Tested with the "bootorder" fw_cfg file. Example contents (leading space added and line terminators transcribed for readability):
/pci@i0cf8/ide@1,1/drive@0/disk@0<LF> /pci@i0cf8/ide@1,1/drive@1/disk@0<LF> /pci@i0cf8/ethernet@3/ethernet-phy@0<NUL> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <[email protected]> --- OvmfPkg/Include/Library/QemuFwCfgLib.h | 21 +++++++++++ OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c | 53 +++++++++++++++++++++++++++ 2 files changed, 74 insertions(+), 0 deletions(-) diff --git a/OvmfPkg/Include/Library/QemuFwCfgLib.h b/OvmfPkg/Include/Library/QemuFwCfgLib.h index 5a3db7e..7e02f39 100644 --- a/OvmfPkg/Include/Library/QemuFwCfgLib.h +++ b/OvmfPkg/Include/Library/QemuFwCfgLib.h @@ -41,6 +41,7 @@ typedef enum { QemuFwCfgItemKernelSetupAddress = 0x0016, QemuFwCfgItemKernelSetupSize = 0x0017, QemuFwCfgItemKernelSetupData = 0x0018, + QemuFwCfgItemFileDir = 0x0019, QemuFwCfgItemX86AcpiTables = 0x8000, QemuFwCfgItemX86SmbiosTables = 0x8001, @@ -153,5 +154,25 @@ QemuFwCfgRead64 ( ); +/** + Find the configuration item corresponding to the firmware configuration file. + + @param[in] Name - Name of file to look up. + @param[out] Item - Configuration item corresponding to the file, to be passed + to QemuFwCfgSelectItem (). + @param[out] Size - Number of bytes in the file. + + @return RETURN_SUCCESS if file is found, + RETURN_NOT_FOUND if file is not found, + RETURN_UNSUPPORTED if firmware configuration is unavailable. + +**/ +RETURN_STATUS +EFIAPI +QemuFwCfgFindFile ( + IN CONST CHAR8 Name[56], + OUT FIRMWARE_CONFIG_ITEM *Item, + OUT UINT32 *Size + ); #endif diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c index b94dc67..95dd2ea 100644 --- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c @@ -244,3 +244,56 @@ QemuFwCfgInitialize ( DEBUG ((EFI_D_INFO, "QemuFwCfg interface is supported.\n")); return RETURN_SUCCESS; } + + +/** + Find the configuration item corresponding to the firmware configuration file. + + @param[in] Name - Name of file to look up. + @param[out] Item - Configuration item corresponding to the file, to be passed + to QemuFwCfgSelectItem (). + @param[out] Size - Number of bytes in the file. + + @return RETURN_SUCCESS if file is found, + RETURN_NOT_FOUND if file is not found, + RETURN_UNSUPPORTED if firmware configuration is unavailable. + +**/ +RETURN_STATUS +EFIAPI +QemuFwCfgFindFile ( + IN CONST CHAR8 Name[56], + OUT FIRMWARE_CONFIG_ITEM *Item, + OUT UINT32 *Size + ) +{ + UINT32 Count; + UINT32 Idx; + + if (!mQemuFwCfgSupported) { + return RETURN_UNSUPPORTED; + } + + QemuFwCfgSelectItem (QemuFwCfgItemFileDir); + Count = SwapBytes32 (QemuFwCfgRead32 ()); + + for (Idx = 0; Idx < Count; ++Idx) { + UINT32 FSizeBE; + UINT16 FSelectBE; + UINT16 FReservedBE; + CHAR8 FName[56]; + + FSizeBE = QemuFwCfgRead32 (); + FSelectBE = QemuFwCfgRead16 (); + FReservedBE = QemuFwCfgRead16 (); + InternalQemuFwCfgReadBytes (sizeof (FName), FName); + + if (AsciiStrCmp (Name, FName) == 0) { + *Item = SwapBytes16 (FSelectBE); + *Size = SwapBytes32 (FSizeBE); + return RETURN_SUCCESS; + } + } + + return RETURN_NOT_FOUND; +} -- 1.7.1 ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ edk2-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/edk2-devel
