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=-14.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 B43B4C433DB for ; Tue, 5 Jan 2021 01:40:27 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 3912322573 for ; Tue, 5 Jan 2021 01:40:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3912322573 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:Subject:To:From: Date:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=gz7h1e6SymDZltUw2qZjuUPtcGoyYCFHA/R9H9Z8zFI=; b=GZQd2lARlpPR5n5BKUVuoPrjq ozEjgc8oBIMkEJsO7qbVS3bbA6MYMYLGQwny3H8UPKcYjqNz1FYJh9ZnYYQ6tE+OPK4Du7ixapdcQ 4B90d9pVfZbEXyvrB/qQXqCvog5dxcZg8zUgSkLKvLUOo7bp3pyoGMPJN89OX8Rk9GtwRTuaci+Ij 7ZqKaXGRNa9YXrbz1B38Or+BNwHHLQvQ6i4zIpwgDjhoK9JU1aAljPxGwxQbnpco4zRgO2p4gayWl AOIH8o4JRVu3QPQFX2AKYgBGow7WWHMbdRf+TYi+LWkoGoesKU3x91AXVmxB7k0r8P6tyiCPMF3Hk ioVOqavTg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kwbKW-0005d5-Op; Tue, 05 Jan 2021 01:40:12 +0000 Received: from m43-15.mailgun.net ([69.72.43.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kwbKU-0005cR-8u for linux-mediatek@lists.infradead.org; Tue, 05 Jan 2021 01:40:11 +0000 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1609810807; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=nwSmoERwazekI4PabcPVm39nxOXqa6nwGKWvYdJ/NMc=; b=PjqUoII+6bEw3uL1Ng3TE5AZ2PoAlT/fCcJbboedw+4MqOek6JvgcAxN7Z6sCRMWr/o7QYrp feGAXmX3HJMJIHNbUOuflcIxqyu97YAmAiP4A5IAFcgj7k/iyxBunvLVKxfweQnhp5MYfWxQ GqqWJo4j1D9e2GdRkILp7vYq8AU= X-Mailgun-Sending-Ip: 69.72.43.15 X-Mailgun-Sid: WyI0ZDIyMyIsICJsaW51eC1tZWRpYXRla0BsaXN0cy5pbmZyYWRlYWQub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n09.prod.us-west-2.postgun.com with SMTP id 5ff3c373f7aeb83bf13576ac (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 05 Jan 2021 01:40:03 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 1F22DC43467; Tue, 5 Jan 2021 01:40:03 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id 8342CC433CA; Tue, 5 Jan 2021 01:39:59 +0000 (UTC) MIME-Version: 1.0 Date: Tue, 05 Jan 2021 09:39:59 +0800 From: Can Guo To: Bjorn Andersson Subject: Re: [PATCH RFC v4 1/1] scsi: ufs: Fix ufs power down/on specs violation In-Reply-To: References: <1608644981-46267-1-git-send-email-ziqichen@codeaurora.org> <4c3035c418d0a0c4344be84fb1919314@codeaurora.org> Message-ID: <6474d14a3055fa645e1004391099ee00@codeaurora.org> X-Sender: cang@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210104_204010_492972_C8A4844E X-CRM114-Status: GOOD ( 42.65 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: nguyenb@codeaurora.org, Alim Akhtar , kwmad.kim@samsung.com, Bean Huo , Satya Tangirala , vinholikatti@gmail.com, jejb@linux.vnet.ibm.com, Bart Van Assche , linux-scsi@vger.kernel.org, Ziqi Chen , Andy Gross , kernel-team@android.com, salyzyn@google.com, "open list:ARM/QUALCOMM SUPPORT" , "James E.J. Bottomley" , Avri Altman , "moderated list:UNIVERSAL FLASH STORAGE HOST CONTROLLER DRIVER..." , Matthias Brugger , stanley.chu@mediatek.com, "moderated list:ARM/Mediatek SoC support" , rnayak@codeaurora.org, saravanak@google.com, martin.petersen@oracle.com, Adrian Hunter , open list , hongwus@codeaurora.org, asutoshd@codeaurora.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On 2021-01-05 02:57, Bjorn Andersson wrote: > On Mon 28 Dec 19:18 CST 2020, Can Guo wrote: > >> On 2020-12-29 01:55, Bjorn Andersson wrote: >> > On Tue 22 Dec 07:49 CST 2020, Ziqi Chen wrote: >> > >> > > As per specs, e.g, JESD220E chapter 7.2, while powering >> > > off/on the ufs device, RST_N signal and REF_CLK signal >> > > should be between VSS(Ground) and VCCQ/VCCQ2. >> > > >> > > To flexibly control device reset line, refactor the function >> > > ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_ >> > > vops_device_reset(sturct ufs_hba *hba, bool asserted). The >> > > new parameter "bool asserted" is used to separate device reset >> > > line pulling down from pulling