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Diffstat (limited to 'src/devices/machine/fm_scsi.cpp')
-rw-r--r-- | src/devices/machine/fm_scsi.cpp | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/src/devices/machine/fm_scsi.cpp b/src/devices/machine/fm_scsi.cpp new file mode 100644 index 00000000000..d2b8fcd266f --- /dev/null +++ b/src/devices/machine/fm_scsi.cpp @@ -0,0 +1,439 @@ +// license:BSD-3-Clause +// copyright-holders:Barry Rodewald +/* + * + * Implementation of Fujitsu FMR-50, FMR-60 and FM-Towns SCSI hardware + * + * + + info from Toshiya Takeda's e-FMR50 source (the Towns uses the same controller?) + 0xc30 = Data register + 0xc32 = Status register (read) + bit 7 = REQ + bit 6 = I/O + bit 5 = MSG + bit 4 = C/D + bit 3 = BUSY + bit 1 = INT + bit 0 = PERR + 0xc32 = Control register (write) + bit 7 = WEN + bit 6 = IMSK + bit 4 = ATN + bit 2 = SEL + bit 1 = DMAE + bit 0 = RST +*/ +#include "emu.h" +#include "fm_scsi.h" +#include "debugger.h" + +// SCSI input lines (from target) +#define FMSCSI_LINE_REQ 0x80 +#define FMSCSI_LINE_IO 0x40 +#define FMSCSI_LINE_MSG 0x20 +#define FMSCSI_LINE_CD 0x10 +#define FMSCSI_LINE_BSY 0x08 +#define FMSCSI_LINE_EX 0x04 +#define FMSCSI_LINE_INT 0x02 +#define FMSCSI_LINE_PERR 0x01 + +// SCSI output lines (to target) +#define FMSCSI_LINE_WEN 0x80 +#define FMSCSI_LINE_IMSK 0x40 +#define FMSCSI_LINE_RMSK 0x20 +#define FMSCSI_LINE_ATN 0x10 +#define FMSCSI_LINE_WRD 0x08 +#define FMSCSI_LINE_SEL 0x04 +#define FMSCSI_LINE_DMAE 0x02 +#define FMSCSI_LINE_RST 0x01 + +/* + * Device config + */ + +DEFINE_DEVICE_TYPE(FMSCSI, fmscsi_device, "fmscsi", "FM-SCSI") + +/* + * Device + */ + +fmscsi_device::fmscsi_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) + : legacy_scsi_host_adapter(mconfig, FMSCSI, tag, owner, clock), + m_irq_handler(*this), + m_drq_handler(*this) +{ +} + +void fmscsi_device::device_start() +{ + m_input_lines = 0; + m_output_lines = 0; + m_data = 0; + m_command_index = 0; + m_last_id = 0; + m_target = 0; + m_phase = SCSI_PHASE_BUS_FREE; + + m_irq_handler.resolve_safe(); + m_drq_handler.resolve_safe(); + + // allocate read timer + m_transfer_timer = timer_alloc(FUNC(fmscsi_device::update_transfer), this); + m_phase_timer = timer_alloc(FUNC(fmscsi_device::set_phase), this); +} + +void fmscsi_device::device_reset() +{ + m_input_lines = 0; + m_output_lines = 0; + m_data = 0; + m_command_index = 0; + m_last_id = 0; + m_target = 0; + m_result_length = 0; + m_result_index = 0; + stop_transfer(); + set_input_line(FMSCSI_LINE_INT,0); + m_irq_handler(0); + + m_phase = SCSI_PHASE_BUS_FREE; +} + +// get the length of a SCSI command based on it's command byte type +int fmscsi_device::get_scsi_cmd_len(uint8_t cbyte) +{ + int group; + + group = (cbyte>>5) & 7; + + if (group == 0) return 6; + if (group == 1 || group == 2) return 10; + if (group == 5) return 12; + + fatalerror("fmscsi: Unknown SCSI command group %d\n", group); + + // never executed + //return 6; +} + +TIMER_CALLBACK_MEMBER(fmscsi_device::update_transfer) +{ + set_input_line(FMSCSI_LINE_REQ,1); + //logerror("FMSCSI: timer triggered: %i/%i\n",m_result_index,m_result_length); + if(m_output_lines & FMSCSI_LINE_DMAE) + { + m_drq_handler(1); + } +} + +void fmscsi_device::stop_transfer() +{ + m_transfer_timer->adjust(attotime::never); // stop timer + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_STATUS); + if(m_output_lines & FMSCSI_LINE_DMAE) + { + m_drq_handler(0); + } + logerror("FMSCSI: Stopping transfer : (%i/%i)\n",m_result_index,m_result_length); +} + +uint8_t fmscsi_device::fmscsi_data_r(void) +{ + // read from data bus + // ACK is automatic on accessing the data bus, so REQ will go low. + set_input_line(FMSCSI_LINE_REQ,0); + + if(m_phase == SCSI_PHASE_DATAIN) + { + m_data = m_buffer[m_result_index % 