1 /* 2 * AMD Memory Encryption Support 3 * 4 * Copyright (C) 2016 Advanced Micro Devices, Inc. 5 * 6 * Author: Tom Lendacky <thomas.lendacky@amd.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #ifndef __MEM_ENCRYPT_H__ 14 #define __MEM_ENCRYPT_H__ 15 16 #ifndef __ASSEMBLY__ 17 18 #ifdef CONFIG_ARCH_HAS_MEM_ENCRYPT 19 20 #include <asm/mem_encrypt.h> 21 22 #else /* !CONFIG_ARCH_HAS_MEM_ENCRYPT */ 23 24 #define sme_me_mask 0ULL 25 26 static inline bool sme_active(void) { return false; } 27 static inline bool sev_active(void) { return false; } 28 29 #endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */ 30 31 static inline bool mem_encrypt_active(void) 32 { 33 return sme_me_mask; 34 } 35 36 static inline u64 sme_get_me_mask(void) 37 { 38 return sme_me_mask; 39 } 40 41 #ifdef CONFIG_AMD_MEM_ENCRYPT 42 /* 43 * The __sme_set() and __sme_clr() macros are useful for adding or removing 44 * the encryption mask from a value (e.g. when dealing with pagetable 45 * entries). 46 */ 47 #define __sme_set(x) ((x) | sme_me_mask) 48 #define __sme_clr(x) ((x) & ~sme_me_mask) 49 #else 50 #define __sme_set(x) (x) 51 #define __sme_clr(x) (x) 52 #endif 53 54 #endif /* __ASSEMBLY__ */ 55 56 #endif /* __MEM_ENCRYPT_H__ */ 57