Files
reactos/drivers/base/kdcom/kdcom.c
Hermès Bélusca-Maïto 6c532e771e [FREELDR][KDCOM][KDGDB] Allow specifying the serial port address in the DEBUGPORT option
This is the same feature as the one that already exists in the
NTOS:KD!kdmain.c module used by the in-kernel KDBG debugger
(GCC builds), first introduced in commit 4ce30245de (r54473),
and documented at:
https://reactos.org/wiki/Debugging#Changing_the_serial_port_address

This feature is useful if one uses a PCI, PCIe, PCMCIA, or ExpressCard
serial card on real hardware (these cards are used e.g. with laptops
without a built-in serial port), or with AMT serial over LAN.
After determining the serial port I/O address (say, 0xCC00), specify
the debug port as follows:

/DEBUGPORT=COM:0xCC00

instead of the usual syntax: /DEBUGPORT=COMn (n an integer).

The same syntax can be used for debugging FreeLoader as well: in the
FREELDR.INI file, add a "Debug" line in the "FREELOADER" section,
as follows:

```
[FREELOADER]
Debug=/DEBUG /DEBUGPORT=COM:0xCC00 /BAUDRATE=115200
```

----

NOTE for KDCOM/KDGDB:

Since `strtoul()` is used, but isn't exported by ntoskrnl, link against
the "strtol" static library that has been introduced in commit d317d4fbcc
(r71481).
2026-03-21 00:10:21 +01:00

