Subject: Re: TG3 fix for slow switches (Was: TG3 driver failure on HP 16-way)

From: "David S. Miller" <[email-masked]>
Date: Thu, 6 Jan 2005 19:48:38 -0800

On Fri, 7 Jan 2005 11:17:44 +1100
Darren Williams <[email-masked]> wrote:

> No, if I revert back to an earlier driver the link comes
> up OK printing:
>   tg3: eth0: Link is up at 1000 Mbps, full duplex.
>   tg3: eth0: Flow control is off for TX and off for RX.
> after a short delay. With the current dirver I do not
> see any prinks from tg3_link_report about the state
> of the link.

Is the working verion with Peter's patch applied?

In any case, please try this one instead which is a variant
of the second patch Peter proposed plus some signedness fixes
I've done.

Thanks.

--- ../linus-2.6/drivers/net/tg3.c	2005-01-06 19:23:03.000000000 -0800
+++ drivers/net/tg3.c	2005-01-06 19:22:53.000000000 -0800
@@ -60,8 +60,8 @@
 
 #define DRV_MODULE_NAME		"tg3"
 #define PFX DRV_MODULE_NAME	": "
-#define DRV_MODULE_VERSION	"3.14"
-#define DRV_MODULE_RELDATE	"November 15, 2004"
+#define DRV_MODULE_VERSION	"3.15"
+#define DRV_MODULE_RELDATE	"January 6, 2005"
 
 #define TG3_DEF_MAC_MODE	0
 #define TG3_DEF_RX_MODE		0
@@ -493,7 +493,8 @@
 static int tg3_readphy(struct tg3 *tp, int reg, u32 *val)
 {
 	u32 frame_val;
-	int loops, ret;
+	unsigned int loops;
+	int ret;
 
 	if ((tp->mi_mode & MAC_MI_MODE_AUTO_POLL) != 0) {
 		tw32_f(MAC_MI_MODE,
@@ -512,7 +513,7 @@
 	tw32_f(MAC_MI_COM, frame_val);
 
 	loops = PHY_BUSY_LOOPS;
-	while (loops-- > 0) {
+	while (loops != 0) {
 		udelay(10);
 		frame_val = tr32(MAC_MI_COM);
 
@@ -521,10 +522,11 @@
 			frame_val = tr32(MAC_MI_COM);
 			break;
 		}
+		loops -= 1;
 	}
 
 	ret = -EBUSY;
-	if (loops > 0) {
+	if (loops != 0) {
 		*val = frame_val & MI_COM_DATA_MASK;
 		ret = 0;
 	}
@@ -540,7 +542,8 @@
 static int tg3_writephy(struct tg3 *tp, int reg, u32 val)
 {
 	u32 frame_val;
-	int loops, ret;
+	unsigned int loops;
+	int ret;
 
 	if ((tp->mi_mode & MAC_MI_MODE_AUTO_POLL) != 0) {
 		tw32_f(MAC_MI_MODE,
@@ -558,7 +561,7 @@
 	tw32_f(MAC_MI_COM, frame_val);
 
 	loops = PHY_BUSY_LOOPS;
-	while (loops-- > 0) {
+	while (loops != 0) {
 		udelay(10);
 		frame_val = tr32(MAC_MI_COM);
 		if ((frame_val & MI_COM_BUSY) == 0) {
@@ -566,10 +569,11 @@
 			frame_val = tr32(MAC_MI_COM);
 			break;
 		}
+		loops -= 1;
 	}
 
 	ret = -EBUSY;
-	if (loops > 0)
+	if (loops != 0)
 		ret = 0;
 
 	if ((tp->mi_mode & MAC_MI_MODE_AUTO_POLL) != 0) {
@@ -1557,7 +1561,9 @@
 	bmsr = 0;
 	for (i = 0; i < 100; i++) {
 		tg3_readphy(tp, MII_BMSR, &bmsr);
-		tg3_readphy(tp, MII_BMSR, &bmsr);
+		if (tg3_readphy(tp, MII_BMSR, &bmsr))
+			bmsr = 0;
+
 		if (bmsr & BMSR_LSTATUS)
 			break;
 		udelay(40);
@@ -1640,7 +1646,9 @@
 		tg3_phy_copper_begin(tp);
 
 		tg3_readphy(tp, MII_BMSR, &tmp);
-		tg3_readphy(tp, MII_BMSR, &tmp);
+		if (tg3_readphy(tp, MII_BMSR, &tmp))
+			tmp = 0;
+
 		if (tmp & BMSR_LSTATUS)
 			current_link_up = 1;
 	}
@@ -7209,7 +7217,8 @@
 		u32 bmsr, adv_reg, tg3_ctrl;
 
 		tg3_readphy(tp, MII_BMSR, &bmsr);
-		tg3_readphy(tp, MII_BMSR, &bmsr);
+		if (tg3_readphy(tp, MII_BMSR, &bmsr))
+			bmsr = 0;
 
 		if (bmsr & BMSR_LSTATUS)
 			goto skip_phy_reset;