512]; + //logerror("FMSCSI: DATAIN phase read data %02x\n",m_data); + m_result_index++; + if(m_result_index % 512 == 0) + read_data(m_buffer,512); // read next sector + + if(m_result_index >= m_result_length) + { + // end of data transfer + stop_transfer(); + } + return m_data; + } + + if(m_phase == SCSI_PHASE_MESSAGE_IN) + { + m_data = 0; // command complete message + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_BUS_FREE); + m_command_index = 0; + return m_data; + } + + if(m_phase == SCSI_PHASE_STATUS) + { + m_data = get_status(); + // no command complete message? + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_MESSAGE_IN); + m_command_index = 0; + //set_input_line(FMSCSI_LINE_REQ,1); // raise REQ yet again + return m_data; + } + + return m_data; +} + +void fmscsi_device::fmscsi_data_w(uint8_t data) +{ + int phase; + + // write to data bus + m_data = data; + //logerror("FMSCSI: data write %02x\n",data); + + // ACK is automatic on accessing the data bus, so REQ will go low. + set_input_line(FMSCSI_LINE_REQ,0); + + if(m_phase == SCSI_PHASE_BUS_FREE) + { + // select target + switch(data & 0x7f) + { + case 0x01: m_target = 0; break; + case 0x02: m_target = 1; break; + case 0x04: m_target = 2; break; + case 0x08: m_target = 3; break; + case 0x10: m_target = 4; break; + } + } + if(m_phase == SCSI_PHASE_DATAOUT) + { + m_buffer[m_result_index % 512] = m_data; + m_result_index++; + if(m_result_index % 512 == 0) + write_data(m_buffer,512); // write buffer to disc + if(m_result_index >= m_result_length) + { + // end of data transfer + m_transfer_timer->adjust(attotime::never); // stop timer + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_STATUS); + if(m_output_lines & FMSCSI_LINE_DMAE) + { + m_drq_handler(0); + } + logerror("FMSCSI: Stopping transfer : (%i/%i)\n",m_result_index,m_result_length); + } + } + if(m_phase == SCSI_PHASE_COMMAND) + { + m_command[m_command_index] = data; + logerror("FMSCSI: writing command byte %02x [%i]\n",data,m_command_index); + m_command_index++; + if(m_command_index >= get_scsi_cmd_len(m_command[0])) + { + // command complete + send_command(m_command,m_command_index); + m_result_length = get_length(); + phase = legacy_scsi_host_adapter::get_phase(); + m_phase_timer->adjust(attotime::from_usec(800),phase); + + logerror("FMSCSI: Command %02x sent, result length = %i\n",m_command[0],m_result_length); + } + else + { + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_COMMAND); + } + } + if(m_phase == SCSI_PHASE_MESSAGE_OUT) + { + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_STATUS); + } +} + +TIMER_CALLBACK_MEMBER(fmscsi_device::set_phase) +{ + m_phase = param; + logerror("FMSCSI: phase set to %i\n",m_phase); + // set input lines accordingly + switch(param) + { + case SCSI_PHASE_BUS_FREE: + set_input_line(FMSCSI_LINE_BSY,0); + set_input_line(FMSCSI_LINE_CD,0); + set_input_line(FMSCSI_LINE_MSG,0); + set_input_line(FMSCSI_LINE_IO,0); + //set_input_line(FMSCSI_LINE_REQ,0); + break; + case SCSI_PHASE_COMMAND: + set_input_line(FMSCSI_LINE_BSY,1); + set_input_line(FMSCSI_LINE_CD,1); + set_input_line(FMSCSI_LINE_MSG,0); + set_input_line(FMSCSI_LINE_IO,0); + set_input_line(FMSCSI_LINE_REQ,1); + break; + case SCSI_PHASE_STATUS: + set_input_line(FMSCSI_LINE_CD,1); + set_input_line(FMSCSI_LINE_MSG,0); + set_input_line(FMSCSI_LINE_IO,1); + set_input_line(FMSCSI_LINE_REQ,1); + break; + case SCSI_PHASE_DATAIN: + set_input_line(FMSCSI_LINE_CD,0); + set_input_line(FMSCSI_LINE_MSG,0); + set_input_line(FMSCSI_LINE_IO,1); + set_input_line(FMSCSI_LINE_REQ,1); + // start transfer timer + m_transfer_timer->adjust(attotime::zero,0,attotime::from_hz(3000000)); // arbitrary value for now + read_data(m_buffer,512); + m_result_index = 0; + logerror("FMSCSI: Starting transfer in (%i)\n",m_result_length); + break; + case SCSI_PHASE_DATAOUT: + set_input_line(FMSCSI_LINE_CD,0); + set_input_line(FMSCSI_LINE_MSG,0); + set_input_line(FMSCSI_LINE_IO,0); + set_input_line(FMSCSI_LINE_REQ,1); + // start transfer timer + m_transfer_timer->adjust(attotime::zero,0,attotime::from_hz(3000000)); // arbitrary value for now + m_result_index = 0; + logerror("FMSCSI: Starting transfer out (%i)\n",m_result_length); + break; + case SCSI_PHASE_MESSAGE_IN: + set_input_line(FMSCSI_LINE_CD,1); + set_input_line(FMSCSI_LINE_MSG,1); + set_input_line(FMSCSI_LINE_IO,1); + set_input_line(FMSCSI_LINE_REQ,1); + break; + case SCSI_PHASE_MESSAGE_OUT: + set_input_line(FMSCSI_LINE_CD,1); + set_input_line(FMSCSI_LINE_MSG,1); + set_input_line(FMSCSI_LINE_IO,0); + set_input_line(FMSCSI_LINE_REQ,1); + break; + } +} + +int fmscsi_device::get_phase(void) +{ + return m_phase; +} + +void fmscsi_device::set_input_line(uint8_t line, uint8_t state) +{ + if(line == FMSCSI_LINE_REQ) + { + if(state != 0 && !(m_input_lines & FMSCSI_LINE_REQ)) // low to high + { + if(m_output_lines & FMSCSI_LINE_IMSK && m_phase != SCSI_PHASE_DATAIN && m_phase != SCSI_PHASE_DATAOUT) + { + set_input_line(FMSCSI_LINE_INT,1); + m_irq_handler(1); + logerror("FMSCSI: IRQ high\n"); + } + } + if(state == 0 && (m_input_lines & FMSCSI_LINE_REQ)) // high to low + { + if(m_output_lines & FMSCSI_LINE_IMSK && m_phase != SCSI_PHASE_DATAIN && m_phase != SCSI_PHASE_DATAOUT) + { + set_input_line(FMSCSI_LINE_INT,0); + m_irq_handler(0); + logerror("FMSCSI: IRQ low\n"); + } + } + } + if(state != 0) + m_input_lines |= line; + else + m_input_lines &= ~line; +// logerror("FMSCSI: input line %02x set to %i\n",line,state); +} + +uint8_t fmscsi_device::get_input_line(uint8_t line) +{ + return m_input_lines & line; +} + +void fmscsi_device::set_output_line(uint8_t line, uint8_t state) +{ + if(line == FMSCSI_LINE_RST && state != 0) + { + device_reset(); + logerror("FMSCSI: reset\n"); + } + + if(line == FMSCSI_LINE_SEL) + { + if(state != 0 && !(m_output_lines & FMSCSI_LINE_SEL)) // low to high transition + { + if (select(m_target)) + { + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_COMMAND); + m_data = 0x08; + } + } + } + + if(line == FMSCSI_LINE_ATN) + { + if(state != 0) + m_phase_timer->adjust(attotime::from_usec(800),SCSI_PHASE_MESSAGE_OUT); + } + + if(state != 0) + m_output_lines |= line; + else + m_output_lines &= ~line; +// logerror("FMSCSI: output line %02x set to %i\n",line,state); +} + +uint8_t fmscsi_device::get_output_line(uint8_t line) +{ + return m_output_lines & line; +} + +uint8_t fmscsi_device::fmscsi_status_r(void) +{ + // status inputs + return m_input_lines; +} + +void fmscsi_device::fmscsi_control_w(uint8_t data) +{ + // control outputs + set_output_line(FMSCSI_LINE_RST,data & FMSCSI_LINE_RST); + set_output_line(FMSCSI_LINE_DMAE,data & FMSCSI_LINE_DMAE); + set_output_line(FMSCSI_LINE_IMSK,data & FMSCSI_LINE_IMSK); + set_output_line(FMSCSI_LINE_ATN,data & FMSCSI_LINE_ATN); + set_output_line(FMSCSI_LINE_WEN,data & FMSCSI_LINE_WEN); + set_output_line(FMSCSI_LINE_SEL,data & FMSCSI_LINE_SEL); + logerror("FMSCSI: control write %02x\n",data); +} + +uint8_t fmscsi_device::fmscsi_r(offs_t offset) +{ + switch(offset & 0x03) + { + case 0x00: + return fmscsi_data_r(); + case 0x01: + return fmscsi_status_r(); + case 0x02: + return 0x80; // Linux uses this port to detect the ability to do word transfers. We'll tell it that it doesn't for now. + default: + logerror("FMSCSI: Unknown read at offset %i\n",offset); + } + return 0; +} + +void fmscsi_device::fmscsi_w(offs_t offset, uint8_t data) +{ + switch(offset & 0x03) + { + case 0x00: + fmscsi_data_w(data); + break; + case 0x01: + fmscsi_control_w(data); + break; + default: + logerror("FMSCSI: Unknown write 0x%02x at offset %i\n",data,offset); + } +} |