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=52.101.43.57 ARC-Seal: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=pass; t=1793153699; b=jY04LB+Ix5OXc0SpFbKi7EnMaEOvR38agckpKfIg/7KjBsdZ+BYRV8YyVjyOmUjqFxck iRgvVza51rFGwEic/iyxOilB6BsGZfifjcz3smiv8i9owODiRls1egtkOpg3PZE9+yDfj 12RAx6BN6RBSDyQQlWwD1kcpfLLhvnolTqcpW57AotuwtU3pg0LH+p9ieek3zDxMBmKpl PW2wv8YsqFxGuoCEYIWkadwNiE2k2b+qS39R9jmFKK+F/TlK/ecNClVf7+45GTcyvGiFF jykxK62Md08VkmZpoI1LVzfIJm20sIVW/1qjGpzQZ4Rpg0fL4rNjB1sdzEKO4fBNcQg== ARC-Message-Signature: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793153699; h=DMARC-Filter:DKIM-Signature:Received:Received:Message-ID:Date: User-Agent:Subject:Content-Language:To:Cc:References:From:In-Reply-To: Content-Type:Content-Transfer-Encoding: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-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=+d2LcLyFxPzyNEdPohZ/LYvQjMeQMnwgHvoPc2toytU=; b=NvF51Th/IF4B8Ji1OWgMV9YmxO7sAJdsVXsY+BABIRzhtPf9COKXQ/KM4mjLYPM9+yVt 2TCbSRpepSrByx9nKTmKY8SZD7Gc/aeqT59E24YJviYYmWgy0IydY5q5xL1Nx5vqesF1O ef/z3150VMqpjscm2Mbg9SHnI84+DKSbHjHaKsl1qOzp2Ut2LBPhE6vqAvqYiVMRnLgQ1 XUVLIDYE2LnSuHy7VUdVuCADMO8EDSYzOYDrhfz9lTDNVYrwffcm6rEZufMc5rioJZc1D lqKCoFTxnirCh4iZkWBLEupD7Yuzk0mhJtZdwQhCTV6k/Oj9ttF2yVaz1hQ7Vxgmjew== ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass header.d=amd.com header.i=@amd.com header.a=rsa-sha256 header.s=selector1 header.b=m4QIoMYB; arc=pass header.oldest-pass=0 smtp.remote-ip=52.101.43.57 Received: from SJ2PR03CU001.outbound.protection.outlook.com (mail-westusazon11012057.outbound.protection.outlook.com [52.101.43.57]) (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 84939606A31A for ; Wed, 28 Oct 2026 02:14:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 84939606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=amd.com header.i=@amd.com header.a=rsa-sha256 header.s=selector1 header.b=m4QIoMYB ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=H4ASiHqZr7WJnDHyQW4aU0k0uwgmp3+BwEOxqezV4gXqYS8H54cXMRp3lc046E0JQfiLRoCYP9qUuoOv43SBSJyjYwVIb7gPWcc4W5ahvUe9nQrim+IsXLSeaPimwdp9PRV3cdgWnYDmGUz+u/ErfW1hQ1gSOnPGVPb1pVviPlTdGOrHJ7n/Y5OPpg1oUeoMlz97tf/sjB+ZUHu3Z11Sdnl19F6jmVQRiySEqMU3kUK/s192knW7g1hv7A2vs3EZo86OuaHM0rMyX0LrV5qb1xFBtOU4xoze1T65s8RSZ/ZAx4BYYYqh6pyG9dGuiMIFQENC90D22mP3YAuKt3WWvA== 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=+d2LcLyFxPzyNEdPohZ/LYvQjMeQMnwgHvoPc2toytU=; b=Yh+35a7Pp3u0yZ2Da0i/b6B8qF6l2yGimUisgdd1xaxi2baDFzmvlmA41mWIxPGGeBBprieERfA8teeaulc5A/WN8WsKiqqJtv6na1+vg0F/BqWKjS+W+9Fb83FAoK66llYBw6HTphJCwjZl2YKW4wb94aqgVik2qbTM5xdqAN6qRmz8r5kJtGwI8gn3vcKjKW03sqc9m0WBml1Ab4AIpz8ojJQ2FKfKEVJg7rd1M+/ZdqK4xAl953qNmdsJQ3A5UdLtHgn8v5oPtMTycKl5Q7HK7WsDjYvmUjQ5cEvreG0eHa8TTIJiNZshm7xPysrOzEY2D2Hz03rlZKzvBzX16A== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=+d2LcLyFxPzyNEdPohZ/LYvQjMeQMnwgHvoPc2toytU=; b=m4QIoMYB45ua+2XauBOU8nfnCjc+6+Yw13wpKAizCSua3k48A90raXaegTV7xjkEXlwjxsgkNs0Lzww+AwzF6Sz3VWaJosdn21IiJv9AGdD5JfPQN8NlJnZOJ2svCSHF0+MG2YZ0VnZGrYluCCwJtJMgD0GC3h/PVfyadog0T+0= Authentication-Results: mx.microsoft.com 1; dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from PH7PR12MB9174.namprd12.prod.outlook.com (2603:10b6:510:2ed::9) by DM4PR12MB5796.namprd12.prod.outlook.com (2603:10b6:8:63::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.546.22; Wed, 28 Oct 2026 02:14:54 +0000 Received: from PH7PR12MB9174.namprd12.prod.outlook.com ([fe80::eaaa:b430:ba9:5dc]) by PH7PR12MB9174.namprd12.prod.outlook.com ([fe80::eaaa:b430:ba9:5dc%7]) with mapi id 15.21.0546.021; Wed, 28 Oct 2026 02:14:54 +0000 Message-ID: <76b577d9-e8ce-45d5-9330-564411cc099d@amd.com> Date: Tue, 27 Oct 2026 21:14:52 -0500 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/3] drm/amdgpu: reserve 64M stolen memory for Apple 5K iMac Content-Language: en-US To: Richard Lane , Alex Deucher Cc: =?UTF-8?Q?Christian_K=C3=B6nig?= , amd-gfx@lists.freedesktop.org, Alex Deucher , Harry Wentland , Leo Li , Rodrigo Siqueira , David Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <6f79a3e2-5510-4018-aabd-45fcdf5dcbb3@amd.com> <138497f6-2271-4229-87f1-4e42e9d2b581@gmail.com> From: Mario Limonciello In-Reply-To: <138497f6-2271-4229-87f1-4e42e9d2b581@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: SN7P222CA0004.NAMP222.PROD.OUTLOOK.COM (2603:10b6:806:124::18) To PH7PR12MB9174.namprd12.prod.outlook.com (2603:10b6:510:2ed::9) 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: PH7PR12MB9174:EE_|DM4PR12MB5796:EE_ X-MS-Office365-Filtering-Correlation-Id: fb1f2e37-e243-4eca-01dc-08df3499416a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|366016|1800799024|376014|261022105027099003|261009223027099003|261021121427099003|261022075727099003|261022115727099003|261021123027099003|10067099003|56012099006|3023799007|261026140227099003|6133799003|22082099003|18002099003|261026121527099003|11063799006|4143699003; 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:PH7PR12MB9174.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(23010399003)(366016)(1800799024)(376014)(261022105027099003)(261009223027099003)(261021121427099003)(261022075727099003)(261022115727099003)(261021123027099003)(10067099003)(56012099006)(3023799007)(261026140227099003)(6133799003)(22082099003)(18002099003)(261026121527099003)(11063799006)(4143699003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ZjZVb1V1VmRpbU1wZ2w1TjdSQXpGR3JWejgxU1pabWdkc0kwcU9HV3NNVU54?= =?utf-8?B?Y24wSkhrSGdsenVaZmUzb0FhSSt3UWQyN0ROS2pNQjZRamdyYUFaSWxIMjgz?= =?utf-8?B?Yi90Sjd5OS9VSVoyb2JZOXg2MW5Idldvam5TTlJlMk5oSENVQk03dkQxSFlS?= =?utf-8?B?aUFoMmliOUt2RlpPR2NWYjNmdDRhMFcvNGlWcVZ3TGVqdVUxSmM3L0UwSUxo?= =?utf-8?B?OW44SjBpUEFHSHRMMCtLOVA2WFR0M3p3eHFHNFhZSnh5Y2NQbEgxN0hWRE9r?= =?utf-8?B?dVVDb3J2b0pMVjlOYmdLTWU2TXJabUpxcElNeFNaTnE4WWFKRFViTU4xSkVM?= =?utf-8?B?Vi9FVU9TM0xENGlTUlJ0NDZBRnVsd2hnMXNyTWR0V2NoLzgwUmRsaXVHRFQw?= =?utf-8?B?R0JLd3Zla25ObDhMejh6NDVWUUZJS2UyblRzZXo2RU1YNlVXaHIzL3I4RTlK?= =?utf-8?B?ZkpOa3BPbVF4bXlEaW5RK1lMMm1ySjN4REFtQWtTNlluZnBYaEFiVWpmMkxr?= =?utf-8?B?cVJMVU9wYzFKUnlsWVBCVUNjNHRucmVIbkp6QlNQNFpTSkFvTmY3SGtQQko4?= =?utf-8?B?YnZReG9zUVRYT0RqcHRIT2lNUE5sRk84b1kvSEZjWHF1WmxGYy9uU0dMSmRo?= =?utf-8?B?NUpFSnVEdVIraDQ4Q1ZjQ1pUWWZKK09XaWdCUWZoYVRjVXA2Z2pQSDRmQ3ZV?