projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| ebd04fc2 | 1 | /** @file\r |
| 2 | GCC inline implementation of BaseLib processor specific functions.\r | |
| 3 | \r | |
| bb817c56 HT |
4 | Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>\r |
| 5 | Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>\r | |
| 6 | This program and the accompanying materials\r | |
| ebd04fc2 | 7 | are licensed and made available under the terms and conditions of the BSD License\r |
| 8 | which accompanies this distribution. The full text of the license may be found at\r | |
| 9 | http://opensource.org/licenses/bsd-license.php\r | |
| 10 | \r | |
| 11 | THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
| 12 | WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
| 13 | \r | |
| 14 | **/\r | |
| 15 | \r | |
| 16 | #include "BaseLibInternals.h"\r | |
| 17 | \r | |
| 18 | /**\r | |
| 19 | Requests CPU to pause for a short period of time.\r | |
| 20 | \r | |
| 21 | Requests CPU to pause for a short period of time. Typically used in MP\r | |
| 22 | systems to prevent memory starvation while waiting for a spin lock.\r | |
| 23 | \r | |
| 24 | **/\r | |
| 25 | VOID\r | |
| 26 | EFIAPI\r | |
| 27 | CpuPause (\r | |
| 28 | VOID\r | |
| 29 | )\r | |
| 30 | {\r | |
| 31 | __asm__ __volatile__ (\r | |
| 32 | "nop\n\t"\r | |
| 33 | "nop\n\t"\r | |
| 34 | "nop\n\t"\r | |
| 35 | "nop\n\t"\r | |
| 36 | "nop\n\t"\r | |
| 37 | );\r | |
| 38 | }\r | |
| 39 | \r | |
| ea6898b9 | 40 | /**\r |
| 41 | Transfers control to a function starting with a new stack.\r | |
| 42 | \r | |
| 43 | This internal worker function transfers control to the function\r | |
| 44 | specified by EntryPoint using the new stack specified by NewStack\r | |
| 45 | and passing in the parameters specified by Context1 and Context2.\r | |
| 46 | Context1 and Context2 are optional and may be NULL.\r | |
| 47 | The function EntryPoint must never return.\r | |
| 48 | \r | |
| 49 | @param EntryPoint The pointer to the function to enter.\r | |
| 50 | @param Context1 The first parameter to pass in.\r | |
| 51 | @param Context2 The second Parameter to pass in\r | |
| 52 | @param NewStack The new Location of the stack\r | |
| 53 | \r | |
| 54 | **/\r | |
| ebd04fc2 | 55 | VOID\r |
| 56 | EFIAPI\r | |
| 57 | InternalSwitchStackAsm (\r | |
| 58 | SWITCH_STACK_ENTRY_POINT EntryPoint,\r | |
| ea6898b9 | 59 | VOID *Context1,\r |
| ebd04fc2 | 60 | VOID *Context2,\r |
| 61 | VOID *NewStack\r | |
| 62 | )\r | |
| 63 | {\r | |
| 64 | __asm__ __volatile__ (\r | |
| 65 | "mov lr, %0\n\t"\r | |
| 66 | "mov sp, %3\n\t"\r | |
| 67 | "mov %r0, %1\n\t"\r | |
| 68 | "mov %r1, %2\n\t"\r | |
| 69 | "bx lr\n\t"\r | |
| 70 | : /* no output operand */\r | |
| 71 | : "r" (EntryPoint),\r | |
| ea6898b9 | 72 | "r" (Context1),\r |
| ebd04fc2 | 73 | "r" (Context2),\r |
| 74 | "r" (NewStack)\r | |
| 75 | );\r | |
| 76 | }\r |