1 /** @file 2 Implement EFI RealTimeClock runtime services via Xen shared info page 3 4 Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR> 5 6 This program and the accompanying materials 7 are licensed and made available under the terms and conditions of the BSD License 8 which accompanies this distribution. The full text of the license may be found at 9 http://opensource.org/licenses/bsd-license.php 10 11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 13 14 **/ 15 16 #include <Uefi.h> 17 #include <PiDxe.h> 18 #include <Library/BaseLib.h> 19 #include <Library/DebugLib.h> 20 21 /** 22 Converts Epoch seconds (elapsed since 1970 JANUARY 01, 00:00:00 UTC) to EFI_TIME 23 **/ 24 STATIC 25 VOID 26 EpochToEfiTime ( 27 IN UINTN EpochSeconds, 28 OUT EFI_TIME *Time 29 ) 30 { 31 UINTN a; 32 UINTN b; 33 UINTN c; 34 UINTN d; 35 UINTN g; 36 UINTN j; 37 UINTN m; 38 UINTN y; 39 UINTN da; 40 UINTN db; 41 UINTN dc; 42 UINTN dg; 43 UINTN hh; 44 UINTN mm; 45 UINTN ss; 46 UINTN J; 47 48 J = (EpochSeconds / 86400) + 2440588; 49 j = J + 32044; 50 g = j / 146097; 51 dg = j % 146097; 52 c = (((dg / 36524) + 1) * 3) / 4; 53 dc = dg - (c * 36524); 54 b = dc / 1461; 55 db = dc % 1461; 56 a = (((db / 365) + 1) * 3) / 4; 57 da = db - (a * 365); 58 y = (g * 400) + (c * 100) + (b * 4) + a; 59 m = (((da * 5) + 308) / 153) - 2; 60 d = da - (((m + 4) * 153) / 5) + 122; 61 62 Time->Year = y - 4800 + ((m + 2) / 12); 63 Time->Month = ((m + 2) % 12) + 1; 64 Time->Day = d + 1; 65 66 ss = EpochSeconds % 60; 67 a = (EpochSeconds - ss) / 60; 68 mm = a % 60; 69 b = (a - mm) / 60; 70 hh = b % 24; 71 72 Time->Hour = hh; 73 Time->Minute = mm; 74 Time->Second = ss; 75 Time->Nanosecond = 0; 76 77 } 78 79 /** 80 Returns the current time and date information, and the time-keeping capabilities 81 of the hardware platform. 82 83 @param Time A pointer to storage to receive a snapshot of the current time. 84 @param Capabilities An optional pointer to a buffer to receive the real time clock 85 device's capabilities. 86 87 @retval EFI_SUCCESS The operation completed successfully. 88 @retval EFI_INVALID_PARAMETER Time is NULL. 89 @retval EFI_DEVICE_ERROR The time could not be retrieved due to hardware error. 90 91 **/ 92 EFI_STATUS 93 EFIAPI 94 LibGetTime ( 95 OUT EFI_TIME *Time, 96 OUT EFI_TIME_CAPABILITIES *Capabilities 97 ) 98 { 99 ASSERT (Time != NULL); 100 101 // 102 // For now, there is nothing that we can do besides returning a bogus time, 103 // as Xen's timekeeping uses a shared info page which cannot be shared 104 // between UEFI and the OS 105 // 106 EpochToEfiTime(1421770011, Time); 107 108 return EFI_SUCCESS; 109 } 110 111 /** 112 Sets the current local time and date information. 113 114 @param Time A pointer to the current time. 115 116 @retval EFI_SUCCESS The operation completed successfully. 117 @retval EFI_INVALID_PARAMETER A time field is out of range. 118 @retval EFI_DEVICE_ERROR The time could not be set due due to hardware error. 119 120 **/ 121 EFI_STATUS 122 EFIAPI 123 LibSetTime ( 124 IN EFI_TIME *Time 125 ) 126 { 127 return EFI_DEVICE_ERROR; 128 } 129 130 131 /** 132 Returns the current wakeup alarm clock setting. 133 134 @param Enabled Indicates if the alarm is currently enabled or disabled. 135 @param Pending Indicates if the alarm signal is pending and requires acknowledgement. 136 @param Time The current alarm setting. 137 138 @retval EFI_SUCCESS The alarm settings were returned. 139 @retval EFI_INVALID_PARAMETER Any parameter is NULL. 140 @retval EFI_DEVICE_ERROR The wakeup time could not be retrieved due to a hardware error. 141 @retval EFI_UNSUPPORTED A wakeup timer is not supported on this platform. 142 143 **/ 144 EFI_STATUS 145 EFIAPI 146 LibGetWakeupTime ( 147 OUT BOOLEAN *Enabled, 148 OUT BOOLEAN *Pending, 149 OUT EFI_TIME *Time 150 ) 151 { 152 return EFI_UNSUPPORTED; 153 } 154 155 /** 156 Sets the system wakeup alarm clock time. 157 158 @param Enabled Enable or disable the wakeup alarm. 159 @param Time If Enable is TRUE, the time to set the wakeup alarm for. 160 161 @retval EFI_SUCCESS If Enable is TRUE, then the wakeup alarm was enabled. If 162 Enable is FALSE, then the wakeup alarm was disabled. 163 @retval EFI_INVALID_PARAMETER A time field is out of range. 164 @retval EFI_DEVICE_ERROR The wakeup time could not be set due to a hardware error. 165 @retval EFI_UNSUPPORTED A wakeup timer is not supported on this platform. 166 167 **/ 168 EFI_STATUS 169 EFIAPI 170 LibSetWakeupTime ( 171 IN BOOLEAN Enabled, 172 OUT EFI_TIME *Time 173 ) 174 { 175 return EFI_UNSUPPORTED; 176 } 177 178 /** 179 This is the declaration of an EFI image entry point. This can be the entry point to an application 180 written to this specification, an EFI boot service driver, or an EFI runtime driver. 181 182 @param ImageHandle Handle that identifies the loaded image. 183 @param SystemTable System Table for this image. 184 185 @retval EFI_SUCCESS The operation completed successfully. 186 187 **/ 188 EFI_STATUS 189 EFIAPI 190 LibRtcInitialize ( 191 IN EFI_HANDLE ImageHandle, 192 IN EFI_SYSTEM_TABLE *SystemTable 193 ) 194 { 195 return EFI_SUCCESS; 196 } 197
