On Thu, Mar 17, 2016 at 9:39 AM, Bin Meng bmeng.cn@gmail.com wrote:
On Wed, Mar 16, 2016 at 9:44 PM, Simon Glass sjg@chromium.org wrote:
Sometimes it is useful to jump into U-Boot directly from coreboot or UEFI without any 16-bit init. This can help during development by allowing U-Boot to avoid doing all the init required by the platform.
U-Boot expects its GDT to be set up correctly by its 16-bit code. If coreboot doesn't do this (because it hasn't run the payload setup code yet) then this won't happen.
In this case we cannot rely on the GDT settings. U-Boot will hang or crash if these are wrong. Provide a development-only option to set up the GDT correctly. This is just a hack so you can jump to U-Boot from any stage of coreboot, not just at the end.
Signed-off-by: Simon Glass sjg@chromium.org
Changes in v3:
- Add more detail to the commit message and code comments
Changes in v2: None
arch/x86/cpu/start.S | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+)
Reviewed-by: Bin Meng bmeng.cn@gmail.com
applied to u-boot-x86, thanks!