769 lines
16 KiB
C
769 lines
16 KiB
C
/*++
|
||
|
||
Copyright (c) 1990 Microsoft Corporation
|
||
|
||
Module Name:
|
||
|
||
ixkdcom.c
|
||
|
||
Abstract:
|
||
|
||
This module contains a very simply package to do com I/O on machines
|
||
with standard AT com-ports. It is C code derived from the debugger's
|
||
com code. Likely does not work on a PS/2. (Only rewrote the thing
|
||
into C so we wouldn't have to deal with random debugger macros.)
|
||
|
||
Procedures to init a com object, set and query baud rate, output
|
||
character, input character.
|
||
|
||
Author:
|
||
|
||
Bryan M. Willman (bryanwi) 24-Sep-1990
|
||
|
||
Revision History:
|
||
|
||
John Vert (jvert) 12-Jun-1991
|
||
Added ability to check for com-port's existence and hook onto the
|
||
highest com-port available.
|
||
|
||
John Vert (jvert) 19-Jul-1991
|
||
Moved into HAL
|
||
|
||
--*/
|
||
|
||
#include <nthal.h>
|
||
#include <hal.h>
|
||
#include "kdcomp.h"
|
||
#include "kdcom.h"
|
||
#include "inbv.h"
|
||
#define TIMEOUT_COUNT 1024 * 200
|
||
|
||
UCHAR CpReadLsr (PCPPORT, UCHAR);
|
||
|
||
BOOLEAN KdCompDbgPortsPresent = TRUE;
|
||
UCHAR KdCompDbgErrorCount = 0;
|
||
|
||
#define DBG_ACCEPTABLE_ERRORS 25
|
||
|
||
static UCHAR LastLsr, LastMsr;
|
||
|
||
extern pKWriteUchar KdWriteUchar;
|
||
extern pKReadUchar KdReadUchar;
|
||
|
||
|
||
VOID
|
||
CpInitialize (
|
||
PCPPORT Port,
|
||
PUCHAR Address,
|
||
ULONG Rate
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Fill in the com port port object, set the initial baud rate,
|
||
turn on the hardware.
|
||
|
||
Arguments:
|
||
|
||
Port - address of port object
|
||
|
||
Address - port address of the com port
|
||
(CP_COM1_PORT, CP_COM2_PORT)
|
||
|
||
Rate - baud rate (CP_BD_150 ... CP_BD_19200)
|
||
|
||
--*/
|
||
|
||
{
|
||
PUCHAR hwport;
|
||
UCHAR mcr, ier;
|
||
|
||
Port->Address = Address;
|
||
Port->Baud = 0;
|
||
|
||
CpSetBaud(Port, Rate);
|
||
|
||
//
|
||
// Assert DTR, RTS.
|
||
//
|
||
|
||
hwport = Port->Address;
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||
hwport += COM_MCR;
|
||
|
||
mcr = MC_DTRRTS;
|
||
KdWriteUchar(hwport, mcr);
|
||
|
||
hwport = Port->Address;
|
||
hwport += COM_IEN;
|
||
|
||
ier = 0;
|
||
KdWriteUchar(hwport, ier);
|
||
}
|
||
|
||
|
||
|
||
|
||
VOID
|
||
CpSetBaud (
|
||
PCPPORT Port,
|
||
ULONG Rate
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Set the baud rate for the port and record it in the port object.
|
||
|
||
Arguments:
|
||
|
||
Port - address of port object
|
||
|
||
Rate - baud rate (CP_BD_150 ... CP_BD_56000)
|
||
|
||
--*/
|
||
|
||
{
|
||
ULONG divisorlatch;
|
||
PUCHAR hwport;
|
||
UCHAR lcr;
|
||
|
||
//
|
||
// compute the divsor
|
||
//
|
||
|
||
divisorlatch = CLOCK_RATE / Rate;
|
||
|
||
//
|
||
// set the divisor latch access bit (DLAB) in the line control reg
|
||
//
|
||
|
||
hwport = Port->Address;
|
||
hwport += COM_LCR; // hwport = LCR register
|
||
|
||
lcr = KdReadUchar(hwport);
|
||
|
||
lcr |= LC_DLAB;
|
||
KdWriteUchar(hwport, lcr);
|
||
|
||
//
|
||
// set the divisor latch value.