up. >> > > >> > > Cc: Kiwoong Kim >> > > Cc: Stanley Chu >> > > Signed-off-by: Ziqi Chen >> > > --- >> > > drivers/scsi/ufs/ufs-mediatek.c | 32 ++++++++++++++++---------------- >> > > drivers/scsi/ufs/ufs-qcom.c | 24 +++++++++++++++--------- >> > > drivers/scsi/ufs/ufshcd.c | 36 >> > > +++++++++++++++++++++++++----------- >> > > drivers/scsi/ufs/ufshcd.h | 8 ++++---- >> > > 4 files changed, 60 insertions(+), 40 deletions(-) >> > > >> > > diff --git a/drivers/scsi/ufs/ufs-mediatek.c >> > > b/drivers/scsi/ufs/ufs-mediatek.c >> > > index 80618af..072f4db 100644 >> > > --- a/drivers/scsi/ufs/ufs-mediatek.c >> > > +++ b/drivers/scsi/ufs/ufs-mediatek.c >> > > @@ -841,27 +841,27 @@ static int ufs_mtk_link_startup_notify(struct >> > > ufs_hba *hba, >> > > return ret; >> > > } >> > > >> > > -static int ufs_mtk_device_reset(struct ufs_hba *hba) >> > > +static int ufs_mtk_device_reset(struct ufs_hba *hba, bool asserted) >> > > { >> > > struct arm_smccc_res res; >> > > >> > > - ufs_mtk_device_reset_ctrl(0, res); >> > > + if (asserted) { >> > > + ufs_mtk_device_reset_ctrl(0, res); >> > > >> > > - /* >> > > - * The reset signal is active low. UFS devices shall detect >> > > - * more than or equal to 1us of positive or negative RST_n >> > > - * pulse width. >> > > - * >> > > - * To be on safe side, keep the reset low for at least 10us. >> > > - */ >> > > - usleep_range(10, 15); >> > > - >> > > - ufs_mtk_device_reset_ctrl(1, res); >> > > - >> > > - /* Some devices may need time to respond to rst_n */ >> > > - usleep_range(10000, 15000); >> > > + /* >> > > + * The reset signal is active low. UFS devices shall detect >> > > + * more than or equal to 1us of positive or negative RST_n >> > > + * pulse width. >> > > + * >> > > + * To be on safe side, keep the reset low for at least 10us. >> > > + */ >> > > + usleep_range(10, 15); >> > >> > I see no point in allowing vendors to "tweak" the 1us->10us adjustment. >> > The specification says 1us and we all agree that 10us gives us good >> > enough slack. I.e. this is common code. >> >> Hi Bjron, >> >> We tried, but Samsung fellows wanted 5us. We couldn't get a agreement >> on this delay in short term, so we chose to leave it in vops. >> > > I'm not able to find the code you're referring to. static void exynos_ufs_dev_hw_reset(struct ufs_hba *hba) { struct exynos_ufs *ufs = ufshcd_get_variant(hba); hci_writel(ufs, 0 << 0, HCI_GPIO_OUT); udelay(5); hci_writel(ufs, 1 << 0, HCI_GPIO_OUT); } > >> > >> > > + } else { >> > > + ufs_mtk_device_reset_ctrl(1, res); >> > > >> > > - dev_info(hba->dev, "device reset done\n"); >> > > + /* Some devices may need time to respond to rst_n */ >> > > + usleep_range(10000, 15000); >> > >> > The comment in both the Qualcomm and Mediatek drivers claim that this is >> > sleep relates to the UFS device (not host), so why should it be >> > different? >> > >> > What happens if I take the device that Mediatek see a need for a 10ms >> > delay and hook that up to a Qualcomm host? This really should go in the >> > common code. >> > >> >> Agree, but Qualcomm host didn't have any problems with 10us yet, so if >> we >> put >> the 10ms delay to common code, Qualcomm host would suffer longer delay >> when >> device reset happens - both bootup and resume(xpm_lvl = 5/6) latency >> would >> be increased. >> > > Okay, for the resume case I accept that this is a measurable > difference. > I still believe this is a property of the device and not the platform > though. > True, I also wanted to make the codes simpler and universal for everyone... > Regards, > Bjorn > >> Regards, >> Can Guo. >> >> > >> > >> > As such I really would prefer to see these delays in the common code! >> > You really shouldn't write code based on a speculation that one day >> > there might come someone who need other values - when that day come we >> > can just change the code, and if it never comes we're better off with >> > the cleaner implementation. >> > >> > Regards, >> > Bjorn >> > >> > > + } >> > > >> > > return 0; >> > > } >> > > diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c >> > > index 2206b1e..fed10e5 100644 >> > > --- a/drivers/scsi/ufs/ufs-qcom.c >> > > +++ b/drivers/scsi/ufs/ufs-qcom.c >> > > @@ -1406,10 +1406,11 @@ static void ufs_qcom_dump_dbg_regs(struct >> > > ufs_hba *hba) >> > > /** >> > > * ufs_qcom_device_reset() - toggle the (optional) device reset line >> > > * @hba: per-adapter instance >> > > + * @asserted: assert or deassert device reset line >> > > * >> > > * Toggles the (optional) reset line to reset the attached device. >> > > */ >> > > -static int ufs_qcom_device_reset(struct ufs_hba *hba) >> > > +static int ufs_qcom_device_reset(struct ufs_hba *hba, bool asserted) >> > > { >> > > struct ufs_qcom_host *host = ufshcd_get_variant(hba); >> > > >> > > @@ -1417,15 +1418,20 @@ static int ufs_qcom_device_reset(struct >> > > ufs_hba *hba) >> > > if (!host->device_reset) >> > > return -EOPNOTSUPP; >> > > >> > > - /* >> > > - * The UFS device shall detect reset pulses of 1us, sleep for 10us >> > > to >> > > - * be on the safe side. >> > > - */ >> > > - gpiod_set_value_cansleep(host->device_reset, 1); >> > > - usleep_range(10, 15); >> > > + if (asserted) { >> > > + gpiod_set_value_cansleep(host->device_reset, 1); >> > > >> > > - gpiod_set_value_cansleep(host->device_reset, 0); >> > > - usleep_range(10, 15); >> > > + /* >> > > + * The UFS device shall detect reset pulses of 1us, sleep for >> > > 10us to >> > > + * be on the safe side. >> > > + */ >> > > + usleep_range(10, 15); >> > > + } else { >> > > + gpiod_set_value_cansleep(host->device_reset, 0); >> > > + >> > > + /* Some devices may need time to respond to rst_n */ >> > > + usleep_range(10, 15); >> > > + } >> > > >> > > return 0; >> > > } >> > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c >> > > index e221add..f2daac2 100644 >> > > --- a/drivers/scsi/ufs/ufshcd.c >> > > +++ b/drivers/scsi/ufs/ufshcd.c >> > > @@ -585,7 +585,13 @@ static void ufshcd_device_reset(struct ufs_hba >> > > *hba) >> > > { >> > > int err; >> > > >> > > - err = ufshcd_vops_device_reset(hba); >> > > + err = ufshcd_vops_device_reset(hba, true); >> > > + if (err) { >> > > + dev_err(hba->dev, "asserting device reset failed: %d\n", err); >> > > + return; >> > > + } >> > > + >> > > + err = ufshcd_vops_device_reset(hba, false); >> > > >> > > if (!err) { >> > > ufshcd_set_ufs_dev_active(hba); >> > > @@ -593,7 +599,11 @@ static void ufshcd_device_reset(struct ufs_hba >> > > *hba) >> > > hba->wb_enabled = false; >> > > hba->wb_buf_flush_enabled = false; >> > > } >> > > + dev_dbg(hba->dev, "device reset done\n"); >> > > + } else { >> > > + dev_err(hba->dev, "deasserting device reset failed: %d\n", err); >> > > } >> > > + >> > > if (err != -EOPNOTSUPP) >> > > ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err); >> > > } >> > > @@ -8686,8 +8696,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, >> > > enum ufs_pm_op pm_op) >> > > if (ret) >> > > goto set_dev_active; >> > > >> > > - ufshcd_vreg_set_lpm(hba); >> > > - >> > > disable_clks: >> > > /* >> > > * Call vendor specific suspend callback. As these callbacks may >> > > access >> > > @@ -8703,6 +8711,9 @@ static int ufshcd_suspend(struct ufs_hba *hba, >> > > enum ufs_pm_op pm_op) >> > > */ >> > > ufshcd_disable_irq(hba); >> > > >> > > + if (ufshcd_is_link_off(hba)) >> > > + ufshcd_vops_device_reset(hba, true); >> > > + >> > > ufshcd_setup_clocks(hba, false); >> > > >> > > if (ufshcd_is_clkgating_allowed(hba)) { >> > > @@ -8711,6 +8722,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, >> > > enum ufs_pm_op pm_op) >> > > hba->clk_gating.state); >> > > } >> > > >> > > + ufshcd_vreg_set_lpm(hba); >> > > + >> > > /* Put the host controller in low power mode if possible */ >> > > ufshcd_hba_vreg_set_lpm(hba); >> > > goto