diff options
Diffstat (limited to 'OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c')
| -rw-r--r-- | OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c new file mode 100644 index 0000000000..b94dc67392 --- /dev/null +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c @@ -0,0 +1,246 @@ +/** @file
+
+ Copyright (c) 2011 - 2012, Intel Corporation. All rights reserved.<BR>
+
+ This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "Uefi.h"
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/QemuFwCfgLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+STATIC BOOLEAN mQemuFwCfgSupported = FALSE;
+
+
+/**
+ Reads an 8-bit I/O port fifo into a block of memory.
+
+ Reads the 8-bit I/O fifo port specified by Port.
+
+ The port is read Count times, and the read data is
+ stored in the provided Buffer.
+
+ This function must guarantee that all I/O read and write operations are
+ serialized.
+
+ If 8-bit I/O port operations are not supported, then ASSERT().
+
+ @param Port The I/O port to read.
+ @param Count The number of times to read I/O port.
+ @param Buffer The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+IoReadFifo8 (
+ IN UINTN Port,
+ IN UINTN Count,
+ OUT VOID *Buffer
+ );
+
+
+/**
+ Returns a boolean indicating if the firmware configuration interface
+ is available or not.
+
+ @retval TRUE The interface is available
+ @retval FALSE The interface is not available
+
+**/
+BOOLEAN
+EFIAPI
+QemuFwCfgIsAvailable (
+ VOID
+ )
+{
+ return mQemuFwCfgSupported;
+}
+
+
+/**
+ Selects a firmware configuration item for reading.
+
+ Following this call, any data read from this item will start from
+ the beginning of the configuration item's data.
+
+ @param[in] QemuFwCfgItem - Firmware Configuration item to read
+
+**/
+VOID
+EFIAPI
+QemuFwCfgSelectItem (
+ IN FIRMWARE_CONFIG_ITEM QemuFwCfgItem
+ )
+{
+ DEBUG ((EFI_D_INFO, "Select Item: 0x%x\n", (UINT16)(UINTN) QemuFwCfgItem));
+ IoWrite16 (0x510, (UINT16)(UINTN) QemuFwCfgItem);
+}
+
+
+/**
+ 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)
+
+**/
+VOID
+EFIAPI
+InternalQemuFwCfgReadBytes (
+ IN UINTN Size,
+ IN VOID *Buffer OPTIONAL
+ )
+{
+ IoReadFifo8 (0x511, Size, Buffer);
+}
+
+
+/**
+ Reads firmware configuration bytes into a buffer
+
+ If called multiple times, then the data read will
+ continue at the offset of the firmware configuration
+ item where the previous read ended.
+
+ @param[in] Size - Size in bytes to read
+ @param[in] Buffer - Buffer to store data into
+
+**/
+VOID
+EFIAPI
+QemuFwCfgReadBytes (
+ IN UINTN Size,
+ IN VOID *Buffer
+ )
+{
+ if (mQemuFwCfgSupported) {
+ InternalQemuFwCfgReadBytes (Size, Buffer);
+ } else {
+ ZeroMem (Buffer, Size);
+ }
+}
+
+
+/**
+ Reads a UINT8 firmware configuration value
+
+ @return Value of Firmware Configuration item read
+
+**/
+UINT8
+EFIAPI
+QemuFwCfgRead8 (
+ VOID
+ )
+{
+ UINT8 Result;
+
+ QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+ return Result;
+}
+
+
+/**
+ Reads a UINT16 firmware configuration value
+
+ @return Value of Firmware Configuration item read
+
+**/
+UINT16
+EFIAPI
+QemuFwCfgRead16 (
+ VOID
+ )
+{
+ UINT16 Result;
+
+ QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+ return Result;
+}
+
+
+/**
+ Reads a UINT32 firmware configuration value
+
+ @return Value of Firmware Configuration item read
+
+**/
+UINT32
+EFIAPI
+QemuFwCfgRead32 (
+ VOID
+ )
+{
+ UINT32 Result;
+
+ QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+ return Result;
+}
+
+
+/**
+ Reads a UINT64 firmware configuration value
+
+ @return Value of Firmware Configuration item read
+
+**/
+UINT64
+EFIAPI
+QemuFwCfgRead64 (
+ VOID
+ )
+{
+ UINT64 Result;
+
+ QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+ return Result;
+}
+
+
+RETURN_STATUS
+EFIAPI
+QemuFwCfgInitialize (
+ VOID
+ )
+{
+ UINT32 Signature;
+ UINT32 Revision;
+
+ //
+ // Enable the access routines while probing to see if it is supported.
+ //
+ mQemuFwCfgSupported = TRUE;
+
+ QemuFwCfgSelectItem (QemuFwCfgItemSignature);
+ Signature = QemuFwCfgRead32 ();
+ DEBUG ((EFI_D_INFO, "FW CFG Signature: 0x%x\n", Signature));
+ QemuFwCfgSelectItem (QemuFwCfgItemInterfaceVersion);
+ Revision = QemuFwCfgRead32 ();
+ DEBUG ((EFI_D_INFO, "FW CFG Revision: 0x%x\n", Revision));
+ if ((Signature != SIGNATURE_32 ('Q', 'E', 'M', 'U')) ||
+ (Revision < 1)
+ ) {
+ DEBUG ((EFI_D_INFO, "QemuFwCfg interface not supported.\n"));
+ mQemuFwCfgSupported = FALSE;
+ return RETURN_SUCCESS;
+ }
+
+ DEBUG ((EFI_D_INFO, "QemuFwCfg interface is supported.\n"));
+ return RETURN_SUCCESS;
+}
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