Files
Tandy1000_MiSTer/SW/Serial_Server/library/Process.cpp
Aitor Gómez García cd2446dd61 Initial commit
2026-01-06 11:36:45 +01:00

405 lines
10 KiB
C++

//======================================================================
//
// Project: XTIDE Universal BIOS, Serial Port Server
//
// File: process.cpp - Processes commands received over the serial port
//
//
// XTIDE Universal BIOS and Associated Tools
// Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 by XTIDE Universal BIOS Team.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
//
#include "Library.h"
#include <memory.h>
#include <string.h>
#include <stdio.h>
union _buff {
struct {
unsigned char command;
unsigned char driveAndHead;
unsigned char count;
unsigned char sector;
unsigned short cylinder;
} chs;
struct {
unsigned char command;
unsigned char bits24;
unsigned char count;
unsigned char bits00;
unsigned char bits08;
unsigned char bits16;
} lba;
struct {
unsigned char command;
unsigned char driveAndHead;
unsigned char count;
unsigned char scan;
unsigned char port;
unsigned char baud;
} inquire;
struct {
unsigned char command;
unsigned char driveAndHead;
unsigned char count;
unsigned char scan;
unsigned short PackedPortAndBaud;
} inquirePacked;
unsigned char b[514];
unsigned short w[257];
} buff;
#define SERIAL_COMMAND_HEADER 0xa0
#define SERIAL_COMMAND_WRITE 1
#define SERIAL_COMMAND_READWRITE 2
#define SERIAL_COMMAND_RWMASK 3
#define SERIAL_COMMAND_INQUIRE 0
#define SERIAL_COMMAND_MASK 0xe3
#define SERIAL_COMMAND_HEADERMASK 0xe0
#define ATA_COMMAND_LBA 0x40
#define ATA_COMMAND_HEADMASK 0xf
#define ATA_DriveAndHead_Drive 0x10
void logBuff( const char *message, unsigned long buffoffset, unsigned long readto, int verboseLevel )
{
char logBuff[ 514*9 + 10 ];
int logCount;
if( verboseLevel == 5 || (verboseLevel >= 3 && buffoffset == readto) )
{
if( verboseLevel == 3 && buffoffset > 11 )
logCount = 11;
else
logCount = buffoffset;
for( int t = 0; t < logCount; t++ )
sprintf( &logBuff[t*9], "[%3d:%02x] ", t, buff.b[t] );
if( logCount != buffoffset )
sprintf( &logBuff[logCount*9], "... " );
log( 3, "%s%s", message, logBuff );
}
}
void processRequests( SerialAccess *serial, Image *image0, Image *image1, int timeoutEnabled, int verboseLevel )
{
unsigned char workCommand;
int workOffset, workCount;
unsigned long mylba;
unsigned long readto;
unsigned long buffoffset;
unsigned long lasttick;
unsigned short crc;
unsigned long GetTime_Timeout_Local;
unsigned long len;
Image *img;
unsigned long cyl, sect, head;
unsigned long perfTimer;
unsigned char lastScan;
GetTime_Timeout_Local = GetTime_Timeout();
buffoffset = 0;
readto = 0;
workCount = workOffset = workCommand = 0;
lastScan = 0;
//
// Floppy disks must come after any hard disks
//
if( (image0 && image0->floppy) && (image1 && !image1->floppy) )
{
img = image0;
image0 = image1;
image1 = img;
}
lasttick = GetTime();
while( (len = serial->readCharacters( &buff.b[buffoffset], (readto ? readto-buffoffset : 1) )) )
{
buffoffset += len;
//
// For debugging, look at the incoming packet
//
if( verboseLevel >= 3 )
logBuff( " Received: ", buffoffset, readto, verboseLevel );
if( timeoutEnabled && readto && GetTime() > lasttick + GetTime_Timeout_Local )
{
log( 1, "Timeout waiting on data from client, aborting previous command" );
workCount = workOffset = workCommand = 0;
readto = 0;
if( len <= 8 && (buff.b[buffoffset-len] & SERIAL_COMMAND_HEADERMASK) == SERIAL_COMMAND_HEADER )
{
// assume that we are at the front of a new command
//
memcpy( &buff.b[0], &buff.b[buffoffset-len], len );
buffoffset = len;
readto = 8;
// fall through to normal processing
}
else if( len == 1 )
{
// one new character, treat it like any other new character received, discarding the buffer
//
buff.b[0] = buff.b[buffoffset-1];
buffoffset = 1;
// fall through to normal processing
}
else
{
// discard even the newly received data and start listening anew
//
buffoffset = 0;
continue;
}
}
lasttick = GetTime();
//
// No work currently to do, look at each character as they come in...
//
if( !readto )
{
if( (buff.b[0] & SERIAL_COMMAND_HEADERMASK) == SERIAL_COMMAND_HEADER )
{
//
// Found our command header byte to start a commnad sequence, read the next 7 and evaluate
//
readto = 8;
continue;
}
else
{
//
// Spurious characters, discard
//
if( verboseLevel >= 2 )
{
if( buff.b[0] >= 0x20 && buff.b[0] <= 0x7e )
log( 2, "Spurious: [%d:%c]", buff.b[0], buff.b[0] );
else
log( 2, "Spurious: [%d]", buff.b[0] );
}
buffoffset = 0;
continue;
}
}
//
// Partial packet received, keep reading...
