audk/ArmPkg/Include/Library/ArmMtlLib.h

138 lines
3.7 KiB
C

/** @file
Copyright (c) 2017-2018, Arm Limited. All rights reserved.
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.
System Control and Management Interface V1.0
http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/
DEN0056A_System_Control_and_Management_Interface.pdf
**/
#ifndef ARM_MTL_LIB_H_
#define ARM_MTL_LIB_H_
#include <Uefi/UefiBaseType.h>
// Ideally we don't need packed struct. However we can't rely on compilers.
#pragma pack(1)
typedef struct {
UINT32 Reserved1;
UINT32 ChannelStatus;
UINT64 Reserved2;
UINT32 Flags;
UINT32 Length;
UINT32 MessageHeader;
// NOTE: Since EDK2 does not allow flexible array member [] we declare
// here array of 1 element length. However below is used as a variable
// length array.
UINT32 Payload[1]; // size less object gives offset to payload.
} MTL_MAILBOX;
#pragma pack()
// Channel Type, Low-priority, and High-priority
typedef enum {
MTL_CHANNEL_TYPE_LOW = 0,
MTL_CHANNEL_TYPE_HIGH = 1
} MTL_CHANNEL_TYPE;
typedef struct {
UINT64 PhysicalAddress;
UINT32 ModifyMask;
UINT32 PreserveMask;
} MTL_DOORBELL;
typedef struct {
MTL_CHANNEL_TYPE ChannelType;
MTL_MAILBOX * CONST MailBox;
MTL_DOORBELL DoorBell;
} MTL_CHANNEL;
/** Wait until channel is free.
@param[in] Channel Pointer to a channel.
@param[in] TimeOutInMicroSeconds Time out in micro seconds.
@retval EFI_SUCCESS Channel is free.
@retval EFI_TIMEOUT Time out error.
**/
EFI_STATUS
MtlWaitUntilChannelFree (
IN MTL_CHANNEL *Channel,
IN UINTN TimeOutInMicroSeconds
);
/** Return the address of the message payload.
@param[in] Channel Pointer to a channel.
@retval UINT32* Pointer to the payload.
**/
UINT32*
MtlGetChannelPayload (
IN MTL_CHANNEL *Channel
);
/** Return pointer to a channel for the requested channel type.
@param[in] ChannelType ChannelType, Low or High priority channel.
MTL_CHANNEL_TYPE_LOW or
MTL_CHANNEL_TYPE_HIGH
@param[out] Channel Holds pointer to the channel.
@retval EFI_SUCCESS Pointer to channel is returned.
@retval EFI_UNSUPPORTED Requested channel type not supported.
**/
EFI_STATUS
MtlGetChannel (
IN MTL_CHANNEL_TYPE ChannelType,
OUT MTL_CHANNEL **Channel
);
/** Mark the channel busy and ring the doorbell.
@param[in] Channel Pointer to a channel.
@param[in] MessageHeader Message header.
@param[out] PayloadLength Message length.
@retval EFI_SUCCESS Message sent successfully.
@retval EFI_DEVICE_ERROR Channel is busy.
**/
EFI_STATUS
MtlSendMessage (
IN MTL_CHANNEL *Channel,
IN UINT32 MessageHeader,
OUT UINT32 PayloadLength
);
/** Wait for a response on a channel.
If channel is free after sending message, it implies SCP responded
with a response on the channel.
@param[in] Channel Pointer to a channel.
@retval EFI_SUCCESS Message received successfully.
@retval EFI_TIMEOUT Time out error.
**/
EFI_STATUS
MtlReceiveMessage (
IN MTL_CHANNEL *Channel,
OUT UINT32 *MessageHeader,
OUT UINT32 *PayloadLength
);
#endif /* ARM_MTL_LIB_H_ */