sc53c94: fix sending commands to SCSI devices.

devices/common/scsi/sc53c94.cpp

@@ -75,13 +75,14 @@ void Sc53C94::reset_device()
 
 uint8_t Sc53C94::read(uint8_t reg_offset)
 {
-    uint8_t int_status;
+    uint8_t status, int_status;
 
     switch (reg_offset) {
     case Read::Reg53C94::Command:
         return this->cmd_fifo[0];
     case Read::Reg53C94::Status:
-        return this->status;
+        status = bus_obj->test_ctrl_lines(SCSI_CTRL_MSG | SCSI_CTRL_CD | SCSI_CTRL_IO);
+        return (this->status & 0xF8) | status;
     case Read::Reg53C94::Int_Status:
         int_status = this->int_status;
         this->seq_step = 0;
@@ -92,6 +93,8 @@ uint8_t Sc53C94::read(uint8_t reg_offset)
         return this->seq_step;
     case Read::Reg53C94::FIFO_Flags:
         return (this->seq_step << 5) | (this->data_fifo_pos & 0x1F);
+    case Read::Reg53C94::Config_1:
+        return this->config1;
     case Read::Reg53C94::Config_3:
         return this->config3;
     case Read::Reg53C94::Xfer_Cnt_Hi:
@@ -332,6 +335,12 @@ void Sc53C94::sequencer()
     case SeqState::CMD_BEGIN:
         LOG_F(INFO, "CMD_BEGIN reached");
         break;
+    case SeqState::CMD_COMPLETE:
+        this->cmd_steps++;
+        this->int_status |= this->cmd_steps->status;
+        this->update_irq();
+        exec_next_command();
+        break;
     default:
         ABORT_F("SC53C94: unimplemented sequencer state %d", this->cur_state);
     }
@@ -350,16 +359,6 @@ void Sc53C94::update_irq()
 void Sc53C94::notify(ScsiBus* bus_obj, ScsiMsg msg_type, int param)
 {
     switch (msg_type) {
-    case ScsiMsg::BUS_PHASE_CHANGE:
-        switch (param) {
-        case ScsiPhase::COMMAND:
-            this->cur_state = SeqState::CMD_BEGIN;
-            this->sequencer();
-            break;
-        default:
-            LOG_F(WARNING, "SC53C94: ignore bus phase change %d message", param);
-        }
-        break;
     case ScsiMsg::CONFIRM_SEL:
         if (this->target_id == param) {
             // cancel selection timeout timer
@@ -370,6 +369,14 @@ void Sc53C94::notify(ScsiBus* bus_obj, ScsiMsg msg_type, int param)
             LOG_F(WARNING, "SC53C94: ignore invalid selection confirmation message");
         }
         break;
+    case ScsiMsg::SEND_CMD_BEGIN:
+        this->cur_state = SeqState::CMD_BEGIN;
+        this->sequencer();
+        break;
+    case ScsiMsg::SEND_CMD_END:
+        this->cur_state = SeqState::CMD_COMPLETE;
+        this->sequencer();
+        break;
     default:
         LOG_F(WARNING, "SC53C94: ignore notification message, type: %d", msg_type);
     }

devices/common/scsi/scsi.h

@@ -52,9 +52,11 @@ enum : int {
     SELECTION,
     RESELECTION,
     COMMAND,
-    DATA,
+    DATA_IN,
+    DATA_OUT,
     STATUS,
-    MESSAGE,
+    MESSAGE_IN,
+    MESSAGE_OUT,
     RESET,
 };
 };
@@ -62,6 +64,8 @@ enum : int {
 enum ScsiMsg : int {
     CONFIRM_SEL = 1,
     BUS_PHASE_CHANGE,
+    SEND_CMD_BEGIN,
+    SEND_CMD_END,
 };
 
 enum ScsiCommand : int {
@@ -165,6 +169,7 @@ public:
     uint8_t get_data_lines() { return this->data_lines; };
 
     // high-level control/status
+    int  switch_phase(int id, int new_phase);
     bool begin_arbitration(int id);
     bool end_arbitration(int id);
     bool begin_selection(int initiator_id, int target_id, bool atn);

devices/common/scsi/scsi_bus.cpp

@@ -120,6 +120,37 @@ uint16_t ScsiBus::test_ctrl_lines(uint16_t mask)
     return new_state & mask;
 }
 
+int ScsiBus::switch_phase(int id, int new_phase)
+{
+    int old_phase = this->cur_phase;
+
+    // leave the current phase (low-level)
+    switch (old_phase) {
+    case ScsiPhase::COMMAND:
+        this->release_ctrl_line(id, SCSI_CTRL_CD);
+        break;
+    case ScsiPhase::DATA_IN:
+        this->release_ctrl_line(id, SCSI_CTRL_IO);
+        break;
+    }
+
+    // enter new phase (low-level)
+    switch (new_phase) {
+    case ScsiPhase::COMMAND:
+        this->assert_ctrl_line(id, SCSI_CTRL_CD);
+        break;
+    case ScsiPhase::DATA_IN:
+        this->assert_ctrl_line(id, SCSI_CTRL_IO);
+        break;
+    }
+
+    // switch the bus to the new phase (high-level)
+    this->cur_phase = new_phase;
+    change_bus_phase(id);
+
+    return old_phase;
+}
+
 bool ScsiBus::begin_arbitration(int initiator_id)
 {
     if (this->cur_phase == ScsiPhase::BUS_FREE) {
@@ -191,8 +222,9 @@ bool ScsiBus::transfer_command(uint8_t* dst_ptr)
 {
     static uint8_t cmd_to_cdb_length[8] = {6, 10, 10, 6, 6, 12, 6, 6};
 
-    this->cur_phase = ScsiPhase::COMMAND;
-    change_bus_phase(target_id);
+    this->switch_phase(target_id, ScsiPhase::COMMAND);
+
+    this->devices[this->initiator_id]->notify(this, ScsiMsg::SEND_CMD_BEGIN, 0);
 
     // attempt to transfer the shortest Command Description Block (CDB)
     if (!this->devices[this->initiator_id]->send_bytes(dst_ptr, 6)) {
@@ -200,7 +232,7 @@ bool ScsiBus::transfer_command(uint8_t* dst_ptr)
         return false;
     }
 
-    // transfer the remaining CDB
+    // transfer the remaining CDB bytes if any
     int cdb_length = cmd_to_cdb_length[dst_ptr[0] >> 5];
     if (cdb_length > 6) {
         if (!this->devices[this->initiator_id]->send_bytes(dst_ptr + 6, cdb_length - 6)) {
@@ -209,6 +241,8 @@ bool ScsiBus::transfer_command(uint8_t* dst_ptr)
         }
     }
 
+    this->devices[this->initiator_id]->notify(this, ScsiMsg::SEND_CMD_END, 0);
+
     return true;
 }
 

devices/common/scsi/scsidevice.cpp

@@ -49,6 +49,7 @@ void ScsiDevice::notify(ScsiBus* bus_obj, ScsiMsg msg_type, int param)
                         }
                         bus_obj->transfer_command(this->cmd_buf);
                         //this->process_command();
+                        bus_obj->switch_phase(this->scsi_id, ScsiPhase::DATA_IN);
                 });
             }
             break;