/** @file RISC-V Flattened Device Tree DXE module The Linux booting protocol on RISC-V requires the id of the booting hart to be passed as a0. Therefore the EFISTUB needs to get this information. Because it runs in S-Mode, it cannot get this information from mhartid. Instead we insert the id into the device tree, that the EFIFSTUB can read from the config table. Copyright (c) 2021, Hewlett Packard Enterprise Development LP. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent **/ #include #include #include #include #include #include /** Fix up the device tree with booting hartid for the kernel @param DtbBlob The device tree. Is extended to fit the hart id. @retval EFI_SUCCESS The device tree was success fixed up with the hart id. @retval EFI_OUT_OF_RESOURCES There is not enough memory available to complete the operation. **/ EFI_STATUS EFIAPI FixDtb ( IN OUT VOID *DtbBlob, IN UINTN BootingHartId ) { fdt32_t Size; UINT32 ChosenOffset, Err; DEBUG ((DEBUG_INFO, "Fixing up device tree with boot hart id: %d\n", BootingHartId)); Size = fdt_totalsize(DtbBlob); Err = fdt_open_into(DtbBlob, DtbBlob, Size + 32); if (Err < 0) { DEBUG ((DEBUG_ERROR, "Device Tree can't be expanded to accommodate new node\n", __FUNCTION__)); return EFI_OUT_OF_RESOURCES; } ChosenOffset = fdt_path_offset(DtbBlob, "/chosen"); fdt_setprop_u32(DtbBlob, ChosenOffset, "boot-hartid", BootingHartId); return EFI_SUCCESS; } /** Install the FDT passed in HOB into EFI system configuration table. @retval EFI_SUCCESS Successfully installed fixed up FDT in config table. @retval EFI_NOT_FOUND Did not find FDT HOB. @retval EFI_OUT_OF_RESOURCES There is not enough memory available to complete the operation. **/ EFI_STATUS EFIAPI InstallFdtFromHob (VOID) { EFI_STATUS Status; EFI_HOB_GUID_TYPE *GuidHob; VOID *DataInHob; UINTN DataSize; GuidHob = GetFirstGuidHob (&gFdtHobGuid); if (GuidHob == NULL) { DEBUG ((DEBUG_ERROR, "Failed to find RISC-V DTB Hob\n", __FUNCTION__)); return EFI_NOT_FOUND; } DataInHob = (VOID *) *((UINTN *) GET_GUID_HOB_DATA (GuidHob)); DataSize = GET_GUID_HOB_DATA_SIZE (GuidHob); Status = FixDtb (DataInHob, PcdGet32(PcdBootHartId)); if (EFI_ERROR (Status)) { return Status; } Status = gBS->InstallConfigurationTable (&gFdtTableGuid, DataInHob); if (EFI_ERROR (Status)) { DEBUG ((DEBUG_ERROR, "%a: failed to install FDT configuration table\n", __FUNCTION__)); } return Status; } /** Install the FDT from the HOB into the EFI system configuration table. @param ImageHandle Image handle of this driver. @param SystemTable Pointer to the System Table. @retval EFI_SUCCESS FDT successfully installed into config table. @retval EFI_NOT_FOUND Did not find FDT HOB. @retval EFI_OUT_OF_RESOURCES There is not enough memory available to complete the operation. **/ EFI_STATUS EFIAPI InstallFdt ( IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable ) { EFI_STATUS Status; Status = InstallFdtFromHob (); return Status; }