diff options
Diffstat (limited to 'arch/arm/cpu/armv7/sunxi/board.c')
| -rw-r--r-- | arch/arm/cpu/armv7/sunxi/board.c | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/arch/arm/cpu/armv7/sunxi/board.c b/arch/arm/cpu/armv7/sunxi/board.c index b7492ac..c02c015 100644 --- a/arch/arm/cpu/armv7/sunxi/board.c +++ b/arch/arm/cpu/armv7/sunxi/board.c @@ -30,6 +30,10 @@ struct fel_stash { uint32_t sp; uint32_t lr; + uint32_t cpsr; + uint32_t sctlr; + uint32_t vbar; + uint32_t cr; }; struct fel_stash fel_stash __attribute__((section(".data"))); @@ -108,15 +112,34 @@ void s_init(void) */ u32 spl_boot_device(void) { +#ifdef CONFIG_SPL_FEL /* - * Have we been asked to return to the FEL portion of the boot ROM? - * TODO: We need a more robust test here, or bracket this with - * #ifdef CONFIG_SPL_FEL. + * This is the legacy compile time configuration for a special FEL + * enabled build. It has many restrictions and can only boot over USB. */ - if (fel_stash.lr >= 0xffff0000 && fel_stash.lr < 0xffff4000) + return BOOT_DEVICE_BOARD; +#else + /* + * When booting from the SD card, the "eGON.BT0" signature is expected + * to be found in memory at the address 0x0004 (see the "mksunxiboot" + * tool, which generates this header). + * + * When booting in the FEL mode over USB, this signature is patched in + * memory and replaced with something else by the 'fel' tool. This other + * signature is selected in such a way, that it can't be present in a + * valid bootable SD card image (because the BROM would refuse to + * execute the SPL in this case). + * + * This branch is just making a decision at runtime whether to load + * the main u-boot binary from the SD card (if the "eGON.BT0" signature + * is found) or return to the FEL code in the BROM to wait and receive + * the main u-boot binary over USB. + */ + if (readl(4) == 0x4E4F4765 && readl(8) == 0x3054422E) /* eGON.BT0 */ + return BOOT_DEVICE_MMC1; + else return BOOT_DEVICE_BOARD; - - return BOOT_DEVICE_MMC1; +#endif } /* No confirmation data available in SPL yet. Hardcode bootmode */ |