out; >> > > @@ -8778,18 +8791,19 @@ static int ufshcd_resume(struct ufs_hba >> > > *hba, enum ufs_pm_op pm_op) >> > > old_link_state = hba->uic_link_state; >> > > >> > > ufshcd_hba_vreg_set_hpm(hba); >> > > + >> > > + ret = ufshcd_vreg_set_hpm(hba); >> > > + if (ret) >> > > + goto out; >> > > + >> > > /* Make sure clocks are enabled before accessing controller */ >> > > ret = ufshcd_setup_clocks(hba, true); >> > > if (ret) >> > > - goto out; >> > > + goto disable_vreg; >> > > >> > > /* enable the host irq as host controller would be active soon */ >> > > ufshcd_enable_irq(hba); >> > > >> > > - ret = ufshcd_vreg_set_hpm(hba); >> > > - if (ret) >> > > - goto disable_irq_and_vops_clks; >> > > - >> > > /* >> > > * Call vendor specific resume callback. As these callbacks may >> > > access >> > > * vendor specific host controller register space call them when the >> > > @@ -8797,7 +8811,7 @@ static int ufshcd_resume(struct ufs_hba *hba, >> > > enum ufs_pm_op pm_op) >> > > */ >> > > ret = ufshcd_vops_resume(hba, pm_op); >> > > if (ret) >> > > - goto disable_vreg; >> > > + goto disable_irq_and_vops_clks; >> > > >> > > /* For DeepSleep, the only supported option is to have the link >> > > off */ >> > > WARN_ON(ufshcd_is_ufs_dev_deepsleep(hba) && >> > > !ufshcd_is_link_off(hba)); >> > > @@ -8864,8 +8878,6 @@ static int ufshcd_resume(struct ufs_hba *hba, >> > > enum ufs_pm_op pm_op) >> > > ufshcd_link_state_transition(hba, old_link_state, 0); >> > > vendor_suspend: >> > > ufshcd_vops_suspend(hba, pm_op); >> > > -disable_vreg: >> > > - ufshcd_vreg_set_lpm(hba); >> > > disable_irq_and_vops_clks: >> > > ufshcd_disable_irq(hba); >> > > if (hba->clk_scaling.is_allowed) >> > > @@ -8876,6 +8888,8 @@ static int ufshcd_resume(struct ufs_hba *hba, >> > > enum ufs_pm_op pm_op) >> > > trace_ufshcd_clk_gating(dev_name(hba->dev), >> > > hba->clk_gating.state); >> > > } >> > > +disable_vreg: >> > > + ufshcd_vreg_set_lpm(hba); >> > > out: >> > > hba->pm_op_in_progress = 0; >> > > if (ret) >> > > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h >> > > index 9bb5f0e..d5fbaba 100644 >> > > --- a/drivers/scsi/ufs/ufshcd.h >> > > +++ b/drivers/scsi/ufs/ufshcd.h >> > > @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info { >> > > * @resume: called during host controller PM callback >> > > * @dbg_register_dump: used to dump controller debug information >> > > * @phy_initialization: used to initialize phys >> > > - * @device_reset: called to issue a reset pulse on the UFS device >> > > + * @device_reset: called to assert or deassert device reset line >> > > * @program_key: program or evict an inline encryption key >> > > * @event_notify: called to notify important events >> > > */ >> > > @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops { >> > > int (*resume)(struct ufs_hba *, enum ufs_pm_op); >> > > void (*dbg_register_dump)(struct ufs_hba *hba); >> > > int (*phy_initialization)(struct ufs_hba *); >> > > - int (*device_reset)(struct ufs_hba *hba); >> > > + int (*device_reset)(struct ufs_hba *hba, bool asserted); >> > > void (*config_scaling_param)(struct ufs_hba *hba, >> > > struct devfreq_dev_profile *profile, >> > > void *data); >> > > @@ -1216,10 +1216,10 @@ static inline void >> > > ufshcd_vops_dbg_register_dump(struct ufs_hba *hba) >> > > hba->vops->dbg_register_dump(hba); >> > > } >> > > >> > > -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba) >> > > +static inline int ufshcd_vops_device_reset(struct ufs_hba *hba, >> > > bool asserted) >> > > { >> > > if (hba->vops && hba->vops->device_reset) >> > > - return hba->vops->device_reset(hba); >> > > + return hba->vops->device_reset(hba, asserted); >> > > >> > > return -EOPNOTSUPP; >> > > } >> > > -- >> > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora >> > > Forum, >> > > a Linux Foundation Collaborative Project >> > > _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek