[PATCH v9 5/7] i386: Add support for CPUID_8000_001E for AMD

Babu Moger
2018-05-14T16:41:54Z

Populate threads/core_id/apic_ids/socket_id when CPUID_EXT3_TOPOEXT
feature is supported. This is required to support hyperthreading feature
on AMD CPUs. This is supported via CPUID_8000_001E extended functions.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Tested-by: Geoffrey McRae <geoff@hostfission.com>
---
include/hw/i386/topology.h | 6 ++++++
target/i386/cpu.c | 8 ++++++++
2 files changed, 14 insertions(+)

diff --git a/include/hw/i386/topology.h b/include/hw/i386/topology.h
index 1ebaee0f76..4af746e50c 100644
--- a/include/hw/i386/topology.h
+++ b/include/hw/i386/topology.h
@@ -145,4 +145,10 @@ static inline apic_id_t x86_apicid_from_cpu_idx(unsigned nr_cores,
return apicid_from_topo_ids(nr_cores, nr_threads, &topo);
}

+/* Definitions used on CPUID Leaf 0x8000001E */
+#define EXTENDED_APIC_ID(threads, socket_id, core_id, thread_id) \
+ ((threads) ? \
+ ((socket_id << 6) | (core_id << 1) | thread_id) : \
+ ((socket_id << 6) | core_id))
+
#endif /* HW_I386_TOPOLOGY_H */
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index c06a9f5ebe..18a7872b7d 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -4071,6 +4071,14 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
break;
}
break;
+ case 0x8000001E:
+ assert(cpu->core_id <= 255);
+ *eax = EXTENDED_APIC_ID((cs->nr_threads - 1),
+ cpu->socket_id, cpu->core_id, cpu->thread_id);
+ *ebx = (cs->nr_threads - 1) << 8 | cpu->core_id;
+ *ecx = cpu->socket_id;
+ *edx = 0;
+ break;
case 0xC0000000:
*eax = env->cpuid_xlevel2;
*ebx = 0;
--
2.17.0