KEK/rl02.cpp
folkert van heusden 4eb557cbc5
RL02 serialization
2024-04-25 20:04:27 +02:00

379 lines
9.2 KiB
C++

// (C) 2018-2024 by Folkert van Heusden
// Released under MIT license
#include <errno.h>
#include <string.h>
#include "bus.h"
#include "cpu.h"
#include "error.h"
#include "gen.h"
#include "log.h"
#include "rl02.h"
#include "utils.h"
static const char * const regnames[] = {
"control status",
"bus address",
"disk address",
"multipurpose"
};
static const char * const commands[] = {
"no-op",
"write check",
"get status",
"seek",
"read header",
"write data",
"read data",
"read data w/o header check"
};
rl02::rl02(const std::vector<disk_backend *> & files, bus *const b, std::atomic_bool *const disk_read_activity, std::atomic_bool *const disk_write_activity) :
b(b),
disk_read_activity (disk_read_activity),
disk_write_activity(disk_write_activity)
{
fhs = files;
reset();
}
rl02::~rl02()
{
for(auto fh : fhs)
delete fh;
}
void rl02::reset()
{
memset(registers, 0x00, sizeof registers );
memset(xfer_buffer, 0x00, sizeof xfer_buffer);
memset(mpr, 0x00, sizeof mpr );
track = 0;
head = 0;
sector = 0;
}
#if IS_POSIX
json_t *rl02::serialize() const
{
json_t *j = json_object();
json_t *j_backends = json_array();
for(auto & dbe: fhs)
json_array_append(j_backends, dbe->serialize());
json_object_set(j, "backends", j_backends);
for(int regnr=0; regnr<4; regnr++)
json_object_set(j, format("register-%d", regnr).c_str(), json_integer(registers[regnr]));
for(int mprnr=0; mprnr<3; mprnr++)
json_object_set(j, format("mpr-%d", mprnr).c_str(), json_integer(mpr[mprnr]));
json_object_set(j, "track", json_integer(track));
json_object_set(j, "head", json_integer(head));
json_object_set(j, "sector", json_integer(sector));
return j;
}
rl02 *rl02::deserialize(const json_t *const j, bus *const b)
{
std::vector<disk_backend *> backends;
json_t *j_backends = json_object_get(j, "backends");
for(size_t i=0; i<json_array_size(j_backends); i++)
backends.push_back(disk_backend::deserialize(json_array_get(j_backends, i)));
rl02 *r = new rl02(backends, b, nullptr, nullptr);
for(int regnr=0; regnr<4; regnr++)
r->registers[regnr] = json_integer_value(json_object_get(j, format("register-%d", regnr).c_str()));
for(int mprnr=0; mprnr<3; mprnr++)
r->mpr[mprnr] = json_integer_value(json_object_get(j, format("mpr-%d", mprnr).c_str()));
r->track = json_integer_value(json_object_get(j, "track" ));
r->head = json_integer_value(json_object_get(j, "head" ));
r->sector = json_integer_value(json_object_get(j, "sector"));
return r;
}
#endif
uint8_t rl02::readByte(const uint16_t addr)
{
uint16_t v = readWord(addr & ~1);
if (addr & 1)
return v >> 8;
return v;
}
uint16_t rl02::readWord(const uint16_t addr)
{
const int reg = (addr - RL02_BASE) / 2;
if (addr == RL02_CSR) { // control status
setBit(registers[reg], 0, true); // drive ready (DRDY)
setBit(registers[reg], 7, true); // controller ready (CRDY)
}
uint16_t value = 0;
if (addr == RL02_MPR) { // multi purpose register
value = mpr[0];
mpr[0] = mpr[1];
mpr[1] = mpr[2];
mpr[2] = 0;
}
else {
value = registers[reg];
}
DOLOG(debug, false, "RL02: read \"%s\"/%o: %06o", regnames[reg], addr, value);
return value;
}
void rl02::writeByte(const uint16_t addr, const uint8_t v)
{
uint16_t vtemp = registers[(addr - RL02_BASE) / 2];
if (addr & 1) {
vtemp &= ~0xff00;
vtemp |= v << 8;
}
else {
vtemp &= ~0x00ff;
vtemp |= v;
}
writeWord(addr, vtemp);
}
uint32_t rl02::get_bus_address() const
{
return (registers[(RL02_BAR - RL02_BASE) / 2] | (uint32_t((registers[(RL02_CSR - RL02_BASE) / 2] >> 4) & 3) << 16)) & ~1;
}
void rl02::update_bus_address(const uint32_t a)
{
registers[(RL02_BAR - RL02_BASE) / 2] = a;
registers[(RL02_CSR - RL02_BASE) / 2] &= ~(3 << 4);
registers[(RL02_CSR - RL02_BASE) / 2] |= ((a >> 16) & 3) << 4;
}
uint32_t rl02::calc_offset() const
{
return (rl02_sectors_per_track * track * 2 + head * rl02_sectors_per_track + sector) * rl02_bytes_per_sector;
}
void rl02::update_dar()
{
registers[(RL02_DAR - RL02_BASE) / 2] = (sector & 63) | (head << 6) | (track << 7);
}
void rl02::writeWord(const uint16_t addr, uint16_t v)
{
const int reg = (addr - RL02_BASE) / 2;
DOLOG(debug, false, "RL02: write \"%s\"/%06o: %06o", regnames[reg], addr, v);
registers[reg] = v;
if (addr == RL02_CSR) { // control status
const uint8_t command = (v >> 1) & 7;
const bool do_exec = !(v & 128);
int device = (v >> 8) & 3;
