From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=pass header.oldest-pass=0 smtp.remote-ip=52.101.43.21 ARC-Seal: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=pass; t=1793971609; b=4hHiaol0TUf0JT0ZtoUsIP52Tu/2QWBSMHvVQMSitLlMqj6E0+Bd12vA/zvb+CUJQELZ o43IwW7yzq3WlJJXd50dY07rUnv7jyuIHeGPKgR1vPxY+H4gm/n1WlbJgd6gsebtRIvgl n16w/F1nRR5Lv9W1pQGp2KlyY4Y25WDGf2ReBHzsCxlXpGf86Igdu3TjlP+iI4V5ye9zC eFB5LAH1mNmkf19NiU/J6B0w5cOLwmIIsrlYgPPRu9R2zPdgpuH9Sv91fUW8STSWHhF2O AfHQlW3wMtQx1bcSYrPFNZBc9ng8ML0fyhO8CIv89YG5UTN5vdEoEWHdJg2GcebscvQ== ARC-Message-Signature: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793971609; h=DMARC-Filter:DKIM-Signature:Received:Received: Content-Transfer-Encoding:Content-Type:Date:Message-Id:Subject:From: To:Cc:References:In-Reply-To:X-ClientProxiedBy:MIME-Version: X-MS-PublicTrafficType:X-MS-TrafficTypeDiagnostic: X-MS-Office365-Filtering-Correlation-Id:X-MS-Exchange-SenderADCheck: X-MS-Exchange-AntiSpam-Relay:X-Microsoft-Antispam: X-Microsoft-Antispam-Message-Info:X-Forefront-Antispam-Report: X-MS-Exchange-AntiSpam-MessageData-ChunkCount: X-MS-Exchange-AntiSpam-MessageData-0: X-MS-Exchange-AntiSpam-MessageData-1:X-OriginatorOrg: X-MS-Exchange-CrossTenant-Network-Message-Id: X-MS-Exchange-CrossTenant-AuthSource:X-MS-Exchange-CrossTenant-AuthAs: X-MS-Exchange-CrossTenant-OriginalArrivalTime: X-MS-Exchange-CrossTenant-FromEntityHeader: X-MS-Exchange-CrossTenant-Id:X-MS-Exchange-CrossTenant-MailboxType: X-MS-Exchange-CrossTenant-UserPrincipalName: X-MS-Exchange-Transport-CrossTenantHeadersStamped; bh=R/1xXH9/Rxx4kUnNVxhzqm8q7hTRf++5F5+6IpcmYM0=; b=ERl9bU9lWEfVoO9o1r4RoCqYjSAgzp6zayL3lelMz7JrkKouUfg4dVqY/0CBrgUKc80E UXrQSUpE/yEOAsjAPOb1o30wOFNhs5Ya2bd3+Kn8WGzdrBmJ/JjuNi/V+TlLhh/QxD/Sl R+ecYt4X+TBRAI/rd9xwRX3cFZGlMAba5FoXBPJp8hATYUbJZmvVUJI3cklJgGjSHQ7X3 swJnUiFx/1OI0QR63/BJUw2+1HzI4u9WUOiRpJlkUhHEZPI/QrvYlZGc1F/sWrMwrySoA 3wiUAW8h50md3zpDfP4pkdPxFO3KOuTeRydU26zEvyZdVs3IDYIwvf/qvvztjsc7uwA== ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass header.d=Nvidia.com header.i=@Nvidia.com header.a=rsa-sha256 header.s=selector2 header.b=Ev2DHpn5; arc=pass header.oldest-pass=0 smtp.remote-ip=52.101.43.21 Received: from SJ2PR03CU001.outbound.protection.outlook.com (mail-westusazon11012021.outbound.protection.outlook.com [52.101.43.