diff options
| -rw-r--r-- | arch/arm/cpu/armv7/start.S | 5 | ||||
| -rw-r--r-- | arch/arm/cpu/armv7/sunxi/board.c | 35 | ||||
| -rw-r--r-- | arch/arm/cpu/armv7/sunxi/fel_utils.S | 17 |
3 files changed, 47 insertions, 10 deletions
diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S index 098a83a..9b49ece 100644 --- a/arch/arm/cpu/armv7/start.S +++ b/arch/arm/cpu/armv7/start.S @@ -54,8 +54,7 @@ save_boot_params_ret: * (OMAP4 spl TEXT_BASE is not 32 byte aligned. * Continue to use ROM code vector only in OMAP4 spl) */ -#if !(defined(CONFIG_OMAP44XX) && defined(CONFIG_SPL_BUILD)) && \ - !defined(CONFIG_SPL_FEL) +#if !(defined(CONFIG_OMAP44XX) && defined(CONFIG_SPL_BUILD)) /* Set V=0 in CP15 SCTLR register - for VBAR to point to vector */ mrc p15, 0, r0, c1, c0, 0 @ Read CP15 SCTLR Register bic r0, #CR_V @ V = 0 @@ -68,9 +67,7 @@ save_boot_params_ret: /* the mask ROM code should have PLL and others stable */ #ifndef CONFIG_SKIP_LOWLEVEL_INIT -#ifndef CONFIG_SPL_FEL bl cpu_init_cp15 -#endif bl cpu_init_crit #endif 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 */ diff --git a/arch/arm/cpu/armv7/sunxi/fel_utils.S b/arch/arm/cpu/armv7/sunxi/fel_utils.S index 0c1de52..bf00335 100644 --- a/arch/arm/cpu/armv7/sunxi/fel_utils.S +++ b/arch/arm/cpu/armv7/sunxi/fel_utils.S @@ -15,11 +15,28 @@ ENTRY(save_boot_params) ldr r0, =fel_stash str sp, [r0, #0] str lr, [r0, #4] + mrs lr, cpsr @ Read CPSR + str lr, [r0, #8] + mrc p15, 0, lr, c1, c0, 0 @ Read CP15 SCTLR Register + str lr, [r0, #12] + mrc p15, 0, lr, c12, c0, 0 @ Read VBAR + str lr, [r0, #16] + mrc p15, 0, lr, c1, c0, 0 @ Read CP15 Control Register + str lr, [r0, #20] b save_boot_params_ret ENDPROC(save_boot_params) ENTRY(return_to_fel) mov sp, r0 mov lr, r1 + ldr r0, =fel_stash + ldr r1, [r0, #20] + mcr p15, 0, r1, c1, c0, 0 @ Write CP15 Control Register + ldr r1, [r0, #16] + mcr p15, 0, r1, c12, c0, 0 @ Write VBAR + ldr r1, [r0, #12] + mcr p15, 0, r1, c1, c0, 0 @ Write CP15 SCTLR Register + ldr r1, [r0, #8] + msr cpsr, r1 @ Write CPSR bx lr ENDPROC(return_to_fel) |