From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: b44: Reset due to FIFO overflow. Date: Mon, 28 Jun 2010 11:13:14 +0200 Message-ID: <1277716394.4235.235.camel@edumazet-laptop> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org To: James Courtier-Dutton Return-path: Received: from mail-wy0-f174.google.com ([74.125.82.174]:48038 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750834Ab0F1JNT (ORCPT ); Mon, 28 Jun 2010 05:13:19 -0400 Received: by wyb38 with SMTP id 38so1583313wyb.19 for ; Mon, 28 Jun 2010 02:13:17 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: Le lundi 28 juin 2010 =C3=A0 08:41 +0100, James Courtier-Dutton a =C3=A9= crit : > Hi, >=20 > Reference: > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/279102 >=20 > I can see this bug and can reproduce it 100% on demand. > The problem seems to be that when the b44 has a incoming FIFO buffer > overflow, it resets the entire card, dis-associates with the access > point and therefore takes some time before it can pass traffic again. > Can anyone point me to some code that would just recover the FIFO > instead of reset the entire card? >=20 > I am a kernel developer, but I don't have any data sheets on this car= d > so was hoping someone with more knowledge of its workings, could help > me. >=20 > I can then test it, and see if it is a good fix or not. >=20 Hi Problem is we dont know if a Receive Fifo overflow is a minor or major indication from b44 chip. A minor indication would be : Chip tells us one or more frame were lost= =2E No special action needed from driver. A major indication (as of current implemented in b44 driver) is : I am completely out of order and need a reset. Please do it. Patch to switch from major to minor indication is easy, but we dont kno= w if its valid or not. diff --git a/drivers/net/b44.h b/drivers/net/b44.h index e1905a4..514dc3a 100644 --- a/drivers/net/b44.h +++ b/drivers/net/b44.h @@ -42,7 +42,7 @@ #define ISTAT_EMAC 0x04000000 /* EMAC Interrupt */ #define ISTAT_MII_WRITE 0x08000000 /* MII Write Interrupt */ #define ISTAT_MII_READ 0x10000000 /* MII Read Interrupt */ -#define ISTAT_ERRORS (ISTAT_DSCE|ISTAT_DATAE|ISTAT_DPE|ISTAT_RDU|ISTA= T_RFO|ISTAT_TFU) +#define ISTAT_ERRORS (ISTAT_DSCE|ISTAT_DATAE|ISTAT_DPE|ISTAT_RDU|ISTA= T_TFU) #define B44_IMASK 0x0024UL /* Interrupt Mask */ #define IMASK_DEF (ISTAT_ERRORS | ISTAT_TO | ISTAT_RX | ISTAT_TX) #define B44_GPTIMER 0x0028UL /* General Purpose Timer */