sunxi: SPL: Factor out sunxi_get_boot_source()

The Boot ROM write some boot source ID (SD card, eMMC, SPI, ...) into
a certain location in SRAM, so the SPL can easily determine where to
load U-Boot proper from.
Factor out reading this value, as it will come in handy again shortly.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>

diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-sunxi/board.c
index aa1d2230c98f85d86997410a67d03bc00211c226..9c0cf718b8956a64489eb95647b4d574065b3e61 100644 (file)
--- a/arch/arm/mach-sunxi/board.c
+++ b/arch/arm/mach-sunxi/board.c
@@ -221,12 +221,22 @@ void s_init(void)
        eth_init_board();
 }
 
+#define SUNXI_INVALID_BOOT_SOURCE      -1
+
+static int sunxi_get_boot_source(void)
+{
+       if (!is_boot0_magic(SPL_ADDR + 4)) /* eGON.BT0 */
+               return SUNXI_INVALID_BOOT_SOURCE;
+
+       return readb(SPL_ADDR + 0x28);
+}
+
 /* The sunxi internal brom will try to loader external bootloader
  * from mmc0, nand flash, mmc2.
  */
 uint32_t sunxi_get_boot_device(void)
 {
-       int boot_source;
+       int boot_source = sunxi_get_boot_source();
 
        /*
         * When booting from the SD card or NAND memory, the "eGON.BT0"
@@ -244,11 +254,9 @@ uint32_t sunxi_get_boot_device(void)
         * binary over USB. If it is found, it determines where SPL was
         * read from.
         */
-       if (!is_boot0_magic(SPL_ADDR + 4)) /* eGON.BT0 */
-               return BOOT_DEVICE_BOARD;
-
-       boot_source = readb(SPL_ADDR + 0x28);
        switch (boot_source) {
+       case SUNXI_INVALID_BOOT_SOURCE:
+               return BOOT_DEVICE_BOARD;
        case SUNXI_BOOTED_FROM_MMC0:
        case SUNXI_BOOTED_FROM_MMC0_HIGH:
                return BOOT_DEVICE_MMC1;