Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1e1d7e25 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

x86/cpu/AMD: Evaluate smp_num_siblings early 



To support force disabling of SMT it's required to know the number of
thread siblings early. amd_get_topology() cannot be called before the APIC
driver is selected, so split out the part which initializes
smp_num_siblings and invoke it from amd_early_init().

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarIngo Molnar <mingo@kernel.org>
parent 119bff8a

arch/x86/kernel/cpu/amd.c

+13 −0
Original line number Diff line number Diff line
@@ -315,6 +315,17 @@ static void legacy_fixup_core_id(struct cpuinfo_x86 *c) 
	c->cpu_core_id %= cus_per_node;

}





static void amd_get_topology_early(struct cpuinfo_x86 *c)

{

	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {

		u32 eax, ebx, ecx, edx;



		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);

		smp_num_siblings = ((ebx >> 8) & 0xff) + 1;

	}

}



/*

 * Fixup core topology information for

 * (1) AMD multi-node processors
@@ -681,6 +692,8 @@ static void early_init_amd(struct cpuinfo_x86 *c) 
		set_cpu_bug(c, X86_BUG_AMD_E400);



	early_detect_mem_encrypt(c);



	amd_get_topology_early(c);

}



static void init_amd_k8(struct cpuinfo_x86 *c)