diff options
| author | Simon Glass | 2017-01-16 07:03:43 -0700 |
|---|---|---|
| committer | Bin Meng | 2017-02-06 11:38:46 +0800 |
| commit | a66ad67ff26a2c4940aa7b6ddba40cf202edf108 (patch) | |
| tree | 7924fe48c762df57952269fb00f7b8f7b69ed829 | |
| parent | 113e75592a8c9e3f49a2009fe4d5969ac3028bfd (diff) | |
x86: Add Kconfig options to build 64-bit U-Boot
Add a new CONFIG_X86_64 option which will eventually cause U-Boot to be
built as a 64-bit application, with SPL doing the 16/32-bit init.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
| -rw-r--r-- | arch/x86/Kconfig | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0884af22a79..5cd58d450b5 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -5,6 +5,52 @@ config SYS_ARCH default "x86" choice + prompt "Run U-Boot in 32/64-bit mode" + default X86_RUN_32BIT + help + U-Boot can be built as a 32-bit binary which runs in 32-bit mode + even on 64-bit machines. In this case SPL is not used, and U-Boot + runs directly from the reset vector (via 16-bit start-up). + + Alternatively it can be run as a 64-bit binary, thus requiring a + 64-bit machine. In this case SPL runs in 32-bit mode (via 16-bit + start-up) then jumps to U-Boot in 64-bit mode. + + For now, 32-bit mode is recommended, as 64-bit is still + experimental and is missing a lot of features. + +config X86_RUN_32BIT + bool "32-bit" + help + Build U-Boot as a 32-bit binary with no SPL. This is the currently + supported normal setup. U-Boot will stay in 32-bit mode even on + 64-bit machines. When booting a 64-bit kernel, U-Boot will switch + to 64-bit just before starting the kernel. Only the bottom 4GB of + memory can be accessed through normal means, although + arch_phys_memset() can be used for basic access to other memory. + +config X86_RUN_64BIT + bool "64-bit" + select X86_64 + select SUPPORT_SPL + select SPL + select SPL_SEPARATE_BSS + help + Build U-Boot as a 64-bit binary with a 32-bit SPL. This is + experimental and many features are missing. U-Boot SPL starts up, + runs through the 16-bit and 32-bit init, then switches to 64-bit + mode and jumps to U-Boot proper. + +endchoice + +config X86_64 + bool + +config SPL_X86_64 + bool + depends on SPL + +choice prompt "Mainboard vendor" default VENDOR_EMULATION |