KEK/rk05.cpp
2024-04-17 13:44:27 +02:00

250 lines
6.3 KiB
C++

// (C) 2018-2023 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 "rk05.h"
#include "utils.h"
static const char * const regnames[] = {
"RK05_DS drivestatus",
"RK05_ERROR ",
"RK05_CS ctrlstatus",
"RK05_WC word count",
"RK05_BA busaddress",
"RK05_DA disk addrs",
"RK05_DATABUF "
};
rk05::rk05(const std::vector<disk_backend *> & files, bus *const b, std::atomic_bool *const disk_read_acitivity, std::atomic_bool *const disk_write_acitivity) :
b(b),
disk_read_acitivity(disk_read_acitivity),
disk_write_acitivity(disk_write_acitivity)
{
fhs = files;
reset();
}
rk05::~rk05()
{
for(auto fh : fhs)
delete fh;
}
void rk05::reset()
{
memset(registers, 0x00, sizeof registers);
}
uint8_t rk05::readByte(const uint16_t addr)
{
uint16_t v = readWord(addr & ~1);
if (addr & 1)
return v >> 8;
return v;
}
uint16_t rk05::readWord(const uint16_t addr)
{
const int reg = (addr - RK05_BASE) / 2;
if (addr == RK05_DS) { // 0177400
setBit(registers[reg], 11, true); // disk on-line
setBit(registers[reg], 8, true); // sector ok
setBit(registers[reg], 7, true); // drive ready
setBit(registers[reg], 6, true); // seek ready
setBit(registers[reg], 4, true); // heads in position
}
else if (addr == RK05_ERROR) // 0177402
registers[reg] = 0;
else if (addr == RK05_CS) { // 0177404
setBit(registers[reg], 15, false); // clear error
setBit(registers[reg], 14, false); // clear hard error
setBit(registers[reg], 7, true); // controller ready
}
uint16_t vtemp = registers[reg];
if (addr == RK05_CS)
setBit(registers[reg], 0, false); // clear go
DOLOG(debug, false, "RK05 read %s/%o: %06o", reg[regnames], addr, vtemp);
return vtemp;
}
uint32_t rk05::get_bus_address() const
{
return registers[(RK05_BA - RK05_BASE) / 2] | (uint32_t((registers[(RK05_CS - RK05_BASE) / 2] >> 4) & 3) << 16);
}
void rk05::update_bus_address(const uint16_t v)
{
uint32_t org_v = get_bus_address();
org_v += v;
registers[(RK05_BA - RK05_BASE) / 2] = org_v;
registers[(RK05_CS - RK05_BASE) / 2] &= ~(3 << 4);
registers[(RK05_CS - RK05_BASE) / 2] |= ((org_v >> 16) & 3) << 4;
}
void rk05::writeByte(const uint16_t addr, const uint8_t v)
{
uint16_t vtemp = registers[(addr - RK05_BASE) / 2];
update_word(&vtemp, addr & 1, v);
writeWord(addr, vtemp);
}
void rk05::writeWord(const uint16_t addr, uint16_t v)
{
const int reg = (addr - RK05_BASE) / 2;
registers[reg] = v;
if (addr == RK05_CS) {
if (v & 1) { // GO
const int func = (v >> 1) & 7; // FUNCTION
int16_t wc = registers[(RK05_WC - RK05_BASE) / 2];
const size_t reclen = wc < 0 ? (-wc * 2) : wc * 2;
uint16_t temp = registers[(RK05_DA - RK05_BASE) / 2];
uint8_t sector = temp & 15;
uint8_t surface = (temp >> 4) & 1;
int track = (temp >> 4) & 511;
uint16_t cylinder = (temp >> 5) & 255;
uint16_t device = temp >> 13;
const uint32_t diskoff = track * 12 + sector;
const uint32_t diskoffb = diskoff * 512l; // RK05 is high density
