kdcom.c

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/*
 * COPYRIGHT:       GPL, see COPYING in the top level directory
 * PROJECT:         ReactOS kernel
 * FILE:            drivers/base/kdgdb/kdcom.c
 * PURPOSE:         COM port functions for the kernel debugger.
 */

#include "kdgdb.h"

#include <cportlib/cportlib.h>
#include <arc/arc.h>
#include <stdlib.h>
#include <ndk/halfuncs.h>

/* Serial debug connection */
#define DEFAULT_DEBUG_PORT      2 /* COM2 */
#define DEFAULT_DEBUG_COM1_IRQ  4 /* COM1 IRQ */
#define DEFAULT_DEBUG_COM2_IRQ  3 /* COM2 IRQ */
#define DEFAULT_DEBUG_BAUD_RATE 115200 /* 115200 Baud */

#define DEFAULT_BAUD_RATE   19200

#if defined(_M_IX86) || defined(_M_AMD64)
const ULONG BaseArray[] = {0, 0x3F8, 0x2F8, 0x3E8, 0x2E8};
#elif defined(_M_PPC)
const ULONG BaseArray[] = {0, 0x800003F8};
#elif defined(_M_MIPS)
const ULONG BaseArray[] = {0, 0x80006000, 0x80007000};
#elif defined(_M_ARM)
const ULONG BaseArray[] = {0, 0xF1012000};
#else
#error Unknown architecture
#endif

#define MAX_COM_PORTS   (sizeof(BaseArray) / sizeof(BaseArray[0]) - 1)

/* GLOBALS ********************************************************************/

CPPORT KdComPort;
ULONG  KdComPortIrq = 0; // Not used at the moment.
#ifdef KDDEBUG
CPPORT KdDebugComPort;
#endif

/* DEBUGGING ******************************************************************/

#ifdef KDDEBUG
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 ULONG ComPortNumber,
                  IN ULONG ComPortBaudRate)
{
    NTSTATUS Status;

    Status = CpInitialize(&KdComPort,
                          UlongToPtr(BaseArray[ComPortNumber]),
                          ComPortBaudRate);
    if (!NT_SUCCESS(Status))
    {
        return STATUS_INVALID_PARAMETER;
    }
    else
    {
        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)
{
    ULONG ComPortNumber   = DEFAULT_DEBUG_PORT;
    ULONG ComPortBaudRate = DEFAULT_DEBUG_BAUD_RATE;

    PCHAR CommandLine, PortString, BaudString, IrqString;
    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");
        IrqString  = strstr(CommandLine, "IRQ");

        /* Check if we got the /DEBUGPORT parameter */
        if (PortString)
        {
            /* Move past the actual string, to reach the port*/
            PortString += strlen("DEBUGPORT");

            /* Now get past any spaces and skip the equal sign */
            while (*PortString == ' ') PortString++;
            PortString++;

            /* Do we have a serial port? */
            if (strncmp(PortString, "COM", 3) != 0)
            {
                return STATUS_INVALID_PARAMETER;
            }

            /* Check for a valid Serial Port */
            PortString += 3;
            Value = atol(PortString);
            if (Value >= sizeof(BaseArray) / sizeof(BaseArray[0]))
            {
                return STATUS_INVALID_PARAMETER;
            }

            /* Set the port to use */
            ComPortNumber = Value;
       }

        /* Check if we got a baud rate */
        if (BaudString)
        {
            /* Move past the actual string, to reach the rate */
            BaudString += strlen("BAUDRATE");

            /* Now get past any spaces */
            while (*BaudString == ' ') BaudString++;

            /* And make sure we have a rate */
            if (*BaudString)
            {
                /* Read and set it */
                Value = atol(BaudString + 1);
                if (Value) ComPortBaudRate = Value;
            }
        }

        /* Check Serial Port Settings [IRQ] */
        if (IrqString)
        {
            /* Move past the actual string, to reach the rate */
            IrqString += strlen("IRQ");

            /* Now get past any spaces */
            while (*IrqString == ' ') IrqString++;

            /* And make sure we have an IRQ */
            if (*IrqString)
            {
                /* Read and set it */
                Value = atol(IrqString + 1);
                if (Value) KdComPortIrq = Value;
            }
        }
    }

#ifdef KDDEBUG
    /*
     * Try to find a free COM port and use it as the KD debugging port.
     * NOTE: Inspired by reactos/boot/freeldr/freeldr/comm/rs232.c, Rs232PortInitialize(...)
     */
    {
    /*
     * Start enumerating COM ports from the last one to the first one,
     * and break when we find a valid port.
     * If we reach the first element of the list, the invalid COM port,
     * then it means that no valid port was found.
     */
    ULONG ComPort;
    for (ComPort = MAX_COM_PORTS; ComPort > 0; ComPort--)
    {
        /* Check if the port exist; skip the KD port */
        if ((ComPort != ComPortNumber) && CpDoesPortExist(UlongToPtr(BaseArray[ComPort])))
            break;
    }
    if (ComPort != 0)
        CpInitialize(&KdDebugComPort, UlongToPtr(BaseArray[ComPort]), DEFAULT_BAUD_RATE);
    }
#endif

    /* Initialize the port */
    return KdpPortInitialize(ComPortNumber, 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);
}

KDSTATUS
NTAPI
KdpPollByte(OUT PUCHAR OutByte)
{
    /* Poll the byte */
    if (CpGetByte(&KdComPort, OutByte, FALSE, FALSE) == CP_GET_SUCCESS)
    {
        return KdPacketReceived;
    }
    else
    {
        return KdPacketTimedOut;
    }
}

KDSTATUS
NTAPI
KdpReceiveByte(_Out_ PUCHAR OutByte)
{
    USHORT CpStatus = CpGetByte(&KdComPort, OutByte, TRUE, FALSE);
    /* Get the byte */
    if (CpStatus == CP_GET_SUCCESS)
    {
        return KdPacketReceived;
    }

    return KdPacketTimedOut;
}

KDSTATUS
NTAPI
KdpPollBreakIn(VOID)
{
    KDSTATUS KdStatus;
    UCHAR Byte;

    KdStatus = KdpPollByte(&Byte);
    if (KdStatus == KdPacketReceived)
    {
        if (Byte == 0x03)
        {
            KDDBGPRINT("BreakIn Polled.\n");
            return KdPacketReceived;
        }
        else if (Byte == '$')
        {
            /* GDB tried to send a new packet. N-ack it. */
            KdpSendByte('-');
        }
    }
    return KdPacketTimedOut;
}

/* EOF */