[PATCH] crypto: x86/crc32c-intel - Don't match some Zhaoxin CPUs

[Tony W Wang-oc]

The driver crc32c-intel match CPUs supporting X86_FEATURE_XMM4_2.
On platforms with Zhaoxin CPUs supporting this X86 feature, When
crc32c-intel and crc32c-generic are both registered, system will
use crc32c-intel because its .cra_priority is greater than
crc32c-generic. This case expect to use crc32c-generic driver for
some Zhaoxin CPUs to get performance gain, So remove these Zhaoxin
CPUs support from crc32c-intel.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@xxxxxxxxxxx>
---
 arch/x86/crypto/crc32c-intel_glue.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/x86/crypto/crc32c-intel_glue.c b/arch/x86/crypto/crc32c-intel_glue.c
index feccb52..6dafdae 100644
--- a/arch/x86/crypto/crc32c-intel_glue.c
+++ b/arch/x86/crypto/crc32c-intel_glue.c
@@ -222,8 +222,16 @@ MODULE_DEVICE_TABLE(x86cpu, crc32c_cpu_id);
 
 static int __init crc32c_intel_mod_init(void)
 {
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
 	if (!x86_match_cpu(crc32c_cpu_id))
 		return -ENODEV;
+
+	if (c->x86_vendor == X86_VENDOR_ZHAOXIN || c->x86_vendor == X86_VENDOR_CENTAUR) {
+		if (c->x86 == 0x6 || (c->x86 == 0x7 && c->x86_model <= 0x3b))
+			return -ENODEV;
+	}
+
 #ifdef CONFIG_X86_64
 	if (boot_cpu_has(X86_FEATURE_PCLMULQDQ)) {
 		alg.update = crc32c_pcl_intel_update;
-- 
2.7.4