DOLOG(debug, false, "RL02: device %d, set command %d, exec: %d (%s)", device, command, do_exec, commands[command]);
bool do_int = false;
if (size_t(device) >= fhs.size()) {
DOLOG(info, false, "RL02: PDP11/70 is accessing a not-attached virtual disk %d", device);
registers[(RL02_CSR - RL02_BASE) / 2] |= (1 << 10) | (1 << 15);
do_int = true;
}
else if (command == 2) { // get status
mpr[0] = 5 /* lock on */ | (1 << 3) /* brush home */ | (1 << 4) /* heads over disk */ | (head << 6) | (1 << 7) /* RL02 */;
mpr[1] = mpr[0];
}
else if (command == 3) { // seek
uint16_t temp = registers[(RL02_DAR - RL02_BASE) / 2];
int cylinder_count = (temp >> 7) * (temp & 4 ? 1 : -1);
int16_t new_track = track + cylinder_count;
if (new_track < 0)
new_track = 0;
else if (new_track >= rl02_track_count)
new_track = rl02_track_count - 1;
DOLOG(debug, false, "RL02: device %d, seek from cylinder %d to %d (distance: %d, DAR: %06o)", device, track, new_track, cylinder_count, temp);
track = new_track;
// update_dar();
do_int = true;
}
else if (command == 4) { // read header
mpr[0] = (sector & 63) | (head << 6) | (track << 7);
mpr[1] = 0; // zero
mpr[2] = 0; // TODO: CRC
DOLOG(debug, false, "RL02: device %d, read header [cylinder: %d, head: %d, sector: %d] %06o", device, track, head, sector, mpr[0]);
do_int = true;
}
else if (command == 5) { // write data
if (disk_write_activity)
*disk_write_activity = true;
uint32_t memory_address = get_bus_address();
uint32_t count = (65536l - registers[(RL02_MPR - RL02_BASE) / 2]) * 2;
if (count == 65536)
count = 0;
uint16_t temp = registers[(RL02_DAR - RL02_BASE) / 2];
sector = temp & 63;
head = (temp >> 6) & 1;
track = temp >> 7;
uint32_t temp_disk_offset = calc_offset();
DOLOG(debug, false, "RL02: device %d, write %d bytes (dec) to %d (dec) from %06o (oct) [cylinder: %d, head: %d, sector: %d]", device, count, temp_disk_offset, memory_address, track, head, sector);
while(count > 0) {
uint32_t cur = std::min(uint32_t(sizeof xfer_buffer), count);
for(uint32_t i=0; i<cur;) {
// BA and MPR are increased by 2
xfer_buffer[i++] = b->readUnibusByte(memory_address++);
xfer_buffer[i++] = b->readUnibusByte(memory_address++);
// update_bus_address(memory_address);
mpr[0]++;
}
if (!fhs.at(device)->write(temp_disk_offset, cur, xfer_buffer)) {
DOLOG(ll_error, true, "RL02: write error, device %d, disk offset %u, read size %u, cylinder %d, head %d, sector %d", device, temp_disk_offset, cur, track, head, sector);
break;
}
mpr[0] += count / 2;
temp_disk_offset += cur;
count -= cur;
sector++;
if (sector >= rl02_sectors_per_track) {
sector = 0;
head++;
if (head >= 2) {
head = 0;
track++;
}
}
}
do_int = true;
if (disk_write_activity)
*disk_write_activity = false;
}
else if (command == 6 || command == 7) { // read data / read data without header check
if (disk_read_activity)
*disk_read_activity = true;
uint32_t memory_address = get_bus_address();
uint32_t count = (65536l - registers[(RL02_MPR - RL02_BASE) / 2]) * 2;
if (count == 65536)
count = 0;
uint16_t temp = registers[(RL02_DAR - RL02_BASE) / 2];
sector = temp & 63;
head = (temp >> 6) & 1;
track = temp >> 7;
uint32_t temp_disk_offset = calc_offset();
DOLOG(debug, false, "RL02: device %d, read %d bytes (dec) from %d (dec) to %06o (oct) [cylinder: %d, head: %d, sector: %d]", device, count, temp_disk_offset, memory_address, track, head, sector);
// update_dar();
while(count > 0) {
uint32_t cur = std::min(uint32_t(sizeof xfer_buffer), count);
if (!fhs.at(device)->read(temp_disk_offset, cur, xfer_buffer)) {
DOLOG(ll_error, true, "RL02: read error, device %d, disk offset %u, read size %u, cylinder %d, head %d, sector %d", device, temp_disk_offset, cur, track, head, sector);
break;
}
for(uint32_t i=0; i<cur;) {
// BA and MPR are increased by 2
b->writeUnibusByte(memory_address++, xfer_buffer[i++]);
b->writeUnibusByte(memory_address++, xfer_buffer[i++]);
// update_bus_address(memory_address);
mpr[0]++;
}
temp_disk_offset += cur;
count -= cur;
sector++;
if (sector >= rl02_sectors_per_track) {
sector = 0;
head++;
if (head >= 2) {
head = 0;
track++;
}
}
// update_dar();
}
do_int = true;
if (disk_read_activity)
*disk_read_activity = false;
}
else {
DOLOG(warning, false, "RL02: command %d not implemented", command);
}
if (do_int) {
if (registers[(RL02_CSR - RL02_BASE) / 2] & 64) { // interrupt enable?
DOLOG(debug, false, "RL02: triggering interrupt");
b->getCpu()->queue_interrupt(5, 0160);
}
}
}
}