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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=unavailable 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 C32A1C43381 for ; Thu, 14 Feb 2019 08:41:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 95A482229F for ; Thu, 14 Feb 2019 08:41:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="dXnxVAB+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 95A482229F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Date:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=72sFoNzKp06LANr5Rs2TwTcDtOgKUnIwESS83rU8OFU=; b=dXnxVAB+7J0zSu To02q/quvD+mUjvO5923eR0e4Bw1tpKIKFNlV6KPCoLUYMX8c1wZRY15VDFvHUVHERGQuKL27/aYo mLzTYtGJfXleXg7c2ifEDlmiWVj2yIyzVAgl0UszGcezbcq79Uk8PrtzkywS5b793hzV3khoczDE6 cOwR2nr7Dn6Ctj8s1k0oxuGJTsmtfMP4igSpUkLQZ7QJlvM01mSEBwS9XLOjHNiX6SThOgQW5sGCz 6ThveGbECeawPtjHhq/B+C6UCixjaz97GOCH/fnHm8BvMg800EoDatshIJOBqEgjndCZMZqJbx7cB HgTZBZgHSXFBpbAivWgw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1guCZu-0007O1-5S; Thu, 14 Feb 2019 08:41:06 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1guCZZ-00077e-8R; Thu, 14 Feb 2019 08:40:47 +0000 X-UUID: 8a6226537bb7411495f042d7d2b8a14b-20190214 X-UUID: 8a6226537bb7411495f042d7d2b8a14b-20190214 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 1299376447; Thu, 14 Feb 2019 00:40:33 -0800 Received: from mtkmbs03n1.mediatek.inc (172.21.101.181) by MTKMBS62N2.mediatek.inc (172.29.193.42) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Thu, 14 Feb 2019 00:40:32 -0800 Received: from MTKCAS32.mediatek.inc (172.27.4.184) by mtkmbs03n1.mediatek.inc (172.21.101.181) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Thu, 14 Feb 2019 16:40:29 +0800 Received: from [10.17.3.153] (10.17.3.153) by MTKCAS32.mediatek.inc (172.27.4.170) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Thu, 14 Feb 2019 16:40:28 +0800 Message-ID: <1550133628.16070.32.camel@mhfsdcap03> Subject: Re: [PATCH v1] mmc: mmc: Fix HS setting in mmc_hs400_to_hs200() From: Chaotian Jing To: Ulf Hansson Date: Thu, 14 Feb 2019 16:40:28 +0800 In-Reply-To: References: <1550048812-29068-1-git-send-email-chaotian.jing@mediatek.com> <1550110458.16070.30.camel@mhfsdcap03> X-Mailer: Evolution 3.2.3-0ubuntu6 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190214_004045_467099_2D258EFB X-CRM114-Status: GOOD ( 32.87 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: srv_heupstream , Shawn Lin , "linux-mmc@vger.kernel.org" , Linux Kernel Mailing List , Adrian Hunter , linux-mediatek@lists.infradead.org, Harish Jenny K N , Hongjie Fang , Matthias Brugger , Simon Horman , Kyle Roeschley , Linux ARM Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, 2019-02-14 at 09:14 +0100, Ulf Hansson wrote: > On Thu, 14 Feb 2019 at 03:14, Chaotian Jing wrote: > > > > On Wed, 2019-02-13 at 13:08 +0100, Ulf Hansson wrote: > > > On Wed, 13 Feb 2019 at 10:07, Chaotian Jing wrote: > > > > > > > > mmc_hs400_to_hs200() begins with the card and host in HS400 mode. > > > > Therefore, any commands sent to the card should use HS400 timing. > > > > reduce clock frequency to 50Mhz but without host timming change > > > > may cause CMD6 response CRC error. because host still running at > > > > hs400 mode, and it's hard to find a suitable setting for all eMMC > > > > cards when clock frequency reduced to 50Mhz but card & host still > > > > in hs400 mode. > > > > this patch refers to mmc_select_hs400(), make the reduce clock frequency > > > > after card timing change. > > > > > > > > Signed-off-by: Chaotian Jing > > > > Fixes: ef3d232245ab ("mmc: mmc: Relax checking for switch errors after HS200 switch") > > > > --- > > > > drivers/mmc/core/mmc.c | 29 +++++++++++++++++++++++------ > > > > 1 file changed, 23 insertions(+), 6 deletions(-) > > > > > > > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > > > > index 09c688f..00adc2d 100644 > > > > --- a/drivers/mmc/core/mmc.c > > > > +++ b/drivers/mmc/core/mmc.c > > > > @@ -1239,20 +1239,37 @@ int mmc_hs400_to_hs200(struct mmc_card *card) > > > > int err; > > > > u8 val; > > > > > > > > - /* Reduce frequency to HS */ > > > > - max_dtr = card->ext_csd.hs_max_dtr; > > > > - mmc_set_clock(host, max_dtr); > > > > - > > > > /* Switch HS400 to HS DDR */ > > > > val = EXT_CSD_TIMING_HS; > > > > err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING, > > > > val, card->ext_csd.generic_cmd6_time, 0, > > > > true, false, true); > > > > - if (err) > > > > - goto out_err; > > > > + /* > > > > + * as we are on the way to do re-tune, so if the CMD6 got response CRC > > > > + * error, do not treat it as error. > > > > + */ > > > > + if (err) { > > > > + if (err == -EILSEQ) { > > > > + /* > > > > + * card will busy after sending out response and host > > > > + * driver may not wait busy de-assert when get > > > > + * response CRC error. so just wait enough time to > > > > + * ensure card leave busy state. > > > > + */ > > > > + mmc_delay(card->ext_csd.generic_cmd6_time); > > > > + pr_debug("%s: %s switch to HS got CRC error\n", > > > > + mmc_hostname(host), __func__); > > > > + } else { > > > > + goto out_err; > > > > + } > > > > + } > > > > > > > > mmc_set_timing(host, MMC_TIMING_MMC_DDR52); > > > > > > > > + /* Reduce frequency to HS */ > > > > + max_dtr = card->ext_csd.hs_max_dtr; > > > > + mmc_set_clock(host, max_dtr); > > > > + > > > > > > What Adrian suggested was to not to move this part, but instead, only > > > allow CRC errors from the CMD6 as above. > > > > > > I guess it didn't work for you? > > > > > It should work for me. another issue is CMD6 will be sent 3 times at max > > Alright, let's give it a try then. > > > err = mmc_wait_for_cmd(host, &cmd, MMC_CMD_RETRIES); > > Yeah, that one have I thought about earlier as well. > > > > > if the first CMD6 got response CRC error, then Host driver must wait > > busy signal de-assert before send the next CMD6. > > > > So that it really make sense to issue CMD6(R1B) for 3 times ? if host > > driver did not handle the first CMD6 response CRC error and send second > > CMD6 directly, then this CMD6 will get timeout due to card still in busy > > state. > > I fully agree with you, I don't think it makes sense to retry - not > even for any CMD6, because of the busy signalling the card may raise > afterwards. > > Perhaps we should start with a simple oneliner patch, giving zero > instead of MMC_CMD_RETRIES to mmc_wait_for_cmd() and see how that > plays. > > Then on top we can add the special error handling of the CRC errors, > along the lines of what you suggest. > > Does it make sense? > Sure, I will upload a new patch to change the retry time from 3 to 0 along with this patch. > [...] > > Kind regards > Uffe _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel