2 This code abstracts the CPU IO Protocol which installed by some platform or chipset-specific
3 PEIM that abstracts the processor-visible I/O operations.
5 Copyright (c) 2007 - 2009, Intel Corporation
6 All rights reserved. This program and the accompanying materials
7 are licensed and made available under the terms and conditions of the BSD License
8 which accompanies this distribution. The full text of the license may be found at
9 http://opensource.org/licenses/bsd-license.php
11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
14 @par Revision Reference:
15 CPU IO Protocol is defined in Framework of EFI CPU IO Protocol Spec
25 #define EFI_CPU_IO_PROTOCOL_GUID \
27 0xB0732526, 0x38C8, 0x4b40, {0x88, 0x77, 0x61, 0xC7, 0xB0, 0x6A, 0xAC, 0x45 } \
30 typedef struct _EFI_CPU_IO_PROTOCOL EFI_CPU_IO_PROTOCOL
;
33 /// Enumeration that defines the width of the I/O operation.
40 EfiCpuIoWidthFifoUint8
,
41 EfiCpuIoWidthFifoUint16
,
42 EfiCpuIoWidthFifoUint32
,
43 EfiCpuIoWidthFifoUint64
,
44 EfiCpuIoWidthFillUint8
,
45 EfiCpuIoWidthFillUint16
,
46 EfiCpuIoWidthFillUint32
,
47 EfiCpuIoWidthFillUint64
,
49 } EFI_CPU_IO_PROTOCOL_WIDTH
;
52 Enables a driver to access memory-mapped registers in the EFI system memory space.
53 Or, Enables a driver to access registers in the EFI CPU I/O space.
55 @param[in] This A pointer to the EFI_CPU_IO_PROTOCOL instance.
56 @param[in] Width Signifies the width of the I/O or Memory operation.
57 @param[in] Address The base address of the I/O or Memoryoperation.
58 @param[in] Count The number of I/O or Memory operations to perform.
59 The number of bytes moved is Width size * Count, starting at Address.
60 @param[in, out] Buffer For read operations, the destination buffer to store the results.
61 For write operations, the source buffer from which to write data.
63 @retval EFI_SUCCESS The data was read from or written to the EFI system.
64 @retval EFI_INVALID_PARAMETER Width is invalid for this EFI system.Or Buffer is NULL.
65 @retval EFI_UNSUPPORTED The Buffer is not aligned for the given Width.
66 Or,The address range specified by Address, Width, and Count is not valid for this EFI system.
71 (EFIAPI
*EFI_CPU_IO_PROTOCOL_IO_MEM
)(
72 IN EFI_CPU_IO_PROTOCOL
*This
,
73 IN EFI_CPU_IO_PROTOCOL_WIDTH Width
,
80 /// Servies for read and write accesses.
84 /// This service provides the various modalities of memory and I/O read.
86 EFI_CPU_IO_PROTOCOL_IO_MEM Read
;
88 /// This service provides the various modalities of memory and I/O write.
90 EFI_CPU_IO_PROTOCOL_IO_MEM Write
;
91 } EFI_CPU_IO_PROTOCOL_ACCESS
;
94 /// Provides the basic memory and I/O interfaces that are used to abstract
95 /// accesses to devices in a system.
97 struct _EFI_CPU_IO_PROTOCOL
{
99 /// Enables a driver to access memory-mapped registers in the EFI system memory space.
101 EFI_CPU_IO_PROTOCOL_ACCESS Mem
;
103 /// Enables a driver to access registers in the EFI CPU I/O space.
105 EFI_CPU_IO_PROTOCOL_ACCESS Io
;
108 extern EFI_GUID gEfiCpuIoProtocolGuid
;