mirror of
https://github.com/brain-hackers/u-boot-brain
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83843c9b3a
The Allwinner A64 SoC starts execution in AArch32 mode, and both the boot ROM and Allwinner's boot0 keep running in this mode. So U-Boot gets entered in 32-bit, although we want it to run in AArch64. By using a "magic" instruction, which happens to be an almost-NOP in AArch64 and a branch in AArch32, we differentiate between being entered in 64-bit or 32-bit mode. If in 64-bit mode, we proceed with the branch to reset, but in 32-bit mode we trigger an RMR write to bring the core into AArch64/EL3 and re-enter U-Boot at CONFIG_SYS_TEXT_BASE. This allows a 64-bit U-Boot to be both entered in 32 and 64-bit mode, so we can use the same start code for the SPL and the U-Boot proper. We use the existing custom header (boot0.h) functionality, but restrict the existing boot0 header reservation to the non-SPL build now. A SPL wouldn't need such header anyway. This allows to have both options defined and lets us use one for the SPL and the other for U-Boot proper. Also add arch/arm/mach-sunxi/rmr_switch.S, which contains the original ARM assembly code and instructions how to re-generate the encoded version. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Jagan Teki <jagan@openedev.com> |
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| .. | ||
| cpu | ||
| dts | ||
| imx-common | ||
| include | ||
| lib | ||
| mach-at91 | ||
| mach-bcm283x | ||
| mach-davinci | ||
| mach-exynos | ||
| mach-highbank | ||
| mach-integrator | ||
| mach-keystone | ||
| mach-kirkwood | ||
| mach-litesom | ||
| mach-meson | ||
| mach-mvebu | ||
| mach-omap2 | ||
| mach-orion5x | ||
| mach-rmobile | ||
| mach-rockchip | ||
| mach-s5pc1xx | ||
| mach-snapdragon | ||
| mach-socfpga | ||
| mach-stm32 | ||
| mach-sunxi | ||
| mach-tegra | ||
| mach-uniphier | ||
| mach-versatile | ||
| mach-zynq | ||
| thumb1/include/asm/proc-armv | ||
| config.mk | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||