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add SMT detection for newer AMD processors

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The change seems to be more in the nomenclature than in the way the
topology is advertised by the hardware.

Tested by:	truckman (earlier version of the change)
MFC after:	2 weeks
This commit is contained in:
avg 2017-03-27 09:45:27 +00:00
parent 4315cc14ea
commit 3caafc04f1
1 changed files with 16 additions and 0 deletions
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16
sys/x86/x86/mp_x86.c
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@ -255,6 +255,22 @@ topo_probe_amd(void)
pkg_id_shift =
mask_width((cpu_procinfo2 & AMDID_CMP_CORES) + 1);
/*
* Families prior to 16h define the following value as
* cores per compute unit and we don't really care about the AMD
* compute units at the moment. Perhaps we should treat them as
* cores and cores within the compute units as hardware threads,
* but that's up for debate.
* Later families define the value as threads per compute unit,
* so we are following AMD's nomenclature here.
*/
if ((amd_feature2 & AMDID2_TOPOLOGY) != 0 &&
CPUID_TO_FAMILY(cpu_id) >= 0x16) {
cpuid_count(0x8000001e, 0, p);
share_count = ((p[1] >> 8) & 0xff) + 1;
core_id_shift = mask_width(share_count);
}
if ((amd_feature2 & AMDID2_TOPOLOGY) != 0) {
for (i = 0; ; i++) {
cpuid_count(0x8000001d, i, p);