x86/fpu: Move CPUID leaf definitions to common code

Move the XSAVE-related CPUID leaf definitions to common code.  Then,
use the new definition to remove the last magic number from the CPUID
level dependency table.

Signed-off-by: Dave Hansen <[email protected]>
Reviewed-by: Zhao Liu <[email protected]>
Link: https://lore.kernel.org/all/20241213205037.43C57CDE%40davehans-spike.ostc.intel.com

Author: hansendc

arch/x86/include/asm/cpuid.h

@@ -23,8 +23,10 @@ enum cpuid_regs_idx {
 
 #define CPUID_MWAIT_LEAF	0x5
 #define CPUID_DCA_LEAF		0x9
+#define XSTATE_CPUID		0x0d
 #define CPUID_TSC_LEAF		0x15
 #define CPUID_FREQ_LEAF		0x16
+#define TILE_CPUID		0x1d
 
 #ifdef CONFIG_X86_32
 bool have_cpuid_p(void);

arch/x86/include/asm/fpu/xstate.h

@@ -12,10 +12,6 @@
 /* Bit 63 of XCR0 is reserved for future expansion */
 #define XFEATURE_MASK_EXTEND	(~(XFEATURE_MASK_FPSSE | (1ULL << 63)))
 
-#define XSTATE_CPUID		0x0000000d
-
-#define TILE_CPUID		0x0000001d
-
 #define FXSAVE_SIZE	512
 
 #define XSAVE_HDR_SIZE	    64

arch/x86/kernel/cpu/common.c

@@ -639,7 +639,7 @@ static const struct cpuid_dependent_feature
 cpuid_dependent_features[] = {
 	{ X86_FEATURE_MWAIT,		CPUID_MWAIT_LEAF },
 	{ X86_FEATURE_DCA,		CPUID_DCA_LEAF },
-	{ X86_FEATURE_XSAVE,		0x0000000d },
+	{ X86_FEATURE_XSAVE,		XSTATE_CPUID },
 	{ 0, 0 }
 };
 

arch/x86/kernel/fpu/xstate.c

@@ -20,6 +20,7 @@
 #include <asm/fpu/signal.h>
 #include <asm/fpu/xcr.h>
 
+#include <asm/cpuid.h>
 #include <asm/tlbflush.h>
 #include <asm/prctl.h>
 #include <asm/elf.h>