On 1/9/26 03:10, Ewan Hai wrote:
Update the comment for FEAT_C000_0001_EDX in YongFeng CPU model to
accurately list the missing features instead of the generic TODO message.
As background, current Zhaoxin CPUs implement several CPUID.(EAX=0xC0000001,
ECX=0):EDX feature bits that are not yet defined in the Linux kernel, for
example SM2/SM2_EN, SM3/SM4 and their enable bits, PARALLAX/PARALLAX_EN,
TM3/TM3_EN, RNG2/RNG2_EN, PHE2/PHE2_EN, and RSA/RSA_EN.
We previously tried to upstream all these extra feature bits in one patch
(https://lore.kernel.org/all/[email protected]/),
but the maintainer rejected it because there was no in-tree code using these
features yet. So our current plan is to add the CPUID bits together with real
kernel users step by step, Once full or partial in-tree implementations of
these features are merged, we will update these definitions accordingly and
potentially introduce corresponding support in QEMU.
KVM now has a mechanism for introducing feature bits separately from the
kernel. Feel free to resumit using that mechanism, then we can include
them from the beginning in Shinjidadao.
Thanks,
Paolo
Signed-off-by: Ewan Hai <[email protected]>
---
target/i386/cpu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 34e3e66344..10603eeb31 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6958,8 +6958,8 @@ static const X86CPUDefinition builtin_x86_defs[] = {
CPUID_EXT3_3DNOWPREFETCH | CPUID_EXT3_ABM | CPUID_EXT3_LAHF_LM,
.features[FEAT_8000_0007_EDX] = CPUID_APM_INVTSC,
/*
- * TODO: When the Linux kernel introduces other existing definitions
- * for this leaf, remember to update the definitions here.
+ * missing: SM2/SM2_EN, CCS/CCS_EN, PARALLAX/PARALLAX_EN,
+ * TM3/TM3_EN, RNG2/RNG2_EN, PHE2/PHE2_EN, RSA/RSA_EN
*/
.features[FEAT_C000_0001_EDX] =
CPUID_C000_0001_EDX_PMM_EN | CPUID_C000_0001_EDX_PMM |