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (secp384r1) server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B38B5606A326; Fri, 6 Nov 2026 13:26:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B38B5606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=Nvidia.com header.i=@Nvidia.com header.a=rsa-sha256 header.s=selector2 header.b=Ev2DHpn5 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=VXft319wNrvJ8bZBwa6Ub48tkMdMmGjOCjFHws8ZeF4Kbh0K69Lu9q5wTyB1fUvKi1czCOZccs80Eo9umLbEVAKHPvlcA7naGubvwIok/viBH+9F3WPDRT2l0l8td+DwWF2HrbmcYvSdwufMuV9JO7noghL2wKnVZ2gruVE7QTjnrbYyGw7S4vuPDoIISIpU2NpQhbQS8GJ2qV/7vAu3HBk90bDNEAsCurjhNpe0ylBwcxuoXYxXmtpePQA/hM/4XNQ8QIWFq7aorb4ne9D9FqdNIn/HuO6KBb009/qPqvqMJROBXMSoXFuyH3SAMgy20DGEdDh6Ng1/jbzrsKN/5Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=R/1xXH9/Rxx4kUnNVxhzqm8q7hTRf++5F5+6IpcmYM0=; b=bCmNTenE+e6Nh9xSDiEuSaR0+qrzxobqyPKbMzoAPkNU97vaBv6HSxXMNQRDREUhJyCKV1Wbjlupq3jhDriG3So+e6sZ3VGvBju0qqpDt5YztqGxM4H/eimH1BZg9Vx5yH3qN5qkRYLLF2mFOh/2FBLB5L0QAIuk6tv5C7yK574ZCEcuEH/leIgfUvUvvd0mOV2xmYe5++Yn8MzJ7v0+v0/JGgIJTMjQ7rGWlNUOyykWQbJIEkw9ZehLnUFm17xf11gMTofQJY0B9lK8qDOEGrY3LPY20jCoUw9mXIchnT4ZBZAg85MopB5mO/A39LfMFtjGiUJatqRyyDBe5c8DdQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=R/1xXH9/Rxx4kUnNVxhzqm8q7hTRf++5F5+6IpcmYM0=; b=Ev2DHpn5Gw0weRQLOKHv9DrFMgNpELpb7dTkLAbIWpEK3qTDGS43Nr9aHicbbUMsSdh8n0ZhDYb87/YI2GZr8bZbJTqzF5Gby49Pe5TZ6Lr7dramN1pjAzc4Q8uGfTAapXaE7VOOMYaQtfu564k0QLGOyVIkPgZ1Oh3xYSQ+d0bUlHQUi92ZawtNc+hcBbeaB/sTqBgr5yAGkd8S106pGvWfjafC5q3BO/JgnmciXyXoP9XH/IR7rzKstNLWoG5f4Wc7mA/DZDnv4GvHDEqzD2iQhNllRj8JLmqL2S91pYHxjQRIIdR3lXCILSK1EFB/hgFWtLlecVVdBuXGBplqXg== Authentication-Results: mx.microsoft.com 1; dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from MW4PR12MB6873.namprd12.prod.outlook.com (2603:10b6:303:20c::17) by DM4PR12MB6661.namprd12.prod.outlook.com (2603:10b6:8:b7::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.592.10; Fri, 6 Nov 2026 13:26:42 +0000 Received: from MW4PR12MB6873.namprd12.prod.outlook.com ([fe80::a338:bd2c:3a38:ece1]) by MW4PR12MB6873.namprd12.prod.outlook.com ([fe80::a338:bd2c:3a38:ece1%5]) with mapi id 15.21.0592.007; Fri, 6 Nov 2026 13:26:41 +0000 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Fri, 06 Nov 2026 22:26:38 +0900 Message-Id: Subject: Re: [PATCH 5/7] gpu: nova-core: falcon: allow DMEM DMA transfers to request tagging From: "Alexandre Courbot" To: "Eliot Courtney" Cc: "Danilo Krummrich" , "Alice Ryhl" , "David Airlie" , "Simona Vetter" , "John Hubbard" , "Alistair Popple" , "Timur Tabi" , "Zhi Wang" , , , References: <20261103-r000-fw-v1-0-e3d38fc130e3@nvidia.com> <20261103-r000-fw-v1-5-e3d38fc130e3@nvidia.com> In-Reply-To: X-ClientProxiedBy: TYCP286CA0123.JPNP286.PROD.OUTLOOK.COM (2603:1096:400:2b6::11) To MW4PR12MB6873.namprd12.prod.outlook.com (2603:10b6:303:20c::17) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MW4PR12MB6873:EE_|DM4PR12MB6661:EE_ X-MS-Office365-Filtering-Correlation-Id: 4167fb11-68d1-4174-3c6a-08df3c099834 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|23010399003|10070799003|6133799003|22082099003|56012099006|18002099003|3023799007|261026140227099003|261021123027099003|261028144727099003|261021121427099003|261022105027099003|261022115727099003|261021135927099003|261009223027099003|261022075727099003|11063799006|4143699003|10067099003|261102123227099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MW4PR12MB6873.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(23010399003)(10070799003)(6133799003)(22082099003)(56012099006)(18002099003)(3023799007)(261026140227099003)(261021123027099003)(261028144727099003)(261021121427099003)(261022105027099003)(261022115727099003)(261021135927099003)(261009223027099003)(261022075727099003)(11063799006)(4143699003)(10067099003)(261102123227099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 2 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TVlFb29BQThzUGV2bXNQVC8zRVFKc3BQRjVxRkNJbGxYdkZ2aGRrckd5MTNu?= =?utf-8?B?enJRQWNlQXdLUnVzdDN3NU9MZFpla2JEZmFLekN2YUlZbFk3eWEweGdmRm1q?= =?utf-8?B?MHRacW1PTzd4c3kwN2hOT0hGYnFINk9QYU96UGpBdzh0MGh1a04wU0NHMmJo?= =?utf-8?B?eUgwRTB2WE9TZGVacjB2NVFYR3YvWXhYMW91TTVGTkcxNFJBUFQ4eGc3MlEy?= =?utf-8?B?bnVMQzhCbVlkOCtKS0lTMlhMMHRITGJRajd5MGpQaEhVaFNqZ3pDZHNoWWRq?= =?utf-8?B?TkhycGF3UWtrdVpUdEY0V2tmd2VCc0o1d0JKczE4VjQ0R1dpbWFRdmdBeGtN?= =?utf-8?B?VkZ1RWlITlMveGRIQWI1ZlhLV1pyUWNLRVpIdWpwdy91VW41VU90OTNLVEwr?= =?utf-8?B?MXo3WnZsS3hCTkdOOENuWmgzZ3NZRURBSFBWL2ZSblVjWW51d2hUUmVqUWJr?= =?utf-8?B?QnFMNFYxK2N2b3YwbFI5cmdpME5DZFhac3gzOGRoMVZmOSthaERQdm9QSEZE?= =?utf-8?B?QWVqd2QvVFhleG1xblJIUjM3VmxmeUJpUERTZW1YZjQ0aWNYZkduT3cwanpB?= =?utf-8?B?bERHZkZVNzNKQjNCTEN4ZFUvbTN5UFZkN1IwMmlNUGk5eldrZ0twVjZoNDVQ?= =?utf-8?B?YmNzckNvSmVqd3d2WnE3UVJCYUE2NFhaQUE0elBadmFiZXFKSlR2L3hwN1Rn?= =?utf-8?B?RzNaNDYzUkQ4N3Q5aXdmNEdYOTVBaXNDZFM2bXRXK1dhVzhPbkZtV0F3ZGZl?= =?utf-8?B?a2VCamZ5VTN5VWdDVmEvUzdQSnpkRW1WNEp4WXpyRjhYVkttYmJzVGEyUmw5?= =?utf-8?B?UGdYcDE0ZXJzeE5ZcmwrS2RtTXI3eGRHRm42dFJlcE5ZbGh5ZE8rZEhSL3cv?= =?utf-8?B?UHgyRVVNYWN0UWJ2RUVYOVZHWVc0cG8xc3FDSDFEMURwSlJMZkpNMGRNNnVO?