#include "DebugPort.h"

Functions
EFI_DEVICE_PATH_PROTOCOL *	GetDebugPortVariable (VOID)

EFI_STATUS EFIAPI	InitializeDebugPortDriver (IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable)

EFI_STATUS EFIAPI	DebugPortSupported (IN EFI_DRIVER_BINDING_PROTOCOL This, IN EFI_HANDLE ControllerHandle, IN EFI_DEVICE_PATH_PROTOCOL RemainingDevicePath)

EFI_STATUS EFIAPI	DebugPortStart (IN EFI_DRIVER_BINDING_PROTOCOL This, IN EFI_HANDLE ControllerHandle, IN EFI_DEVICE_PATH_PROTOCOL RemainingDevicePath)

EFI_STATUS EFIAPI	DebugPortStop (IN EFI_DRIVER_BINDING_PROTOCOL This, IN EFI_HANDLE ControllerHandle, IN UINTN NumberOfChildren, IN EFI_HANDLE ChildHandleBuffer)

EFI_STATUS EFIAPI	DebugPortReset (IN EFI_DEBUGPORT_PROTOCOL *This)

EFI_STATUS EFIAPI	DebugPortRead (IN EFI_DEBUGPORT_PROTOCOL This, IN UINT32 Timeout, IN OUT UINTN BufferSize, IN VOID *Buffer)

EFI_STATUS EFIAPI	DebugPortWrite (IN EFI_DEBUGPORT_PROTOCOL This, IN UINT32 Timeout, IN OUT UINTN BufferSize, OUT VOID *Buffer)

EFI_STATUS EFIAPI	DebugPortPoll (IN EFI_DEBUGPORT_PROTOCOL *This)

EFI_STATUS EFIAPI	ImageUnloadHandler (EFI_HANDLE ImageHandle)

Variables
EFI_DRIVER_BINDING_PROTOCOL	gDebugPortDriverBinding

DEBUGPORT_DEVICE	mDebugPortDevice

Detailed Description

Top level C file for debugport driver. Contains initialization function. This driver layers on top of SerialIo. ALL CODE IN THE SERIALIO STACK MUST BE RE-ENTRANT AND CALLABLE FROM INTERRUPT CONTEXT

Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file DebugPort.c.

Function Documentation

◆ DebugPortPoll()

EFI_STATUS EFIAPI DebugPortPoll ( IN EFI_DEBUGPORT_PROTOCOL * This )

DebugPort protocol member function. Calls SerialIo:Write() after setting if it's different than the last SerialIo access.

Parameters

This	Pointer to DebugPort protocol.

Return values

EFI_SUCCESS	At least 1 character is ready to be read from the DebugPort interface.
EFI_NOT_READY	There are no characters ready to read from the DebugPort interface
EFI_DEVICE_ERROR	A hardware failure occurred... (from SerialIo)

Definition at line 644 of file DebugPort.c.

◆ DebugPortRead()

EFI_STATUS EFIAPI DebugPortRead	(	IN EFI_DEBUGPORT_PROTOCOL *	This,
		IN UINT32	Timeout,
		IN OUT UINTN *	BufferSize,
		IN VOID *	Buffer
	)

DebugPort protocol member function. Calls SerialIo:Read() after setting if it's different than the last SerialIo access.

Parameters

This	Pointer to DebugPort protocol.
Timeout	Timeout value.
BufferSize	On input, the size of Buffer. On output, the amount of data actually written.
Buffer	Pointer to buffer to read.

Return values

EFI_SUCCESS
others

Definition at line 534 of file DebugPort.c.

◆ DebugPortReset()

EFI_STATUS EFIAPI DebugPortReset ( IN EFI_DEBUGPORT_PROTOCOL * This )

DebugPort protocol member function. Calls SerialIo:GetControl to flush buffer. We cannot call SerialIo:SetAttributes because it uses pool services, which use locks, which affect TPL, so it's not interrupt context safe or re-entrant. SerialIo:Reset() calls SetAttributes, so it can't be used either.

The port itself should be fine since it was set up during initialization.

Parameters

This	Protocol instance pointer.

Returns: EFI_SUCCESS Always.

Definition at line 503 of file DebugPort.c.

◆ DebugPortStart()

EFI_STATUS EFIAPI DebugPortStart	(	IN EFI_DRIVER_BINDING_PROTOCOL *	This,
		IN EFI_HANDLE	ControllerHandle,
		IN EFI_DEVICE_PATH_PROTOCOL *	RemainingDevicePath
	)

Binds exclusively to serial io on the controller handle, Produces DebugPort protocol and DevicePath on new handle.

Parameters

This	Protocol instance pointer.
ControllerHandle	Handle of device to bind driver to.
RemainingDevicePath	Optional parameter use to pick a specific child device to start.

Return values

EFI_SUCCESS	This driver is added to ControllerHandle.
EFI_OUT_OF_RESOURCES	Fails to allocate memory for device.
others	Some error occurs.

Definition at line 265 of file DebugPort.c.

◆ DebugPortStop()

EFI_STATUS EFIAPI DebugPortStop	(	IN EFI_DRIVER_BINDING_PROTOCOL *	This,
		IN EFI_HANDLE	ControllerHandle,
		IN UINTN	NumberOfChildren,
		IN EFI_HANDLE *	ChildHandleBuffer
	)

Stop this driver on ControllerHandle by removing Serial IO protocol on the ControllerHandle.

Parameters

This	Protocol instance pointer.
ControllerHandle	Handle of device to stop driver on
NumberOfChildren	Number of Handles in ChildHandleBuffer. If number of children is zero stop the entire bus driver.
ChildHandleBuffer	List of Child Handles to Stop.

