From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A39BEC432C0 for ; Wed, 27 Nov 2019 09:59:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F70F2070A for ; Wed, 27 Nov 2019 09:59:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b="RA+u824b" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727080AbfK0J7f (ORCPT ); Wed, 27 Nov 2019 04:59:35 -0500 Received: from first.geanix.com ([116.203.34.67]:40536 "EHLO first.geanix.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726240AbfK0J7e (ORCPT ); Wed, 27 Nov 2019 04:59:34 -0500 Received: from [192.168.100.95] (unknown [95.138.208.137]) by first.geanix.com (Postfix) with ESMTPSA id ECD98932E2; Wed, 27 Nov 2019 09:55:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=geanix.com; s=first; t=1574848548; bh=pCBMs1+4TyKgx4Yf4XCivsPLFaR7wIHPML0iaaZtTIo=; h=Subject:To:Cc:References:From:Date:In-Reply-To; b=RA+u824bqYGCua2R5aq1z0Y0toxOngDc1Wa6ao9/XOvRCWedchdZff1W9TtkMGL+a Qfc3ZjkDqQY7Vnw8K0tHPrsJRsqWac0tUZM/STvg9RrFwL4GtDGWgYYTrHNE+9Ktz9 B68NKgPT/k/GbdznZXMf4VX7eL0l9uiYAKQZx/X7SuQNw1mGecyDp5kGCXtz+Rr3sl oToyWAFNHeDHN4fLtNAh7fSCqPBTQtNb6J5dIWtmnKEaqn3fgPgQ9yqZhmS8W+/yar e/MUGpked3UhZvwCl8evJZJ5EN8/NZ/gpk+qusbF8Ymj4XSISNGYOULHuyEV2fdD0v 4Vf3Qb+uyWlIg== Subject: Re: [PATCH V2 3/4] can: flexcan: change the way of stop mode acknowledgment To: Joakim Zhang , "mkl@pengutronix.de" , "linux-can@vger.kernel.org" Cc: dl-linux-imx , "netdev@vger.kernel.org" References: <20191127055334.1476-1-qiangqing.zhang@nxp.com> <20191127055334.1476-4-qiangqing.zhang@nxp.com> From: Sean Nyekjaer Message-ID: <9924005b-6136-534d-4a5d-e41716803038@geanix.com> Date: Wed, 27 Nov 2019 10:58:53 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20191127055334.1476-4-qiangqing.zhang@nxp.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US-large Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 27/11/2019 06.56, Joakim Zhang wrote: > Stop mode is entered when Stop mode is requested at chip level and > MCR[LPM_ACK] is asserted by the FlexCAN. > > Double check with IP owner, should poll MCR[LPM_ACK] for stop mode > acknowledgment, not the acknowledgment from chip level which is used > for glitch filter. > > Fixes: 5f186c257fa4(can: flexcan: fix stop mode acknowledgment) > Signed-off-by: Joakim Zhang Tested-by: Sean Nyekjaer > ------ > ChangeLog: > V1->V2: no change. > --- > drivers/net/can/flexcan.c | 64 ++++++++++++++++++++------------------- > 1 file changed, 33 insertions(+), 31 deletions(-) > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c > index 5d5ed28d3005..d178146b3da5 100644 > --- a/drivers/net/can/flexcan.c > +++ b/drivers/net/can/flexcan.c > @@ -388,6 +388,34 @@ static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv > (&priv->regs->mb[bank][priv->mb_size * mb_index]); > } > > +static int flexcan_enter_low_power_ack(struct flexcan_priv *priv) > +{ > + struct flexcan_regs __iomem *regs = priv->regs; > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > + > + while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + udelay(10); > + > + if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + return -ETIMEDOUT; > + > + return 0; > +} > + > +static int flexcan_exit_low_power_ack(struct flexcan_priv *priv) > +{ > + struct flexcan_regs __iomem *regs = priv->regs; > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > + > + while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + udelay(10); > + > + if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > + return -ETIMEDOUT; > + > + return 0; > +} > + > static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) > { > struct flexcan_regs __iomem *regs = priv->regs; > @@ -406,7 +434,6 @@ static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) > static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int ackval; > u32 reg_mcr; > > reg_mcr = priv->read(®s->mcr); > @@ -418,35 +445,24 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) > 1 << priv->stm.req_bit, 1 << priv->stm.req_bit); > > /* get stop acknowledgment */ > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > - ackval, ackval & (1 << priv->stm.ack_bit), > - 0, FLEXCAN_TIMEOUT_US)) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_enter_low_power_ack(priv); > } > > static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int ackval; > u32 reg_mcr; > > /* remove stop request */ > regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, > 1 << priv->stm.req_bit, 0); > > - /* get stop acknowledgment */ > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > - ackval, !(ackval & (1 << priv->stm.ack_bit)), > - 0, FLEXCAN_TIMEOUT_US)) > - return -ETIMEDOUT; > - > reg_mcr = priv->read(®s->mcr); > reg_mcr &= ~FLEXCAN_MCR_SLF_WAK; > priv->write(reg_mcr, ®s->mcr); > > - return 0; > + /* get stop acknowledgment */ > + return flexcan_exit_low_power_ack(priv); > } > > static void flexcan_try_exit_stop_mode(struct flexcan_priv *priv) > @@ -512,39 +528,25 @@ static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv) > static int flexcan_chip_enable(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > u32 reg; > > reg = priv->read(®s->mcr); > reg &= ~FLEXCAN_MCR_MDIS; > priv->write(reg, ®s->mcr); > > - while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - udelay(10); > - > - if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_exit_low_power_ack(priv); > } > > static int flexcan_chip_disable(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > u32 reg; > > reg = priv->read(®s->mcr); > reg |= FLEXCAN_MCR_MDIS; > priv->write(reg, ®s->mcr); > > - while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - udelay(10); > - > - if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_enter_low_power_ack(priv); > } > > static int flexcan_chip_freeze(struct flexcan_priv *priv) >