From patchwork Fri Jan 15 10:17:21 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaoqing Pan X-Patchwork-Id: 8039581 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: X-Original-To: patchwork-linux-wireless@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 256259F744 for ; Fri, 15 Jan 2016 10:18:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 193082041B for ; Fri, 15 Jan 2016 10:18:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2165920444 for ; Fri, 15 Jan 2016 10:18:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756376AbcAOKSz (ORCPT ); Fri, 15 Jan 2016 05:18:55 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:36887 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754264AbcAOKSx (ORCPT ); Fri, 15 Jan 2016 05:18:53 -0500 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 4E4C860226; Fri, 15 Jan 2016 10:18:53 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 3CD07605C2; Fri, 15 Jan 2016 10:18:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from smtp.codeaurora.org (unknown [180.166.53.21]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: miaoqing@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id C00F66026A; Fri, 15 Jan 2016 10:18:50 +0000 (UTC) Received: by smtp.codeaurora.org (sSMTP sendmail emulation); Fri, 15 Jan 2016 18:18:45 +0800 From: miaoqing@codeaurora.org To: linville@tuxdriver.com Cc: linux-wireless@vger.kernel.org, ath9k-devel@qca.qualcomm.com, kvalo@qca.qualcomm.com, Miaoqing Pan Subject: [PATCH v2 5/5] ath9k: fix data bus error on ar9300 and ar9580 Date: Fri, 15 Jan 2016 18:17:21 +0800 Message-Id: <1452853041-3674-6-git-send-email-miaoqing@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1452853041-3674-1-git-send-email-miaoqing@codeaurora.org> References: <1452853041-3674-1-git-send-email-miaoqing@codeaurora.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Miaoqing Pan One crash issue be found on ar9300: RTC_RC reg read leads crash, leading the data bus error, due to RTC_RC reg write not happen properly. Warm Reset trigger in continuous beacon stuck for one of the customer for other chip, noticed the MAC was stuck in RTC reset. After analysis noticed DMA did not complete when RTC was put in reset. So, before resetting the MAC need to make sure there are no pending DMA transactions because this reset does not reset all parts of the chip. The 12th and 11th bit of MAC _DMA_CFG register used to do that. 12 cfg_halt_ack 0x0 0 DMA has not yet halted 1 DMA has halted 11 cfg_halt_req 0x0 0 DMA logic operates normally 1 Request DMA logic to stop so software can reset the MAC The Bit [12] of this register indicates when the halt has taken effect or not. the DMA halt IS NOT recoverable; once software sets bit [11] to request a DMA halt, software must wait for bit [12] to be set and reset the MAC. So, the same thing we implemented for ar9580 chip. Signed-off-by: Miaoqing Pan --- drivers/net/wireless/ath/ath9k/hw.c | 10 ++++++++++ drivers/net/wireless/ath/ath9k/reg.h | 4 +++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index 257f46e..e7a3101 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -1368,6 +1368,16 @@ static bool ath9k_hw_set_reset(struct ath_hw *ah, int type) if (ath9k_hw_mci_is_enabled(ah)) ar9003_mci_check_gpm_offset(ah); + /* DMA HALT added to resolve ar9300 and ar9580 bus error during + * RTC_RC reg read + */ + if (AR_SREV_9300(ah) || AR_SREV_9580(ah)) { + REG_SET_BIT(ah, AR_CFG, AR_CFG_HALT_REQ); + ath9k_hw_wait(ah, AR_CFG, AR_CFG_HALT_ACK, AR_CFG_HALT_ACK, + 20 * AH_WAIT_TIMEOUT); + REG_CLR_BIT(ah, AR_CFG, AR_CFG_HALT_REQ); + } + REG_WRITE(ah, AR_RTC_RC, rst_flags); REGWRITE_BUFFER_FLUSH(ah); diff --git a/drivers/net/wireless/ath/ath9k/reg.h b/drivers/net/wireless/ath/ath9k/reg.h index caba54d..c8d35fe 100644 --- a/drivers/net/wireless/ath/ath9k/reg.h +++ b/drivers/net/wireless/ath/ath9k/reg.h @@ -34,8 +34,10 @@ #define AR_CFG_SWRG 0x00000010 #define AR_CFG_AP_ADHOC_INDICATION 0x00000020 #define AR_CFG_PHOK 0x00000100 -#define AR_CFG_CLK_GATE_DIS 0x00000400 #define AR_CFG_EEBS 0x00000200 +#define AR_CFG_CLK_GATE_DIS 0x00000400 +#define AR_CFG_HALT_REQ 0x00000800 +#define AR_CFG_HALT_ACK 0x00001000 #define AR_CFG_PCI_MASTER_REQ_Q_THRESH 0x00060000 #define AR_CFG_PCI_MASTER_REQ_Q_THRESH_S 17