[PATCH v3 3/4] sunxi: Support SPL in both eGON and TOC0 images

[Samuel Holland <samuel@sholland.org>]

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>
---

Changes in v3:
 - Fixed offset of magic passed to memcmp
 - Refactored functions to not return pointers (fixes ambiguous NULL)

Changes in v2:
 - Moved SPL header signature checks out of sunxi_image.h
 - Refactored SPL header signature checks to use fewer casts

 arch/arm/include/asm/arch-sunxi/spl.h |  2 --
 arch/arm/mach-sunxi/board.c           | 34 ++++++++++++++++++++++-----
 2 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/arch/arm/include/asm/arch-sunxi/spl.h b/arch/arm/include/asm/arch-sunxi/spl.h
index 58cdf806d9..157b11e489 100644
--- a/arch/arm/include/asm/arch-sunxi/spl.h
+++ b/arch/arm/include/asm/arch-sunxi/spl.h
@@ -19,8 +19,6 @@
 #define SUNXI_BOOTED_FROM_MMC0_HIGH	0x10
 #define SUNXI_BOOTED_FROM_MMC2_HIGH	0x12
 
-#define is_boot0_magic(addr)	(memcmp((void *)(addr), BOOT0_MAGIC, 8) == 0)
-
 uint32_t sunxi_get_boot_device(void);
 
 #endif
diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
index b4ba2a72c4..b2cd64bb3f 100644
--- a/arch/arm/mach-sunxi/board.c
+++ b/arch/arm/mach-sunxi/board.c
@@ -243,12 +243,28 @@ void s_init(void)
 
 #define SUNXI_INVALID_BOOT_SOURCE	-1
 
+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)
 {
-	if (!is_boot0_magic(SPL_ADDR + 4)) /* eGON.BT0 */
-		return SUNXI_INVALID_BOOT_SOURCE;
+	struct boot_file_head *egon_head = (void *)SPL_ADDR;
+	struct toc0_main_info *toc0_info = (void *)SPL_ADDR;
+
+	if (sunxi_egon_valid(egon_head))
+		return readb(&egon_head->boot_media);
+	if (sunxi_toc0_valid(toc0_info))
+		return readb(&toc0_info->platform[0]);
 
-	return readb(SPL_ADDR + 0x28);
+	/* 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
@@ -296,10 +312,16 @@ uint32_t sunxi_get_boot_device(void)
 #ifdef CONFIG_SPL_BUILD
 static u32 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;
 }
 
 /*
-- 
2.32.0