2018-03-01 15:55+0000, Moger, Babu: > Radim, Thanks for your comments. I am working on the changes. > But, I need few clarifications on your comments. Please see inline. > > > -----Original Message----- > > From: Radim Krčmář [mailto:rkrc...@redhat.com] > > Sent: Wednesday, February 28, 2018 12:09 PM > > To: Moger, Babu <babu.mo...@amd.com> > > Cc: pbonz...@redhat.com; r...@twiddle.net; ehabk...@redhat.com; > > mtosa...@redhat.com; qemu-devel@nongnu.org; k...@vger.kernel.org; > > p...@polepetko.eu; Hook, Gary <gary.h...@amd.com> > > Subject: Re: [PATCH v2 2/5] target/i386: Populate AMD Processor Cache > > Information > > > > 2018-02-23 21:30-0500, Babu Moger: > > > From: Stanislav Lanci <p...@polepetko.eu> > > > > > > Adds information about cache size and topology from cpuid 0x8000001D > > leaf > > > for different cache types on AMD processors. > > > > > > Signed-off-by: Stanislav Lanci <p...@polepetko.eu> > > > Signed-off-by: Babu Moger <babu.mo...@amd.com> > > > --- > > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > > > @@ -3590,6 +3594,78 @@ void cpu_x86_cpuid(CPUX86State *env, > > > + *ebx = (L1D_LINE_SIZE - 1) | \ > > > + ((L1D_PARTITIONS - 1) << 12) | \ > > > + ((L1D_ASSOCIATIVITY - 1) << 22); > > > + *ecx = L1D_SETS - 1; > > > > These numbers seem to have the same meaning as CPUID 4, but have > > conflicting values. > > I am not sure about conflicting values. Looking at the specs(page 78 > CPUID_Fn8000001D_EBX_x00) > https://support.amd.com/TechDocs/54945_PPR_Family_17h_Models_00h-0Fh.pdf > It looks correct to me.
I agree. My comment is misplaced -- it should have been under the place that uses *_AMD macros. I wanted to point out that CPUID in QEMU is very Intel-focused and always contains CPUID leaf 4, which has fields of the very same meaning, but with different values. > > I think we should not expose CPUID 4 with AMD CPUs or at least when they > > have CPUID_EXT3_TOPOEXT (the latter is easier wrt. compatibility). > > Can you please elaborate on these comments? > Did you mean we should remove the check CPUID_EXT3_TOPOEXT and remove all > CPUID 4 references? CPUID 4 should have never been present when emulating AMD CPUs, but it's worse now that the numbers are conflicting. I meant to hide CPUID 4 for all AMD CPUs on future machine types, or at least when CPUID_EXT3_TOPOEXT is enabled. Keeping the current logic not a big problem as CPUID 4 should never be used by operating systems on AMD nor trusted inside a VM. Bringing the emulation closer to real state would be nice, but this can definitely be done later (aka never). > > The numbers looks like real hardware, > > Do you want me to change anything here? No, I was just commending, thanks.
