[SC64][SW] Added USB debug feature (#8)

sw/riscv/build.sh

@@ -1,3 +1,3 @@
 #!/bin/bash
 
-docker run --mount type=bind,src="$(pwd)",target="/workdir" ghcr.io/polprzewodnikowy/sc64env:v1.0 /bin/bash -c "make clean all"
+docker run --mount type=bind,src="$(pwd)",target="/workdir" ghcr.io/polprzewodnikowy/sc64env:v1.0 /bin/bash -c "USER_FLAGS=\"-DDEBUG\" make clean all"

sw/riscv/src/cfg.c

@@ -1,5 +1,6 @@
 #include "cfg.h"
 #include "joybus.h"
+#include "usb.h"
 
 
 #define SAVE_SIZE_EEPROM_4K     (512)
@@ -199,6 +200,37 @@ void process_cfg (void) {
                 cfg_query(args);
                 break;
 
+            case 'S':
+                args[0] = usb_debug_tx_ready();
+                break;
+
+            case 'D':
+                if (!usb_debug_tx_data(args[0], (size_t) args[1])) {
+                    change_scr_bits(CFG_SCR_CMD_ERROR, true);
+                }
+                break;
+
+            case 'A':
+                if (!usb_debug_rx_ready(&args[0], (size_t *) (&args[1]))) {
+                    args[0] = 0;
+                    args[1] = 0;
+                }
+                break;
+
+            case 'F':
+                args[0] = usb_debug_rx_busy();
+                break;
+            
+            case 'E':
+                if (!usb_debug_rx_data(args[0], (size_t) args[1])) {
+                    change_scr_bits(CFG_SCR_CMD_ERROR, true);
+                }
+                break;
+
+            case 'B':
+                usb_debug_reset();
+                break;
+
             default:
                 change_scr_bits(CFG_SCR_CMD_ERROR, true);
                 break;

sw/riscv/src/usb.c

@@ -67,6 +67,7 @@ enum state {
     STATE_ARGS,
     STATE_DATA,
     STATE_RESPONSE,
+    STATE_DEBUG_TX,
 };
 
 struct process {
@@ -76,22 +77,97 @@ struct process {
     uint32_t args[2];
     bool error;
     bool dma_in_progress;
+
+    bool debug_rx_busy;
+    uint32_t debug_rx_address;
+    size_t debug_rx_length;
+
+    bool debug_tx_busy;
+    uint32_t debug_tx_address;
+    size_t debug_tx_length;
 };
 
 static struct process p;
 
 
+bool usb_debug_rx_ready (uint32_t *type, size_t *length) {
+    if (p.state != STATE_DATA || p.cmd != 'D' || p.debug_rx_busy) {
+        return false;
+    }
+
+    *type = p.args[0];
+    *length = (size_t) p.args[1];
+
+    return true;
+}
+
+bool usb_debug_rx_busy (void) {
+    return p.debug_rx_busy;
+}
+
+bool usb_debug_rx_data (uint32_t address, size_t length) {
+    if (p.debug_rx_busy) {
+        return false;
+    }
+
+    p.debug_rx_busy = true;
+    p.debug_rx_address = address;
+    p.debug_rx_length = length;
+
+    return true;
+}
+
+bool usb_debug_tx_ready (void) {
+    return !p.debug_tx_busy;
+}
+
+bool usb_debug_tx_data (uint32_t address, size_t length) {
+    if (p.debug_tx_busy) {
+        return false;
+    }
+
+    p.debug_tx_busy = true;
+    p.debug_tx_address = address;
+    p.debug_tx_length = length;
+
+    return true;
+}
+
+void usb_debug_reset (void) {
+    uint8_t tmp;
+
+    if (p.state == STATE_DATA && p.cmd == 'D') {
+        for (size_t i = 0; i < p.args[1]; i++) {
+            rx_byte(&tmp);
+        }
+        p.args[1] = 0;    
+    }
+    if (p.state == STATE_DEBUG_TX) {
+        p.state = STATE_IDLE;
+    }
+    p.debug_rx_busy = false;
+    p.debug_tx_busy = false;
+
+    USB->SCR = USB_SCR_FLUSH_TX | USB_SCR_FLUSH_RX;
+}
+
+
 void usb_init (void) {
     USB->SCR = USB_SCR_FLUSH_TX | USB_SCR_FLUSH_RX;
 
     p.state = STATE_IDLE;
+    p.debug_rx_busy = false;
+    p.debug_tx_busy = false;
 }
 
 
 void process_usb (void) {
     switch (p.state) {
         case STATE_IDLE:
-            if (rx_word(&p.args[0])) {
+            if (p.debug_tx_busy) {
+                p.state = STATE_DEBUG_TX;
+                p.dma_in_progress = false;
+            } else if (rx_word(&p.args[0])) {
                 if ((p.args[0] & 0xFFFFFF00) == USB_CMD_TOKEN) {
                     p.cmd = p.args[0] & 0xFF;
                     p.counter = 0;
@@ -142,6 +218,22 @@ void process_usb (void) {
                     }
                     break;
 
+                case 'D':
+                    if (!dma_busy() && p.debug_rx_busy && p.args[1] > 0) {
+                        if (!p.dma_in_progress) {
+                            dma_start(p.debug_rx_address, p.debug_rx_length, DMA_ID_USB, DMA_DIR_TO_SDRAM);
+                            p.dma_in_progress = true;
+                        } else {
+                            p.args[1] -= p.debug_rx_length > p.args[1] ? p.args[1] : p.debug_rx_length;
+                            p.dma_in_progress = false;
+                            p.debug_rx_busy = false;
+                        }
+                    }
+                    if (p.args[1] == 0) {
+                        p.state = STATE_IDLE;
+                    }
+                    break;
+
                 default:
                     p.error = true;
                     p.state = STATE_RESPONSE;
@@ -154,5 +246,17 @@ void process_usb (void) {
                 p.state = STATE_IDLE;
             }
             break;
+
+        case STATE_DEBUG_TX:
+            if (!dma_busy()) {
+                if (!p.dma_in_progress) {
+                    dma_start(p.debug_tx_address, p.debug_tx_length, DMA_ID_USB, DMA_DIR_FROM_SDRAM);
+                    p.dma_in_progress = true;
+                } else {
+                    p.debug_tx_busy = false;
+                    p.state = STATE_IDLE;
+                }
+            }
+            break;
     }
 }

sw/riscv/src/usb.h

@@ -5,6 +5,12 @@
 #include "sys.h"
 
 
+bool usb_debug_rx_ready (uint32_t *type, size_t *length);
+bool usb_debug_rx_busy (void);
+bool usb_debug_rx_data (uint32_t address, size_t length);
+bool usb_debug_tx_ready (void);
+bool usb_debug_tx_data (uint32_t address, size_t length);
+void usb_debug_reset (void);
 void usb_init (void);
 void process_usb (void);