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-rw-r--r--SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/SerialIo.c722
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diff --git a/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/SerialIo.c b/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/SerialIo.c
new file mode 100644
index 0000000000..726eec69c4
--- /dev/null
+++ b/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/SerialIo.c
@@ -0,0 +1,722 @@
+/** @file
+ Install Serial IO Protocol that layers on top of a Debug Communication Library instance.
+
+ Copyright (c) 2012, Intel Corporation. All rights reserved.<BR>
+ 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.
+
+**/
+
+#include "DxeDebugAgentLib.h"
+
+//
+// Serial I/O Protocol Interface defintions.
+//
+
+/**
+ Reset serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+
+ @retval EFI_SUCCESS Reset successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialReset (
+ IN EFI_SERIAL_IO_PROTOCOL *This
+ );
+
+/**
+ Set new attributes to a serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in] BaudRate The baudrate of the serial device.
+ @param[in] ReceiveFifoDepth The depth of receive FIFO buffer.
+ @param[in] Timeout The request timeout for a single char.
+ @param[in] Parity The type of parity used in serial device.
+ @param[in] DataBits Number of databits used in serial device.
+ @param[in] StopBits Number of stopbits used in serial device.
+
+ @retval EFI_SUCCESS The new attributes were set.
+ @retval EFI_INVALID_PARAMETER One or more attributes have an unsupported value.
+ @retval EFI_DEVICE_ERROR The serial device is not functioning correctly (no return).
+
+**/
+EFI_STATUS
+EFIAPI
+SerialSetAttributes (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN UINT64 BaudRate,
+ IN UINT32 ReceiveFifoDepth,
+ IN UINT32 Timeout,
+ IN EFI_PARITY_TYPE Parity,
+ IN UINT8 DataBits,
+ IN EFI_STOP_BITS_TYPE StopBits
+ );
+
+/**
+ Set Control Bits.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in] Control Control bits that can be settable.
+
+ @retval EFI_SUCCESS New Control bits were set successfully.
+ @retval EFI_UNSUPPORTED The Control bits wanted to set are not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialSetControl (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN UINT32 Control
+ );
+
+/**
+ Get ControlBits.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[out] Control Control signals of the serial device.
+
+ @retval EFI_SUCCESS Get Control signals successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialGetControl (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ OUT UINT32 *Control
+ );
+
+/**
+ Write the specified number of bytes to serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in, out] BufferSize On input the size of Buffer, on output the amount of
+ data actually written.
+ @param[in] Buffer The buffer of data to write.
+
+ @retval EFI_SUCCESS The data were written successfully.
+ @retval EFI_DEVICE_ERROR The device reported an error.
+ @retval EFI_TIMEOUT The write operation was stopped due to timeout.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialWrite (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN OUT UINTN *BufferSize,
+ IN VOID *Buffer
+ );
+
+/**
+ Read the specified number of bytes from serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in, out] BufferSize On input the size of Buffer, on output the amount of
+ data returned in buffer.
+ @param[out] Buffer The buffer to return the data into.
+
+ @retval EFI_SUCCESS The data were read successfully.
+ @retval EFI_DEVICE_ERROR The device reported an error.
+ @retval EFI_TIMEOUT The read operation was stopped due to timeout.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialRead (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN OUT UINTN *BufferSize,