|
||
//
|
||
|
||
hwport = Port->Address;
|
||
hwport += COM_DLM; // divisor latch msb
|
||
KdWriteUchar(hwport, (UCHAR)((divisorlatch >> 8) & 0xff));
|
||
|
||
hwport--; // divisor latch lsb
|
||
KdWriteUchar(hwport, (UCHAR)(divisorlatch & 0xff));
|
||
|
||
|
||
//
|
||
// Set LCR to 3. (3 is a magic number in the original assembler)
|
||
//
|
||
|
||
hwport = Port->Address;
|
||
hwport += COM_LCR;
|
||
KdWriteUchar(hwport, 3);
|
||
|
||
|
||
//
|
||
// Remember the baud rate
|
||
//
|
||
|
||
Port->Baud = Rate;
|
||
}
|
||
|
||
|
||
|
||
USHORT
|
||
CpQueryBaud (
|
||
PCPPORT Port
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Return the last value baud rate was set to.
|
||
|
||
Arguments:
|
||
|
||
Port - address of cpport object which describes the hw port of interest.
|
||
|
||
Return Value:
|
||
|
||
Baud rate. 0 = none has been set.
|
||
|
||
--*/
|
||
|
||
{
|
||
return (USHORT) Port->Baud;
|
||
}
|
||
|
||
VOID
|
||
CpSendModemString (
|
||
PCPPORT Port,
|
||
IN PUCHAR String
|
||
)
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Sends a command string to the modem.
|
||
This is down in order to aid the modem in determining th
|
||
baud rate the local connect is at.
|
||
|
||
Arguments:
|
||
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||
Port - Address of CPPORT
|
||
String - String to send to modem
|
||
|
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--*/
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{
|
||
static ULONG Delay;
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||
TIME_FIELDS CurrentTime;
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UCHAR i;
|
||
ULONG l;
|
||
|
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if (Port->Flags & PORT_SENDINGSTRING)
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return ;
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||
|
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Port->Flags |= PORT_SENDINGSTRING;
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if (!Delay) {
|
||
// see how long 1 second is
|
||
HalQueryRealTimeClock (&CurrentTime);
|
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l = CurrentTime.Second;
|
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while (l == (ULONG) CurrentTime.Second) {
|
||
CpReadLsr(Port, 0);
|
||
HalQueryRealTimeClock (&CurrentTime);
|
||
Delay++;
|
||
}
|
||
Delay = Delay / 3;
|
||
}
|
||
|
||
l = Delay;
|
||
while (*String) {
|
||
HalQueryRealTimeClock (&CurrentTime);
|
||
i = CpReadLsr (Port, 0);
|
||
if (i & COM_OUTRDY) {
|
||
if ((--l) == 0) {
|
||
KdWriteUchar(Port->Address+COM_DAT, *String);
|
||
String++;
|
||
l = Delay;
|
||
}
|
||
}
|
||
if (i & COM_DATRDY)
|
||
KdReadUchar(Port->Address + COM_DAT);
|
||
}
|
||
Port->Flags &= ~PORT_SENDINGSTRING;
|
||
}
|
||
|
||
UCHAR
|
||
CpReadLsr (
|
||
PCPPORT Port,
|
||
UCHAR waiting
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Read LSR byte from specified port. If HAL owns port & display
|
||
it will also cause a debug status to be kept up to date.
|
||
|
||
Handles entering & exiting modem control mode for debugger.
