2 * AMD Memory Encryption Support
4 * Copyright (C) 2016 Advanced Micro Devices, Inc.
6 * Author: Tom Lendacky <thomas.lendacky@amd.com>
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.
13 #ifndef __X86_MEM_ENCRYPT_H__
14 #define __X86_MEM_ENCRYPT_H__
18 #include <linux/init.h>
20 #ifdef CONFIG_AMD_MEM_ENCRYPT
22 extern unsigned long sme_me_mask;
24 void __init sme_early_init(void);
26 void __init sme_encrypt_kernel(void);
27 void __init sme_enable(void);
29 #else /* !CONFIG_AMD_MEM_ENCRYPT */
31 #define sme_me_mask 0UL
33 static inline void __init sme_early_init(void) { }
35 static inline void __init sme_encrypt_kernel(void) { }
36 static inline void __init sme_enable(void) { }
38 #endif /* CONFIG_AMD_MEM_ENCRYPT */
41 * The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
42 * writing to or comparing values from the cr3 register. Having the
43 * encryption mask set in cr3 enables the PGD entry to be encrypted and
44 * avoid special case handling of PGD allocations.
46 #define __sme_pa(x) (__pa(x) | sme_me_mask)
47 #define __sme_pa_nodebug(x) (__pa_nodebug(x) | sme_me_mask)
49 #endif /* __ASSEMBLY__ */
51 #endif /* __X86_MEM_ENCRYPT_H__ */