Hi Simon,
On Fri, Feb 15, 2013 at 2:35 PM, Simon Glass sjg@chromium.org wrote:
Hi Graeme,
On Thu, Feb 14, 2013 at 2:36 PM, Graeme Russ graeme.russ@gmail.com wrote:
Hi Simon,
On Fri, Feb 15, 2013 at 1:18 AM, Simon Glass sjg@chromium.org wrote:
This code is pretty old and we want to support only 32-bit systems now. Keep the real mode-to-protected code in case we want to boot an x86 from power-up, but invert the polarity of the option.
Signed-off-by: Simon Glass sjg@chromium.org
[snip]
diff --git a/README b/README index 6106e0d..7b50720 100644 --- a/README +++ b/README @@ -3820,10 +3820,9 @@ Low Level (hardware related) configuration options: If defined, the x86 reset vector code is included. This is not needed when U-Boot is running from Coreboot.
-- CONFIG_X86_NO_REAL_MODE
If defined, x86 real mode code is omitted. This assumes a32-bit environment where such code is not needed. You willneed to do this when U-Boot is running from Coreboot.+- CONFIG_X86_REAL_MODE
If defined, some 86 real mode code is included. This is notneeded when U-Boot is running from Coreboot.I think this config option can be punted completely. This define is only used to pull in the real-mode trampoline code which switches from protected-mode to real-mode before jumping into the Linux kernel's real-mode stub. The code for the initial real-mode to protected-mode switch will be pulled in by CONFIG_X86_RESET_VECTOR
I suppose I am confused about what is needed here. I will drop the flag, and arch/x86/lib/realmode_switch.S. Is that right?
Correct. All you need to keep is:
arch/x86/cpu/resetvec.S arch/x86/cpu/start16
And these are conditional on CONFIG_X86_RESET_VECTOR
Looking at the most recent patch, I think you have it nailed now
Regards,
Graeme