table = fdt;
                systab.nr_tables = 1;
 
                /* And reserve the space in the memory map */
-               fdt_start = ((ulong)working_fdt) & ~EFI_PAGE_MASK;
-               fdt_end = ((ulong)working_fdt) + fdt_totalsize(working_fdt);
+               fdt_start = ((ulong)fdt) & ~EFI_PAGE_MASK;
+               fdt_end = ((ulong)fdt) + fdt_totalsize(fdt);
                fdt_size = (fdt_end - fdt_start) + EFI_PAGE_MASK;
                fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
                /* Give a bootloader the chance to modify the device tree */
                fdt_pages += 2;
                efi_add_memory_map(fdt_start, fdt_pages,
                                   EFI_BOOT_SERVICES_DATA, true);
-
        } else {
                printf("WARNING: No device tree loaded, expect boot to fail\n");
                systab.nr_tables = 0;