audk/ArmPkg/Include/Library/ArmMtlLib.h

131 lines
3.4 KiB
C

/** @file
Copyright (c) 2017-2018, Arm Limited. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent
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_ */