const uint32_t memoff = get_bus_address();
registers[(RK05_CS - RK05_BASE) / 2] &= ~(1 << 13); // reset search complete
if (func == 0) { // controller reset
DOLOG(debug, false, "RK05 invoke %d (controller reset)", func);
}
else if (func == 1) { // write
*disk_write_acitivity = true;
DOLOG(debug, false, "RK05 drive %d position sec %d surf %d cyl %d, reclen %zo, WRITE to %o, mem: %o", device, sector, surface, cylinder, reclen, diskoffb, memoff);
uint32_t work_reclen = reclen;
uint32_t work_memoff = memoff;
uint32_t work_diskoffb = diskoffb;
assert(sizeof(xfer_buffer) == 512);
while(work_reclen > 0) {
uint32_t cur = std::min(uint32_t(sizeof xfer_buffer), work_reclen);
work_reclen -= cur;
for(size_t i=0; i<cur; i++)
xfer_buffer[i] = b->readUnibusByte(work_memoff++);
if (!fhs.at(device)->write(work_diskoffb, cur, xfer_buffer))
DOLOG(ll_error, true, "RK05(%d) write error %s", device, strerror(errno));
work_diskoffb += cur;
if (v & 2048)
DOLOG(debug, false, "RK05 inhibit BA increase");
else
update_bus_address(cur);
if (++sector >= 12) {
sector = 0;
if (++surface >= 2) {
surface = 0;
cylinder++;
}
}
}
registers[(RK05_DA - RK05_BASE) / 2] = sector | (surface << 4) | (cylinder << 5);
*disk_write_acitivity = false;
}
else if (func == 2) { // read
*disk_read_acitivity = true;
DOLOG(debug, false, "RK05 drive %d position sec %d surf %d cyl %d, reclen %zo, READ from %o, mem: %o", device, sector, surface, cylinder, reclen, diskoffb, memoff);
uint32_t temp_diskoffb = diskoffb;
uint32_t temp = reclen;
uint32_t p = memoff;
while(temp > 0) {
uint32_t cur = std::min(uint32_t(sizeof xfer_buffer), temp);
if (!fhs.at(device)->read(temp_diskoffb, cur, xfer_buffer)) {
DOLOG(ll_error, true, "RK05 read error %s", strerror(errno));
break;
}
temp_diskoffb += cur;
for(uint32_t i=0; i<cur; i++) {
b->writeUnibusByte(p++, xfer_buffer[i]);
if ((v & 2048) == 0)
update_bus_address(2);
}
temp -= cur;
if (++sector >= 12) {
sector = 0;
if (++surface >= 2) {
surface = 0;
cylinder++;
}
}
}
registers[(RK05_DA - RK05_BASE) / 2] = sector | (surface << 4) | (cylinder << 5);
*disk_read_acitivity = false;
}
else if (func == 4) {
DOLOG(debug, false, "RK05 invoke %d (seek) to %o", func, diskoffb);
registers[(RK05_CS - RK05_BASE) / 2] |= 1 << 13; // search complete
}
else if (func == 7) {
DOLOG(debug, false, "RK05 invoke %d (write lock)", func);
}
else {
DOLOG(debug, false, "RK05 command %d UNHANDLED", func);
}
registers[(RK05_WC - RK05_BASE) / 2] = 0;
registers[(RK05_DS - RK05_BASE) / 2] |= 64; // drive ready
registers[(RK05_CS - RK05_BASE) / 2] |= 128; // control ready
// bit 6, invoke interrupt when done vector address 220, see http://www.pdp-11.nl/peripherals/disk/rk05-info.html
if (v & 64) {
registers[(RK05_DS - RK05_BASE) / 2] &= ~(7l << 13); // store id of the device that caused the interrupt
registers[(RK05_DS - RK05_BASE) / 2] |= device << 13;
b->getCpu()->queue_interrupt(5, 0220);
}
}
}
}