1 /** @file 2 Base Library CPU Functions for EBC 3 4 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR> 5 This program and the accompanying materials 6 are licensed and made available under the terms and conditions of the BSD License 7 which accompanies this distribution. The full text of the license may be found at 8 http://opensource.org/licenses/bsd-license.php. 9 10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 12 13 **/ 14 15 #include "BaseLibInternals.h" 16 17 extern 18 UINT64 19 _break ( 20 CHAR8 BreakCode 21 ); 22 23 /** 24 Generates a breakpoint on the CPU. 25 26 Generates a breakpoint on the CPU. The breakpoint must be implemented such 27 that code can resume normal execution after the breakpoint. 28 29 **/ 30 VOID 31 EFIAPI CpuBreakpoint(VOID)32CpuBreakpoint ( 33 VOID 34 ) 35 { 36 _break (3); 37 } 38 39 /** 40 Used to serialize load and store operations. 41 42 All loads and stores that proceed calls to this function are guaranteed to be 43 globally visible when this function returns. 44 45 **/ 46 VOID 47 EFIAPI MemoryFence(VOID)48MemoryFence ( 49 VOID 50 ) 51 { 52 } 53 54 /** 55 Disables CPU interrupts. 56 57 **/ 58 VOID 59 EFIAPI DisableInterrupts(VOID)60DisableInterrupts ( 61 VOID 62 ) 63 { 64 ASSERT (FALSE); 65 } 66 67 /** 68 Enables CPU interrupts. 69 70 **/ 71 VOID 72 EFIAPI EnableInterrupts(VOID)73EnableInterrupts ( 74 VOID 75 ) 76 { 77 ASSERT (FALSE); 78 } 79 80 /** 81 Retrieves the current CPU interrupt state. 82 83 Returns TRUE means interrupts are currently enabled. Otherwise, 84 returns FALSE. 85 86 @retval TRUE CPU interrupts are enabled. 87 @retval FALSE CPU interrupts are disabled. 88 89 **/ 90 BOOLEAN 91 EFIAPI GetInterruptState(VOID)92GetInterruptState ( 93 VOID 94 ) 95 { 96 ASSERT (FALSE); 97 return FALSE; 98 } 99 100 /** 101 Enables CPU interrupts for the smallest window required to capture any 102 pending interrupts. 103 104 **/ 105 VOID 106 EFIAPI EnableDisableInterrupts(VOID)107EnableDisableInterrupts ( 108 VOID 109 ) 110 { 111 EnableInterrupts (); 112 DisableInterrupts (); 113 } 114 115 /** 116 Requests CPU to pause for a short period of time. 117 118 Requests CPU to pause for a short period of time. Typically used in MP 119 systems to prevent memory starvation while waiting for a spin lock. 120 121 **/ 122 VOID 123 EFIAPI CpuPause(VOID)124CpuPause ( 125 VOID 126 ) 127 { 128 } 129 130