From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756831Ab2FNX7x (ORCPT ); Thu, 14 Jun 2012 19:59:53 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:45919 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932108Ab2FNX7r (ORCPT ); Thu, 14 Jun 2012 19:59:47 -0400 Message-Id: <20120614235625.609881878@linuxfoundation.org> User-Agent: quilt/0.60-20.1 Date: Thu, 14 Jun 2012 16:56:42 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Emmanuel Grumbach , Johannes Berg , "John W. Linville" Subject: [ 19/42] iwlwifi: disable the buggy chain extension feature in HW In-Reply-To: <20120614235636.GA5275@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Emmanuel Grumbach commit d012d04e4d6312ea157b6cf19e9689af934f5aa7 upstream. This feature has been reported to be buggy and enabled by default. We therefore need to disable it manually. Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/iwlwifi/iwl-prph.h | 1 + drivers/net/wireless/iwlwifi/iwl-trans-pcie.c | 5 +++++ 2 files changed, 6 insertions(+) --- a/drivers/net/wireless/iwlwifi/iwl-prph.h +++ b/drivers/net/wireless/iwlwifi/iwl-prph.h @@ -224,6 +224,7 @@ #define SCD_TXFACT (SCD_BASE + 0x10) #define SCD_ACTIVE (SCD_BASE + 0x14) #define SCD_QUEUECHAIN_SEL (SCD_BASE + 0xe8) +#define SCD_CHAINEXT_EN (SCD_BASE + 0x244) #define SCD_AGGR_SEL (SCD_BASE + 0x248) #define SCD_INTERRUPT_MASK (SCD_BASE + 0x108) --- a/drivers/net/wireless/iwlwifi/iwl-trans-pcie.c +++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie.c @@ -1128,6 +1128,11 @@ static void iwl_tx_start(struct iwl_tran iwl_write_prph(trans, SCD_DRAM_BASE_ADDR, trans_pcie->scd_bc_tbls.dma >> 10); + /* The chain extension of the SCD doesn't work well. This feature is + * enabled by default by the HW, so we need to disable it manually. + */ + iwl_write_prph(trans, SCD_CHAINEXT_EN, 0); + /* Enable DMA channel */ for (chan = 0; chan < FH_TCSR_CHNL_NUM ; chan++) iwl_write_direct32(trans, FH_TCSR_CHNL_TX_CONFIG_REG(chan),