On Thu, Sep 4, 2008 at 8:32 AM, Carl-Daniel Hailfinger c-d.hailfinger.devel.2006@gmx.net wrote:
Hi,
I decided to look at all cases of inline asm in our v3 code and I found a few bits which either work by accident or need better documentation.
We use __asm__ and asm, __volatile__ and volatile. Can we please decide which one we want, then I'll switch the tree over.
somebody who knows better than me the implications can comment.
northbridge/amd/geodelx/vsmsetup.c:143
__asm__(".text\n" "real_mode_switch_end:\n"); extern char real_mode_switch_end[];
AFAICS the compiler and linker are free to place the resulting code anywhere in the binary independent of each other.
Not a problem. The "extern" is simply making the label available to C. They don't depend on any trickiness.
include/arch/x86/amd/k8/k8.h:746
static void disable_cache_as_ram_bsp(void) { __asm__ volatile ( // "pushl %eax\n\t" "pushl %edx\n\t" "pushl %ecx\n\t" );
disable_cache_as_ram(); __asm__ volatile ( "popl %ecx\n\t" "popl %edx\n\t"// "popl %eax\n\t" ); }
The pushl and popl instructions seem to serve no real purpose. Kill them?
My rule with the Clever v2 code is not to modify it until I understand it. So I did not touch these because I don't know what function they serve. That's one reason that I am bringing code over and leaving it ugly to start. Let's leave this alone until K8 is working.
The K8 CAR disabling has inline asm depending on good compiler behaviour and luck. Patch will be sent separately.
Thank you.
ron