= =?utf-8?B?N3JiaDNWRXlZYmE5dWUza0drOHhlNVl6V3lPL3pJSENkMUQwdkVkTEQ1bzBR?= =?utf-8?B?TEE4eE5yMHJMLzg0ak1Fc24vTUtIbit1MXNzUDQrRjVjS05haEVvUmd5VUpi?= =?utf-8?B?WmxTV0oxQ3NUY2s2WnQwMVZ5YkVsUEpzYnFwcGo3QkVneFY2eUNad2E4V2pG?= =?utf-8?B?VTlGMUlCcFRxSm4xNmpYMFJOQkpMVVIwc0hrMjI5OGZHT3FiN09pVkc1VEtS?= =?utf-8?B?ZmwySDBhZ0pHZ05vUnZZRlptV0R1SG9uaEtjOGJWMXhZOEpTcXA3K00vVW9L?= =?utf-8?B?QUhTVVJucCtYTGJzWnVHbk55R2dYQU9PYzRZK2hEWkRqTXVXdDU5UitqbDE3?= =?utf-8?B?QXNaZVRrTE81U0pDaHVNVEtXcW54bVVnUXhBeGgzeE0rS3dkQ1NlYlFoNkt4?= =?utf-8?B?VnpSMjQwdzFOVUNGbUFxWnRGWTFSbWlXaTJOOVhJUE5PR3F2TGkxOVpaQUZ6?= =?utf-8?B?UXdCa0NVZCt6empOSnlMbHdnenJrOGswTmwzd1VMOGlDK0lwZlMxbHBXRWp5?= =?utf-8?B?b3lTSDNzek5GVGgzQjA4bDVNSCtyMlRFdVNoVlh1MGtzeTRnSVhXSE9wT1l0?= =?utf-8?B?M0ZNNUNkQVdPdlhHVG8ycGFIbHRtRysyR20ybWRQKzRhTmVaRGNSMWZIQ2hN?= =?utf-8?B?eGFrbmdLYUNLTlhpUVpMS1dnaWN3RG5QcUZvTS9reUR0dnF2T1dKV3dnZHRI?= =?utf-8?B?UzRkTUhQNFdlK1cvYXdZTFhrc1AyeXlGa0JKZXdpMTBYaWJTaTlrM3owSmJp?= =?utf-8?B?ZkdaUUFVT3RUNllpSEZ4RHFXc05JRlVleTZ1LzRPbE5HbWprcnIzSmJ1YUE2?= =?utf-8?B?K0R3azVlVnh1a2FxMzhpUEtJNC96eGRYdkVFSXpmVHQwYS9QUVluU09NK2JT?= =?utf-8?B?SjcrOXU5MFU0Vlo1akFBamxSYnRkQVdURWRsdFg2aGxTcXg5ZkZudmk2YlRx?= =?utf-8?B?MU5oalhraGI3NUtueUpWTDcxQjI2ZU5waEhZbjh1N1B4c3R5dXlnR2QwMzUz?= =?utf-8?B?TndEMDk2YWczTmlWRFNCNjJFUnJjUks3ZU1ZYVlPb244YjJqUVRDbDhQRmZo?= =?utf-8?B?MVprZXE4ajU0LzIxeExNR0w4MURyWlROeE5WZllKMENaS2I1Z0JWUXUwa2RU?= =?utf-8?B?cm9aQ2FaOFZubUF6V0paSzlaMHU5SlM1L3FBbXVGRHp2WmtLWjRiclVxclFx?= =?utf-8?B?S3BBWWltR2J1ZUJpUzhwNzFaUnJ2YjFxdTR1cXRveWRNc3EyVzF6WEQ3MnR4?= =?utf-8?B?TFk4dElxTHpQSHFRS015dTFDMCs1NnpybzFGclA2RXFDblNvblVvOERiVDVz?= =?utf-8?B?L0hma3lwdmg0dTFWODByMXl6MGhXRk5uOEQySHp0RW5uNll6RkFNdzY2dHQr?= =?utf-8?Q?Xrn4ImhPMw7YzzyN52YVt1oijUEHEuVHIIBt/xEGIvqa0?= X-MS-Exchange-AntiSpam-MessageData-1: h0U7jBfzHdx0yA== X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4167fb11-68d1-4174-3c6a-08df3c099834 X-MS-Exchange-CrossTenant-AuthSource: MW4PR12MB6873.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Nov 2026 13:26:41.7770 (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: NEnyXuUJQh26gOMnzyIPH2tyQybxQL2Z6nCZk5KSIDtxC1dXkOt76lmrxEZIYbYijtgyYIhg8VdbrxJMckrFNQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB6661 On Thu Nov 5, 2026 at 10:50 PM JST, Eliot Courtney wrote: > On Tue Nov 3, 2026 at 7:22 PM JST, Alexandre Courbot wrote: >> Add a tag flag to FalconMem::Dmem and set DMATRFCMD's DMTAG bit from it. >> >> This is needed for the r000 load-and-execute event which