|
||
|
||
Arguments:
|
||
|
||
Port - Address of CPPORT
|
||
|
||
Returns:
|
||
|
||
Byte read from port
|
||
|
||
--*/
|
||
{
|
||
static UCHAR ringflag = 0;
|
||
static UCHAR diagout[3];
|
||
static ULONG diagmsg[3] = { 'TRP ', 'LVO ', 'MRF ' };
|
||
static UCHAR ModemString[] = "\n\rAT\n\r";
|
||
TIME_FIELDS CurrentTime;
|
||
UCHAR lsr, msr, i;
|
||
ULONG diagstr[12];
|
||
|
||
lsr = KdReadUchar(Port->Address + COM_LSR);
|
||
|
||
//
|
||
// Check to see if the port still exists.
|
||
//
|
||
if (lsr == SERIAL_LSR_NOT_PRESENT) {
|
||
|
||
KdCompDbgErrorCount++;
|
||
|
||
if (KdCompDbgErrorCount >= DBG_ACCEPTABLE_ERRORS) {
|
||
KdCompDbgPortsPresent = FALSE;
|
||
KdCompDbgErrorCount = 0;
|
||
}
|
||
return SERIAL_LSR_NOT_PRESENT;
|
||
}
|
||
|
||
if (lsr & COM_PE)
|
||
diagout[0] = 8; // Parity error
|
||
|
||
if (lsr & COM_OE)
|
||
diagout[1] = 8; // Overflow error
|
||
|
||
if (lsr & COM_FE)
|
||
diagout[2] = 8; // Framing error
|
||
|
||
if (lsr & waiting) {
|
||
LastLsr = ~COM_DATRDY | (lsr & COM_DATRDY);
|
||
return lsr;
|
||
}
|
||
|
||
msr = KdReadUchar (Port->Address + COM_MSR);
|
||
|
||
if (Port->Flags & PORT_MODEMCONTROL) {
|
||
if (msr & SERIAL_MSR_DCD) {
|
||
|
||
//
|
||
// In modem control mode with carrier detect
|
||
// Reset carrier lost time
|
||
//
|
||
|
||
Port->Flags |= PORT_NOCDLTIME | PORT_MDM_CD;
|
||
|
||
} else {
|
||
|
||
//
|
||
// In modem control mode, but no carrier detect. After
|
||
// 60 seconds drop out of modem control mode
|
||
//
|
||
|
||
if (Port->Flags & PORT_NOCDLTIME) {
|
||
HalQueryRealTimeClock (&Port->CarrierLostTime);
|
||
Port->Flags &= ~PORT_NOCDLTIME;
|
||
ringflag = 0;
|
||
}
|
||
|
||
HalQueryRealTimeClock (&CurrentTime);
|
||
if (CurrentTime.Minute != Port->CarrierLostTime.Minute &&
|
||
CurrentTime.Second >= Port->CarrierLostTime.Second) {
|
||
|
||
//
|
||
// It's been at least 60 seconds - drop out of
|
||
// modem control mode until next RI
|
||
//
|
||
|
||
Port->Flags &= ~PORT_MODEMCONTROL;
|
||
CpSendModemString (Port, ModemString);
|
||
}
|
||
|
||
if (Port->Flags & PORT_MDM_CD) {
|
||
|
||
//
|
||
// We had a connection - if it's the connection has been
|
||
// down for a few seconds, then send a string to the modem
|
||
//
|
||
|
||
if (CurrentTime.Second < Port->CarrierLostTime.Second)
|
||
CurrentTime.Second += 60;
|
||
|
||
if (CurrentTime.Second > Port->CarrierLostTime.Second + 10) {
|
||
Port->Flags &= ~PORT_MDM_CD;
|
||
CpSendModemString (Port, ModemString);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
if (!(Port->Flags & PORT_SAVED)) {
|
||
return lsr;
|
||
}
|
||
|
||
KdCheckPowerButton();
|
||
|
||
if (lsr == LastLsr && msr == LastMsr) {
|
||
return lsr;
|
||
}
|
||
|
||
ringflag |= (msr & SERIAL_MSR_RI) ? 1 : 2;
|
||
if (ringflag == 3) {
|
||
|
||
//
|
||
// The ring indicate line has toggled
|
||
// Use modem control from now on
|
||
//
|
||
|
||
ringflag = 0;
|
||
Port->Flags |= PORT_MODEMCONTROL | PORT_NOCDLTIME;
|
||
Port->Flags &= ~PORT_MDM_CD;
|
||
|
||
if (Port->Flags & PORT_DEFAULTRATE && Port->Baud != BD_9600) {
|
||
|
||
//
|
||
// Baud rate was never specified switch
|
||
// to 9600 baud as default (for modem usage).
