From patchwork Thu Mar 21 17:17:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Green X-Patchwork-Id: 10864111 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 E26231823 for ; Thu, 21 Mar 2019 17:18:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C5EA02A307 for ; Thu, 21 Mar 2019 17:18:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B956D2A3C3; Thu, 21 Mar 2019 17:18:11 +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=unavailable 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 34FB12A384 for ; Thu, 21 Mar 2019 17:18:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728316AbfCURSK (ORCPT ); Thu, 21 Mar 2019 13:18:10 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:36427 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728138AbfCURSK (ORCPT ); Thu, 21 Mar 2019 13:18:10 -0400 Received: by mail-pf1-f195.google.com with SMTP id p10so4729164pff.3 for ; Thu, 21 Mar 2019 10:18:09 -0700 (PDT) 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=VMT+x4mc9nWPEtzF6nquPrOfYT6Bd4oIFLZumkp/DWo=; b=k/tvOOjX9JvHeH+GH8hJ6hp/npWpf9z2XZSpJQRJNxXsMiWNz8Sp+pifmj0+ItPvfb M9Lqqf0ByjjJKGMq7kxiyay9olNCOCN/FPx0tpZC2lmeU0Ynequ0M0WT4pQyZHuHbPAo vVwHd91hbuZG6yKwUGLCSWnOV7SnBDGI3RJwI= 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=VMT+x4mc9nWPEtzF6nquPrOfYT6Bd4oIFLZumkp/DWo=; b=GvmW+cVJf4m+x4p94tZBsJxYFN/8OKhII08muDwcIhqyj2lVHanHfJbdyg/QbgmscP EniKH7nDtgwU0hPk05cwyDTOLwqCfjI9ajQBXblySDSJ4fArXKm7XkoRjrEp2eENfi7W qrmg40aqXXCiAsyzEgyF+pj7yxGIkYMFLxLQhRe/sqmCJax0+zGU9JJ37Hxw09l3td+P rn0Sni/wteL3BMAMLg+/WOponXll4uRmgTwl9joMqaISllScdz6ETgjZsQ2XkCTYZE8u t82T1rfFFUKUBg4b/MIK8pNt5/4x1r3TUZSMd7Y7RAAS6eYgHFsl8Ekqzb6ciTLfsUM9 Ch8w== X-Gm-Message-State: APjAAAWPZC13s3XABoAJDk0c4AYJpLBXBvnT/CDk9hQaCtubsBbKXoJ8 rKkvgBgxD7kQQR3Q7ma6JztVeg== X-Google-Smtp-Source: APXvYqwI92qJSvbV93CT0Lit8mT4y4HFWEN8jpe20WbW5NwA0Em6Eh4mlqKuTJfvWgS/N6n5uyqJUQ== X-Received: by 2002:a63:2a8f:: with SMTP id q137mr4321742pgq.31.1553188689203; Thu, 21 Mar 2019 10:18:09 -0700 (PDT) Received: from evgreen2.mtv.corp.google.com ([2620:15c:202:201:ffda:7716:9afc:1301]) by smtp.gmail.com with ESMTPSA id z6sm20953866pgo.31.2019.03.21.10.18.07 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 21 Mar 2019 10:18:08 -0700 (PDT) From: Evan Green To: Kishon Vijay Abraham I Cc: Stephen Boyd , Marc Gonzalez , Can Guo , Vivek Gautam , Douglas Anderson , Asutosh Das , Evan Green , devicetree@vger.kernel.org, Pedro Sousa , liwei , linux-scsi@vger.kernel.org, linux-arm-msm@vger.kernel.org, Bart Van Assche , linux-kernel@vger.kernel.org, Andy Gross , Subhash Jadavani , "Martin K. Petersen" , Alim Akhtar , Rob Herring , Avri Altman , Mark Rutland , "James E.J. Bottomley" , Janek Kotas , David Brown Subject: [PATCH v5 0/8] phy: qcom-ufs: Enable regulators to be off in suspend Date: Thu, 21 Mar 2019 10:17:52 -0700 Message-Id: <20190321171800.104681-1-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. Changes in v5: - Updated tags 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(-)