[PATCH v11 3/5] i386: Add support for CPUID_8000_001E for AMD

Babu Moger
2018-05-24T15:43:32Z

Add support for cpuid leaf CPUID_8000_001E. Build the config that closely
match the underlying hardware. Please refer to the Processor Programming
Reference (PPR) for AMD Family 17h Model for more details.

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
target/i386/cpu.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 61 insertions(+)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 0d423e5..9f8bad9 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -429,6 +429,62 @@ static void encode_cache_cpuid8000001d(CPUCacheInfo *cache, CPUState *cs,
(cache->complex_indexing ? CACHE_COMPLEX_IDX : 0);
}

+/* Data structure to hold the configuration info for a given core index */
+struct core_topology {
+ /* core complex id of the current core index */
+ int ccx_id;
+ /* Adjusted core id for this core index in the topology */
+ int core_id;
+ /* Node id for this core index */
+ int node_id;
+ /* Number of nodes in this config, 0 based */
+ int num_nodes;
+};
+
+/*
+ * Build the configuration closely match the EPYC hardware. Using the EPYC
+ * hardware configuration values (MAX_CCX, MAX_CORES_IN_CCX, MAX_CORES_IN_NODE)
+ * right now. This could change in future.
+ * nr_cores : Total number of cores in the config
+ * core_id : Core index of the current CPU
+ * topo : Data structure to hold all the config info for this core index
+ */
+static void build_core_topology(int nr_cores, int core_id,
+ struct core_topology *topo)
+{
+ int nodes, cores_in_ccx;
+
+ /* First get the number of nodes required */
+ nodes = nodes_in_socket(nr_cores);
+
+ cores_in_ccx = cores_in_core_complex(nr_cores);
+
+ topo->node_id = core_id / (cores_in_ccx * MAX_CCX);
+ topo->ccx_id = (core_id % (cores_in_ccx * MAX_CCX)) / cores_in_ccx;
+ topo->core_id = core_id % cores_in_ccx;
+ /* num_nodes is 0 based, return n - 1 */
+ topo->num_nodes = nodes - 1;
+}
+
+/* Encode cache info for CPUID[8000001E] */
+static void encode_topo_cpuid8000001e(CPUState *cs, X86CPU *cpu,
+ uint32_t *eax, uint32_t *ebx,
+ uint32_t *ecx, uint32_t *edx)
+{
+ struct core_topology topo = {0};
+
+ build_core_topology(cs->nr_cores, cpu->core_id, &topo);
+ *eax = cpu->apic_id;
+ if (cs->nr_threads - 1) {
+ *ebx = ((cs->nr_threads - 1) << 8) | (topo.node_id << 3) |
+ (topo.ccx_id << 2) | topo.core_id;
+ } else {
+ *ebx = (topo.node_id << 4) | (topo.ccx_id << 3) | topo.core_id;
+ }
+ *ecx = (topo.num_nodes << 8) | (cpu->socket_id << 2) | topo.node_id;
+ *edx = 0;
+}
+
/*
* Definitions of the hardcoded cache entries we expose:
* These are legacy cache values. If there is a need to change any
@@ -4122,6 +4178,11 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
break;
}
break;
+ case 0x8000001E:
+ assert(cpu->core_id <= 255);
+ encode_topo_cpuid8000001e(cs, cpu,
+ eax, ebx, ecx, edx);
+ break;
case 0xC0000000:
*eax = env->cpuid_xlevel2;
*ebx = 0;
--
1.8.3.1