|
||
//
|
||
|
||
InbvDisplayString (MSG_DEBUG_9600);
|
||
CpSetBaud (Port, BD_9600);
|
||
//Port->Flags |= PORT_DISBAUD;
|
||
}
|
||
}
|
||
|
||
for (i=0; i < 3; i++) {
|
||
if (diagout[i]) {
|
||
diagout[i]--;
|
||
diagstr[10-i] = diagmsg[i];
|
||
} else {
|
||
diagstr[10-i] = ' ';
|
||
}
|
||
}
|
||
|
||
diagstr[7] = (LastLsr & COM_DATRDY) ? 'VCR ' : ' ';
|
||
diagstr[6] = (lsr & COM_OUTRDY) ? ' ' : 'DNS ';
|
||
diagstr[5] = (msr & 0x10) ? 'STC ' : ' ';
|
||
diagstr[4] = (msr & 0x20) ? 'RSD ' : ' ';
|
||
diagstr[3] = (msr & 0x40) ? ' IR ' : ' ';
|
||
diagstr[2] = (msr & 0x80) ? ' DC ' : ' ';
|
||
diagstr[1] = (Port->Flags & PORT_MODEMCONTROL) ? 'MDM ' : ' ';
|
||
diagstr[0] = ' ';
|
||
#if 0
|
||
if (Port->Flags & PORT_DISBAUD) {
|
||
switch (Port->Baud) {
|
||
case BD_9600: diagstr[0] = ' 69 '; break;
|
||
case BD_14400: diagstr[0] = 'K41 '; break;
|
||
case BD_19200: diagstr[0] = 'K91 '; break;
|
||
case BD_56000: diagstr[0] = 'K65 '; break;
|
||
}
|
||
}
|
||
#endif
|
||
|
||
//HalpDisplayDebugStatus ((PUCHAR) diagstr, 11*4);
|
||
LastLsr = lsr;
|
||
LastMsr = msr;
|
||
return lsr;
|
||
}
|
||
|
||
|
||
|
||
|
||
VOID
|
||
CpPutByte (
|
||
PCPPORT Port,
|
||
UCHAR Byte
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Write a byte out to the specified com port.
|
||
|
||
Arguments:
|
||
|
||
Port - Address of CPPORT object
|
||
|
||
Byte - data to emit
|
||
|
||
--*/
|
||
|
||
{
|
||
UCHAR msr, lsr;
|
||
|
||
if (KdCompDbgPortsPresent == FALSE) {
|
||
return;
|
||
}
|
||
|
||
//
|
||
// If modem control, make sure DSR, CTS and CD are all set before
|
||
// sending any data.
|
||
//
|
||
|
||
while ((Port->Flags & PORT_MODEMCONTROL) &&
|
||
(msr = KdReadUchar(Port->Address + COM_MSR) & MS_DSRCTSCD) != MS_DSRCTSCD) {
|
||
|
||
//
|
||
// If no CD, and there's a charactor ready, eat it
|
||
//
|
||
|
||
lsr = CpReadLsr (Port, 0);
|
||
if ((msr & MS_CD) == 0 && (lsr & COM_DATRDY) == COM_DATRDY) {
|
||
KdReadUchar(Port->Address + COM_DAT);
|
||
}
|
||
}
|
||
|
||
//
|
||
// Wait for port to not be busy
|
||
//
|
||
|
||
while (!(CpReadLsr(Port, COM_OUTRDY) & COM_OUTRDY)) ;
|
||
|
||
//
|
||
// Send the byte
|
||
//
|
||
|
||
KdWriteUchar(Port->Address + COM_DAT, Byte);
|
||
}
|
||
|
||
USHORT
|
||
CpGetByte (
|
||
PCPPORT Port,
|
||
PUCHAR Byte,
|
||
BOOLEAN WaitForByte
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
Fetch a byte and return it.
