From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: [net-next-2.6 PATCH] e1000: allow option to limit number of descriptors down to 48 per ring Date: Mon, 19 Jul 2010 16:43:47 -0700 Message-ID: <20100719234219.13875.90302.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, gospo@redhat.com, bphilips@novell.com, Alexander Duyck , Jeff Kirsher To: davem@davemloft.net Return-path: Received: from qmta13.emeryville.ca.mail.comcast.net ([76.96.27.243]:43570 "EHLO qmta13.emeryville.ca.mail.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757358Ab0GSXoI (ORCPT ); Mon, 19 Jul 2010 19:44:08 -0400 Sender: netdev-owner@vger.kernel.org List-ID: From: Alexander Duyck This change makes it possible to limit the number of descriptors down to 48 per ring. The reason for this change is to address a variation on hardware errata 10 for 82546GB in which descriptors will be lost if more than 32 descriptors are fetched and the PCI-X MRBC is 512. Signed-off-by: Alexander Duyck Tested-by: Emil Tantilov Signed-off-by: Jeff Kirsher --- drivers/net/e1000/e1000.h | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/e1000/e1000.h b/drivers/net/e1000/e1000.h index 40b62b4..65298a6 100644 --- a/drivers/net/e1000/e1000.h +++ b/drivers/net/e1000/e1000.h @@ -86,12 +86,12 @@ struct e1000_adapter; /* TX/RX descriptor defines */ #define E1000_DEFAULT_TXD 256 #define E1000_MAX_TXD 256 -#define E1000_MIN_TXD 80 +#define E1000_MIN_TXD 48 #define E1000_MAX_82544_TXD 4096 #define E1000_DEFAULT_RXD 256 #define E1000_MAX_RXD 256 -#define E1000_MIN_RXD 80 +#define E1000_MIN_RXD 48 #define E1000_MAX_82544_RXD 4096 #define E1000_MIN_ITR_USECS 10 /* 100000 irq/sec */