Skip site navigation (1)Skip section navigation (2) 
Date:      Fri, 30 May 2014 16:44:04 +0000 (UTC)
From:      Hans Petter Selasky <hselasky@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   svn commit: r266892 - head/sys/dev/usb/controller
Message-ID:  <201405301644.s4UGi43p054926@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help 
Author: hselasky
Date: Fri May 30 16:44:03 2014
New Revision: 266892
URL: http://svnweb.freebsd.org/changeset/base/266892

Log:
  It appears the ISP/SAF1761 sometimes is busy when reading the status
  word of the PTD and simply returns a value of zero. Retry a few times
  before giving up.
  
  Sponsored by:	DARPA, AFRL

Modified:
  head/sys/dev/usb/controller/saf1761_otg.c

Modified: head/sys/dev/usb/controller/saf1761_otg.c
==============================================================================
--- head/sys/dev/usb/controller/saf1761_otg.c	Fri May 30 15:46:10 2014	(r266891)
+++ head/sys/dev/usb/controller/saf1761_otg.c	Fri May 30 16:44:03 2014	(r266892)
@@ -291,11 +291,23 @@ saf1761_host_channel_free(struct saf1761
 }
 
 static uint32_t
-saf1761_peek_host_memory_le_4(struct saf1761_otg_softc *sc, uint32_t offset)
+saf1761_peek_host_status_le_4(struct saf1761_otg_softc *sc, uint32_t offset)
 {
-	SAF1761_WRITE_LE_4(sc, SOTG_MEMORY_REG, offset);
-	SAF1761_90NS_DELAY(sc);	/* read prefetch time is 90ns */
-	return (SAF1761_READ_LE_4(sc, offset));
+	uint32_t x = 0;
+	while (1) {
+		uint32_t retval;
+
+		SAF1761_WRITE_LE_4(sc, SOTG_MEMORY_REG, offset);
+		SAF1761_90NS_DELAY(sc);	/* read prefetch time is 90ns */
+		retval = SAF1761_READ_LE_4(sc, offset);
+		if (retval != 0)
+			return (retval);
+		if (++x == 8) {
+			DPRINTF("STAUS is zero at offset 0x%x\n", offset);
+			break;
+		}
+	}
+	return (0);
 }
 
 static void
@@ -415,9 +427,7 @@ saf1761_host_setup_tx(struct saf1761_otg
 	if (td->channel < SOTG_HOST_CHANNEL_MAX) {
 		pdt_addr = SOTG_PTD(td->channel);
 
-		status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
-		if (status == 0)
-			status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
+		status = saf1761_peek_host_status_le_4(sc, pdt_addr + SOTG_PTD_DW3);
 
 		DPRINTFN(5, "STATUS=0x%08x\n", status);
 
@@ -487,9 +497,7 @@ saf1761_host_bulk_data_rx(struct saf1761
 
 		pdt_addr = SOTG_PTD(td->channel);
 
-		status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
-		if (status == 0)
-			status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
+		status = saf1761_peek_host_status_le_4(sc, pdt_addr + SOTG_PTD_DW3);
 
 		DPRINTFN(5, "STATUS=0x%08x\n", status);
 
@@ -591,9 +599,7 @@ saf1761_host_bulk_data_tx(struct saf1761
 
 		pdt_addr = SOTG_PTD(td->channel);
 
-		status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
-		if (status == 0)
-			status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
+		status = saf1761_peek_host_status_le_4(sc, pdt_addr + SOTG_PTD_DW3);
 
 		DPRINTFN(5, "STATUS=0x%08x\n", status);
 
@@ -681,9 +687,7 @@ saf1761_host_intr_data_rx(struct saf1761
 
 		pdt_addr = SOTG_PTD(td->channel);
 
-		status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
-		if (status == 0)
-			status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
+		status = saf1761_peek_host_status_le_4(sc, pdt_addr + SOTG_PTD_DW3);
 
 		DPRINTFN(5, "STATUS=0x%08x\n", status);
 
@@ -788,9 +792,7 @@ saf1761_host_intr_data_tx(struct saf1761
 
 		pdt_addr = SOTG_PTD(td->channel);
 
-		status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
-		if (status == 0)
-			status = saf1761_peek_host_memory_le_4(sc, pdt_addr + SOTG_PTD_DW3);
+		status = saf1761_peek_host_status_le_4(sc, pdt_addr + SOTG_PTD_DW3);
 
 		DPRINTFN(5, "STATUS=0x%08x\n", status);

Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201405301644.s4UGi43p054926>