[coreboot] [RFC] v3: cpu.c and cpu.h

[ron minnich]

On Mon, Aug 18, 2008 at 5:29 AM, Carl-Daniel Hailfinger
<c-d.hailfinger.devel.2006 at gmx.net> wrote:
> One thing that's quite a bit confusing in v3 is the mess of cpu.c and cpu.h.
>
> include/arch/x86/cpu.h defines lots of functions which should be in a .c
> file instead. They are:
> struct cpuid_result cpuid(u32 op);
> u32 cpuid_eax(u32 op);
> u32 cpuid_ebx(u32 op);
> u32 cpuid_ecx(u32 op);
> u32 cpuid_edx(u32 op);
> void get_fms(struct cpuinfo_x86 *c, u32 tfms);
> unsigned long read_cr0(void);
> void write_cr0(unsigned long cr0);
> void invd(void);
> void wbinvd(void);
> void enable_cache(void);
> void disable_cache(void);
> void cpu_relax(void);
> void hlt(void);

I want these in a .c. This is more romcc legacy. They should be in
stage1, callable from anywhere.

>
> arch/x86/geodelx/cpu.c is completely unused, but the contents look
> important. Why don't we call them?
>

I'm not there yet. As you know, the cpu stuff is not ready yet. Also,
there was the problem of how to think about the cpu "device". I am
almost there and intend to augment newboot.lyx with an appendix.

> northbridge/amd/k8/cpu.c is used.


The k8 has hardware that manages  pci, domain, and cpu stuff that
intermix due to hardware design. The C code also intermixed, but it
was confusing. That said, I am thinking to move that cpu code to the
arch tree at some point, which is why I broke it out.


>
> Can someone please illustrate the underlying architecture?

I"m going to write it up as soon as I can figure it out.


>
> (Background: I'm trying to add timestamping to printk, but I'm totally
> at a loss where I should place get_timestamp().)
>

amd cpu support I assume.

ron