Commit ed78467a authored by Babu Moger's avatar Babu Moger Committed by Eduardo Habkost
Browse files

i386: Add support for CPUID_8000_001E for AMD 



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: default avatarBabu Moger <babu.moger@amd.com>
Message-Id: <1528498581-131037-2-git-send-email-babu.moger@amd.com>
Signed-off-by: default avatarEduardo Habkost <ehabkost@redhat.com>
parent 7ed14cbf

target/i386/cpu.c

+86 −0
Original line number Diff line number Diff line
@@ -427,6 +427,87 @@ 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 index for this core in the topology

     * This can be 0,1,2,3 with max 4 cores in a core complex

     */

    int core_id;

    /* Node id for this core index */

    int node_id;

    /* Number of nodes in this config */

    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;

    topo->num_nodes = nodes;

}



/* 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;

    /*

     * CPUID_Fn8000001E_EBX

     * 31:16 Reserved

     * 15:8  Threads per core (The number of threads per core is

     *       Threads per core + 1)

     *  7:0  Core id (see bit decoding below)

     *       SMT:

     *           4:3 node id

     *             2 Core complex id

     *           1:0 Core id

     *       Non SMT:

     *           5:4 node id

     *             3 Core complex id

     *           1:0 Core 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;

    }

    /*

     * CPUID_Fn8000001E_ECX

     * 31:11 Reserved

     * 10:8  Nodes per processor (Nodes per processor is number of nodes + 1)

     *  7:0  Node id (see bit decoding below)

     *         2  Socket id

     *       1:0  Node id

     */

    *ecx = ((topo.num_nodes - 1) << 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
@@ -4120,6 +4201,11 @@ 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;