netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Matt Carlson" <mcarlson@broadcom.com>
To: davem@davemloft.net
Cc: netdev@vger.kernel.org, andy@greyhouse.net
Subject: [PATCH 02/20] tg3: Fix 5906 transmit hangs
Date: Mon, 2 Nov 2009 16:23:27 -0800	[thread overview]
Message-ID: <1257211991.21986@xw6200> (raw)

The 5906 has trouble with fragments that are less than 8 bytes in size.
This patch works around the problem by pivoting the 5906's transmit
routine to tg3_start_xmit_dma_bug() and introducing a new SHORT_DMA_BUG
flag that enables code to detect and react to the problematic condition.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
---
 drivers/net/tg3.c |   26 +++++++++++++++++++-------
 drivers/net/tg3.h |    1 +
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index da80825..a7a582e 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -5393,7 +5393,7 @@ static netdev_tx_t tg3_start_xmit_dma_bug(struct sk_buff *skb,
 	mss = 0;
 	if ((mss = skb_shinfo(skb)->gso_size) != 0) {
 		struct iphdr *iph;
-		int tcp_opt_len, ip_tcp_len, hdr_len;
+		u32 tcp_opt_len, ip_tcp_len, hdr_len;
 
 		if (skb_header_cloned(skb) &&
 		    pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
@@ -5424,8 +5424,10 @@ static netdev_tx_t tg3_start_xmit_dma_bug(struct sk_buff *skb,
 								 IPPROTO_TCP,
 								 0);
 
-		if ((tp->tg3_flags2 & TG3_FLG2_HW_TSO) ||
-		    (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5705)) {
+		if (tp->tg3_flags2 & TG3_FLG2_HW_TSO_2)
+			mss |= hdr_len << 9;
+		else if ((tp->tg3_flags2 & TG3_FLG2_HW_TSO_1) ||
+			 GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5705) {
 			if (tcp_opt_len || iph->ihl > 5) {
 				int tsflags;
 
@@ -5460,6 +5462,9 @@ static netdev_tx_t tg3_start_xmit_dma_bug(struct sk_buff *skb,
 
 	would_hit_hwbug = 0;
 
+	if ((tp->tg3_flags3 & TG3_FLG3_SHORT_DMA_BUG) && len <= 8)
+		would_hit_hwbug = 1;
+
 	if ((tp->tg3_flags3 & TG3_FLG3_4G_DMA_BNDRY_BUG) &&
 	    tg3_4g_overflow_test(mapping, len))
 		would_hit_hwbug = 1;
@@ -5489,6 +5494,10 @@ static netdev_tx_t tg3_start_xmit_dma_bug(struct sk_buff *skb,
 
 			tnapi->tx_buffers[entry].skb = NULL;
 
+			if ((tp->tg3_flags3 & TG3_FLG3_SHORT_DMA_BUG) &&
+			    len <= 8)
+				would_hit_hwbug = 1;
+
 			if ((tp->tg3_flags3 & TG3_FLG3_4G_DMA_BNDRY_BUG) &&
 			    tg3_4g_overflow_test(mapping, len))
 				would_hit_hwbug = 1;
@@ -12625,8 +12634,12 @@ static int __devinit tg3_get_invariants(struct tg3 *tp)
 	}
 
 	if (!(tp->tg3_flags3 & TG3_FLG3_5755_PLUS)) {
-		tp->tg3_flags3 |= TG3_FLG3_4G_DMA_BNDRY_BUG;
-		tp->tg3_flags3 |= TG3_FLG3_40BIT_DMA_LIMIT_BUG;
+		if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5906)
+			tp->tg3_flags3 |= TG3_FLG3_SHORT_DMA_BUG;
+		else {
+			tp->tg3_flags3 |= TG3_FLG3_4G_DMA_BNDRY_BUG;
+			tp->tg3_flags3 |= TG3_FLG3_40BIT_DMA_LIMIT_BUG;
+		}
 	}
 
 	if (!(tp->tg3_flags2 & TG3_FLG2_5705_PLUS) ||
@@ -13987,8 +14000,7 @@ static int __devinit tg3_init_one(struct pci_dev *pdev,
 		goto err_out_iounmap;
 	}
 
-	if ((tp->tg3_flags3 & TG3_FLG3_5755_PLUS) ||
-	    GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5906)
+	if (tp->tg3_flags3 & TG3_FLG3_5755_PLUS)
 		dev->netdev_ops = &tg3_netdev_ops;
 	else
 		dev->netdev_ops = &tg3_netdev_ops_dma_bug;
diff --git a/drivers/net/tg3.h b/drivers/net/tg3.h
index b603810..a5568a1 100644
--- a/drivers/net/tg3.h
+++ b/drivers/net/tg3.h
@@ -2761,6 +2761,7 @@ struct tg3 {
 #define TG3_FLG3_ENABLE_RSS		0x00020000
 #define TG3_FLG3_4G_DMA_BNDRY_BUG	0x00080000
 #define TG3_FLG3_40BIT_DMA_LIMIT_BUG	0x00100000
+#define TG3_FLG3_SHORT_DMA_BUG		0x00200000
 
 	struct timer_list		timer;
 	u16				timer_counter;
-- 
1.6.4.4



                 reply	other threads:[~2009-11-03  1:33 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1257211991.21986@xw6200 \
    --to=mcarlson@broadcom.com \
    --cc=andy@greyhouse.net \
    --cc=davem@davemloft.net \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).