From patchwork Wed Feb 13 23:25:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Green X-Patchwork-Id: 10811313 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 34F281575 for ; Wed, 13 Feb 2019 23:27:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 24E3C2DCF4 for ; Wed, 13 Feb 2019 23:27:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1923A2DE09; Wed, 13 Feb 2019 23:27:08 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 791002DCF4 for ; Wed, 13 Feb 2019 23:27:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389406AbfBMX0O (ORCPT ); Wed, 13 Feb 2019 18:26:14 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:44459 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389316AbfBMX0O (ORCPT ); Wed, 13 Feb 2019 18:26:14 -0500 Received: by mail-pf1-f195.google.com with SMTP id u6so1939848pfh.11 for ; Wed, 13 Feb 2019 15:26:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pElnodFdKG+v6XH9vX+eTEemSmnJPk/UTDU6j7fos9g=; b=kOwCW/aemgmD/ezHrbKIb/LlrSYO9kXLlGwCM5+3ql/JmBxcMhgveh5C4fa5QQEsEV Qbt/ALkbQzJXfvTL2SuC9JGlP7N9x4gTcz56cmux17VktubV3Ub/XQP7a8swv/fOoE4R ME4ChKKcY0CjeCES1xwj2HwEAuElyuNXzkhLg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pElnodFdKG+v6XH9vX+eTEemSmnJPk/UTDU6j7fos9g=; b=aV7YMfBUZFT1WKNZsDKxHD0skRBfML/19gpeyCPPIJJKSAmaMSC2ahJOcutUWWMdth FL46CdjUCV4ejoQCiu1zAyPiy9LdP45wtgAom/lOgRfWJPV3G97bw2vbq52shXj88F0h KlngOhpKzRJm8kw+/TgFzMsg1tCnodCZeoBVU81Ycfbdf5uyjalo3yx9LQnDIKoWii6p XieH3tOnG7arfMOe1OW47WzMhMIj0sj/KTQnB8Wdu9nw59YYOO8jSQ+XlugV+CT97xSe lWtPMWwBlmUhdUpFAZwf4JYzSlsecwY+dPpxBNdNsr1sb9+85lxQA6p+pQ9RTqCuoM45 WeWQ== X-Gm-Message-State: AHQUAubvM1JKL0Pszlnc3Gzje+L5x2LsvASTHAFh4cmdYSzmW7Eq0/jr gCVd3nLt6RXB/gBQkL0GcYf7/g== X-Google-Smtp-Source: AHgI3IYbQHQOdjUzn3fTwUmmeh6cwPPL48mZszwibbtlTI7T8tgNKIar2B1DK13Al6blezIX0QNhLQ== X-Received: by 2002:aa7:8c8c:: with SMTP id p12mr802429pfd.0.1550100373120; Wed, 13 Feb 2019 15:26:13 -0800 (PST) Received: from evgreen2.mtv.corp.google.com ([2620:15c:202:201:ffda:7716:9afc:1301]) by smtp.gmail.com with ESMTPSA id d129sm560660pfc.31.2019.02.13.15.26.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 13 Feb 2019 15:26:12 -0800 (PST) From: Evan Green To: Andy Gross , Kishon Vijay Abraham I Cc: Stephen Boyd , Marc Gonzalez , Can Guo , Vivek Gautam , Douglas Anderson , Asutosh Das , Evan Green , Bjorn Andersson , Arnd Bergmann , Grygorii Strashko , Rob Herring , Vinayak Holikatti , Jeffrey Hugo , linux-scsi@vger.kernel.org, David Brown , "James E.J. Bottomley" , devicetree@vger.kernel.org, liwei , linux-arm-msm@vger.kernel.org, "Martin K. Petersen" , linux-kernel@vger.kernel.org, Manu Gautam , Mark Rutland , Subhash Jadavani Subject: [PATCH v4 0/8] phy: qcom-ufs: Enable regulators to be off in suspend Date: Wed, 13 Feb 2019 15:25:18 -0800 Message-Id: <20190213232526.26995-1-evgreen@chromium.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The goal with this series is to enable shutting off regulators that power UFS during system suspend. In "the good life" version of this, we'd just disable the regulators in phy_poweroff() and be done with it. Unfortunately, that's not symmetric, as regulators are not enabled during phy_poweron(). Ok, so you might think we could just move the regulator enable and anything else that needs to come along into phy_poweron(), so that we can then undo it all in phy_poweroff(). That's where things get tricky. The qcom-qmp-phy overloaded the phy_init() and phy_poweron() callbacks, basically to mean "init phase 1" and "init phase 2". There are two phases because they have this phy_reset bit outside of the phy (in the UFS controller registers), and they need to make sure this bit is toggled at specific points in the phy init sequence. So there's this implicit sequence in the init dance between ufs-qcom.c and phy-qcom-qmp.c: 1) ufs-qcom asserts the PHY reset bit. 2) phy-qcom-qmp phy_init() does most of its initialization, but exits early. 