m-labs · Nov 19, 2011 · Nov 19, 2011 · Nov 19, 2011 · Nov 19, 2011 · Nov 19, 2011
Showing with 124 additions and 69 deletions.

+124 −69 softusb-input/main.c
diff --git a/softusb-input/main.c b/softusb-input/main.c
@@ -1,6 +1,7 @@
 /*
  * Milkymist SoC (USB firmware)
- * Copyright (C) 2007, 2008, 2009, 2010 Sebastien Bourdeauducq
+ * Copyright (C) 2007, 2008, 2009, 2010, 2011 Sebastien Bourdeauducq
+ * Copyright (C) 2011 Werner Almesberger
  *
  * 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
@@ -96,48 +97,71 @@ static void usb_tx(const unsigned char *buf, unsigned char len)
 	while(rio8(SIE_TX_BUSY));
 }
 
-static const char transfer_start[] PROGMEM = "Transfer start: ";
+static inline void usb_ack(void)
+{
+	wio8(SIE_TX_DATA, 0x80); /* send SYNC */
+	while(rio8(SIE_TX_PENDING));
+	wio8(SIE_TX_DATA, USB_PID_ACK); /* send SYNC */
+	while(rio8(SIE_TX_PENDING));
+	wio8(SIE_TX_VALID, 0);
+	while(rio8(SIE_TX_BUSY));
+}
+
+static const char ack_error[] PROGMEM = "ACK: ";
 static const char timeout_error[] PROGMEM = "RX timeout error\n";
 static const char bitstuff_error[] PROGMEM = "RX bitstuff error\n";
 
-static unsigned char usb_rx(unsigned char *buf, unsigned char maxlen)
+#define	WAIT_RX(first, end)					\
+	do {							\
+		unsigned timeout = 0x200;			\
+		while(!rio8(SIE_RX_PENDING)) {			\
+			if(!--timeout)				\
+				goto timeout;			\
+			if(rio8(SIE_RX_ERROR))			\
+				goto error;			\
+			if(!first && !rio8(SIE_RX_ACTIVE))	\
+				goto end;			\
+		}						\
+	} while (0)
+
+
+static char usb_rx_ack(void)
 {
-	unsigned int timeout;
+	unsigned char pid;
 	unsigned char i;
 
-	i = 0;
-	timeout = 0x1ff;
-	while(!rio8(SIE_RX_PENDING)) {
-		if(timeout-- == 0) {
-			print_string(transfer_start);
-			print_string(timeout_error);
-			return 0;
-		}
-		if(rio8(SIE_RX_ERROR)) {
-			print_string(transfer_start);
-			print_string(bitstuff_error);
-			return 0;
-		}
-	}
-	while(1) {
-		timeout = 0x1ff;
-		while(!rio8(SIE_RX_PENDING)) {
-			if(rio8(SIE_RX_ERROR)) {
-				print_string(bitstuff_error);
-				return 0;
-			}
-			if(!rio8(SIE_RX_ACTIVE))
-				return i;
-			if(timeout-- == 0) {
-				print_string(timeout_error);
-				return 0;
-			}
-		}
-		if(i == maxlen)
-			return 0;
-		buf[i] = rio8(SIE_RX_DATA);
-		i++;
-	}
+	/* SYNC */
+	WAIT_RX(1, nothing);
+
+	/* PID */
+	WAIT_RX(0, nothing);
+	pid = rio8(SIE_RX_DATA);
+
+	/* wait for idle, or simply time out and fall foward */
+	for(i = 200; i; i--)
+		if(!rio8(SIE_RX_ACTIVE))
+			break;
+
+	if(pid == USB_PID_ACK)
+		return 1;
+	if(pid == USB_PID_NAK)
+		return 0;
+
+	for(i = 200; i; i--)
+		WAIT_RX(0,out);
+out:
+	print_string(ack_error);
+	print_hex(pid);
+	print_char('\n');
+	return -1;
+
+timeout:
+	print_string(timeout_error);
+nothing:
+	return 0;
+error:
+	print_string(bitstuff_error);
+	return 0;
 }
 
 static const char in_reply[] PROGMEM = "IN reply:\n";
@@ -147,41 +171,83 @@ static int usb_in(unsigned addr, unsigned char expected_data,
     unsigned char *buf, unsigned char maxlen)
 {
 	unsigned char in[3];
-	unsigned char ack[1] = { USB_PID_ACK };
-	unsigned char len;
+	unsigned char len = 1;
+	unsigned char i;
 
 	/* send IN */
 	make_usb_token(USB_PID_IN, addr, in);
 	usb_tx(in, 3);
 
