[PATCH u-boot-marvell 16/29] tools: kwboot: Properly finish xmodem transfer

[Marek Behún]

From: Pali Rohár <pali at kernel.org>

After kwboot sends EOT, BootROM sends back ACK. Add code for handling
this and retry sending EOT on error.

Signed-off-by: Pali Rohár <pali at kernel.org>
[ refactored ]
Signed-off-by: Marek Behún <marek.behun at nic.cz>
---
 tools/kwboot.c | 65 +++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 48 insertions(+), 17 deletions(-)

diff --git a/tools/kwboot.c b/tools/kwboot.c
index 0e60cc8a70..6674a253ff 100644
--- a/tools/kwboot.c
+++ b/tools/kwboot.c
@@ -383,6 +383,28 @@ _is_xm_reply(char c)
 	return c == ACK || c == NAK || c == CAN;
 }
 
+static int
+_xm_reply_to_error(int c) {
+	int rc = -1;
+
+	switch (c) {
+	case ACK:
+		rc = 0;
+		break;
+	case NAK:
+		errno = EBADMSG;
+		break;
+	case CAN:
+		errno = ECANCELED;
+		break;
+	default:
+		errno = EPROTO;
+		break;
+	}
+
+	return rc;
+}
+
 static uint64_t
 _now(void)
 {
@@ -463,24 +485,32 @@ kwboot_xm_sendblock(int fd, struct kwboot_block *block, int allow_non_xm,
 		return -1;
 	}
 
-	rc = -1;
+	return _xm_reply_to_error(c);
+}
 
-	switch (c) {
-	case ACK:
-		rc = 0;
-		break;
-	case NAK:
-		errno = EBADMSG;
-		break;
-	case CAN:
-		errno = ECANCELED;
-		break;
-	default:
-		errno = EPROTO;
-		break;
-	}
+static int
+kwboot_xm_finish(int tty)
+{
+	int rc, retries;
+	char c;
 
-	return rc;
+	retries = 16;
+	do {
+		rc = kwboot_tty_send_char(tty, EOT);
+		if (rc)
+			return rc;
+
+		do {
+			rc = kwboot_tty_recv(tty, &c, 1, blk_rsp_timeo);
+			if (rc) {
+				if (errno != ETIMEDOUT)
+					return rc;
+				c = NAK;
+			}
+		} while (!_is_xm_reply(c) && retries-- > 0);
+	} while (c == NAK && retries-- > 0);
+
+	return _xm_reply_to_error(c);
 }
 
 static int
@@ -557,7 +587,8 @@ kwboot_xmodem(int tty, const void *_img, size_t size)
 	if (rc)
 		return rc;
 
-	return kwboot_tty_send_char(tty, EOT);
+	kwboot_printv("Finishing transfer\n");
+	return kwboot_xm_finish(tty);
 }
 
 static int
-- 
2.31.1