1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_FPU_XCR_H 3 #define _ASM_X86_FPU_XCR_H 4 5 #define XCR_XFEATURE_ENABLED_MASK 0x00000000 6 #define XCR_XFEATURE_IN_USE_MASK 0x00000001 7 8 static __always_inline u64 xgetbv(u32 index) 9 { 10 u32 eax, edx; 11 12 asm volatile("xgetbv" : "=a" (eax), "=d" (edx) : "c" (index)); 13 return eax + ((u64)edx << 32); 14 } 15 16 static inline void xsetbv(u32 index, u64 value) 17 { 18 u32 eax = value; 19 u32 edx = value >> 32; 20 21 asm volatile("xsetbv" :: "a" (eax), "d" (edx), "c" (index)); 22 } 23 24 /* 25 * Return a mask of xfeatures which are currently being tracked 26 * by the processor as being in the initial configuration. 27 * 28 * Callers should check X86_FEATURE_XGETBV1. 29 */ 30 static __always_inline u64 xfeatures_in_use(void) 31 { 32 return xgetbv(XCR_XFEATURE_IN_USE_MASK); 33 } 34 35 #endif /* _ASM_X86_FPU_XCR_H */ 36