From patchwork Fri Nov 15 06:09:30 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11245245 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 42D11159A for ; Fri, 15 Nov 2019 06:10:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22A8D2072B for ; Fri, 15 Nov 2019 06:10:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="nwHmypOg"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="J1JI14Mn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727281AbfKOGKe (ORCPT ); Fri, 15 Nov 2019 01:10:34 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:38798 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725848AbfKOGKe (ORCPT ); Fri, 15 Nov 2019 01:10:34 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 6AA6261138; Fri, 15 Nov 2019 06:10:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1573798232; bh=WNEWdwZREdio4xxgu3pDdGhRebknE1NKUlrUVDdMD4E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nwHmypOgNRgWjVUIdWc3GFO0kfo3bsUDai94T4CSVX/OkEiarY9iUSV+/kpNlbO+r 6HoXgpUaWwipxGt7T08wnzRnCf1wchj+ndkYhciGV8dVKHk485atEirY2T93EZN6Dc ZpZvVlyCW0MAbvKO13xDMvATAFTo5E5WI9iNkyiE= X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=2.0 tests=ALL_TRUSTED,BAYES_00, DKIM_INVALID,DKIM_SIGNED,SPF_NONE autolearn=no autolearn_force=no version=3.4.0 Received: from pacamara-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: cang@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 52CF661250; Fri, 15 Nov 2019 06:10:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1573798226; bh=WNEWdwZREdio4xxgu3pDdGhRebknE1NKUlrUVDdMD4E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J1JI14MnWWvNHhPDVH2ubVseAwGTW/0RAKwyIrmnVJwPGP73Z76Sli7yO6WUPbUng glTj5MOr2hZTNssSxh2WnHfvTSAOy14xVOk0eUjMkTJAudA2ite/js7K8f1A9puZC3 wPB9AF/OkWhwgTiQ4f5wueOi5w/S0AjRqMPU3lEU= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 52CF661250 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=cang@codeaurora.org From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: Subhash Jadavani , Alim Akhtar , Avri Altman , Pedro Sousa , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Tomas Winkler , Venkat Gopalakrishnan , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v5 7/7] scsi: ufs: Fix error handing during hibern8 enter Date: Thu, 14 Nov 2019 22:09:30 -0800 Message-Id: <1573798172-20534-8-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1573798172-20534-1-git-send-email-cang@codeaurora.org> References: <1573798172-20534-1-git-send-email-cang@codeaurora.org> MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Subhash Jadavani During clock gating (ufshcd_gate_work()), we first put the link hibern8 by calling ufshcd_uic_hibern8_enter() and if ufshcd_uic_hibern8_enter() returns success (0) then we gate all the clocks. Now let’s zoom in to what ufshcd_uic_hibern8_enter() does internally: It calls __ufshcd_uic_hibern8_enter() and if failure is encountered, link recovery shall put the link back to the highest HS gear and returns success (0) to ufshcd_uic_hibern8_enter() which is the issue as link is still in active state due to recovery! Now ufshcd_uic_hibern8_enter() returns success to ufshcd_gate_work() and hence it goes ahead with gating the UFS clock while link is still in active state hence I believe controller would raise UIC error interrupts. But when we service the interrupt, clocks might have already been disabled! This change fixes for this by returning failure from __ufshcd_uic_hibern8_enter() if recovery succeeds as link is still not in hibern8, upon receiving the error ufshcd_hibern8_enter() would initiate retry to put the link state back into hibern8. Signed-off-by: Subhash Jadavani Signed-off-by: Can Guo Reviewed-by: Avri Altman Reviewed-by: Bean Huo --- drivers/scsi/ufs/ufshcd.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index d662641..e1ee961 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3891,15 +3891,24 @@ static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba) ktime_to_us(ktime_sub(ktime_get(), start)), ret); if (ret) { + int err; + dev_err(hba->dev, "%s: hibern8 enter failed. ret = %d\n", __func__, ret); /* - * If link recovery fails then return error so that caller - * don't retry the hibern8 enter again. + * If link recovery fails then return error code returned from + * ufshcd_link_recovery(). + * If link recovery succeeds then return -EAGAIN to attempt + * hibern8 enter retry again. */ - if (ufshcd_link_recovery(hba)) - ret = -ENOLINK; + err = ufshcd_link_recovery(hba); + if (err) { + dev_err(hba->dev, "%s: link recovery failed", __func__); + ret = err; + } else { + ret = -EAGAIN; + } } else ufshcd_vops_hibern8_notify(hba, UIC_CMD_DME_HIBER_ENTER, POST_CHANGE); @@ -3913,7 +3922,7 @@ static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) for (retries = UIC_HIBERN8_ENTER_RETRIES; retries > 0; retries--) { ret = __ufshcd_uic_hibern8_enter(hba); - if (!ret || ret == -ENOLINK) + if (!ret) goto out; } out: