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Diffstat (limited to 'OvmfPkg/Include/Library/PciCapLib.h')
-rw-r--r-- | OvmfPkg/Include/Library/PciCapLib.h | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/OvmfPkg/Include/Library/PciCapLib.h b/OvmfPkg/Include/Library/PciCapLib.h new file mode 100644 index 0000000000..22a1ad624b --- /dev/null +++ b/OvmfPkg/Include/Library/PciCapLib.h @@ -0,0 +1,429 @@ +/** @file
+ Library class to work with PCI capabilities in PCI config space.
+
+ Provides functions to parse capabilities lists, and to locate, describe, read
+ and write capabilities. PCI config space access is abstracted away.
+
+ Copyright (C) 2018, Red Hat, Inc.
+
+ 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.
+**/
+
+#ifndef __PCI_CAP_LIB_H__
+#define __PCI_CAP_LIB_H__
+
+#include <Uefi/UefiBaseType.h>
+
+//
+// Base structure for representing a PCI device -- down to the PCI function
+// level -- for the purposes of this library class. This is a forward
+// declaration that is completed below. Concrete implementations are supposed
+// to inherit and extend this type.
+//
+typedef struct PCI_CAP_DEV PCI_CAP_DEV;
+
+/**
+ Read the config space of a given PCI device (both normal and extended).
+
+ PCI_CAP_DEV_READ_CONFIG performs as few config space accesses as possible
+ (without attempting 64-bit wide accesses).
+
+ PCI_CAP_DEV_READ_CONFIG returns an unspecified error if accessing Size bytes
+ from SourceOffset exceeds the config space limit of the PCI device. Fewer
+ than Size bytes may have been read in this case.
+
+ @param[in] PciDevice Implementation-specific unique representation
+ of the PCI device in the PCI hierarchy.
+
+ @param[in] SourceOffset Source offset in the config space of the PCI
+ device to start reading from.
+
+ @param[out] DestinationBuffer Buffer to store the read data to.
+
+ @param[in] Size The number of bytes to transfer.
+
+ @retval RETURN_SUCCESS Size bytes have been transferred from config space to
+ DestinationBuffer.
+
+ @return Unspecified error codes. Fewer than Size bytes may
+ have been read.
+**/
+typedef
+RETURN_STATUS
+(EFIAPI *PCI_CAP_DEV_READ_CONFIG) (
+ IN PCI_CAP_DEV *PciDevice,
+ IN UINT16 SourceOffset,
+ OUT VOID *DestinationBuffer,
+ IN UINT16 Size
+ );
+
+/**
+ Write the config space of a given PCI device (both normal and extended).
+
+ PCI_CAP_DEV_WRITE_CONFIG performs as few config space accesses as possible
+ (without attempting 64-bit wide accesses).
+
+ PCI_CAP_DEV_WRITE_CONFIG returns an unspecified error if accessing Size bytes
+ at DestinationOffset exceeds the config space limit of the PCI device. Fewer
+ than Size bytes may have been written in this case.
+
+ @param[in] PciDevice Implementation-specific unique representation
+ of the PCI device in the PCI hierarchy.
+
+ @param[in] DestinationOffset Destination offset in the config space of the
+ PCI device to start writing at.
+
+ @param[in] SourceBuffer Buffer to read the data to be stored from.
+
+ @param[in] Size The number of bytes to transfer.
+
+ @retval RETURN_SUCCESS Size bytes have been transferred from SourceBuffer to
+ config space.
+
+ @return Unspecified error codes. Fewer than Size bytes may
+ have been written.
+**/
+typedef
+RETURN_STATUS
+(EFIAPI *PCI_CAP_DEV_WRITE_CONFIG) (
+ IN PCI_CAP_DEV *PciDevice,
+ IN UINT16 DestinationOffset,
+ IN VOID *SourceBuffer,
+ IN UINT16 Size
+ );
+
+//
+// Complete the PCI_CAP_DEV type here. The base abstraction only requires
+// config space accessors.
+//
+struct PCI_CAP_DEV {
+ PCI_CAP_DEV_READ_CONFIG ReadConfig;
+ PCI_CAP_DEV_WRITE_CONFIG WriteConfig;
+};
+
+//
+// Opaque data structure representing parsed PCI Capabilities Lists.
+//
+typedef struct PCI_CAP_LIST PCI_CAP_LIST;
+
+//
+// Opaque data structure representing a PCI Capability in a parsed Capability
+// List.
+//
+typedef struct PCI_CAP PCI_CAP;
+
+//
+// Distinguishes whether a Capability ID is 8-bit wide and interpreted in
+// normal config space, or 16-bit wide and interpreted in extended config
+// space. Capability ID definitions are relative to domain.
+//
+typedef enum {
+ PciCapNormal,
+ PciCapExtended
+} PCI_CAP_DOMAIN;
+
+//
+// Public data structure that PciCapGetInfo() fills in about a PCI_CAP object.
+//
+typedef struct {
+ PCI_CAP_DOMAIN Domain;
+ UINT16 CapId;
+ //
+ // The capability identified by Domain and CapId may have multiple instances
+ // in config space. NumInstances provides the total count of occurrences of
+ // the capability. It is always positive.
+ //
+ UINT16 NumInstances;
+ //
+ // Instance is the serial number, in capabilities list traversal order (not
+ // necessarily config space offset order), of the one capability instance
+ // that PciCapGetInfo() is reporting about. Instance is always smaller than
+ // NumInstances.
+ //
+ UINT16 Instance;
+ //
+ // The offset in config space at which the capability header of the
+ // capability instance starts.
+ //
+ UINT16 Offset;
+ //
+ // The deduced maximum size of the capability instance, including the
+ // capability header. This hint is an upper bound, calculated -- without
+ // regard to the internal structure of the capability -- from (a) the next
+ // lowest offset in configuration space that is known to be used by another
+ // capability, and (b) from the end of the config space identified by Domain,
+ // whichever is lower.
+ //
+ UINT16 MaxSizeHint;
+ //
+ // The version number of the capability instance. Always zero when Domain is
+ // PciCapNormal.
+ //
+ UINT8 Version;
+} PCI_CAP_INFO;
+
+
+/**
+ Parse the capabilities lists (both normal and extended, as applicable) of a
+ PCI device.
+
+ If the PCI device has no capabilities, that per se will not fail
+ PciCapListInit(); an empty capabilities list will be represented.
+
+ If the PCI device is found to be PCI Express, then an attempt will be made to
+ parse the extended capabilities list as well. If the first extended config
+ space access -- via PciDevice->ReadConfig() with SourceOffset=0x100 and
+ Size=4 -- fails, that per se will not fail PciCapListInit(); the device will
+ be assumed to have no extended capabilities.
+
+ @param[in] PciDevice Implementation-specific unique representation of the
+ PCI device in the PCI hierarchy.
+
+ @param[out] CapList Opaque data structure that holds an in-memory
+ representation of the parsed capabilities lists of
+ PciDevice.
+
+ @retval RETURN_SUCCESS The capabilities lists have been parsed from
+ config space.
+
+ @retval RETURN_OUT_OF_RESOURCES Memory allocation failed.
+
+ @retval RETURN_DEVICE_ERROR A loop or some other kind of invalid pointer
+ was detected in the capabilities lists of
+ PciDevice.
+
+ @return Error codes propagated from
+ PciDevice->ReadConfig().
+**/
+RETURN_STATUS
+EFIAPI
+PciCapListInit (
+ IN PCI_CAP_DEV *PciDevice,
+ OUT PCI_CAP_LIST **CapList
+ );
+
+
+/**
+ Free the resources used by CapList.
+
+ @param[in] CapList The PCI_CAP_LIST object to free, originally produced by
+ PciCapListInit().
+**/
+VOID
+EFIAPI
+PciCapListUninit (
+ IN PCI_CAP_LIST *CapList
+ );
+
+
+/**
+ Locate a capability instance in the parsed capabilities lists.
+
+ @param[in] CapList The PCI_CAP_LIST object produced by PciCapListInit().
+
+ @param[in] Domain Distinguishes whether CapId is 8-bit wide and
+ interpreted in normal config space, or 16-bit wide and
+ interpreted in extended config space. Capability ID
+ definitions are relative to domain.
+
+ @param[in] CapId Capability identifier to look up.
+
+ @param[in] Instance Domain and CapId may identify a multi-instance
+ capability. When Instance is zero, the first instance of
+ the capability is located (in list traversal order --
+ which may not mean increasing config space offset
+ order). Higher Instance values locate subsequent
+ instances of the same capability (in list traversal
+ order).
+
+ @param[out] Cap The capability instance that matches the search
+ criteria. Cap is owned by CapList and becomes invalid
+ when CapList is freed with PciCapListUninit().
+ PciCapListFindCap() may be called with Cap set to NULL,
+ in order to test the existence of a specific capability
+ instance.
+
+ @retval RETURN_SUCCESS The capability instance identified by (Domain,
+ CapId, Instance) has been found.
+
+ @retval RETURN_NOT_FOUND The requested (Domain, CapId, Instance) capability
+ instance does not exist.
+**/
+RETURN_STATUS
+EFIAPI
+PciCapListFindCap (
+ IN PCI_CAP_LIST *CapList,
+ IN PCI_CAP_DOMAIN Domain,
+ IN UINT16 CapId,
+ IN UINT16 Instance,
+ OUT PCI_CAP **Cap OPTIONAL
+ );
+
+
+/**
+ Locate the first instance of the capability given by (Domain, CapId) such
+ that the instance's Version is greater than or equal to MinVersion.
+
+ This is a convenience function that may save client code calls to
+ PciCapListFindCap() and PciCapGetInfo().
+
+ @param[in] CapList The PCI_CAP_LIST object produced by PciCapListInit().
+
+ @param[in] Domain Distinguishes whether CapId is 8-bit wide and
+ interpreted in normal config space, or 16-bit wide and
+ interpreted in extended config space. Capability ID
+ definitions are relative to domain.
+
+ @param[in] CapId Capability identifier to look up.
+
+ @param[in] MinVersion The minimum version that the capability instance is
+ required to have. Note that all capability instances
+ in Domain=PciCapNormal have Version=0.
+
+ @param[out] Cap The first capability instance that matches the search
+ criteria. Cap is owned by CapList and becomes invalid
+ when CapList is freed with PciCapListUninit().
+ PciCapListFindCapVersion() may be called with Cap set
+ to NULL, in order just to test whether the search
+ criteria are satisfiable.
+
+ @retval RETURN_SUCCESS The first capability instance matching (Domain,
+ CapId, MinVersion) has been located.
+
+ @retval RETURN_NOT_FOUND No capability instance matches (Domain, CapId,
+ MinVersion).
+**/
+RETURN_STATUS
+EFIAPI
+PciCapListFindCapVersion (
+ IN PCI_CAP_LIST *CapList,
+ IN PCI_CAP_DOMAIN Domain,
+ IN UINT16 CapId,
+ IN UINT8 MinVersion,
+ OUT PCI_CAP **Cap OPTIONAL
+ );
+
+
+/**
+ Get information about a PCI Capability instance.
+
+ @param[in] Cap The capability instance to get info about, located with
+ PciCapListFindCap*().
+
+ @param[out] Info A PCI_CAP_INFO structure that describes the properties of
+ Cap.
+
+ @retval RETURN_SUCCESS Fields of Info have been set.
+
+ @return Unspecified error codes, if filling in Info failed
+ for some reason.
+**/
+RETURN_STATUS
+EFIAPI
+PciCapGetInfo (
+ IN PCI_CAP *Cap,
+ OUT PCI_CAP_INFO *Info
+ );
+
+
+/**
+ Read a slice of a capability instance.
+
+ The function performs as few config space accesses as possible (without
+ attempting 64-bit wide accesses). PciCapRead() performs bounds checking on
+ SourceOffsetInCap and Size, and only invokes PciDevice->ReadConfig() if the
+ requested transfer falls within Cap.
+
+ @param[in] PciDevice Implementation-specific unique representation
+ of the PCI device in the PCI hierarchy.
+
+ @param[in] Cap The capability instance to read, located with
+ PciCapListFindCap*().
+
+ @param[in] SourceOffsetInCap Source offset relative to the capability
+ header to start reading from. A zero value
+ refers to the first byte of the capability
+ header.
+
+ @param[out] DestinationBuffer Buffer to store the read data to.
+
+ @param[in] Size The number of bytes to transfer.
+
+ @retval RETURN_SUCCESS Size bytes have been transferred from Cap to
+ DestinationBuffer.
+
+ @retval RETURN_BAD_BUFFER_SIZE Reading Size bytes starting from
+ SourceOffsetInCap would not (entirely) be
+ contained within Cap, as suggested by
+ PCI_CAP_INFO.MaxSizeHint. No bytes have been
+ read.
+
+ @return Error codes propagated from
+ PciDevice->ReadConfig(). Fewer than Size
+ bytes may have been read.
+**/
+RETURN_STATUS
+EFIAPI
+PciCapRead (
+ IN PCI_CAP_DEV *PciDevice,
+ IN PCI_CAP *Cap,
+ IN UINT16 SourceOffsetInCap,
+ OUT VOID *DestinationBuffer,
+ IN UINT16 Size
+ );
+
+
+/**
+ Write a slice of a capability instance.
+
+ The function performs as few config space accesses as possible (without
+ attempting 64-bit wide accesses). PciCapWrite() performs bounds checking on
+ DestinationOffsetInCap and Size, and only invokes PciDevice->WriteConfig() if
+ the requested transfer falls within Cap.
+
+ @param[in] PciDevice Implementation-specific unique
+ representation of the PCI device in the
+ PCI hierarchy.
+
+ @param[in] Cap The capability instance to write, located
+ with PciCapListFindCap*().
+
+ @param[in] DestinationOffsetInCap Destination offset relative to the
+ capability header to start writing at. A
+ zero value refers to the first byte of the
+ capability header.
+
+ @param[in] SourceBuffer Buffer to read the data to be stored from.
+
+ @param[in] Size The number of bytes to transfer.
+
+ @retval RETURN_SUCCESS Size bytes have been transferred from
+ SourceBuffer to Cap.
+
+ @retval RETURN_BAD_BUFFER_SIZE Writing Size bytes starting at
+ DestinationOffsetInCap would not (entirely)
+ be contained within Cap, as suggested by
+ PCI_CAP_INFO.MaxSizeHint. No bytes have been
+ written.
+
+ @return Error codes propagated from
+ PciDevice->WriteConfig(). Fewer than Size
+ bytes may have been written.
+**/
+RETURN_STATUS
+EFIAPI
+PciCapWrite (
+ IN PCI_CAP_DEV *PciDevice,
+ IN PCI_CAP *Cap,
+ IN UINT16 DestinationOffsetInCap,
+ IN VOID *SourceBuffer,
+ IN UINT16 Size
+ );
+
+#endif // __PCI_CAP_LIB_H__
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