From patchwork Sat Apr 10 09:11:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?WW9uZyBXdSAo5ZC05YuHKQ==?= X-Patchwork-Id: 419363 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, USER_AGENT_GIT 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 ED4A3C433ED for ; Sat, 10 Apr 2021 09:12:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C100561185 for ; Sat, 10 Apr 2021 09:12:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229992AbhDJJMm (ORCPT ); Sat, 10 Apr 2021 05:12:42 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:37912 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229943AbhDJJMl (ORCPT ); Sat, 10 Apr 2021 05:12:41 -0400 X-UUID: ad36e2de72e04a008e6e87c7d12259dd-20210410 X-UUID: ad36e2de72e04a008e6e87c7d12259dd-20210410 Received: from mtkexhb01.mediatek.inc [(172.21.101.102)] by mailgw02.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1507487187; Sat, 10 Apr 2021 17:12:23 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sat, 10 Apr 2021 17:12:22 +0800 Received: from localhost.localdomain (10.17.3.153) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Sat, 10 Apr 2021 17:12:21 +0800 From: Yong Wu To: Matthias Brugger , Joerg Roedel , Rob Herring , Krzysztof Kozlowski CC: Evan Green , Robin Murphy , Tomasz Figa , Will Deacon , , , , , , , , , Nicolas Boichat , Matthias Kaehlcke , , , , , , Subject: [PATCH v5 03/16] iommu/mediatek: Add device_link between the consumer and the larb devices Date: Sat, 10 Apr 2021 17:11:15 +0800 Message-ID: <20210410091128.31823-4-yong.wu@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20210410091128.31823-1-yong.wu@mediatek.com> References: <20210410091128.31823-1-yong.wu@mediatek.com> MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org MediaTek IOMMU-SMI diagram is like below. all the consumer connect with smi-larb, then connect with smi-common. M4U | smi-common | ------------- | | ... | | larb1 larb2 | | vdec venc When the consumer works, it should enable the smi-larb's power which also need enable the smi-common's power firstly. Thus, First of all, use the device link connect the consumer and the smi-larbs. then add device link between the smi-larb and smi-common. This patch adds device_link between the consumer and the larbs. When device_link_add, I add the flag DL_FLAG_STATELESS to avoid calling pm_runtime_xx to keep the original status of clocks. It can avoid two issues: 1) Display HW show fastlogo abnormally reported in [1]. At the beggining, all the clocks are enabled before entering kernel, but the clocks for display HW(always in larb0) will be gated after clk_enable and clk_disable called from device_link_add(->pm_runtime_resume) and rpm_idle. The clock operation happened before display driver probe. At that time, the display HW will be abnormal. 2) A deadlock issue reported in [2]. Use DL_FLAG_STATELESS to skip pm_runtime_xx to avoid the deadlock. Corresponding, DL_FLAG_AUTOREMOVE_CONSUMER can't be added, then device_link_removed should be added explicitly. [1] https://lore.kernel.org/linux-mediatek/1564213888.22908.4.camel@mhfsdcap03/ [2] https://lore.kernel.org/patchwork/patch/1086569/ Suggested-by: Tomasz Figa Signed-off-by: Yong Wu --- drivers/iommu/mtk_iommu.c | 22 ++++++++++++++++++++++ drivers/iommu/mtk_iommu_v1.c | 20 +++++++++++++++++++- 2 files changed, 41 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 7a7b8260d308..cd054bd3f0df 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -571,22 +571,44 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); struct mtk_iommu_data *data; + struct device_link *link; + struct device *larbdev; + unsigned int larbid; if (!fwspec || fwspec->ops != &mtk_iommu_ops) return ERR_PTR(-ENODEV); /* Not a iommu client device */ data = dev_iommu_priv_get(dev); + /* + * Link the consumer device with the smi-larb device(supplier) + * The device in each a larb is a independent HW. thus only link + * one larb here. + */ + larbid = MTK_M4U_TO_LARB(fwspec->ids[0]); + larbdev = data->larb_imu[larbid].dev; + link = device_link_add(dev, larbdev, + DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS); + if (!link) + dev_err(dev, "Unable to link %s\n", dev_name(larbdev)); return &data->iommu; } static void mtk_iommu_release_device(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + struct mtk_iommu_data *data; + struct device *larbdev; + unsigned int larbid; if (!fwspec || fwspec->ops != &mtk_iommu_ops) return; + data = dev_iommu_priv_get(dev); + larbid = MTK_M4U_TO_LARB(fwspec->ids[0]); + larbdev = data->larb_imu[larbid].dev; + device_link_remove(dev, larbdev); + iommu_fwspec_free(dev); } diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index a82466e4046e..43dbdf692894 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -425,7 +425,9 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) struct of_phandle_args iommu_spec; struct of_phandle_iterator it; struct mtk_iommu_data *data; - int err; + struct device_link *link; + struct device *larbdev; + int err, larbid; of_for_each_phandle(&it, err, dev->of_node, "iommus", "#iommu-cells", -1) { @@ -447,6 +449,14 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) data = dev_iommu_priv_get(dev); + /* Link the consumer device with the smi-larb device(supplier) */ + larbid = mt2701_m4u_to_larb(fwspec->ids[0]); + larbdev = data->larb_imu[larbid].dev; + link = device_link_add(dev, larbdev, + DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS); + if (!link) + dev_err(dev, "Unable to link %s\n", dev_name(larbdev)); + return &data->iommu; } @@ -467,10 +477,18 @@ static void mtk_iommu_probe_finalize(struct device *dev) static void mtk_iommu_release_device(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + struct mtk_iommu_data *data; + struct device *larbdev; + unsigned int larbid; if (!fwspec || fwspec->ops != &mtk_iommu_ops) return; + data = dev_iommu_priv_get(dev); + larbid = mt2701_m4u_to_larb(fwspec->ids[0]); + larbdev = data->larb_imu[larbid].dev; + device_link_remove(dev, larbdev); + iommu_fwspec_free(dev); }