OvmfPkg: Separate QemuFwCfgLibMmio.c into two files

Separate QemuFwCfgLibMmio.c into two files named QemuFwCfgLibMmio.c and
QemuFwCfgLibMmioDxe.c, added a new header named
QemuFwCfgLibMmioInternal.h for MMIO version.

Some DXE stage variables became non-static in this patch, they will be
restored to static in the next patch.

Build-tested only (with "ArmVirtQemu.dsc and RiscVVirtQemu.dsc").

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4755

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Cc: Sunil V L <sunilvl@ventanamicro.com>
Cc: Andrei Warkentin <andrei.warkentin@intel.com>
Signed-off-by: Chao Li <lichao@loongson.cn>

OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibMmioInternal.h

@@ -0,0 +1,173 @@
+/** @file
+  Internal interfaces specific to the QemuFwCfgLibMmio instances in OvmfPkg.
+
+  Copyright (C) 2016, Red Hat, Inc.
+  Copyright (C) 2017, Advanced Micro Devices. All rights reserved
+  Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef QEMU_FW_CFG_LIB_MMIO_INTERNAL_H_
+#define QEMU_FW_CFG_LIB_MMIO_INTERNAL_H_
+
+extern UINTN  mFwCfgSelectorAddress;
+extern UINTN  mFwCfgDataAddress;
+extern UINTN  mFwCfgDmaAddress;
+
+/**
+  Reads firmware configuration bytes into a buffer
+
+  @param[in] Size    Size in bytes to read
+  @param[in] Buffer  Buffer to store data into  (OPTIONAL if Size is 0)
+
+**/
+typedef
+VOID(EFIAPI READ_BYTES_FUNCTION)(
+  IN UINTN Size,
+  IN VOID  *Buffer OPTIONAL
+  );
+
+/**
+  Writes bytes from a buffer to firmware configuration
+
+  @param[in] Size    Size in bytes to write
+  @param[in] Buffer  Buffer to transfer data from (OPTIONAL if Size is 0)
+
+**/
+typedef
+VOID(EFIAPI WRITE_BYTES_FUNCTION)(
+  IN UINTN Size,
+  IN VOID  *Buffer OPTIONAL
+  );
+
+/**
+  Skips bytes in firmware configuration
+
+  @param[in] Size  Size in bytes to skip
+
+**/
+typedef
+VOID(EFIAPI SKIP_BYTES_FUNCTION)(
+  IN UINTN Size
+  );
+
+/**
+  Reads firmware configuration bytes into a buffer
+
+  @param[in] Size    Size in bytes to read
+  @param[in] Buffer  Buffer to store data into  (OPTIONAL if Size is 0)
+
+**/
+extern
+VOID (EFIAPI *InternalQemuFwCfgReadBytes)(
+  IN UINTN  Size,
+  IN VOID   *Buffer  OPTIONAL
+  );
+
+/**
+  Writes bytes from a buffer to firmware configuration
+
+  @param[in] Size    Size in bytes to write
+  @param[in] Buffer  Buffer to transfer data from (OPTIONAL if Size is 0)
+
+**/
+extern
+VOID (EFIAPI *InternalQemuFwCfgWriteBytes)(
+  IN UINTN  Size,
+  IN VOID   *Buffer  OPTIONAL
+  );
+
+/**
+  Skips bytes in firmware configuration
+
+  @param[in] Size  Size in bytes to skip
+
+**/
+extern
+VOID (EFIAPI *InternalQemuFwCfgSkipBytes)(
+  IN UINTN  Size
+  );
+
+/**
+  Slow READ_BYTES_FUNCTION.
+**/
+VOID
+EFIAPI
+MmioReadBytes (
+  IN UINTN  Size,
+  IN VOID   *Buffer OPTIONAL
+  );
+
+/**
+  Slow WRITE_BYTES_FUNCTION.
+**/
+VOID
+EFIAPI
+MmioWriteBytes (
+  IN UINTN  Size,
+  IN VOID   *Buffer OPTIONAL
+  );
+
+/**
+  Slow SKIP_BYTES_FUNCTION.
+**/
+VOID
+EFIAPI
+MmioSkipBytes (
+  IN UINTN  Size
+  );
+
+/**
+  Fast READ_BYTES_FUNCTION.
+**/
+VOID
+EFIAPI
+DmaReadBytes (
+  IN UINTN  Size,
+  IN VOID   *Buffer OPTIONAL
+  );
+
+/**
+  Fast WRITE_BYTES_FUNCTION.
+**/
+VOID
+EFIAPI
+DmaWriteBytes (
+  IN UINTN  Size,
+  IN VOID   *Buffer OPTIONAL
+  );
+
+/**
+  Fast SKIP_BYTES_FUNCTION.
+**/
+VOID
+EFIAPI
+DmaSkipBytes (
+  IN UINTN  Size
+  );
+
+/**
+  Transfer an array of bytes, or skip a number of bytes, using the DMA
+  interface.
+
+  @param[in]     Size     Size in bytes to transfer or skip.
+
+  @param[in,out] Buffer   Buffer to read data into or write data from. Ignored,
+                          and may be NULL, if Size is zero, or Control is
+                          FW_CFG_DMA_CTL_SKIP.
+
+  @param[in]     Control  One of the following:
+                          FW_CFG_DMA_CTL_WRITE - write to fw_cfg from Buffer.
+                          FW_CFG_DMA_CTL_READ  - read from fw_cfg into Buffer.
+                          FW_CFG_DMA_CTL_SKIP  - skip bytes in fw_cfg.
+**/
+VOID
+DmaTransferBytes (
+  IN     UINTN   Size,
+  IN OUT VOID    *Buffer OPTIONAL,
+  IN     UINT32  Control
+  );
+
+#endif