x86: use ELF section to list CPU vendor specific code
Replace the hardcoded list of initialization functions for each CPU
vendor by a list in an ELF section, which is read at initialization in
arch/x86/kernel/cpu/cpu.c to fill the cpu_devs[] array. The ELF
section, named .x86cpuvendor.init, is reclaimed after boot, and
contains entries of type "struct cpu_vendor_dev" which associates a
vendor number with a pointer to a "struct cpu_dev" structure.
This first modification allows to remove all the VENDOR_init_cpu()
functions.
This patch also removes the hardcoded calls to early_init_amd() and
early_init_intel(). Instead, we add a "c_early_init" member to the
cpu_dev structure, which is then called if not NULL by the generic CPU
initialization code. Unfortunately, in early_cpu_detect(), this_cpu is
not yet set, so we have to use the cpu_devs[] array directly.
This patch is part of the Linux Tiny project, and is needed for
further patch that will allow to disable compilation of unused CPU
support code.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 693e353..cab4e56 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -63,7 +63,7 @@
int force_mwait __cpuinitdata;
-void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
+static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
{
if (cpuid_eax(0x80000000) >= 0x80000007) {
c->x86_power = cpuid_edx(0x80000007);
@@ -336,6 +336,7 @@
}
},
},
+ .c_early_init = early_init_amd,
.c_init = init_amd,
.c_size_cache = amd_size_cache,
};
@@ -345,3 +346,5 @@
cpu_devs[X86_VENDOR_AMD] = &amd_cpu_dev;
return 0;
}
+
+cpu_vendor_dev_register(X86_VENDOR_AMD, &amd_cpu_dev);