-	/* receive DATAx */
-	len = usb_rx(buf, maxlen);
-	if(!len) /* timeout or massive confusion */
-		return 0;
+	/* SYNC */
+	WAIT_RX(1, nothing);
+
+	/* PID */
+	WAIT_RX(0, nothing);
+	buf[0] = rio8(SIE_RX_DATA);
+
+	if(buf[0] == expected_data)
+		goto receive;
+	if(buf[0] == USB_PID_DATA0 || buf[0] == USB_PID_DATA1)
+		goto ignore;
 	if(buf[0] == USB_PID_NAK)
 		return 0;
-	if(buf[0] != USB_PID_DATA0 && buf[0] != USB_PID_DATA1) {
-		print_string(in_reply);
-		dump_hex(buf, len);
-		return -1;
+
+	/* unknown packet: try to receive for debug purposes, then dump */
+
+	while(len != maxlen) {
+		WAIT_RX(0, fail);
+		buf[len++] = rio8(SIE_RX_DATA);
 	}
+fail:
+	print_string(in_reply);
+	dump_hex(buf, len);
+	return -1;
 
-	/* send ACK */
-	usb_tx(ack, 1);
-	if(buf[0] == expected_data)
-		return len;
+	/* bad sequence bit: wait until packet has arrived, then ack */
 
+ignore:
+	for(i = 200; i; i--)
+		WAIT_RX(0, ignore_eop);
+	goto complain; /* this doesn't stop - just quit silently */
+ignore_eop:
+	usb_ack();
+complain:
 	print_string(datax_mismatch);
 	return 0;
+
+	/* receive the rest of the (good) packet */
+
+receive:
+	while(1) {
+		WAIT_RX(0, eop);
+		if(len == maxlen)
+			goto discard;
+		buf[len++] = rio8(SIE_RX_DATA);
+	}
+eop:
+	usb_ack();
+	return len;
+
+discard:
+	for(i = 200; i; i--)
+		WAIT_RX(0, nothing);
+nothing:
+	return 0;
+
+timeout:
+	print_string(timeout_error);
+	return 0;
+
+error:
+	print_string(bitstuff_error);
+	return 0;
 }
 
 static const char out_reply[] PROGMEM = "OUT/DATA reply:\n";
 
 static char usb_out(unsigned addr, const unsigned char *buf, unsigned char len)
 {
 	unsigned char out[3];
-	unsigned char ack[11];
-	unsigned char got;
 
 	/* send OUT */
 	make_usb_token(USB_PID_OUT, addr, out);
@@ -191,15 +257,7 @@ static char usb_out(unsigned addr, const unsigned char *buf, unsigned char len)
 	usb_tx(buf, len);
 
 	/* receive ACK */
-	got = usb_rx(ack, 11);
-	if(got == 1 && ack[0] == USB_PID_ACK)
-		return 1;
-	if (!got || ack[0] == USB_PID_NAK) /* timeout or NAK */
-		return 0;
-
-	print_string(out_reply);
-	dump_hex(ack, got);
-	return -1;
+	return usb_rx_ack();
 }
 
 struct setup_packet {
@@ -215,8 +273,7 @@ static inline unsigned char toggle(unsigned char old)
 	return old ^ USB_PID_DATA0 ^ USB_PID_DATA1;
 }
 
-static const char control_failed[] PROGMEM = "Control transfer failed:\n";
-static const char setup_reply[] PROGMEM = "SETUP reply:\n";
+static const char setup_ack[] PROGMEM = "SETUP not ACKed\n";
 
 static int control_transfer(unsigned char addr, struct setup_packet *p,
     char out, unsigned char *payload, int maxlen)
@@ -244,11 +301,8 @@ wio8(SIE_SEL_TX, 3);
 wio8(SIE_SEL_TX, 2);
 #endif
 	/* get ACK token from device */
-	rxlen = usb_rx(usb_buffer, 11);
-	if((rxlen != 1) || (usb_buffer[0] != USB_PID_ACK)) {
-		print_string(control_failed);
-		print_string(setup_reply);
-		dump_hex(usb_buffer, rxlen);
+	if(usb_rx_ack() != 1) {
+		print_string(setup_ack);
 		return -1;
 	}
 
@@ -385,6 +439,7 @@ static void check_discon(struct port_status *p, char name)
 	if(discon) {
 		print_string(disconnect); print_char(name); print_char('\n');
 		p->state = PORT_STATE_DISCONNECTED;
+		p->keyboard.ep = p->mouse.ep = 0;
 	}
 }