= =?utf-8?B?aU5WM3V3SlFEMEFDM1B6SHJiWlJsN3owWUNyd28zTGYrWkowb01ZKzl1S0hK?= =?utf-8?B?eXJDZTNueU54SUdJR3RPZ1p4M2JLMngveTVDUURLSU9ZcEZaekV1MkxQd0ND?= =?utf-8?B?a2NmcnFKREkyVlJQWjVMcmZvVkZlcHRqTnF3L01jZ1RpU21vRXBZYW1GcUFW?= =?utf-8?B?ZFZQOVRHR2pvTWVzRk9yMEpCNGVSY0ZNK08weGpyQW01NGlTVkM0aGM1TTY3?= =?utf-8?B?aEoveW5EUlUxeVlDN2NRTG1uVXR5Wk0wWGIzNTlTV2ZtK1ZlRkZkQlpWYzVy?= =?utf-8?B?SVZKdEVubWFoVkhqb1lpajlXVE1uV0ZFVlJ2dlg0YitwRnhUOVJWM3FZTmV1?= =?utf-8?B?cTk0cnB1MDk1VjRBNFpjNjh2OU5kc0ZySFFPRU92VTl0eFl4M1RLOWdwYko3?= =?utf-8?B?aFpwNS9VS1hSQXNtTFJ4dllFaElIN2E1YTBGenFETnNob3FiakQ2UkpxVTVz?= =?utf-8?B?VFlpYUgvSWtUeS81Y3d6UDhseTBzaUNnalR2bU1DbktFMHJLYWYxL1EvSWZh?= =?utf-8?B?QVJuMFl5WE1TTkVTUHdJcFIzamRzUG1LTktKamR1aEZDb1AxZkxJS1FMZ3Jh?= =?utf-8?B?OE9tMEFmaXVHYkFYNXpERHBtL3BKbDZWT3FyNXR6dm91cUM1eTFKeGt6Z29P?= =?utf-8?B?emtrN2lWQjhXVVVydTBCUldoMnNWOXdSS0JvVlZWWTdBdVBKOXVQNjFkaWhp?= =?utf-8?B?R2dldUVTKytqUEJkc3c4b1gwVXVBNXNFYmpMUXNvMEVLcXUzUnNNeFhWZWxp?= =?utf-8?B?YjZvclEzOSsxTWNIOGZ5TG1oV2VBRlZHYUNKRTlNNGdSN01mU1hwUk5hcnVM?= =?utf-8?B?OHJ0VmRJNDNZMGNlS0o1ZHdmSWFmcDhvMm5hQXZUWkxEL1Rya1pNRlFIQ2hp?= =?utf-8?B?Q2VPYkNmY1MvcWN1UjdYTUhGRUJ2NDJ3NXVHaWRKdldRb1hGR2lnbStKQ3JI?= =?utf-8?B?Wk42Tnk5SWRmanBVWGZjMXorZkg3M2pZM0NmNFVoaTlUL2hzeTVQWXJTN1Ry?= =?utf-8?B?Sm8xZmpuYW9xMzJBNWZHL3FaalRYUFQvcU03R3pyQ1ZGKzMvVVh4ZUo5eXFB?= =?utf-8?B?MndIK2RTRGVwKzZESklnOGpjVTNjZWlYYnA2Z3NzWUU3eWYydTFVbHFHcXdm?= =?utf-8?B?b3d3Q3RBZjB4WmpvOTA1ODhBandKWEhibU5LMGNKOEZodXp6SW13akdLSHhn?= =?utf-8?B?RTJCcVdSbmpMWTMyQkxhaFVLSmNnNjhTZktXbTlIRnZxcE81UnFOSXhiZklj?= =?utf-8?B?U3N1N0F1c3VwU2hDbHJaVnlwMU9VL0x4WThSVlpaVUxSWHRIZ0pJRWlyenFu?= =?utf-8?B?amlnNDBSV2JYeVFaeXk5bWdReXhIa3Z1S09iNW8zRkNSbExTUWVxUXQ5ZzMz?= =?utf-8?B?R3d3SkFocTQrK0tlYkp4bFFsRVJnWWIrbzhFeWZQVkZuamZYQVEwRUdxS0hP?= =?utf-8?B?R0czVFgxMHJkZ3pPcE0vK3VITzlFakVuYXFYZER5Zll4ZUdmVVh6dkRHUGtk?= =?utf-8?B?YzFGVDM3NndLbTBmL2psMzYxdTVDeTk0QWdaZVFoWEhVbkxUZkF5aVZhL0Zq?= =?utf-8?B?R3BSRXV3YlNkaUhwTVAxRlM5NkpQUkhhTXlsMHRyL0lTbzVXN1BqZz09?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: fb1f2e37-e243-4eca-01dc-08df3499416a X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB9174.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Oct 2026 02:14:54.4059 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: WhJAXBdKfnByzuglc4BtyXn4wuG4YqHON0lzFvD8RB+K6e/O+S6Itj71JB1iLKHt4uRVMgqA1CYZGoSy0h+CSw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5796 On 10/27/26 18:59, Richard Lane wrote: > On 27/10/2026 13:37, Alex Deucher wrote: >> On Tue, Oct 27, 2026 at 9:16 AM Mario Limonciello >> wrote: >>> >>> >>> >>> On 10/27/26 07:57, Alex Deucher wrote: >>>> On Tue, Oct 27, 2026 at 8:21 AM Christian König >>>> wrote: >>>>> >>>>> On 10/26/26 23:46, Richard Lane wrote: >>>>>> Apple 27" 5K iMacs report a single 2560x2880 tile (28.125 MiB) in >>>>>> VIEWPORT_SIZE while scanning out up to 64 MiB across the relocated EFI >>>>>> framebuffer. >>>>>> >>>>>> Override the stolen VGA memory allocation size to 64 MiB when matching >>>>>> PCI_VENDOR_ID_APPLE with a 2560x2880x4 viewport size to prevent >>>>>> framebuffer corruption during boot