sunxi: Support SPL in both eGON and TOC0 images

SPL uses the image header to detect the boot device and to find the
offset of the next U-Boot stage. Since this information is stored
differently in the eGON and TOC0 image headers, add code to find the
correct value based on the image type currently in use.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
index 9a7673d..ffe578d 100644
--- a/arch/arm/mach-sunxi/board.c
+++ b/arch/arm/mach-sunxi/board.c
@@ -213,8 +213,21 @@
 	return SUNXI_INVALID_BOOT_SOURCE;
 }
 
+static int sunxi_egon_valid(struct boot_file_head *egon_head)
+{
+	return !memcmp(egon_head->magic, BOOT0_MAGIC, 8); /* eGON.BT0 */
+}
+
+static int sunxi_toc0_valid(struct toc0_main_info *toc0_info)
+{
+	return !memcmp(toc0_info->name, TOC0_MAIN_INFO_NAME, 8); /* TOC0.GLH */
+}
+
 static int sunxi_get_boot_source(void)
 {
+	struct boot_file_head *egon_head = (void *)SPL_ADDR;
+	struct toc0_main_info *toc0_info = (void *)SPL_ADDR;
+
 	/*
 	 * On the ARMv5 SoCs, the SPL header in SRAM is overwritten by the
 	 * exception vectors in U-Boot proper, so we won't find any
@@ -226,13 +239,15 @@
 	    !IS_ENABLED(CONFIG_SPL_BUILD))
 		return SUNXI_BOOTED_FROM_MMC0;
 
-	if (!is_boot0_magic(SPL_ADDR + 4)) /* eGON.BT0 */
-		return SUNXI_INVALID_BOOT_SOURCE;
-
 	if (IS_ENABLED(CONFIG_MACH_SUNIV))
 		return suniv_get_boot_source();
-	else
-		return readb(SPL_ADDR + 0x28);
+	if (sunxi_egon_valid(egon_head))
+		return readb(&egon_head->boot_media);
+	if (sunxi_toc0_valid(toc0_info))
+		return readb(&toc0_info->platform[0]);
+
+	/* Not a valid image, so we must have been booted via FEL. */
+	return SUNXI_INVALID_BOOT_SOURCE;
 }
 
 /* The sunxi internal brom will try to loader external bootloader
@@ -278,12 +293,18 @@
 }
 
 #ifdef CONFIG_SPL_BUILD
-static u32 sunxi_get_spl_size(void)
+uint32_t sunxi_get_spl_size(void)
 {
-	if (!is_boot0_magic(SPL_ADDR + 4)) /* eGON.BT0 */
-		return 0;
+	struct boot_file_head *egon_head = (void *)SPL_ADDR;
+	struct toc0_main_info *toc0_info = (void *)SPL_ADDR;
 
-	return readl(SPL_ADDR + 0x10);
+	if (sunxi_egon_valid(egon_head))
+		return readl(&egon_head->length);
+	if (sunxi_toc0_valid(toc0_info))
+		return readl(&toc0_info->length);
+
+	/* Not a valid image, so use the default U-Boot offset. */
+	return 0;
 }
 
 /*