+ OUT VOID *Buffer
+ );
+
+//
+// Serial Driver Defaults
+//
+#define SERIAL_PORT_DEFAULT_RECEIVE_FIFO_DEPTH 1
+#define SERIAL_PORT_DEFAULT_TIMEOUT 1000000
+#define SERIAL_PORT_DEFAULT_CONTROL_MASK 0
+#define SERIAL_PORT_LOOPBACK_BUFFER_FULL BIT8
+
+//
+// EFI_SERIAL_IO_MODE instance
+//
+EFI_SERIAL_IO_MODE mSerialIoMode = {
+ SERIAL_PORT_DEFAULT_CONTROL_MASK,
+ SERIAL_PORT_DEFAULT_TIMEOUT,
+ 0, // BaudRate
+ SERIAL_PORT_DEFAULT_RECEIVE_FIFO_DEPTH,
+ 0, // DataBits
+ 0, // Parity
+ 0 // StopBits
+};
+
+//
+// EFI_SERIAL_IO_PROTOCOL instance
+//
+EFI_SERIAL_IO_PROTOCOL mSerialIo = {
+ SERIAL_IO_INTERFACE_REVISION,
+ SerialReset,
+ SerialSetAttributes,
+ SerialSetControl,
+ SerialGetControl,
+ SerialWrite,
+ SerialRead,
+ &mSerialIoMode
+};
+
+//
+// Serial IO Device Path definition
+//
+typedef struct {
+ VENDOR_DEVICE_PATH VendorDevicePath;
+ UART_DEVICE_PATH UartDevicePath;
+ EFI_DEVICE_PATH_PROTOCOL EndDevicePath;
+} SERIAL_IO_DEVICE_PATH;
+
+//
+// Serial IO Device Patch instance
+//
+SERIAL_IO_DEVICE_PATH mSerialIoDevicePath = {
+ {
+ {
+ HARDWARE_DEVICE_PATH,
+ HW_VENDOR_DP,
+ (UINT8) (sizeof (VENDOR_DEVICE_PATH)),
+ (UINT8) ((sizeof (VENDOR_DEVICE_PATH)) >> 8)
+ },
+ EFI_DEBUG_AGENT_GUID,
+ },
+ {
+ {
+ MESSAGING_DEVICE_PATH,
+ MSG_UART_DP,
+ (UINT8) (sizeof (UART_DEVICE_PATH)),
+ (UINT8) ((sizeof (UART_DEVICE_PATH)) >> 8)
+ },
+ 0,
+ 0, // BaudRate
+ 0, // DataBits
+ 0, // Parity
+ 0, // StopBits
+ },
+ {
+ END_DEVICE_PATH_TYPE,
+ END_ENTIRE_DEVICE_PATH_SUBTYPE,
+ {
+ END_DEVICE_PATH_LENGTH,
+ 0
+ }
+ }
+};
+
+#define DEBGU_SERIAL_IO_FIFO_DEPTH 10
+//
+// Data buffer for Terminal input character and Debug Symbols.
+// The depth is DEBGU_SERIAL_IO_FIFO_DEPTH.
+// Fields:
+// First UINT8: The index of the first data in array Data[].
+// Last UINT8: The index, which you can put a new data into array Data[].
+// Surplus UINT8: Identify how many data you can put into array Data[].
+// Data[] UINT8: An array, which used to store data.
+//
+typedef struct {
+ UINT8 First;
+ UINT8 Last;
+ UINT8 Surplus;
+ UINT8 Data[DEBGU_SERIAL_IO_FIFO_DEPTH];
+} DEBUG_SERIAL_FIFO;
+
+//
+// Global Varibles
+//
+EFI_HANDLE mSerialIoHandle = NULL;
+UINTN mLoopbackBuffer = 0;
+DEBUG_SERIAL_FIFO mSerialFifoForTerminal = {0, 0, DEBGU_SERIAL_IO_FIFO_DEPTH, { 0 }};
+DEBUG_SERIAL_FIFO mSerialFifoForDebug = {0, 0, DEBGU_SERIAL_IO_FIFO_DEPTH, { 0 }};
+
+/**
+ Detect whether specific FIFO is empty or not.
+
+ @param[in] Fifo A pointer to the Data Structure DEBUG_SERIAL_FIFO.
+
+ @return whether specific FIFO is empty or not.
+
+**/
+BOOLEAN
+IsDebugTermianlFifoEmpty (
+ IN DEBUG_SERIAL_FIFO *Fifo
+ )
+{
+ if (Fifo->Surplus == DEBGU_SERIAL_IO_FIFO_DEPTH) {
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/**
+ Detect whether specific FIFO is full or not.
+
+ @param[in] Fifo A pointer to the Data Structure DEBUG_SERIAL_FIFO.
+
+ @return whether specific FIFO is full or not.
+
+**/
+BOOLEAN
+IsDebugTerminalFifoFull (
+ IN DEBUG_SERIAL_FIFO *Fifo
+ )
+
+{
+ if (Fifo->Surplus == 0) {
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/**
+ Add data to specific FIFO.
+
+ @param[in] Fifo A pointer to the Data Structure DEBUG_SERIAL_FIFO.
+ @param[in] Data The data added to FIFO.
+
+ @retval EFI_SUCCESS Add data to specific FIFO successfully.
+ @retval EFI_OUT_OF_RESOURCE Failed to add data because FIFO is already full.
+
+**/
+EFI_STATUS
+DebugTerminalFifoAdd (
+ IN DEBUG_SERIAL_FIFO *Fifo,
+ IN UINT8 Data
+ )
+
+{
+ //
+ // if FIFO full can not add data
+ //
+ if (IsDebugTerminalFifoFull (Fifo)) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+ //
+ // FIFO is not full can add data
+ //
+ Fifo->Data[Fifo->Last] = Data;
+ Fifo->Surplus--;
+ Fifo->Last++;
+ if (Fifo->Last == DEBGU_SERIAL_IO_FIFO_DEPTH) {
+ Fifo->Last = 0;
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Remove data from specific FIFO.
