UEFI EDK2框架学习（三）——protocol

一、Protocol协议

• 搜索支持特定Protocol的设备，获取其Handle

gBS->LocateHandleBuffer

• 将内存中的Driver绑定到给定的ControllerHandle

gBS->OpenProtocol

二、代码实现

Protocol.c

#include <Uefi.h>
#include <Library/UefiLib.h>
#include <Library/UefiBootServicesTableLib.h>EFI_STATUS
EFIAPI
UefiMain(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE *SystemTable
) {EFI_STATUS Status = EFI_SUCCESS;UINTN NoHandles = 0;EFI_HANDLE *Buffer = NULL;Status = gBS->LocateHandleBuffer(ByProtocol,&gEfiGraphicsOutputProtocolGuid,NULL,&NoHandles,&Buffer);Print(L"Status = %d", Status);if (EFI_ERROR(Status)) {Print(L"Failed to LocateHandleBuffer. \n");return Status;}Print(L"Hello, Protocol\n");EFI_GRAPHICS_OUTPUT_PROTOCOL *Gop;Status = gBS->OpenProtocol(Buffer[0],&gEfiGraphicsOutputProtocolGuid,(VOID**)&Gop,ImageHandle,NULL,EFI_OPEN_PROTOCOL_GET_PROTOCOL);Print(L"Status = %d", Status);if (EFI_ERROR(Status)) {Print(L"Failed to OpenProtocol. \n");return Status;}return Status;
}

Protocol.inf

[Defines]INF_VERSION = 0x00010006BASE_NAME = ProtocolFILE_GUID = 767c2824-dbe2-4a8f-b2f5-8a10f23e7853MODULE_TYPE = UEFI_APPLICATIONVERSION_STRING = 0.1ENTRY_POINT = UefiMain[Sources]HelloWorld.c[Packages]MdePkg/MdePkg.dec[LibraryClasses]UefiApplicationEntryPointUefiLib

ProtocolPkg.dsc

[Defines]PLATFORM_NAME = ProtocolPkgPLATFORM_GUID = 767c2824-dbe2-4a8f-b2f5-8a10f23e7853PLATFORM_VERSION = 0.1DSC_SPECIFICATION = 0x00010005SUPPORTED_ARCHITECTURES = X64BUILD_TARGETS = DEBUG|RELEASEOUTPUT_DIRECTORY = ProtocolPkg/Build[LibraryClasses]UefiLib|MdePkg/Library/UefiLib/UefiLib.infUefiApplicationEntryPoint|MdePkg/Library/UefiApplicationEntryPoint/UefiApplicationEntryPoint.infPrintLib|MdePkg/Library/BasePrintLib/BasePrintLib.infPcdLib|MdePkg/Library/BasePcdLibNull/BasePcdLibNull.infMemoryAllocationLib|MdePkg/Library/UefiMemoryAllocationLib/UefiMemoryAllocationLib.infDebugLib|MdePkg/Library/UefiDebugLibConOut/UefiDebugLibConOut.infBaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.infBaseLib|MdePkg/Library/BaseLib/BaseLib.infUefiBootServicesTableLib|MdePkg/Library/UefiBootServicesTableLib/UefiBootServicesTableLib.infDevicePathLib|MdePkg/Library/UefiDevicePathLib/UefiDevicePathLib.infUefiRuntimeServicesTableLib|MdePkg/Library/UefiRuntimeServicesTableLib/UefiRuntimeServicesTableLib.infRegisterFilterLib|MdePkg/Library/RegisterFilterLibNull/RegisterFilterLibNull.infDebugPrintErrorLevelLib|MdePkg/Library/BaseDebugPrintErrorLevelLib/BaseDebugPrintErrorLevelLib.inf
[Components]ProtocolPkg/Protocol.inf

三、参考文献

UEFI——UEFI 基础服务_installprotocolinterface-CSDN博客

UEFI——protocol服务详解_uefi protocol-CSDN博客