3) ufs-qcom deasserts the PHY reset bit. 4) phy-qcom-qmp phy_poweron() finishes its initialization. This init dance is very difficult to follow in the code (since it's split between two drivers and not spelled out well), and arguably represents a deficiency in the hardware description of these devices. In this series I'm proposing tweaking the bindings for the Qualcomm UFS controller and PHY. In it we expose a reset controller from the UFS controller, that is then picked up and used from the PHY code. With this, the phy code can be reorganized to complete its initialization in a single function, removing the implicit two-phase overloading. Then I can move most of the phy initialization, including enabling the regulators, into phy_poweron(). Now, when phy_poweroff() is called, the phy actually powers off. This finally disables the regulators and allows me to save power in system suspend. Because the UFS PHY reset bit is now toggled in the PHY, rather than in ufs-qcom, this also percolated to all other PHYs using ufs-qcom, which from what I can see is just 8996. I removed the calls to phy_poweroff() during clock gating. This was originally dialing down a clock or two, while leaving the phy powered. I've now changed the semantics of phy_poweroff() to, well, actually power off. This works great for userlands that have set UFS's spm_lvl to 5 (off) like I have, but maybe changes power consumption for devices that have spm_lvl set to 3. I could try to use phy_init() and phy_poweron() as the two different possible transitions (fully off, and clocks off respectively), but I'm not sure if it actually matters, and I like the idea that phy_poweroff() really does power the thing off. Also, I don't have an 8996 device to test. If someone is able to test this out and perhaps point out any (hopefully obvious) bugs in the 8996 portion, I'd be grateful. This patch is based atop phy-next, plus the UFS DT nodes, which are now patch 3, 4, 5 of [1]. [1] https://lore.kernel.org/lkml/20181210192826.241350-1-evgreen@chromium.org/ Changes in v4: - Do reset_control_* unconditionally since null is handled (Stephen). - Keep doing reset_control* unconditionally through refactor (Stephen). Changes in v3: - Refactor to only expose the reset controller in one change (Stephen). - Add period to comment (Stephen). - Reset err to 0 in ignored error case (Stephen). - Add include of reset-controller.h (Stephen) - Refactored to move reset control in a single commit (Stephen) - Use no_pcs_sw_reset as an indicator of UFS reset in qmp-phy (Stephen). - Assign ret = PTR_ERR() earlier, for better reuse (Stephen). - Refactor init => poweron for all PHYs and UFS in one step (Stephen) Changes in v2: - Added resets to example (Stephen). - Remove include of reset.h (Stephen) - Fix error print of phy_power_on (Stephen) - Comment for reset controller warnings on id != 0 (Stephen) - Add static to ufs_qcom_reset_ops (Stephen). - Use devm_* to get the reset (Stephen) - Clear ufs_reset on error getting it - Remove needless error print (Stephen) - Use devm_ to get the reset (Stephen) - Removed whitespace changes (Stephen) Evan Green (8): dt-bindings: ufs: Add #reset-cells for Qualcomm controllers dt-bindings: phy-qcom-qmp: Add UFS PHY reset dt-bindings: phy: qcom-ufs: Add resets property arm64: dts: sdm845: Add UFS PHY reset arm64: dts: msm8996: Add UFS PHY reset controller scsi: ufs: qcom: Expose the reset controller for PHY phy: qcom: Utilize UFS reset controller phy: ufs-qcom: Refactor all init steps into phy_poweron .../devicetree/bindings/phy/qcom-qmp-phy.txt | 6 +- .../devicetree/bindings/ufs/ufs-qcom.txt | 5 +- .../devicetree/bindings/ufs/ufshcd-pltfrm.txt | 3 + arch/arm64/boot/dts/qcom/msm8996.dtsi | 4 +- arch/arm64/boot/dts/qcom/sdm845.dtsi | 3 + drivers/phy/qualcomm/phy-qcom-qmp.c | 112 +++++++++-------- drivers/phy/qualcomm/phy-qcom-ufs-i.h | 5 +- drivers/phy/qualcomm/phy-qcom-ufs-qmp-14nm.c | 25 +--- drivers/phy/qualcomm/phy-qcom-ufs-qmp-20nm.c | 25 +--- drivers/phy/qualcomm/phy-qcom-ufs.c | 57 ++++++--- drivers/scsi/ufs/Kconfig | 1 + drivers/scsi/ufs/ufs-qcom.c | 114 +++++++++++------- drivers/scsi/ufs/ufs-qcom.h | 4 + 13 files changed, 193 insertions(+), 171 deletions(-)