+
+ @param[in] Fifo A pointer to the Data Structure DEBUG_SERIAL_FIFO.
+ @param[out] Data The data removed from FIFO.
+
+ @retval EFI_SUCCESS Remove data from specific FIFO successfully.
+ @retval EFI_OUT_OF_RESOURCE Failed to remove data because FIFO is empty.
+
+**/
+EFI_STATUS
+DebugTerminalFifoRemove (
+ IN DEBUG_SERIAL_FIFO *Fifo,
+ OUT UINT8 *Data
+ )
+{
+ //
+ // if FIFO is empty, no data can remove
+ //
+ if (IsDebugTermianlFifoEmpty (Fifo)) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+ //
+ // FIFO is not empty, can remove data
+ //
+ *Data = Fifo->Data[Fifo->First];
+ Fifo->Surplus++;
+ Fifo->First++;
+ if (Fifo->First == DEBGU_SERIAL_IO_FIFO_DEPTH) {
+ Fifo->First = 0;
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Notification function on EFI PCD protocol to install EFI Serial IO protocol based
+ on Debug Communication Library.
+
+ @param[in] Event The event of notify protocol.
+ @param[in] Context Notify event context.
+
+**/
+VOID
+EFIAPI
+InstallSerialIoNotification (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ )
+{
+ EFI_STATUS Status;
+
+ //
+ // Get Debug Port parameters from PCDs
+ //
+ mSerialIoDevicePath.UartDevicePath.BaudRate = PcdGet64 (PcdUartDefaultBaudRate);
+ mSerialIoDevicePath.UartDevicePath.DataBits = PcdGet8 (PcdUartDefaultDataBits);
+ mSerialIoDevicePath.UartDevicePath.Parity = PcdGet8 (PcdUartDefaultParity);
+ mSerialIoDevicePath.UartDevicePath.StopBits = PcdGet8 (PcdUartDefaultStopBits);
+
+ mSerialIoMode.BaudRate = mSerialIoDevicePath.UartDevicePath.BaudRate;
+ mSerialIoMode.DataBits = mSerialIoDevicePath.UartDevicePath.DataBits;
+ mSerialIoMode.Parity = mSerialIoDevicePath.UartDevicePath.Parity;
+ mSerialIoMode.StopBits = mSerialIoDevicePath.UartDevicePath.StopBits;
+
+ Status = gBS->InstallMultipleProtocolInterfaces (
+ &mSerialIoHandle,
+ &gEfiDevicePathProtocolGuid, &mSerialIoDevicePath,
+ &gEfiSerialIoProtocolGuid, &mSerialIo,
+ NULL
+ );
+ if (EFI_ERROR (Status)) {
+ DEBUG ((EFI_D_ERROR, "Debug Agent: Failed to install EFI Serial IO Protocol on Debug Port!\n"));
+ }
+}
+
+/**
+ Reset serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+
+ @retval EFI_SUCCESS Reset successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialReset (
+ IN EFI_SERIAL_IO_PROTOCOL *This
+ )
+{
+ mSerialIoMode.ControlMask = SERIAL_PORT_DEFAULT_CONTROL_MASK;
+ mLoopbackBuffer = 0;
+ //
+ // Not reset serial devcie hardware indeed.
+ //
+ return EFI_SUCCESS;
+}
+
+/**
+ Set new attributes to a serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in] BaudRate The baudrate of the serial device.
+ @param[in] ReceiveFifoDepth The depth of receive FIFO buffer.
+ @param[in] Timeout The request timeout for a single char.
+ @param[in] Parity The type of parity used in serial device.
+ @param[in] DataBits Number of databits used in serial device.
+ @param[in] StopBits Number of stopbits used in serial device.
+
+ @retval EFI_SUCCESS The new attributes were set.
+ @retval EFI_INVALID_PARAMETER One or more attributes have an unsupported value.
+ @retval EFI_DEVICE_ERROR The serial device is not functioning correctly (no return).
+
+**/
+EFI_STATUS
+EFIAPI
+SerialSetAttributes (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN UINT64 BaudRate,
+ IN UINT32 ReceiveFifoDepth,
+ IN UINT32 Timeout,
+ IN EFI_PARITY_TYPE Parity,
+ IN UINT8 DataBits,
+ IN EFI_STOP_BITS_TYPE StopBits
+ )
+{
+ //
+ // The Debug Communication Library does not support changing communications parameters, so unless
+ // the request is to use the default value or the value the Debug Communication Library is already
+ // using, then return EFI_INVALID_PARAMETER.
