projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 3aa8dc6c LQ |
1 | /** @file\r |
| 2 | RDRAND Support Routines for GCC environment.\r | |
| 3 | \r | |
| 4 | Copyright (c) 2013, Intel Corporation. All rights reserved.<BR>\r | |
| 5 | This program and the accompanying materials\r | |
| 6 | are licensed and made available under the terms and conditions of the BSD License\r | |
| 7 | which accompanies this distribution. The full text of the license may be found at\r | |
| 8 | http://opensource.org/licenses/bsd-license.php\r | |
| 9 | \r | |
| 10 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
| 11 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
| 12 | \r | |
| 13 | **/\r | |
| 14 | \r | |
| 15 | /**\r | |
| 16 | Generates a 16-bit random number through RDRAND instruction.\r | |
| 17 | \r | |
| 18 | @param[out] Rand Buffer pointer to store the random result.\r | |
| 19 | \r | |
| 20 | @retval TRUE RDRAND call was successful.\r | |
| 21 | @retval FALSE Failed attempts to call RDRAND.\r | |
| 22 | \r | |
| 23 | **/\r | |
| 24 | BOOLEAN\r | |
| 25 | EFIAPI\r | |
| 26 | RdRand16Step (\r | |
| 27 | OUT UINT16 *Rand\r | |
| 28 | )\r | |
| 29 | {\r | |
| 30 | UINT8 Carry;\r | |
| 31 | \r | |
| 32 | //\r | |
| 33 | // Uses byte code for RDRAND instruction,\r | |
| 34 | // in case that GCC version has no direct support on RDRAND assembly.\r | |
| 35 | //\r | |
| 36 | __asm__ __volatile__ (\r | |
| 37 | ".byte 0x66; .byte 0x0f; .byte 0xc7; .byte 0xf0; setc %1"\r | |
| 38 | :"=a" (*Rand),\r | |
| 39 | "=qm" (Carry)\r | |
| 40 | ); \r | |
| 41 | \r | |
| 42 | return (BOOLEAN) Carry;\r | |
| 43 | }\r | |
| 44 | \r | |
| 45 | /**\r | |
| 46 | Generates a 32-bit random number through RDRAND instruction.\r | |
| 47 | \r | |
| 48 | @param[out] Rand Buffer pointer to store the random result.\r | |
| 49 | \r | |
| 50 | @retval TRUE RDRAND call was successful.\r | |
| 51 | @retval FALSE Failed attempts to call RDRAND.\r | |
| 52 | \r | |
| 53 | **/\r | |
| 54 | BOOLEAN\r | |
| 55 | EFIAPI\r | |
| 56 | RdRand32Step (\r | |
| 57 | OUT UINT32 *Rand\r | |
| 58 | )\r | |
| 59 | {\r | |
| 60 | UINT8 Carry;\r | |
| 61 | \r | |
| 62 | __asm__ __volatile__ (\r | |
| 63 | ".byte 0x0f; .byte 0xc7; .byte 0xf0; setc %1"\r | |
| 64 | :"=a" (*Rand), \r | |
| 65 | "=qm" (Carry)\r | |
| 66 | );\r | |
| 67 | \r | |
| 68 | return (BOOLEAN) Carry;\r | |
| 69 | }\r | |
| 70 | \r | |
| 71 | /**\r | |
| 72 | Generates a 64-bit random number through RDRAND instruction.\r | |
| 73 | \r | |
| 74 | @param[out] Rand Buffer pointer to store the random result.\r | |
| 75 | \r | |
| 76 | @retval TRUE RDRAND call was successful.\r | |
| 77 | @retval FALSE Failed attempts to call RDRAND.\r | |
| 78 | \r | |
| 79 | **/\r | |
| 80 | BOOLEAN\r | |
| 81 | EFIAPI\r | |
| 82 | RdRand64Step (\r | |
| 83 | OUT UINT64 *Rand\r | |
| 84 | )\r | |
| 85 | {\r | |
| 86 | UINT8 Carry;\r | |
| 87 | \r | |
| 88 | __asm__ __volatile__ (\r | |
| 89 | ".byte 0x48; .byte 0x0f; .byte 0xc7; .byte 0xf0; setc %1"\r | |
| 90 | :"=a" (*Rand), \r | |
| 91 | "=qm" (Carry)\r | |
| 92 | );\r | |
| 93 | \r | |
| 94 | return (BOOLEAN) Carry;\r | |
| 95 | }\r |