sc3c94: implement real DMA.

This commit is contained in:
Maxim Poliakovski 2022-11-07 12:31:29 +01:00
parent ca5f81417f
commit a00b87790b
2 changed files with 40 additions and 0 deletions

View File

@ -602,6 +602,35 @@ bool Sc53C94::rcv_data()
return true;
}
void Sc53C94::real_dma_xfer(int direction)
{
bool is_done = false;
if (direction) {
ABORT_F("Sc53C94: real DMA transfers from host to target not implemented yet");
} else { // transfer data from target to host's memory
while (this->xfer_count) {
if (this->data_fifo_pos) {
this->dma_ch->push_data((char*)this->data_fifo, this->data_fifo_pos);
this->xfer_count -= this->data_fifo_pos;
this->data_fifo_pos = 0;
if (!this->xfer_count) {
is_done = true;
this->status |= STAT_TC; // signal zero transfer count
this->cur_state = SeqState::XFER_END;
this->sequencer();
}
}
// see if we need to refill FIFO
if (!this->data_fifo_pos && !is_done) {
this->sequencer();
}
}
}
}
static const DeviceDescription Sc53C94_Descriptor = {
Sc53C94::create, {}, {}
};

View File

@ -29,6 +29,7 @@ along with this program. If not, see <https://www.gnu.org/licenses/>.
#ifndef SC_53C94_H
#define SC_53C94_H
#include <devices/common/dmacore.h>
#include <devices/common/scsi/scsi.h>
#include <devices/common/hwinterrupt.h>
@ -160,6 +161,13 @@ public:
void write(uint8_t reg_offset, uint8_t value);
uint16_t pseudo_dma_read();
// real DMA control
void real_dma_xfer(int direction);
void set_dma_channel(DmaBidirChannel *dma_ch) {
this->dma_ch = dma_ch;
};
// ScsiDevice methods
void notify(ScsiBus* bus_obj, ScsiMsg msg_type, int param);
bool prepare_data() { return false; };
@ -220,6 +228,9 @@ private:
InterruptCtrl* int_ctrl = nullptr;
uint32_t irq_id = 0;
uint8_t irq = 0;
// DMA related stuff
DmaBidirChannel* dma_ch;
};
#endif // SC_53C94_H