specifies >> whether DMEM should be tagged or not. >> >> No functional change intended. >> >> Signed-off-by: Alexandre Courbot > > It would be nice if this explained what the tagging was. > >> --- >> drivers/gpu/nova-core/falcon.rs | 20 +++++++++++++------- >> drivers/gpu/nova-core/regs.rs | 2 +- >> 2 files changed, 14 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/gpu/nova-core/falcon.rs b/drivers/gpu/nova-core/fal= con.rs >> index 1bceb38c33c6..f48f2eabab0f 100644 >> --- a/drivers/gpu/nova-core/falcon.rs >> +++ b/drivers/gpu/nova-core/falcon.rs >> @@ -131,8 +131,9 @@ pub(crate) enum FalconMem { >> /// Non-Secure Instruction Memory. >> #[expect(unused)] >> ImemNonSecure, >> - /// Data Memory. >> - Dmem, >> + /// Data Memory. If `tag` is set, a transfer into DMEM also tags ea= ch block with its source >> + /// offset, which is then the DMEM virtual address of the image. >> + Dmem { tag: bool }, >> } >> =20 >> bounded_enum! { >> @@ -529,9 +530,9 @@ fn dma_wr( >> // code addresses in the firmware (and the boot vector) are vir= tual. >> // >> // For DMEM, the start offset is folded into the DMA address. >> - let (src_start, dma_start) =3D match target_mem { >> - FalconMem::ImemSecure | FalconMem::ImemNonSecure =3D> (load= _offsets.src_start, 0), >> - FalconMem::Dmem =3D> (0, usize::from_safe_cast(load_offsets= .src_start)), >> + let (src_start, dma_start, tag_dmem) =3D match target_mem { >> + FalconMem::ImemSecure | FalconMem::ImemNonSecure =3D> (load= _offsets.src_start, 0, false), >> + FalconMem::Dmem { tag } =3D> (0, usize::from_safe_cast(load= _offsets.src_start), tag), > > I am not sure, but is it correct to have `src_start` as zero for > tag=3D=3Dtrue here? Surely something should change based on the value of = tag > w.r.t. the addressing. Yes, there is indeed a problem, tagged DMEM should behave like IMEM (which is always tagged) here. I'll fix it. The poor variable names are in great part responsible for the confusion, so I'll also introduce a patch renaming them. > >> }; >> =20 >> let dma_address =3D { >> @@ -568,7 +569,8 @@ fn dma_wr( >> =20 >> let cmd =3D regs::NV_PFALCON_FALCON_DMATRFCMD::zeroed() >> .with_size(DmaTrfCmdSize::Size256B) >> - .with_falcon_mem(target_mem); >> + .with_falcon_mem(target_mem) >> + .with_set_dmtag(tag_dmem); > > Instead of taking tag_dmem out of FalconMem and using > .with_set_dmtag(tag_dmem), let `with_falcon_mem` set it? It looks like > it's always just passed through. Good idea!