[PATCH v1 1/3] mach-sunxi: Add boot device detection for SUNIV

[Jesse Taube]

Use Samuel's suggestion of looking at the BootRom's stack
to determine the boot device.

Signed-off-by: Jesse Taube <Mr.Bossman075 at gmail.com>
Suggested-by: Samuel Holland <samuel at sholland.org>
---
 arch/arm/include/asm/arch-sunxi/spl.h | 15 ++++++++
 arch/arm/mach-sunxi/board.c           | 50 ++++++++++++---------------
 2 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/arch/arm/include/asm/arch-sunxi/spl.h b/arch/arm/include/asm/arch-sunxi/spl.h
index 58cdf806d9..d069091297 100644
--- a/arch/arm/include/asm/arch-sunxi/spl.h
+++ b/arch/arm/include/asm/arch-sunxi/spl.h
@@ -19,8 +19,23 @@
 #define SUNXI_BOOTED_FROM_MMC0_HIGH	0x10
 #define SUNXI_BOOTED_FROM_MMC2_HIGH	0x12
 
+/*
+ * Values taken from the Bootrom's stack used
+ * to determine where we booted from.
+ * 0xffff40f8: mmc0
+ * 0xffff4114: spi0 NAND
+ * 0xffff4130: spi0 NOR
+ * 0xffff4150: mmc1
+ */
+
+#define SUNIV_BOOTED_FROM_MMC0	0xffff40f8
+#define SUNIV_BOOTED_FROM_NAND	0xffff4114
+#define SUNIV_BOOTED_FROM_SPI	0xffff4130
+#define SUNIV_BOOTED_FROM_MMC1	0xffff4150
+
 #define is_boot0_magic(addr)	(memcmp((void *)(addr), BOOT0_MAGIC, 8) == 0)
 
 uint32_t sunxi_get_boot_device(void);
+uint32_t suniv_get_boot_device(void);
 
 #endif
diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
index 57078f7a7b..b0658d583e 100644
--- a/arch/arm/mach-sunxi/board.c
+++ b/arch/arm/mach-sunxi/board.c
@@ -241,6 +241,25 @@ uint32_t sunxi_get_boot_device(void)
 	return -1;		/* Never reached */
 }
 
+uint32_t suniv_get_boot_device(void)
+{
+	/* Get the last function call from BootRom's stack. */
+	u32 brom_call = *(u32 *)(fel_stash.sp - 4);
+
+	switch (brom_call) {
+	case SUNIV_BOOTED_FROM_MMC0:
+		return BOOT_DEVICE_MMC1;
+	case SUNIV_BOOTED_FROM_NAND:
+	case SUNIV_BOOTED_FROM_SPI:
+		return BOOT_DEVICE_SPI;
+	case SUNIV_BOOTED_FROM_MMC1:
+		return BOOT_DEVICE_MMC2;
+	}
+
+	printf("Unknown boot source from BROM: 0x%x\n", brom_call);
+	return BOOT_DEVICE_MMC1;
+}
+
 #ifdef CONFIG_SPL_BUILD
 static u32 sunxi_get_spl_size(void)
 {
@@ -276,36 +295,13 @@ unsigned long spl_mmc_get_uboot_raw_sector(struct mmc *mmc,
 	return sector;
 }
 
-#ifdef CONFIG_MACH_SUNIV
-/*
- * The suniv BROM does not pass the boot media type to SPL, so we try with the
- * boot sequence in BROM: mmc0->spinor->fail.
- * TODO: This has the slight chance of being wrong (invalid SPL signature,
- * but valid U-Boot legacy image on the SD card), but this should be rare.
- * It looks like we can deduce from some BROM state upon entering the SPL
- * (registers, SP, or stack itself) where the BROM was coming from and use
- * that here.
- */
-void board_boot_order(u32 *spl_boot_list)
-{
-	/*
-	 * See the comments above in sunxi_get_boot_device() for information
-	 * about FEL boot.
-	 */
-	if (!is_boot0_magic(SPL_ADDR + 4)) {
-		spl_boot_list[0] = BOOT_DEVICE_BOARD;
-		return;
-	}
-
-	spl_boot_list[0] = BOOT_DEVICE_MMC1;
-	spl_boot_list[1] = BOOT_DEVICE_SPI;
-}
-#else
 u32 spl_boot_device(void)
 {
-	return sunxi_get_boot_device();
+	if (IS_ENABLED(CONFIG_MACH_SUNIV))
+		return suniv_get_boot_device();
+	else
+		return sunxi_get_boot_device();
 }
-#endif
 
 __weak void sunxi_sram_init(void)
 {
-- 
2.34.1