From patchwork Tue Sep 20 10:22:22 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krishna Chaitanya Chundru X-Patchwork-Id: 12981837 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8F54C6FA94 for ; Tue, 20 Sep 2022 10:22:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230011AbiITKW6 (ORCPT ); Tue, 20 Sep 2022 06:22:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229605AbiITKWz (ORCPT ); Tue, 20 Sep 2022 06:22:55 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C5C76DF83; Tue, 20 Sep 2022 03:22:54 -0700 (PDT) Received: from pps.filterd (m0279873.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28K804gS013233; Tue, 20 Sep 2022 10:22:35 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id; s=qcppdkim1; bh=mH6Fwz3K30BlKk2TJCtxVla2r992cpTUFjl1FsBUztU=; b=ZxqwOM7D+fTg/0ff4SiN3dJwpez5HttRrbSvCgx0MGSyrU8EQIbOcuDbXfMB0bxwyL1C O1CfwEmf02/GLn8tO/AFVWIHtdFhclf6xuTfBDRKMjWXpOYSuf2b4X/Jqle2q4IA6xD8 zCwKBB3ffeZu5h68iebg5kfV4ETMG+q03BSS7F6vqQeo2SMCwl8gVZX7yFpnIS39LS9q YFJr9RPdoJand1+yOTJw9vtxbFUwcvhk65gSxy7Hhak4tTQn/Uhx90a2axF7K0lPpw3f 1pGbp2iM9i2PhiRoOwSJpgRtQsMqUI23KyWHBxACeL9Pr2E2FRJYrtyhHmz2UXDseSVT YA== Received: from apblrppmta01.qualcomm.com (blr-bdr-fw-01_GlobalNAT_AllZones-Outside.qualcomm.com [103.229.18.19]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3jpvahjss7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 20 Sep 2022 10:22:34 +0000 Received: from pps.filterd (APBLRPPMTA01.qualcomm.com [127.0.0.1]) by APBLRPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTP id 28KAMUpu016172; Tue, 20 Sep 2022 10:22:30 GMT Received: from pps.reinject (localhost [127.0.0.1]) by APBLRPPMTA01.qualcomm.com (PPS) with ESMTPS id 3jnqrbnbqk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 20 Sep 2022 10:22:30 +0000 Received: from APBLRPPMTA01.qualcomm.com (APBLRPPMTA01.qualcomm.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 28KAMUnB016153; Tue, 20 Sep 2022 10:22:30 GMT Received: from hu-sgudaval-hyd.qualcomm.com (hu-krichai-hyd.qualcomm.com [10.213.110.37]) by APBLRPPMTA01.qualcomm.com (PPS) with ESMTP id 28KAMTkK016147; Tue, 20 Sep 2022 10:22:30 +0000 Received: by hu-sgudaval-hyd.qualcomm.com (Postfix, from userid 4058933) id EAD2B19F4; Tue, 20 Sep 2022 15:52:28 +0530 (+0530) From: Krishna chaitanya chundru To: helgaas@kernel.org Cc: linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, mka@chromium.org, quic_vbadigan@quicinc.com, quic_hemantk@quicinc.com, quic_nitegupt@quicinc.com, quic_skananth@quicinc.com, quic_ramkri@quicinc.com, manivannan.sadhasivam@linaro.org, swboyd@chromium.org, dmitry.baryshkov@linaro.org, svarbanov@mm-sol.com, agross@kernel.org, andersson@kernel.org, konrad.dybcio@somainline.org, lpieralisi@kernel.org, robh@kernel.org, kw@linux.com, bhelgaas@google.com, linux-phy@lists.infradead.org, vkoul@kernel.org, kishon@ti.com, mturquette@baylibre.com, linux-clk@vger.kernel.org, Krishna chaitanya chundru Subject: [PATCH v7 0/5] PCI: qcom: Add system suspend & resume support Date: Tue, 20 Sep 2022 15:52:22 +0530 Message-Id: <1663669347-29308-1-git-send-email-quic_krichai@quicinc.com> X-Mailer: git-send-email 2.7.4 X-QCInternal: smtphost X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: tpr95SO5zlUUUhoZMHUx5re_yGPDoMYK X-Proofpoint-GUID: tpr95SO5zlUUUhoZMHUx5re_yGPDoMYK X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-20_02,2022-09-16_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 lowpriorityscore=0 impostorscore=0 spamscore=0 priorityscore=1501 malwarescore=0 mlxlogscore=953 clxscore=1015 mlxscore=0 adultscore=0 phishscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000 definitions=main-2209200062 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Few PCIe endpoints like NVMe and WLANs are always expecting the device to be in D0 state and the link to be active (or in l1ss) all the time (including in S3 state). This patch series adds this support for allowing the system to enter S3 state (and further low power states) with PCIe Device being in D0 state and with link being in l1ss on qcom platforms. And to get to the lowest power state on Qcom SoC, all the clocks need to be voted off. Since PCIe clocks are managed by qcom platform driver, this logic was added to the qcom platform driver. And when we turn off PCIe PHY-specific clocks, PHY may go off and along with it the link also will go down. To retain, the link state in l1ss with PHY clocks turned off, we need park PCIe PHY in the power-down state so that it can maintain the link state in l1ss with the help of the always-on power domain (aka MX). To support this PHY Power-down state PHY driver has been updated with new interface APIs. Its observed that access to Ep PCIe space to mask MSI/MSIX is happening at the very late stage of suspend path (access by affinity changes while making CPUs offline during suspend, this will happen after devices are suspended (after all phases of suspend ops)). If we turn off clocks in any PM callback, afterwards running into crashes due to un-clocked access due to above mentioned MSI/MSIx access. So, we are making use of syscore framework to turn off the PCIe clocks which will be called after making CPUs offline. During this process, The controller should remain powered on. For this made changes to GDSC. Few endpoints are taking time more time to settle the link in L1ss. So Waiting for max time of 200ms for the link to be stable in L1ss. Krishna chaitanya chundru (5): PCI: qcom: Add system suspend and resume support PCI: qcom: Add retry logic for link to be stable in L1ss phy: core: Add support for phy suspend & resume phy: qcom: Add power suspend & resume callbacks to pcie phy clk: qcom: Enabling PCIe GDSC retention drivers/clk/qcom/gcc-sc7280.c | 2 +- drivers/pci/controller/dwc/pcie-qcom.c | 163 ++++++++++++++++++++++++++++++- drivers/phy/phy-core.c | 30 ++++++ drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 50 ++++++++++ include/linux/phy/phy.h | 20 ++++ 5 files changed, 263 insertions(+), 2 deletions(-)