+ //
+ if (BaudRate != 0 && BaudRate != PcdGet64 (PcdUartDefaultBaudRate)) {
+ return EFI_INVALID_PARAMETER;
+ }
+ if (Parity != DefaultParity && Parity != PcdGet8 (PcdUartDefaultParity)) {
+ return EFI_INVALID_PARAMETER;
+ }
+ if (DataBits != 0 && DataBits != PcdGet8 (PcdUartDefaultDataBits)) {
+ return EFI_INVALID_PARAMETER;
+ }
+ if (StopBits != DefaultStopBits && StopBits != PcdGet8 (PcdUartDefaultStopBits)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // Update the Timeout value in the mode structure based on the request.
+ // The Debug Communication Library can not support a timeout on writes, but the timeout on
+ // reads can be provided by this module.
+ //
+ if (Timeout == 0) {
+ mSerialIoMode.Timeout = SERIAL_PORT_DEFAULT_TIMEOUT;
+ } else {
+ mSerialIoMode.Timeout = Timeout;
+ }
+
+ //
+ // Update the ReceiveFifoDepth value in the mode structure based on the request.
+ // This module assumes that the Debug Communication Library uses a FIFO depth of
+ // SERIAL_PORT_DEFAULT_RECEIVE_FIFO_DEPTH. The Debug Communication Library may actually be
+ // using a larger FIFO, but there is no way to tell.
+ //
+ if (ReceiveFifoDepth == 0 || ReceiveFifoDepth >= SERIAL_PORT_DEFAULT_RECEIVE_FIFO_DEPTH) {
+ mSerialIoMode.ReceiveFifoDepth = SERIAL_PORT_DEFAULT_RECEIVE_FIFO_DEPTH;
+ } else {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Set Control Bits.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in] Control Control bits that can be settable.
+
+ @retval EFI_SUCCESS New Control bits were set successfully.
+ @retval EFI_UNSUPPORTED The Control bits wanted to set are not supported.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialSetControl (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN UINT32 Control
+ )
+{
+ //
+ // The only control bit supported by this module is software loopback.
+ // If any other bit is set, then return an error
+ //
+ if ((Control & (~EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE)) != 0) {
+ return EFI_UNSUPPORTED;
+ }
+ mSerialIoMode.ControlMask = Control;
+ return EFI_SUCCESS;
+}
+
+/**
+ Get ControlBits.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[out] Control Control signals of the serial device.
+
+ @retval EFI_SUCCESS Get Control signals successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialGetControl (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ OUT UINT32 *Control
+ )
+{
+ DEBUG_PORT_HANDLE Handle;
+
+ Handle = GetDebugPortHandle ();
+
+ //
+ // Always assume the output buffer is empty and the Debug Communication Library can process
+ // more write requests.
+ //
+ *Control = mSerialIoMode.ControlMask | EFI_SERIAL_OUTPUT_BUFFER_EMPTY;
+
+ //
+ // Check to see if the Terminal FIFO is empty and
+ // check to see if the input buffer in the Debug Communication Library is empty
+ //
+ if (!IsDebugTermianlFifoEmpty (&mSerialFifoForTerminal) || DebugPortPollBuffer (Handle)) {
+ *Control &= ~EFI_SERIAL_INPUT_BUFFER_EMPTY;
+ }
+ return EFI_SUCCESS;
+}
+
+/**
+ Write the specified number of bytes to serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in, out] BufferSize On input the size of Buffer, on output the amount of
+ data actually written.
+ @param[in] Buffer The buffer of data to write.
+
+ @retval EFI_SUCCESS The data were written successfully.
+ @retval EFI_DEVICE_ERROR The device reported an error.
+ @retval EFI_TIMEOUT The write operation was stopped due to timeout.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialWrite (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN OUT UINTN *BufferSize,
+ IN VOID *Buffer
+ )
+{
+ DEBUG_PORT_HANDLE Handle;
+
+ Handle = GetDebugPortHandle ();
+
+ if ((mSerialIoMode.ControlMask & EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE) != 0) {
+ if (*BufferSize == 0) {
+ return EFI_SUCCESS;
+ }
+ if ((mLoopbackBuffer & SERIAL_PORT_LOOPBACK_BUFFER_FULL) != 0) {
+ *BufferSize = 0;
+ return EFI_TIMEOUT;
+ }
+ mLoopbackBuffer = SERIAL_PORT_LOOPBACK_BUFFER_FULL | *(UINT8 *)Buffer;
+ *BufferSize = 1;
+ } else {
+ *BufferSize = DebugPortWriteBuffer (Handle, Buffer, *BufferSize);
+ }
+ return EFI_SUCCESS;
+}
+
+/**
+ Read the specified number of bytes from serial device.
