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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?zixMIiWI2Xv6/eDvG0OnShUW302dKZ1oztPreLu/e+vy9N4ww9tSa584IytK?= =?us-ascii?Q?PB/qfDMUjmuE8TTEu4nj4W642XUxfzchZa3gf3PG8s56ik4faOdFP69khdG9?= =?us-ascii?Q?B0TbchOqf5K6zCmoo7+T4Y+iBaTIu4zw7YnrmhYvlLBVmaub2MUnarjX2/x4?= =?us-ascii?Q?P42K58O2ZlU/VUe3UI7fMSalFg9agJ1jR82Jpx9oaB3RbvmW4Gjw2wnuEUrH?= =?us-ascii?Q?SgH35i0jfd/3PYkNhE4jVI3xx/86qqbY96GWenKFrHbEhNpPT5QjZcPwLV7s?= =?us-ascii?Q?mYh4HBusNBmSwDr3k3Uakdaz0HBk3LBICeT4Nna1PgmqHXmkOnwYab6Xs97u?= =?us-ascii?Q?YV54faFiBniqL9U0+1mw813IroOS350SuO2xGVm8KKqkt4qts4fmMhZQILdl?= =?us-ascii?Q?D9czkb9pnaEKtHC/Yne5MxPkvBpKDS43fXaHrjU//BKRF1A2/KMA5BUVjrHd?= =?us-ascii?Q?EhP3Nf82Xl4w/DAudwpVzn4XuPtZA4d8tPLnWS5yXkXGt5VTta+fjj4u2j2D?= =?us-ascii?Q?Pjjdb2dZYorK2OPTY7gMLe/3qpjNI04bREHiLQEedzGadKtZDNEoFQTZ7onm?= =?us-ascii?Q?1yrKJI/lNVbFLuX42SFoWJN/+u+Gni9Bje+BUuFh2D38xLyJs3wZid6m4A4X?= =?us-ascii?Q?NyGEzb9JdjggMPU0WQkFuDk3tUrhfRksBOVSzfCd59aq9nesVncKxeL/fP5W?= =?us-ascii?Q?L4HsRO6NS/dwFMq8YF1WpWybj65jntFseIXvHWK8qshnnzW9ZvjJ/CT3nFIf?= =?us-ascii?Q?EiXlqdrd6M5vbr1s3LqSsNfzWL+t8Mmnq9roziu3+SGtTZxL3HzuulThMxo5?= =?us-ascii?Q?TNEQh9Lntww16RBqo1FeGUJmBmD85YIAx6tr0HMY3WBmv0WJQ5ut+HeCYV0P?= =?us-ascii?Q?7Wg42E6hfeFn/cHz/EeUEHrXWQ05+Qu6phIoYAep0Wf8qt0ok8E0IHStjqPV?= =?us-ascii?Q?5+SY4O14kl8pQc7LL9Y08eo9NybFPlbuFgaiYZm4XtVk8KUAfLk9ZEnz5dHu?= =?us-ascii?Q?Ov5oCN3/uUSH41BSB0IQb3kjdu/wKB0KTRoHRPRTHOtSBogyRcfTYych6ckv?= =?us-ascii?Q?m8KgY1fwsK4qB3CA46IwM2lGWhqbL36gGfZq2qIGOcy1Zf4JcyTuBj6FD+jK?= =?us-ascii?Q?KHWo/+fYjVV+4IxVkDi2gKjC1sbkXZUPBjLD8pJ6u6QzEuaimDUz+SHbXmLA?= =?us-ascii?Q?wytdJCnN1XLYTbpoUnk//nRgGevPA0ne9anP5adUmYT1HEc8G7wjlfs5t2gX?= =?us-ascii?Q?oAnk9XCa9OsYpWy1gDeom+dp+LbxV1wQ5Mu7ZUwq7KtYsRIAAub00TbzHhT+?= =?us-ascii?Q?ID3zbr8H6WYjJn3R7/1THzhJWnU89xCQXpCBlKWwXyDPckyDg1I4L018SAwP?= =?us-ascii?Q?SBuaXDGpbhF6MIb4donBzyqhjum7Qo0mA+pUqlOCZe2JN0upavqGGjpVug+P?= =?us-ascii?Q?11bYAHWt1r8ojjzCX+eFIGSVmS2kEDKm1jqUHQAhAjH/o1WMuhk9IgRV3MpP?= =?us-ascii?Q?2gT7X64Pgc+MSPaPj3+zfI3wCBWY4BQU/Wl9UQwO3utPrU4LbtjfXyAOOR+W?= =?us-ascii?Q?Fj/bJ2Uy1ccuHxC61QXoDxGXqp5T+xllN4wPcONP?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8b15352d-b0b1-46e9-1f99-08dbb86a69c1 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Sep 2023 17:12:18.4928 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: IXF87hTdksitFIhWKNp7eIAm676d65vqx48cC2ZgsLHqEvVbH8NiVg385khk1PYC X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB7651 On Fri, Sep 15, 2023 at 05:58:06PM +0100, Robin Murphy wrote: > Much as I'd like to remove iommu_present(), the final remaining users > are proving stubbornly difficult to clean up, so kick that can down > the road and just rework it to preserve the current behaviour without > depending on bus ops. > > Reviewed-by: Lu Baolu > Reviewed-by: Jason Gunthorpe > Signed-off-by: Robin Murphy > > --- > > v3: Tweak to use the ops-based check rather than group-based, to > properly match the existing behaviour > --- > drivers/iommu/iommu.c | 17 ++++++++++++++++- > 1 file changed, 16 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 4566d0001cd3..2f29ee9dea64 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -1907,9 +1907,24 @@ int bus_iommu_probe(const struct bus_type *bus) > return 0; > } > > +static int __iommu_present(struct device *dev, void *unused) > +{ > + return dev_has_iommu(dev); > +} This is not locked right.. Rather than perpetuate that, can we fix the two callers instead? Maybe this for mtk: diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index 93552d76b6e778..e7fe0e6f27de85 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -500,6 +500,8 @@ static int mtk_drm_kms_init(struct drm_device *drm) dev_err(drm->dev, "Need at least one OVL device\n"); goto err_component_unbind; } + if (!device_iommu_mapped(dma_dev)) + return -EPROBE_DEFER; for (i = 0; i < private->data->mmsys_dev_num; i++) private->all_drm_private[i]->dma_dev = dma_dev; @@ -583,9 +585,6 @@ static int mtk_drm_bind(struct device *dev) struct drm_device *drm; int ret, i; - if (!iommu_present(&platform_bus_type)) - return -EPROBE_DEFER; - pdev = of_find_device_by_node(private->mutex_node); if (!pdev) { dev_err(dev, "Waiting for disp-mutex device %pOF\n", ? It doesn't seem to use the iommu API so I guess all it is doing is trying to fix some kind of probe ordering issue? Maybe the probe ordering issue is already gone and we can just delete the check? And tegra: if (host1x_drm_wants_iommu(dev) && iommu_present(&platform_bus_type)) { tegra->domain = iommu_domain_alloc(&platform_bus_type); if (!tegra->domain) { Lets do the same: if (host1x_drm_wants_iommu(dev) && device_iommu_mapped(dev->dev.parent)) { ? Alternatively how about: bool iommu_present(void) { bool ret; spin_lock(&iommu_device_lock); ret = !list_empty(&iommu_device_list); spin_unlock(&iommu_device_lock); return ret; } EXPORT_SYMBOL_GPL(iommu_present); Since neither of the two users is really needing anything more than that? Jason From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 223C9C46CA1 for ; Mon, 18 Sep 2023 17:12:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:In-Reply-To:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=REDwBDEMfGOCngSSeDrNJHDsSInmTDMG59BeARDPc9o=; b=blmmu8kTJ8OqyT eGhmR9V4OXOBEEcs88l18vlOFd51t3kF0DKJEb//KxVR8Yx23kvEWDxK54tKAvhBSN+kJhPdI8rL2 xvMvv27tzoVLBKoyINqQ12btkTuU+nvqC0bfX/3CfFaSICccXiVEP7IrKoJ1SvODTVl80T98/CT65 sX6KdhmyXBN4kZGdqFYzsV7Z1EsNOu7Z8G8V8UhcCiYWFZ7d6ZBmJV3kXFuQVF/Spq1WoeioI9QbA +YOs3XAIiUfcA4uL5lOtEzeYR6z8JMG839Wgw4GBOmge1eab8gPRbLOhESm4QoA7oNtwcJPokBTK/ j4mHErd5LDcLxlw9Uu+g==; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Sep 15, 2023 at 05:58:06PM +0100, Robin Murphy wrote: > Much as I'd like to remove iommu_present(), the final remaining users > are proving stubbornly difficult to clean up, so kick that can down > the road and just rework it to preserve the current behaviour without > depending on bus ops. > > Reviewed-by: Lu Baolu > Reviewed-by: Jason Gunthorpe > Signed-off-by: Robin Murphy > > --- > > v3: Tweak to use the ops-based check rather than group-based, to > properly match the existing behaviour > --- > drivers/iommu/iommu.c | 17 ++++++++++++++++- > 1 file changed, 16 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 4566d0001cd3..2f29ee9dea64 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -1907,9 +1907,24 @@ int bus_iommu_probe(const struct bus_type *bus) > return 0; > } > > +static int __iommu_present(struct device *dev, void *unused) > +{ > + return dev_has_iommu(dev); > +} This is not locked right.. Rather than perpetuate that, can we fix the two callers instead? Maybe this for mtk: diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index 93552d76b6e778..e7fe0e6f27de85 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -500,6 +500,8 @@ static int mtk_drm_kms_init(struct drm_device *drm) dev_err(drm->dev, "Need at least one OVL device\n"); goto err_component_unbind; } + if (!device_iommu_mapped(dma_dev)) + return -EPROBE_DEFER; for (i = 0; i < private->data->mmsys_dev_num; i++) private->all_drm_private[i]->dma_dev = dma_dev; @@ -583,9 +585,6 @@ static int mtk_drm_bind(struct device *dev) struct drm_device *drm; int ret, i; - if (!iommu_present(&platform_bus_type)) - return -EPROBE_DEFER; - pdev = of_find_device_by_node(private->mutex_node); if (!pdev) { dev_err(dev, "Waiting for disp-mutex device %pOF\n", ? It doesn't seem to use the iommu API so I guess all it is doing is trying to fix some kind of probe ordering issue? Maybe the probe ordering issue is already gone and we can just delete the check? And tegra: if (host1x_drm_wants_iommu(dev) && iommu_present(&platform_bus_type)) { tegra->domain = iommu_domain_alloc(&platform_bus_type); if (!tegra->domain) { Lets do the same: if (host1x_drm_wants_iommu(dev) && device_iommu_mapped(dev->dev.parent)) { ? Alternatively how about: bool iommu_present(void) { bool ret; spin_lock(&iommu_device_lock); ret = !list_empty(&iommu_device_list); spin_unlock(&iommu_device_lock); return ret; } EXPORT_SYMBOL_GPL(iommu_present); Since neither of the two users is really needing anything more than that? Jason _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel