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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69DC6C43219 for ; Fri, 12 Nov 2021 10:56:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53CF160F39 for ; Fri, 12 Nov 2021 10:56:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234886AbhKLK7V (ORCPT ); Fri, 12 Nov 2021 05:59:21 -0500 Received: from mailgw01.mediatek.com ([60.244.123.138]:57874 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S234853AbhKLK7T (ORCPT ); Fri, 12 Nov 2021 05:59:19 -0500 X-UUID: a52f80a27a7d4a529f46799d7f944407-20211112 X-UUID: a52f80a27a7d4a529f46799d7f944407-20211112 Received: from mtkmbs10n2.mediatek.inc [(172.21.101.183)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 4873376; Fri, 12 Nov 2021 18:56:27 +0800 Received: from mtkcas10.mediatek.inc (172.21.101.39) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.15; Fri, 12 Nov 2021 18:56:25 +0800 Received: from localhost.localdomain (10.17.3.154) by mtkcas10.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 12 Nov 2021 18:56:23 +0800 From: Yong Wu To: Matthias Brugger , Joerg Roedel , Rob Herring , Krzysztof Kozlowski , David Airlie , "Mauro Carvalho Chehab" CC: Evan Green , Robin Murphy , Tomasz Figa , Will Deacon , , , , , , , , , Matthias Kaehlcke , , , , , , Daniel Vetter , Chun-Kuang Hu , Philipp Zabel , Tiffany Lin , "Dafna Hirschfeld" , Hsin-Yi Wang , Eizan Miyamoto , , Frank Wunderlich , , , Subject: [PATCH v9 05/15] iommu/mediatek: Add device_link between the consumer and the larb devices Date: Fri, 12 Nov 2021 18:54:59 +0800 Message-ID: <20211112105509.12010-6-yong.wu@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20211112105509.12010-1-yong.wu@mediatek.com> References: <20211112105509.12010-1-yong.wu@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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. Meanwhile, Currently we don't have a device connect with 2 larbs at the same time. Disallow this case, print the error log. [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 Tested-by: Frank Wunderlich # BPI-R2/MT7623 --- drivers/iommu/mtk_iommu.c | 30 ++++++++++++++++++++++++++++++ drivers/iommu/mtk_iommu_v1.c | 29 ++++++++++++++++++++++++++++- 2 files changed, 58 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 0033c0634e5e..5fed0b64ddd0 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -560,22 +560,52 @@ 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, larbidx, i; 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 that connects with each a larb is a independent HW. + * All the ports in each a device should be in the same larbs. + */ + larbid = MTK_M4U_TO_LARB(fwspec->ids[0]); + for (i = 1; i < fwspec->num_ids; i++) { + larbidx = MTK_M4U_TO_LARB(fwspec->ids[i]); + if (larbid != larbidx) { + dev_err(dev, "Can only use one larb. Fail@larb%d-%d.\n", + larbid, larbidx); + return ERR_PTR(-EINVAL); + } + } + 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 4089077256f4..4052aad75a81 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -423,7 +423,9 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); struct of_phandle_args iommu_spec; struct mtk_iommu_data *data; - int err, idx = 0; + int err, idx = 0, larbid, larbidx; + struct device_link *link; + struct device *larbdev; /* * In the deferred case, free the existed fwspec. @@ -453,6 +455,23 @@ 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]); + for (idx = 1; idx < fwspec->num_ids; idx++) { + larbidx = mt2701_m4u_to_larb(fwspec->ids[idx]); + if (larbid != larbidx) { + dev_err(dev, "Can only use one larb. Fail@larb%d-%d.\n", + larbid, larbidx); + return ERR_PTR(-EINVAL); + } + } + + 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; } @@ -473,10 +492,18 @@ 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); } -- 2.18.0