Added the PEI stage library for QemuFwCfgMmioLib, which uses the FDT to find the fw_cfg and parse it.
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4755 Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org> Cc: Jiewen Yao <jiewen....@intel.com> Cc: Gerd Hoffmann <kra...@redhat.com> Co-authored-by: Xianglai Li <lixiang...@loongson.cn> Signed-off-by: Chao Li <lic...@loongson.cn> --- .../Library/QemuFwCfgLib/QemuFwCfgMmioPei.c | 175 ++++++++++++++++++ .../QemuFwCfgLib/QemuFwCfgMmioPeiLib.inf | 48 +++++ 2 files changed, 223 insertions(+) create mode 100644 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c create mode 100644 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPeiLib.inf diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c new file mode 100644 index 0000000000..200d91b0f4 --- /dev/null +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c @@ -0,0 +1,175 @@ +/** @file + + Stateful and implicitly initialized fw_cfg library implementation. + + Copyright (C) 2013 - 2014, Red Hat, Inc. + Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR> + (C) Copyright 2021 Hewlett Packard Enterprise Development LP<BR> + Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR> + + SPDX-License-Identifier: BSD-2-Clause-Patent +**/ + +#include <Uefi.h> + +#include <Library/BaseLib.h> +#include <Library/DebugLib.h> +#include <Library/QemuFwCfgLib.h> + +#include <libfdt.h> + +#include "QemuFwCfgLibMmioInternal.h" + +UINTN mFwCfgSelectorAddress; +UINTN mFwCfgDataAddress; +UINTN mFwCfgDmaAddress; + +// +// These correspond to the implementation we detect at runtime. +// +READ_BYTES_FUNCTION *InternalQemuFwCfgReadBytes = MmioReadBytes; +WRITE_BYTES_FUNCTION *InternalQemuFwCfgWriteBytes = MmioWriteBytes; +SKIP_BYTES_FUNCTION *InternalQemuFwCfgSkipBytes = MmioSkipBytes; + +RETURN_STATUS +EFIAPI +QemuFwCfgInitialize ( + VOID + ) +{ + VOID *DeviceTreeBase; + INT32 Node; + INT32 Prev; + CONST CHAR8 *Type; + INT32 Len; + CONST UINT64 *Reg; + UINT64 FwCfgSelectorAddress; + UINT64 FwCfgSelectorSize; + UINT64 FwCfgDataAddress; + UINT64 FwCfgDataSize; + UINT64 FwCfgDmaAddress; + UINT64 FwCfgDmaSize; + + DeviceTreeBase = (VOID *)(UINTN)PcdGet64 (PcdDeviceTreeInitialBaseAddress); + ASSERT (DeviceTreeBase != NULL); + // + // Make sure we have a valid device tree blob + // + ASSERT (fdt_check_header (DeviceTreeBase) == 0); + + for (Prev = 0; ; Prev = Node) { + Node = fdt_next_node (DeviceTreeBase, Prev, NULL); + if (Node < 0) { + break; + } + + // + // Check for memory node + // + Type = fdt_getprop (DeviceTreeBase, Node, "compatible", &Len); + if ((Type) && + (AsciiStrnCmp (Type, "qemu,fw-cfg-mmio", Len) == 0)) + { + // + // Get the 'reg' property of this node. For now, we will assume + // two 8 byte quantities for base and size, respectively. + // + Reg = fdt_getprop (DeviceTreeBase, Node, "reg", &Len); + if ((Reg != 0) && (Len == (2 * sizeof (UINT64)))) { + FwCfgDataAddress = SwapBytes64 (Reg[0]); + FwCfgDataSize = 8; + FwCfgSelectorAddress = FwCfgDataAddress + FwCfgDataSize; + FwCfgSelectorSize = 2; + + // + // The following ASSERT()s express + // + // Address + Size - 1 <= MAX_UINTN + // + // for both registers, that is, that the last byte in each MMIO range is + // expressible as a MAX_UINTN. The form below is mathematically + // equivalent, and it also prevents