310 lines
7.2 KiB
C

/*
* COPYRIGHT: GPL, see COPYING in the top level directory
* PROJECT: ReactOS kernel
* FILE: drivers/base/kdcom/kdcom.c
* PURPOSE: COM port functions for the kernel debugger.
* PROGRAMMER: Timo Kreuzer (timo.kreuzer@reactos.org)
*/
#include "kddll.h"
#include <arc/arc.h>
#include <stdlib.h>
#include <ndk/halfuncs.h>
#include <cportlib/cportlib.h>
#include <cportlib/uartinfo.h>
/* GLOBALS ********************************************************************/
CPPORT KdComPort;
#ifdef KDDEBUG
CPPORT KdDebugComPort;
#endif
/* DEBUGGING ******************************************************************/
#ifdef KDDEBUG
#include <stdio.h>
ULONG KdpDbgPrint(const char *Format, ...)
{
va_list ap;
int Length;
char* ptr;
CHAR Buffer[512];
va_start(ap, Format);
Length = _vsnprintf(Buffer, sizeof(Buffer), Format, ap);
va_end(ap);
/* Check if we went past the buffer */
if (Length == -1)
{
/* Terminate it if we went over-board */
Buffer[sizeof(Buffer) - 1] = '\n';
/* Put maximum */
Length = sizeof(Buffer);
}
ptr = Buffer;
while (Length--)
{
if (*ptr == '\n')
CpPutByte(&KdDebugComPort, '\r');
CpPutByte(&KdDebugComPort, *ptr++);
}
return 0;
}
#endif
/* FUNCTIONS ******************************************************************/
NTSTATUS
NTAPI
KdD0Transition(VOID)
{
return STATUS_SUCCESS;
}
NTSTATUS
NTAPI
KdD3Transition(VOID)
{
return STATUS_SUCCESS;
}
NTSTATUS
NTAPI
KdSave(IN BOOLEAN SleepTransition)
{
/* Nothing to do on COM ports */
return STATUS_SUCCESS;
}
NTSTATUS
NTAPI
KdRestore(IN BOOLEAN SleepTransition)
{
/* Nothing to do on COM ports */
return STATUS_SUCCESS;
}
NTSTATUS
NTAPI
KdpPortInitialize(
_In_ PUCHAR PortAddress,
_In_ ULONG BaudRate)
{
NTSTATUS Status;
Status = CpInitialize(&KdComPort, PortAddress, BaudRate);
if (!NT_SUCCESS(Status))
return STATUS_INVALID_PARAMETER;
KdComPortInUse = KdComPort.Address;
return STATUS_SUCCESS;
}
/******************************************************************************
* \name KdDebuggerInitialize0
* \brief Phase 0 initialization.
* \param [opt] LoaderBlock Pointer to the Loader parameter block. Can be NULL.
* \return Status
*/
NTSTATUS
NTAPI
KdDebuggerInitialize0(IN PLOADER_PARAMETER_BLOCK LoaderBlock OPTIONAL)
{
#define CONST_STR_LEN(x) (sizeof(x)/sizeof(x[0]) - 1)
ULONG ComPortNumber = DEFAULT_DEBUG_PORT;
ULONG ComPortBaudRate = DEFAULT_DEBUG_BAUD_RATE;
PUCHAR ComPortAddress = NULL;
PSTR CommandLine, PortString, BaudString;
ULONG Value;
/* Check if we have a LoaderBlock */
if (LoaderBlock)
{
/* Get the Command Line */
CommandLine = LoaderBlock->LoadOptions;
/* Upcase it */
_strupr(CommandLine);
/* Get the port and baud rate */
PortString = strstr(CommandLine, "DEBUGPORT");
BaudString = strstr(CommandLine, "BAUDRATE");
/* Check if we got the DEBUGPORT parameter */
if (PortString)
{
/* Move past the actual string and any spaces */
PortString += CONST_STR_LEN("DEBUGPORT");
while (*PortString == ' ') ++PortString;
/* Skip the equals sign */
if (*PortString) ++PortString;
/* Do we have a serial port? */
if (_strnicmp(PortString, "COM", CONST_STR_LEN("COM")) != 0)
return STATUS_INVALID_PARAMETER;
/* Check for a valid serial port */
PortString += CONST_STR_LEN("COM");
if (*PortString != ':')
{
Value = (ULONG)atol(PortString);
if (Value > MAX_COM_PORTS)
return STATUS_INVALID_PARAMETER;
// if (Value > 0 && Value <= MAX_COM_PORTS)
/* Set the port to use */
ComPortNumber = Value;
}
else
{
/* Retrieve and set its address */
Value = strtoul(PortString + 1, NULL, 0);
if (Value)
{
ComPortNumber = 0;
ComPortAddress = UlongToPtr(Value);
}
}
}
/* Check if we got a baud rate */
if (BaudString)
{
/* Move past the actual string and any spaces */
BaudString += CONST_STR_LEN("BAUDRATE");
while (*BaudString == ' ') ++BaudString;
/* Make sure we have a rate */
if (*BaudString)
{
/* Read and set it */
Value = (ULONG)atol(BaudString + 1);
if (Value) ComPortBaudRate = Value;
}
}
}
if (!ComPortAddress)
ComPortAddress = UlongToPtr(BaseArray[ComPortNumber]);
#ifdef KDDEBUG
/*
* Try to find a free COM port and use it as the KD debugging port.
* NOTE: Inspired by freeldr/comm/rs232.c, Rs232PortInitialize(...)
*/
{
/*
* Enumerate COM ports from the last to the first one, and stop
* when we find a valid port. If we reach the first list element
* (the undefined COM port), no valid port was found.
*/
PUCHAR Address = NULL;
ULONG ComPort;
for (ComPort = MAX_COM_PORTS; ComPort > 0; ComPort--)
{
/* Check if the port exist; skip the KD port */
Address = UlongToPtr(BaseArray[ComPort]);
if ((Address != ComPortAddress) && CpDoesPortExist(Address))
break;
}
if (ComPort != 0 && Address != NULL)
CpInitialize(&KdDebugComPort, Address, DEFAULT_BAUD_RATE);
}
#endif
/* Initialize the port */
return KdpPortInitialize(ComPortAddress, ComPortBaudRate);
}
/******************************************************************************
* \name KdDebuggerInitialize1
* \brief Phase 1 initialization.
* \param [opt] LoaderBlock Pointer to the Loader parameter block. Can be NULL.
* \return Status
*/
NTSTATUS
NTAPI
KdDebuggerInitialize1(IN PLOADER_PARAMETER_BLOCK LoaderBlock OPTIONAL)
{
return STATUS_SUCCESS;
}
VOID
NTAPI
KdpSendByte(IN UCHAR Byte)
{
/* Send the byte */
CpPutByte(&KdComPort, Byte);
}
KDP_STATUS
NTAPI
KdpPollByte(OUT PUCHAR OutByte)
{
USHORT Status;
/* Poll the byte */
Status = CpGetByte(&KdComPort, OutByte, FALSE, FALSE);
switch (Status)
{
case CP_GET_SUCCESS:
return KDP_PACKET_RECEIVED;
case CP_GET_NODATA:
return KDP_PACKET_TIMEOUT;
case CP_GET_ERROR:
default:
return KDP_PACKET_RESEND;
}
}
KDP_STATUS
NTAPI
KdpReceiveByte(OUT PUCHAR OutByte)
{
USHORT Status;
/* Get the byte */
Status = CpGetByte(&KdComPort, OutByte, TRUE, FALSE);
switch (Status)
{
case CP_GET_SUCCESS:
return KDP_PACKET_RECEIVED;
case CP_GET_NODATA:
return KDP_PACKET_TIMEOUT;
case CP_GET_ERROR:
default:
return KDP_PACKET_RESEND;
}
}
KDP_STATUS
NTAPI
KdpPollBreakIn(VOID)
{
KDP_STATUS KdStatus;
UCHAR Byte;
KdStatus = KdpPollByte(&Byte);
if ((KdStatus == KDP_PACKET_RECEIVED) && (Byte == BREAKIN_PACKET_BYTE))
{
return KDP_PACKET_RECEIVED;
}
return KDP_PACKET_TIMEOUT;
}
/* EOF */