x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when available

Derive topology information from Extended Topology Enumeration (CPUID
function 0xB) when the information is available.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1524865681-112110-3-git-send-email-suravee.suthikulpanit@amd.com

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index bf27246..55361ee 100644 (file)
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -327,6 +327,7 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
 
        /* get information required for multi-node processors */
        if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
+               int err;
                u32 eax, ebx, ecx, edx;
 
                cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
@@ -344,6 +345,14 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
                                c->x86_max_cores /= smp_num_siblings;
                }
 
+               /*
+                * In case leaf B is available, use it to derive
+                * topology information.
+                */
+               err = detect_extended_topology(c);
+               if (!err)
+                       c->x86_coreid_bits = get_count_order(c->x86_max_cores);
+
                cacheinfo_amd_init_llc_id(c, cpu, node_id);
 
        } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
@@ -378,7 +387,6 @@ static void amd_detect_cmp(struct cpuinfo_x86 *c)
        c->phys_proc_id = c->initial_apicid >> bits;
        /* use socket ID also for last level cache */
        per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
-       amd_get_topology(c);
 }
 
 u16 amd_get_nb_id(int cpu)
@@ -821,6 +829,7 @@ static void init_amd(struct cpuinfo_x86 *c)
        /* Multi core CPU? */
        if (c->extended_cpuid_level >= 0x80000008) {
                amd_detect_cmp(c);
+               amd_get_topology(c);
                srat_detect_node(c);
        }