any unsigned overflow before the + // comparison. + // + ASSERT (FwCfgSelectorAddress <= MAX_UINTN - FwCfgSelectorSize + 1); + ASSERT (FwCfgDataAddress <= MAX_UINTN - FwCfgDataSize + 1); + + + mFwCfgSelectorAddress = FwCfgSelectorAddress; + if (mFwCfgSelectorAddress) { + QemuBuildFwCfgSelectorHob (FwCfgSelectorAddress); + } + + mFwCfgDataAddress = FwCfgDataAddress; + if (mFwCfgDataAddress) { + QemuBuildFwCfgDataHob (FwCfgDataAddress); + } + + DEBUG (( + DEBUG_INFO, + "Found FwCfg @ 0x%Lx/0x%Lx\n", + FwCfgSelectorAddress, + FwCfgDataAddress + )); + + if (SwapBytes64 (Reg[1]) >= 0x18) { + FwCfgDmaAddress = FwCfgDataAddress + 0x10; + FwCfgDmaSize = 0x08; + + // + // See explanation above. + // + ASSERT (FwCfgDmaAddress <= MAX_UINTN - FwCfgDmaSize + 1); + + DEBUG ((DEBUG_INFO, "Found FwCfg DMA @ 0x%Lx\n", FwCfgDmaAddress)); + } else { + FwCfgDmaAddress = 0; + } + + if (QemuFwCfgIsAvailable ()) { + UINT32 Signature; + + QemuFwCfgSelectItem (QemuFwCfgItemSignature); + Signature = QemuFwCfgRead32 (); + if (Signature == SIGNATURE_32 ('Q', 'E', 'M', 'U')) { + // + // For DMA support, we require the DTB to advertise the register, and the + // feature bitmap (which we read without DMA) to confirm the feature. + // + if (FwCfgDmaAddress != 0) { + UINT32 Features; + + QemuFwCfgSelectItem (QemuFwCfgItemInterfaceVersion); + Features = QemuFwCfgRead32 (); + if ((Features & FW_CFG_F_DMA) != 0) { + mFwCfgDmaAddress = FwCfgDmaAddress; + if (mFwCfgDmaAddress == 0) { + QemuBuildFwCfgDmaHob (FwCfgDmaAddress); + } + InternalQemuFwCfgReadBytes = DmaReadBytes; + InternalQemuFwCfgWriteBytes = DmaWriteBytes; + InternalQemuFwCfgSkipBytes = DmaSkipBytes; + } + } + } else { + mFwCfgSelectorAddress = 0; + mFwCfgDataAddress = 0; + QemuBuildFwCfgSelectorHob (0x0); + QemuBuildFwCfgDataHob (0x0); + } + } + + break; + } else { + DEBUG (( + DEBUG_ERROR, + "%a: Failed to parse FDT QemuCfg node\n", + __func__ + )); + break; + } + } + } + + return RETURN_SUCCESS; +} diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPeiLib.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPeiLib.inf new file mode 100644 index 0000000000..1e08810a4c --- /dev/null +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPeiLib.inf @@ -0,0 +1,48 @@ +## @file +# +# Stateful, implicitly initialized fw_cfg library. +# +# Copyright (C) 2013 - 2014, Red Hat, Inc. +# Copyright (c) 2008 - 2012, Intel Corporation. All rights reserved.<BR> +# Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR> +# +# SPDX-License-Identifier: BSD-2-Clause-Patent +# +## + +[Defines] + INF_VERSION = 1.29 + BASE_NAME = QemuFwCfgPeiLib + FILE_GUID = CDF9A9D5-7422-4DCB-B41D-607151AD320B + MODULE_TYPE = BASE + VERSION_STRING = 1.0 + LIBRARY_CLASS = QemuFwCfgLib|PEIM + + CONSTRUCTOR = QemuFwCfgInitialize + +# +# The following information is for reference only and not required by the build +# tools. +# +# VALID_ARCHITECTURES = LOONGARCH64 +# + +[Sources] + QemuFwCfgLibMmio.c + QemuFwCfgMmioPei.c + +[Packages] + MdePkg/MdePkg.dec + OvmfPkg/OvmfPkg.dec + EmbeddedPkg/EmbeddedPkg.dec + +[LibraryClasses] + BaseLib + BaseMemoryLib + DebugLib + HobLib + IoLib + PcdLib + +[Pcd] + gUefiOvmfPkgTokenSpaceGuid.PcdDeviceTreeInitialBaseAddress -- 2.27.0 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. 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