sunxi: Increase SPL header size to 64 bytes to avoid code corruption
The current SPL header, created by the 'mksunxiboot' tool, has size
32 bytes. But the code in the boot ROM stores the information about
the boot media at the offset 0x28 before passing control to the SPL.
For example, when booting from the SD card, the magic number written
by the boot ROM is 0. And when booting from the SPI flash, the magic
number is 3. NAND and eMMC probably have their own special magic
numbers too.
Currently the corrupted byte is a part of one of the instructions in
the reset vectors table:
b reset
ldr pc, _undefined_instruction
ldr pc, _software_interrupt <- Corruption happens here
ldr pc, _prefetch_abort
ldr pc, _data_abort
ldr pc, _not_used
ldr pc, _irq
ldr pc, _fiq
In practice this does not cause any visible problems, but it's still
better to fix it. As a bonus, the reported boot media type can be
later used in the 'spl_boot_device' function, but this is out of
the scope of this patch.
Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/arch/arm/include/asm/arch-sunxi/spl.h b/arch/arm/include/asm/arch-sunxi/spl.h
index ca9a4f9..a0f33b0 100644
--- a/arch/arm/include/asm/arch-sunxi/spl.h
+++ b/arch/arm/include/asm/arch-sunxi/spl.h
@@ -18,6 +18,10 @@
#define SPL_ADDR 0x0
#endif
+/* The low 8-bits of the 'boot_media' field in the SPL header */
+#define SUNXI_BOOTED_FROM_MMC0 0
+#define SUNXI_BOOTED_FROM_SPI 3
+
/* boot head definition from sun4i boot code */
struct boot_file_head {
uint32_t b_instruction; /* one intruction jumping to real code */
@@ -45,7 +49,9 @@
uint8_t spl_signature[4];
};
uint32_t fel_script_address;
- uint32_t reserved; /* padding, align to 32 bytes */
+ uint32_t reserved1[3];
+ uint32_t boot_media; /* written here by the boot ROM */
+ uint32_t reserved2[5]; /* padding, align to 64 bytes */
};
#define is_boot0_magic(addr) (memcmp((void *)addr, BOOT0_MAGIC, 8) == 0)