From: Andre Przywara andre.przywara@arm.com
Some SPL loaders (like Allwinner's boot0, and Broadcom's boot0) require a header before the actual U-Boot binary to both check its validity and to find other data to load. Sometimes this header may only be a few bytes of information, and sometimes this might simply be space that needs to be reserved for a post-processing tool.
Introduce a config option to allow assembler preprocessor commands to be inserted into the code at the appropriate location; typical assembler preprocessor commands might be: .space 1000 .word 0x12345678
Signed-off-by: Andre Przywara andre.przywara@arm.com Signed-off-by: Steve Rae srae@broadcom.com Commit Notes: Please note that the current code: start.S (arm64) and vectors.S (arm) already jumps over some portion of data already, so this option basically just increases the size of this region (and the resulting binary).
For use with Allwinner's boot0 blob there is a tool called boot0img[1], which fills the header to allow booting A64 based boards. For the Pine64 we need a 1536 byte header (including the branch instruction) at the moment, so we add this to the defconfig.
[1] https://github.com/apritzel/pine64/tree/master/tools END
---
Changes in v4: as per Tom Rini trini@konsulko.com: - move definitions out of the "include/configs/*" files - rename definitions and moved some of the commit message into commit notes.
Changes in v3: ( v3 submitted by: Steve Rae srae@broadcom.com at the request of: Andre Przywara andre.przywara@arm.com ) - changed from just reserving space (with the .space command) to executing the assembler preprocessor commands ( also updated the subject and the original commit messaage )
Changes in v2: ( by: Andre Przywara andre.przywara@arm.com )
Changes in v1: ( by: Andre Przywara andre.przywara@arm.com )
arch/arm/Kconfig | 8 ++++++++ arch/arm/cpu/armv8/start.S | 10 ++++++++++ arch/arm/include/asm/arch-bcm281xx/boot0.h | 15 +++++++++++++++ arch/arm/include/asm/arch-sunxi/boot0.h | 14 ++++++++++++++ arch/arm/lib/vectors.S | 10 ++++++++++ configs/bcm28155_ap_defconfig | 1 + configs/bcm28155_w1d_defconfig | 1 + configs/pine64_plus_defconfig | 1 + 8 files changed, 60 insertions(+) create mode 100644 arch/arm/include/asm/arch-bcm281xx/boot0.h create mode 100644 arch/arm/include/asm/arch-sunxi/boot0.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 5fd20b9..ddd49b1 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -77,6 +77,14 @@ config SYS_L2CACHE_OFF If SoC does not support L2CACHE or one do not want to enable L2CACHE, choose this option.
+config ENABLE_ARM_SOC_BOOT0_HOOK + bool "prepare BOOT0 header" + help + If the SoC's BOOT0 requires a header area filled with (magic) + values, then choose this option, and create a define called + ARM_SOC_BOOT0_HOOK which contains the required assembler + preprocessor code. + choice prompt "Target select" default TARGET_HIKEY diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S index e933021..c1a2f45 100644 --- a/arch/arm/cpu/armv8/start.S +++ b/arch/arm/cpu/armv8/start.S @@ -21,6 +21,16 @@ _start: b reset
+#ifdef CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK +/* + * Various SoCs need something special and SoC-specific up front in + * order to boot, allow them to set that in their boot0.h file and then + * use it here. + */ +#include <asm/arch/boot0.h> +ARM_SOC_BOOT0_HOOK +#endif + .align 3
.globl _TEXT_BASE diff --git a/arch/arm/include/asm/arch-bcm281xx/boot0.h b/arch/arm/include/asm/arch-bcm281xx/boot0.h new file mode 100644 index 0000000..7e72882 --- /dev/null +++ b/arch/arm/include/asm/arch-bcm281xx/boot0.h @@ -0,0 +1,15 @@ +/* + * Copyright 2016 Broadcom Corporation. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __BOOT0_H +#define __BOOT0_H + +/* BOOT0 header information */ +#define ARM_SOC_BOOT0_HOOK \ + .word 0xbabeface; \ + .word _end - _start + +#endif /* __BOOT0_H */ diff --git a/arch/arm/include/asm/arch-sunxi/boot0.h b/arch/arm/include/asm/arch-sunxi/boot0.h new file mode 100644 index 0000000..ea5675e --- /dev/null +++ b/arch/arm/include/asm/arch-sunxi/boot0.h @@ -0,0 +1,14 @@ +/* + * Configuration settings for the Allwinner A64 (sun50i) CPU + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __BOOT0_H +#define __BOOT0_H + +/* reserve space for BOOT0 header information */ +#define ARM_SOC_BOOT0_HOOK \ + .space 1532 + +#endif /* __BOOT0_H */ diff --git a/arch/arm/lib/vectors.S b/arch/arm/lib/vectors.S index 49238ed..5cc132b 100644 --- a/arch/arm/lib/vectors.S +++ b/arch/arm/lib/vectors.S @@ -60,6 +60,16 @@ _start: ldr pc, _irq ldr pc, _fiq
+#ifdef CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK +/* + * Various SoCs need something special and SoC-specific up front in + * order to boot, allow them to set that in their boot0.h file and then + * use it here. + */ +#include <asm/arch/boot0.h> +ARM_SOC_BOOT0_HOOK +#endif + /* ************************************************************************* * diff --git a/configs/bcm28155_ap_defconfig b/configs/bcm28155_ap_defconfig index bfd519e..4404f32 100644 --- a/configs/bcm28155_ap_defconfig +++ b/configs/bcm28155_ap_defconfig @@ -22,3 +22,4 @@ CONFIG_G_DNL_MANUFACTURER="Broadcom Corporation" CONFIG_G_DNL_VENDOR_NUM=0x18d1 CONFIG_G_DNL_PRODUCT_NUM=0x0d02 CONFIG_OF_LIBFDT=y +CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK=y diff --git a/configs/bcm28155_w1d_defconfig b/configs/bcm28155_w1d_defconfig index 1911122..60eb328 100644 --- a/configs/bcm28155_w1d_defconfig +++ b/configs/bcm28155_w1d_defconfig @@ -22,3 +22,4 @@ CONFIG_USB_GADGET_DOWNLOAD=y CONFIG_G_DNL_MANUFACTURER="Broadcom Corporation" CONFIG_G_DNL_VENDOR_NUM=0x18d1 CONFIG_G_DNL_PRODUCT_NUM=0x0d02 +CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK=y diff --git a/configs/pine64_plus_defconfig b/configs/pine64_plus_defconfig index 489b75c..0bf79bf 100644 --- a/configs/pine64_plus_defconfig +++ b/configs/pine64_plus_defconfig @@ -9,3 +9,4 @@ CONFIG_DEFAULT_DEVICE_TREE="sun50i-a64-pine64-plus" # CONFIG_CMD_IMLS is not set # CONFIG_CMD_FLASH is not set # CONFIG_CMD_FPGA is not set +CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK=y