|
||
|
||
Arguments:
|
||
|
||
Port - address of port object that describes hw port
|
||
|
||
Byte - address of variable to hold the result
|
||
|
||
WaitForByte - flag indicates wait for byte or not.
|
||
|
||
Return Value:
|
||
|
||
CP_GET_SUCCESS if data returned.
|
||
|
||
CP_GET_NODATA if no data available, but no error.
|
||
|
||
CP_GET_ERROR if error (overrun, parity, etc.)
|
||
|
||
--*/
|
||
|
||
{
|
||
UCHAR lsr;
|
||
UCHAR value;
|
||
ULONG limitcount;
|
||
|
||
//
|
||
// Make sure DTR and CTS are set
|
||
//
|
||
// (What does CTS have to do with reading from a full duplex line???)
|
||
|
||
|
||
//
|
||
// Check to make sure the CPPORT we were passed has been initialized.
|
||
// (The only time it won't be initialized is when the kernel debugger
|
||
// is disabled, in which case we just return.)
|
||
//
|
||
if (Port->Address == NULL) {
|
||
KdCheckPowerButton();
|
||
return(CP_GET_NODATA);
|
||
}
|
||
|
||
if (KdCompDbgPortsPresent == FALSE) {
|
||
|
||
if (CpReadLsr(Port, COM_DATRDY) == SERIAL_LSR_NOT_PRESENT) {
|
||
|
||
return(CP_GET_NODATA);
|
||
} else {
|
||
|
||
CpSetBaud(Port, Port->Baud);
|
||
KdCompDbgPortsPresent = TRUE;
|
||
}
|
||
}
|
||
|
||
limitcount = WaitForByte ? TIMEOUT_COUNT : 1;
|
||
while (limitcount != 0) {
|
||
limitcount--;
|
||
|
||
lsr = CpReadLsr(Port, COM_DATRDY);
|
||
|
||
if (lsr == SERIAL_LSR_NOT_PRESENT) {
|
||
return(CP_GET_NODATA);
|
||
}
|
||
|
||
if ((lsr & COM_DATRDY) == COM_DATRDY) {
|
||
|
||
//
|
||
// Check for errors
|
||
//
|
||
if (lsr & (COM_FE | COM_PE | COM_OE)) {
|
||
*Byte = 0;
|
||
return(CP_GET_ERROR);
|
||
}
|
||
|
||
//
|
||
// fetch the byte
|
||
//
|
||
|
||
value = KdReadUchar(Port->Address + COM_DAT);
|
||
|
||
if (Port->Flags & PORT_MODEMCONTROL) {
|
||
|
||
//
|
||
// Using modem control. If no CD, then skip this byte.
|
||
//
|
||
|
||
if ((KdReadUchar(Port->Address + COM_MSR) & MS_CD) == 0) {
|
||
continue;
|
||
}
|
||
}
|
||
|
||
*Byte = value & (UCHAR)0xff;
|
||
return CP_GET_SUCCESS;
|
||
}
|
||
}
|
||
|
||
LastLsr = 0;
|
||
CpReadLsr (Port, 0);
|
||
return CP_GET_NODATA;
|
||
}
|
||
|
||
|
||
|
||
BOOLEAN
|
||
CpDoesPortExist(
|
||
IN PUCHAR Address
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This routine will attempt to place the port into its
|
||
diagnostic mode. If it does it will twiddle a bit in
|
||
the modem control register. If the port exists this
|
||
twiddling should show up in the modem status register.
|
||
|
||
NOTE: This routine must be called before the device is
|
||
enabled for interrupts, this includes setting the
|
||
output2 bit in the modem control register.
|
||
|
||
This is blatantly stolen from TonyE's code in ntos\dd\serial\serial.c.
|
||
|
||
Arguments:
|
||
|
||
Address - address of hw port.
|
||
|
||
Return Value:
|
||
|
||
TRUE - Port exists. Party on.
|
||
|
||
FALSE - Port doesn't exist. Don't use it.
|
||
|
||
--*/
|
||
|
||
{
|
||
UCHAR OldModemStatus;
|
||
UCHAR ModemStatus;
|
||
BOOLEAN ReturnValue = TRUE;
|
||
|
||
//
|
||
// Save the old value of the modem control register.
|
||
//
|
||
|
||
OldModemStatus = KdReadUchar(Address+COM_MCR);
|
||
|
||
//
|
||
// Set the port into diagnostic mode.
|
||
//
|
||
|
||
KdWriteUchar(
|
||
Address+COM_MCR,
|
||
SERIAL_MCR_LOOP
|
||
);
|
||
|
||
//
|
||
// Bang on it again to make sure that all the lower bits
|
||
// are clear.
|
||
//
|
||
|
||
KdWriteUchar(
|
||
Address+COM_MCR,
|
||
SERIAL_MCR_LOOP
|
||
);
|
||
|
||
//
|
||
// Read the modem status register. The high for bits should
|
||
// be clear.
|
||
//
|
||
|
||
ModemStatus = KdReadUchar(Address+COM_MSR);
|
||
|
||
if (ModemStatus & (SERIAL_MSR_CTS | SERIAL_MSR_DSR |
|
||
SERIAL_MSR_RI | SERIAL_MSR_DCD)) {
|
||
|
||
ReturnValue = FALSE;
|
||
goto AllDone;
|
||
|
||
}
|
||
|
||
//
|
||
// So far so good. Now turn on OUT1 in the modem control register
|
||
// and this should turn on ring indicator in the modem status register.
|
||
//
|
||
|
||
KdWriteUchar(
|
||
Address+COM_MCR,
|
||
(SERIAL_MCR_OUT1 | SERIAL_MCR_LOOP)
|
||
);
|
||
|
||
ModemStatus = KdReadUchar(Address+COM_MSR);
|
||
|
||
if (!(ModemStatus & SERIAL_MSR_RI)) {
|
||
|
||
ReturnValue = FALSE;
|
||
goto AllDone;
|
||
|
||
}
|
||
|
||
AllDone: ;
|
||
|
||
//
|
||
// Put the modem control back into a clean state.
|
||
//
|
||
|
||
KdWriteUchar(
|
||
Address+COM_MCR,
|
||
OldModemStatus
|
||
);
|
||
|
||
return ReturnValue;
|
||
}
|
||
|
||
VOID
|
||
CpWritePortUchar(
|
||
IN PUCHAR Address,
|
||
IN UCHAR Value
|
||
)
|
||
{
|
||
WRITE_PORT_UCHAR(Address, Value);
|
||
} // CpWritePortUchar()
|
||
|
||
UCHAR
|
||
CpReadPortUchar(
|
||
IN PUCHAR Address
|
||
)
|
||
{
|
||
return READ_PORT_UCHAR(Address);
|
||
} // CpReadPortUchar()
|
||
|
||
VOID
|
||
CpWriteRegisterUchar(
|
||
IN PUCHAR Address,
|
||
IN UCHAR Value
|
||
)
|
||
{
|
||
WRITE_REGISTER_UCHAR(Address, Value);
|
||
} // CpWriteRegisterValue()
|
||
|
||
UCHAR
|
||
CpReadRegisterUchar(
|
||
IN PUCHAR Address
|
||
)
|
||
{
|
||
return READ_REGISTER_UCHAR(Address);
|
||
} // CpReadRegisterUchar()
|