dingusppc/devices/common/ata/atapibasedevice.cpp
2023-11-22 17:35:14 +01:00

205 lines
6.7 KiB
C++

/*
DingusPPC - The Experimental PowerPC Macintosh emulator
Copyright (C) 2018-23 divingkatae and maximum
(theweirdo) spatium
(Contact divingkatae#1017 or powermax#2286 on Discord for more info)
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 3 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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
/** @file Basic ATAPI interface emulation. */
#include <devices/common/ata/atabasedevice.h>
#include <devices/common/ata/atapibasedevice.h>
#include <devices/common/ata/atadefs.h>
#include <endianswap.h>
#include <loguru.hpp>
#include <cinttypes>
#include <cstring>
using namespace ata_interface;
AtapiBaseDevice::AtapiBaseDevice(const std::string name)
: AtaBaseDevice(name, DEVICE_TYPE_ATAPI) {
}
void AtapiBaseDevice::device_set_signature() {
this->r_int_reason = 1; // shadows ATA r_sect_count
this->r_sect_num = 1; // required for protocol identification in OF 2.x
this->r_dev_head = 0;
// set ATAPI protocol signature
this->r_byte_count = 0xEB14;
this->r_status_save = this->r_status; // for restoring on the first command
this->r_status = 0;
}
uint16_t AtapiBaseDevice::read(const uint8_t reg_addr) {
switch (reg_addr) {
case ATA_Reg::DATA:
if (has_data()) {
uint16_t ret_data = get_data();
this->xfer_cnt -= 2;
if (this->xfer_cnt <= 0) {
this->r_status &= ~DRQ;
if ((this->r_int_reason & ATAPI_Int_Reason::IO) &&
!(this->r_int_reason & ATAPI_Int_Reason::CoD)
) {
if (this->data_available()) {
this->r_status &= ~DRQ;
this->r_status |= BSY;
this->update_intrq(1); // Is this going to work here? The interrupt happens before returning ret_data.
}
else if (this->status_expected) {
this->present_status();
}
}
}
return ret_data;
} else {
return 0xFFFFU;
}
case ATA_Reg::ERROR:
return this->r_error;
case ATAPI_Reg::INT_REASON:
return this->r_int_reason;
case ATA_Reg::SEC_NUM:
return this->r_sect_num;
case ATAPI_Reg::BYTE_COUNT_LO:
return this->r_byte_count & 0xFFU;
case ATAPI_Reg::BYTE_COUNT_HI:
return (this->r_byte_count >> 8) & 0xFFU;
case ATA_Reg::DEVICE_HEAD:
return this->r_dev_head;
case ATA_Reg::STATUS:
this->update_intrq(0);
return this->r_status;
case ATA_Reg::ALT_STATUS:
if (this->r_status & BSY && this->data_available()) {
this->r_byte_count = this->request_data();
this->data_out_phase();
}
return this->r_status;
default:
LOG_F(WARNING, "Attempted to read unknown register: %x", reg_addr);
return 0;
}
}
void AtapiBaseDevice::write(const uint8_t reg_addr, const uint16_t value) {
switch (reg_addr) {
case ATA_Reg::DATA:
if (has_data()) {
*this->data_ptr++ = BYTESWAP_16(value);
this->xfer_cnt -= 2;
if (this->xfer_cnt <= 0) {
this->r_status &= ~DRQ;
if (this->r_int_reason & CoD) {
this->perform_packet_command();
}
}
}
break;
case ATA_Reg::FEATURES:
this->r_features = value;
break;
case ATA_Reg::SEC_COUNT:
case ATA_Reg::SEC_NUM:
break; // unused in ATAPI, NoOp them here for compatibility
case ATAPI_Reg::BYTE_COUNT_LO:
this->r_byte_count = (this->r_byte_count & 0xFF00U) | (value & 0xFFU);
break;
case ATAPI_Reg::BYTE_COUNT_HI:
this->r_byte_count = (this->r_byte_count & 0xFFU) | ((value & 0xFFU) << 8);
break;
case ATA_Reg::DEVICE_HEAD:
this->r_dev_head = value;
break;
case ATA_Reg::COMMAND:
this->r_command = value;
if (is_selected() || this->r_command == DIAGNOSTICS) {
perform_command();
}
break;
case ATA_Reg::DEV_CTRL:
this->device_control(value);
break;
default:
LOG_F(WARNING, "Attempted to write unknown IDE register: %x", reg_addr);
}
}
int AtapiBaseDevice::perform_command() {
this->r_error &= ~ATA_Error::ABRT;
this->r_status &= ~ATA_Status::ERR;
this->r_status |= BSY;
switch (this->r_command) {
case ATAPI_PACKET:
this->data_ptr = (uint16_t *)this->cmd_pkt;
this->xfer_cnt = sizeof(this->cmd_pkt);
this->r_int_reason &= ~ATAPI_Int_Reason::IO; // host->device
this->r_int_reason |= ATAPI_Int_Reason::CoD; // command packet
this->r_status |= DRQ;
this->r_status &= ~BSY;
break;
case ATAPI_IDFY_DEV:
std::memset(this->data_buf, 0, 512);
this->data_buf[0] = 0xC0;
this->data_buf[1] = 0x85;
this->data_ptr = (uint16_t *)this->data_buf;
this->xfer_cnt = 512;
this->status_expected = false;
this->data_out_phase();
break;
case SET_FEATURES:
switch (this->r_features) {
case 3: // set transfer mode
LOG_F(INFO, "%s: xfer_type=0x%X, mode=0x%X", this->name.c_str(),
this->r_sect_count >> 3, this->r_sect_count & 7);
break;
default:
LOG_F(ERROR, "%s: unsupported subcommand 0x%X in SET_FEATURES",
this->name.c_str(), this->r_features);
this->r_error |= ATA_Error::ABRT;
this->r_status |= ATA_Status::ERR;
}
this->r_status &= ~BSY;
this->update_intrq(1);
break;
default:
LOG_F(ERROR, "%s: unsupported command 0x%X", this->name.c_str(), this->r_command);
this->r_error |= ATA_Error::ABRT;
this->r_status |= ATA_Status::ERR;
}
return 0;
}
void AtapiBaseDevice::data_out_phase() {
this->r_int_reason |= ATAPI_Int_Reason::IO; // device->host
this->r_int_reason &= ~ATAPI_Int_Reason::CoD; // data
this->signal_data_ready();
}
void AtapiBaseDevice::present_status() {
this->r_int_reason |= ATAPI_Int_Reason::IO;
this->r_int_reason |= ATAPI_Int_Reason::CoD;
this->r_status &= ~DRQ;
this->r_status &= ~BSY;
this->update_intrq(1);
}