boot: Warn users about fdt_high=~0 usage

In case the 'fdt_high' environment variable is set to ~0, warn users
about the dangers of the fdt_high usage. This will hopefully lead to
removal of most of the fdt_high ~0 usage over time.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

diff --git a/boot/image-fdt.c b/boot/image-fdt.c
index 3f0ac54f76fa21c57add76033592d6ba2b3cec9b..a3a4fb8b558fc01f3eee3ab2a3ffa975ba770daf 100644 (file)
--- a/boot/image-fdt.c
+++ b/boot/image-fdt.c
@@ -189,6 +189,12 @@ int boot_relocate_fdt(char **of_flat_tree, ulong *of_size)
                        /* All ones means use fdt in place */
                        of_start = fdt_blob;
                        addr = map_to_sysmem(fdt_blob);
+                       printf("WARNING:\n"
+                              "The 'fdt_high' environment variable is set to ~0. This is known to cause\n"
+                              "boot failures due to placement of DT at non-8-byte-aligned addresses.\n"
+                              "This system will likely fail to boot. Unset the 'fdt_high' environment\n"
+                              "variable and submit a fix upstream.\n");
+
                        err = lmb_alloc_mem(LMB_MEM_ALLOC_ADDR, 0, &addr,
                                            of_len, LMB_NONE);
                        if (err) {