+
+ @param[in] This Pointer to EFI_SERIAL_IO_PROTOCOL.
+ @param[in, out] BufferSize On input the size of Buffer, on output the amount of
+ data returned in buffer.
+ @param[out] Buffer The buffer to return the data into.
+
+ @retval EFI_SUCCESS The data were read successfully.
+ @retval EFI_DEVICE_ERROR The device reported an error.
+ @retval EFI_TIMEOUT The read operation was stopped due to timeout.
+
+**/
+EFI_STATUS
+EFIAPI
+SerialRead (
+ IN EFI_SERIAL_IO_PROTOCOL *This,
+ IN OUT UINTN *BufferSize,
+ OUT VOID *Buffer
+ )
+{
+ EFI_STATUS Status;
+ UINTN Index;
+ UINT8 *Uint8Buffer;
+ BOOLEAN OldInterruptState;
+ DEBUG_PORT_HANDLE Handle;
+ UINT8 Data;
+
+ Handle = GetDebugPortHandle ();
+
+ //
+ // Save and disable Debug Timer interrupt to avoid it to access Debug Port
+ //
+ OldInterruptState = SaveAndSetDebugTimerInterrupt (FALSE);
+
+ Uint8Buffer = (UINT8 *)Buffer;
+ if ((mSerialIoMode.ControlMask & EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE) != 0) {
+ if ((mLoopbackBuffer & SERIAL_PORT_LOOPBACK_BUFFER_FULL) == 0) {
+ return EFI_TIMEOUT;
+ }
+ *Uint8Buffer = (UINT8)(mLoopbackBuffer & 0xff);
+ mLoopbackBuffer = 0;
+ *BufferSize = 1;
+ } else {
+ for (Index = 0; Index < *BufferSize; Index++) {
+ //
+ // Read input character from terminal FIFO firstly
+ //
+ Status = DebugTerminalFifoRemove (&mSerialFifoForTerminal, &Data);
+ if (Status == EFI_SUCCESS) {
+ *Uint8Buffer = Data;
+ Uint8Buffer ++;
+ continue;
+ }
+ //
+ // Read the input character from Debug Port
+ //
+ if (!DebugPortPollBuffer (Handle)) {
+ break;
+ }
+ DebugPortReadBuffer (Handle, &Data, 1, 0);
+
+ if (Data== DEBUG_STARTING_SYMBOL_ATTACH ||
+ Data == DEBUG_STARTING_SYMBOL_BREAK) {
+ //
+ // Add the debug symbol into Debug FIFO
+ //
+ DebugTerminalFifoAdd (&mSerialFifoForDebug, Data);
+ } else {
+ *Uint8Buffer = Data;
+ Uint8Buffer ++;
+ }
+ }
+ *BufferSize = (UINTN)Uint8Buffer - (UINTN)Buffer;
+ }
+
+ //
+ // Restore Debug Timer interrupt
+ //
+ SaveAndSetDebugTimerInterrupt (OldInterruptState);
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Read the Attach/Break-in symbols from the debug port.
+
+ @param[in] Handle Pointer to Debug Port handle.
+ @param[out] BreakSymbol Returned break symbol.
+
+ @retval EFI_SUCCESS Read the symbol in BreakSymbol.
+ @retval EFI_NOT_FOUND No read the break symbol.
+
+**/
+EFI_STATUS
+DebugReadBreakSymbol (
+ IN DEBUG_PORT_HANDLE Handle,
+ OUT UINT8 *BreakSymbol
+ )
+{
+ EFI_STATUS Status;
+ UINT8 Data;
+
+ Status = DebugTerminalFifoRemove (&mSerialFifoForDebug, &Data);
+ if (Status != EFI_SUCCESS) {
+ if (!DebugPortPollBuffer (Handle)) {
+ //
+ // No data in Debug Port buffer.
+ //
+ return EFI_NOT_FOUND;
+ } else {
+ //
+ // Read one character from Debug Port.
+ //
+ DebugPortReadBuffer (Handle, &Data, 1, 0);
+ if ((Data != DEBUG_STARTING_SYMBOL_ATTACH) && (Data != DEBUG_STARTING_SYMBOL_BREAK)) {
+ //
+ // If the data is not Break symbol, add it into Terminal FIFO
+ //
+ DebugTerminalFifoAdd (&mSerialFifoForTerminal, Data);
+ return EFI_NOT_FOUND;
+ }
+ }
+ }
+
+ *BreakSymbol = Data;
+ return EFI_SUCCESS;
+}