Return values

EFI_SUCCESS	This driver is removed ControllerHandle.
other	This driver was not removed from this device.

Definition at line 412 of file DebugPort.c.

◆ DebugPortSupported()

EFI_STATUS EFIAPI DebugPortSupported	(	IN EFI_DRIVER_BINDING_PROTOCOL *	This,
		IN EFI_HANDLE	ControllerHandle,
		IN EFI_DEVICE_PATH_PROTOCOL *	RemainingDevicePath
	)

Checks to see if there's not already a DebugPort interface somewhere.

If there's a DEBUGPORT variable, the device path must match exactly. If there's no DEBUGPORT variable, then device path is not checked and does not matter. Checks to see that there's a serial io interface on the controller handle that can be bound BY_DRIVER | EXCLUSIVE. If all these tests succeed, then we return EFI_SUCCESS, else, EFI_UNSUPPORTED or other error returned by OpenProtocol.

Parameters

This	Protocol instance pointer.
ControllerHandle	Handle of device to test.
RemainingDevicePath	Optional parameter use to pick a specific child device to start.

Return values

EFI_SUCCESS	This driver supports this device.
EFI_UNSUPPORTED	Debug Port device is not supported.
EFI_OUT_OF_RESOURCES	Fails to allocate memory for device.
others	Some error occurs.

Definition at line 165 of file DebugPort.c.

◆ DebugPortWrite()

EFI_STATUS EFIAPI DebugPortWrite	(	IN EFI_DEBUGPORT_PROTOCOL *	This,
		IN UINT32	Timeout,
		IN OUT UINTN *	BufferSize,
		OUT VOID *	Buffer
	)

DebugPort protocol member function. Calls SerialIo:Write() Writes 8 bytes at a time and does a GetControl between 8 byte writes to help insure reads are interspersed This is poor-man's flow control.

Parameters

This	Pointer to DebugPort protocol.
Timeout	Timeout value.
BufferSize	On input, the size of Buffer. On output, the amount of data actually written.
Buffer	Pointer to buffer to read.

Return values

EFI_SUCCESS	The data was written.
others	Fails when writting datas to debug port device.

Definition at line 592 of file DebugPort.c.

◆ GetDebugPortVariable()

EFI_DEVICE_PATH_PROTOCOL * GetDebugPortVariable ( VOID )

Local worker function to obtain device path information from DebugPort variable.

Records requested settings in DebugPort device structure.

Definition at line 54 of file DebugPort.c.

◆ ImageUnloadHandler()

EFI_STATUS EFIAPI ImageUnloadHandler ( EFI_HANDLE ImageHandle )

Unload function that is registered in the LoadImage protocol. It un-installs protocols produced and deallocates pool used by the driver. Called by the core when unloading the driver.

Parameters

ImageHandle

Return values

EFI_SUCCESS	Unload Debug Port driver successfully.
EFI_ABORTED	Serial IO is still binding.

Definition at line 683 of file DebugPort.c.

◆ InitializeDebugPortDriver()

EFI_STATUS EFIAPI InitializeDebugPortDriver	(	IN EFI_HANDLE	ImageHandle,
		IN EFI_SYSTEM_TABLE *	SystemTable
	)

Debug Port Driver entry point.

Reads DebugPort variable to determine what device and settings to use as the debug port. Binds exclusively to SerialIo. Reverts to defaults if no variable is found.

Parameters

[in]	ImageHandle	The firmware allocated handle for the EFI image.
[in]	SystemTable	A pointer to the EFI System Table.

Return values

EFI_SUCCESS	The entry point is executed successfully.
EFI_OUT_OF_RESOURCES	Fails to allocate memory for device.
other	Some error occurs when executing this entry point.

Definition at line 119 of file DebugPort.c.

Variable Documentation

◆ gDebugPortDriverBinding

EFI_DRIVER_BINDING_PROTOCOL gDebugPortDriverBinding

Initial value:

= {
  DebugPortSupported,
  DebugPortStart,
  DebugPortStop,
  DEBUGPORT_DRIVER_VERSION,
  NULL,
  NULL
}

Definition at line 17 of file DebugPort.c.

◆ mDebugPortDevice

DEBUGPORT_DEVICE mDebugPortDevice

Initial value:

= {
  DEBUGPORT_DEVICE_SIGNATURE,
  (EFI_HANDLE)0,
  (EFI_HANDLE)0,
  (EFI_DEVICE_PATH_PROTOCOL *)NULL,
  {
    DebugPortReset,
    DebugPortWrite,
    DebugPortRead,
    DebugPortPoll
  },
  (EFI_HANDLE)0,
  (EFI_SERIAL_IO_PROTOCOL *)NULL,
  DEBUGPORT_UART_DEFAULT_BAUDRATE,
  DEBUGPORT_UART_DEFAULT_FIFO_DEPTH,
  DEBUGPORT_UART_DEFAULT_TIMEOUT,
  (EFI_PARITY_TYPE)DEBUGPORT_UART_DEFAULT_PARITY,
  DEBUGPORT_UART_DEFAULT_DATA_BITS,
  (EFI_STOP_BITS_TYPE)DEBUGPORT_UART_DEFAULT_STOP_BITS
}

Definition at line 26 of file DebugPort.c.

Functions

Variables

Detailed Description

Function Documentation

◆ DebugPortPoll()

◆ DebugPortRead()

◆ DebugPortReset()

◆ DebugPortStart()

◆ DebugPortStop()

◆ DebugPortSupported()

◆ DebugPortWrite()

◆ GetDebugPortVariable()

◆ ImageUnloadHandler()

◆ InitializeDebugPortDriver()

Variable Documentation

◆ gDebugPortDriverBinding

◆ mDebugPortDevice