//
if( readto && buffoffset < readto )
continue;
//
// Read 512 bytes from serial port, only one command reads that many characters: Write Sector
//
if( buffoffset == readto && readto == 514 )
{
buffoffset = readto = 0;
if( (crc = checksum( &buff.w[0], 256 )) != buff.w[256] )
{
log( 0, "Bad Write Sector Checksum" );
continue;
}
if( img->readOnly )
{
log( 1, "Attempt to write to read-only image" );
continue;
}
img->seekSector( mylba + workOffset );
img->writeSector( &buff.w[0] );
//
// Echo back the CRC
//
if( !serial->writeCharacters( &buff.w[256], 2 ) )
break;
workOffset++;
workCount--;
if( workCount )
readto = 1; // looking for continuation ACK
}
//
// 8 byte command received, or a continuation of the previous command
//
else if( (buffoffset == readto && readto == 8) ||
(buffoffset == readto && readto == 1 && workCount) )
{
buffoffset = readto = 0;
if( workCount )
{
if( verboseLevel > 1 )
log( 2, " Continuation: Offset=%u, Checksum=%04x", workOffset-1, buff.w[256] );
//
// Continuation...
//
if( buff.b[0] != (workCount-0) )
{
log( 0, "Continue Fault: Received=%d, Expected=%d", buff.b[0], workCount );
workCount = 0;
continue;
}
}
else
{
//
// New Command...
//
if( (crc = checksum( &buff.w[0], 3 )) != buff.w[3] )
{
log( 0, "Bad Command Checksum: %02x %02x %02x %02x %02x %02x %02x %02x, Checksum=%04x",
buff.b[0], buff.b[1], buff.b[2], buff.b[3], buff.b[4], buff.b[5], buff.b[6], buff.b[7], crc);
continue;
}
img = (buff.inquire.driveAndHead & ATA_DriveAndHead_Drive) ? image1 : image0;
workCommand = buff.chs.command & SERIAL_COMMAND_RWMASK;
if( (workCommand != SERIAL_COMMAND_INQUIRE) && (buff.chs.driveAndHead & ATA_COMMAND_LBA) )
{
mylba = ((((unsigned long) buff.lba.bits24) & ATA_COMMAND_HEADMASK) << 24)
| (((unsigned long) buff.lba.bits16) << 16)
| (((unsigned long) buff.lba.bits08) << 8)
| ((unsigned long) buff.lba.bits00);
}
else
{
cyl = buff.chs.cylinder;
sect = buff.chs.sector;
head = (buff.chs.driveAndHead & ATA_COMMAND_HEADMASK);
mylba = img ? (((cyl*img->head + head)*img->sect) + sect-1) : 0;
}
workOffset = 0;
workCount = buff.chs.count;
if( verboseLevel > 0 )
{
const char *comStr = (workCommand & SERIAL_COMMAND_WRITE ? "Write" : "Read");
if( workCommand == SERIAL_COMMAND_INQUIRE )
log( 1, "Inquire %d: Client Port=0x%x, Client Baud=%s", img == image0 ? 0 : 1,
((unsigned short) buff.inquire.port) << 2,
baudRateMatchDivisor( buff.inquire.baud )->display );
else if( buff.chs.driveAndHead & ATA_COMMAND_LBA )
log( 1, "%s %d: LBA=%u, Count=%u", comStr, img == image0 ? 0 : 1,
mylba, workCount );
else
log( 1, "%s %d: Cylinder=%u, Sector=%u, Head=%u, Count=%u, LBA=%u", comStr, img == image0 ? 0 : 1,
cyl, sect, head, workCount, mylba );
}
if( !img )
{
log( 1, " No slave drive provided" );
workCount = 0;
continue;
}
if( (workCommand & SERIAL_COMMAND_WRITE) && img->readOnly )
{
log( 1, " Write attempt to Read Only disk" );
workCount = 0;
continue;
}
if( verboseLevel > 0 && workCount > 100 )
perfTimer = GetTime();
}
if( workCount && (workCommand == (SERIAL_COMMAND_WRITE | SERIAL_COMMAND_READWRITE)) )
{
//
// Write command... Setup to receive a sector
//
readto = 514;
}
else
{
//
// Inquire command...
//
if( workCommand == SERIAL_COMMAND_INQUIRE )
{
unsigned char localScan;
if( serial->speedEmulation &&
buff.inquire.baud != serial->baudRate->divisor )
{
log( 1, " Ignoring Inquire with wrong baud rate" );
workCount = 0;
continue;
}
localScan = buff.inquire.scan; // need to do this before the call to
// img->respondInquire, as it will clear the buff
img->respondInquire( &buff.w[0], buff.inquirePacked.PackedPortAndBaud,
serial->baudRate,
((unsigned short) buff.inquire.port) << 2,
(img == image1 && lastScan) || buff.inquire.scan );
lastScan = localScan;
}
//
// Read command...
//
else
{
img->seekSector( mylba + workOffset );
img->readSector( &buff.w[0] );
lastScan = 0;
}
buff.w[256] = checksum( &buff.w[0], 256 );
if( !serial->writeCharacters( &buff.w[0], 514 ) )
break;
if( verboseLevel >= 3 )
logBuff( " Sending: ", 514, 514, verboseLevel );
workCount--;
workOffset++;
if( workCount )
readto = 1; // looking for continuation ACK
}
}
if( workCount == 0 && workOffset > 100 )
log( 1, " Performance: %.2lf bytes per second", (512.0 * workOffset) / (GetTime() - perfTimer) * 1000.0 );
}
}