projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 2b1a5b8c NOL |
1 | /*/@file\r |
| 2 | Qemu fw-cfg wrappers for hardware info parsing.\r | |
| 3 | Provides an alternative to parse hardware information from a fw-cfg\r | |
| 4 | file without relying on dynamic memory allocations.\r | |
| 5 | \r | |
| 6 | Copyright 2021 - 2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.\r | |
| 7 | SPDX-License-Identifier: BSD-2-Clause-Patent\r | |
| 8 | \r | |
| 9 | **/\r | |
| 10 | \r | |
| 11 | #include <Library/DebugLib.h>\r | |
| 12 | #include <Library/QemuFwCfgLib.h>\r | |
| 13 | \r | |
| 14 | #include <Library/HardwareInfoLib.h>\r | |
| 15 | \r | |
| 16 | /**\r | |
| 17 | Update an optional pointer value if possible\r | |
| 18 | \r | |
| 19 | @param[out] DataSize Pointer to variable to be updated\r | |
| 20 | @param[in] Value Value to set the pointed variable to.\r | |
| 21 | **/\r | |
| 22 | STATIC\r | |
| 23 | VOID\r | |
| 24 | UpdateDataSize (\r | |
| 25 | OUT UINTN *DataSize,\r | |
| 26 | IN UINTN Value\r | |
| 27 | )\r | |
| 28 | {\r | |
| 29 | if (DataSize == NULL) {\r | |
| 30 | return;\r | |
| 31 | }\r | |
| 32 | \r | |
| 33 | *DataSize = Value;\r | |
| 34 | }\r | |
| 35 | \r | |
| 36 | EFI_STATUS\r | |
| 37 | QemuFwCfgReadNextHardwareInfoByType (\r | |
| 38 | IN HARDWARE_INFO_TYPE Type,\r | |
| 39 | IN UINTN TypeSize,\r | |
| 40 | IN UINTN TotalFileSize,\r | |
| 41 | OUT VOID *Data,\r | |
| 42 | OUT UINTN *DataSize OPTIONAL,\r | |
| 43 | IN OUT UINTN *ReadIndex\r | |
| 44 | )\r | |
| 45 | {\r | |
| 46 | HARDWARE_INFO_HEADER Header;\r | |
| 47 | \r | |
| 48 | if ((Data == NULL) ||\r | |
| 49 | (ReadIndex == NULL) ||\r | |
| 50 | (TypeSize == 0) ||\r | |
| 51 | (Type == HardwareInfoTypeUndefined) ||\r | |
| 52 | (TotalFileSize == 0))\r | |
| 53 | {\r | |
| 54 | return EFI_INVALID_PARAMETER;\r | |
| 55 | }\r | |
| 56 | \r | |
| 57 | UpdateDataSize (DataSize, 0);\r | |
| 58 | \r | |
| 59 | while (*ReadIndex < TotalFileSize) {\r | |
| 60 | QemuFwCfgReadBytes (sizeof (Header), &Header);\r | |
| 61 | *ReadIndex += sizeof (Header);\r | |
| 62 | \r | |
| 63 | if ((Header.Size > MAX_UINTN) || (((UINT64)*ReadIndex + Header.Size) > TotalFileSize)) {\r | |
| 64 | *ReadIndex = TotalFileSize;\r | |
| 65 | return EFI_ABORTED;\r | |
| 66 | }\r | |
| 67 | \r | |
| 68 | if ((Header.Type.Value == Type) && (Header.Size <= TypeSize)) {\r | |
| 69 | QemuFwCfgReadBytes ((UINTN)Header.Size, Data);\r | |
| 70 | \r | |
| 71 | *ReadIndex += (UINTN)Header.Size;\r | |
| 72 | UpdateDataSize (DataSize, (UINTN)Header.Size);\r | |
| 73 | \r | |
| 74 | return EFI_SUCCESS;\r | |
| 75 | }\r | |
| 76 | \r | |
| 77 | //\r | |
| 78 | // Skip the bytes corresponding to the next element as it is\r | |
| 79 | // not of the expected type and/or size. The TotalFileSize\r | |
| 80 | // and individual elements sizes should match so the size\r | |
| 81 | // check is skipped.\r | |
| 82 | //\r | |
| 83 | QemuFwCfgSkipBytes ((UINTN)Header.Size);\r | |
| 84 | *ReadIndex += (UINTN)Header.Size;\r | |
| 85 | }\r | |
| 86 | \r | |
| 87 | return EFI_END_OF_FILE;\r | |
| 88 | }\r |