handover. >>>>> >>>>> Hacks like those are usually a big no-go. >>>>> >>>>> Why is that framebuffer handling not working with DC out of the box? >>>> >>>> The GMC IP code reserves the memory used by the display hardware from >>>> the pre-OS console. The gmc get_vbios_fb_size() callback looks to see >>>> what display viewport was set by the pre-OS environment. If the Macs >>>> need a workaround, that's where it should go. Since these displays >>>> require multiple display pipes, my guess is you need to double the >>>> allocation in that case since the current code just checks the first >>>> pipe. >>> >>> >>> Could this also be a logic error in that callback? Would it be worth >>> double checking all the register values in that callback for this system? >>> >>> I know for example there are a few different IP specific implementations >>> in gmc_v9_0_get_vbios_fb_size(). >> >> Not likely. I suspect the issue is that these systems use two display >> pipes so we only reserve enough memory to cover half of the display. >> On PCs the vbios never sets up MST. >> >> Alex >> > > I tested doubling the allocation in gmc_v8_0_get_vbios_fb_size(): > > if (adev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE && > size == (2560 * 2880 * 4)) > size *= 2; > > That eliminated the corruption across the middle (45-60%) of the screen, > but still left a band of corruption along the very bottom (95-100%) of > the screen. > > Dumping the DCE registers inside gmc_v8_0_get_vbios_fb_size() on the > iMac17,1 showed: > > vram_start = 0xf400000000, d1vga = 0x0 > CRTC0: grph_en=0x1 surf_hi=0xf4 surf_lo=0x300000 pitch=5120 vp_size=2560x2880 > CRTC1: grph_en=0x80000000 surf_hi=0x0 surf_lo=0x0 pitch=0 vp_size=0x0 > > Even though only CRTC0 is active at EFI boot with a 2560x2880 viewport, > Apple's EFI allocates a full 5120-pixel stride surface (mmGRPH_PITCH) and places > mmGRPH_PRIMARY_SURFACE_ADDRESS at a 3 MiB offset (0x300000) from > vram_start. > > Because CRTC0 scans out 2880 lines at a 5120-pixel pitch starting at > offset 3 MiB, the active pre-OS scanout spans [3 MiB, 59.25 MiB) in VRAM: > - Reserving 2560 * 2880 * 4 (28.125 MiB) places permanent driver BOs at > ~28.125..32 MiB, corrupting the middle (40-60%) of the screen. > - Reserving 2 * 2560 * 2880 * 4 (56.25 MiB) places those BOs at > ~56.25..59.25 MiB, leaving the final 3 MiB exposed due to the 0x300000 > surface offset and corrupting the bottom (95-100%) of the screen. > - Accounting for the 5120 pitch and the 0x300000 surface offset reserves > the full 59.25 MiB span and eliminates the corruption completely. > > For v2 of the patch, which of the following two approaches in both > gmc_v7_0/v8_0_get_vbios_fb_size() would you prefer? Both tested working. My feeling is that Option A is less magical. I'd actually wonder if we should be doing this more widely. I'd *think* the same problem could happen on a non-Apple display that behaves similarly. > > Option A (change whole function): > > static unsigned gmc_v8_0_get_vbios_fb_size(struct amdgpu_device *adev) > { > u32 d1vga_control = RREG32(mmD1VGA_CONTROL); > unsigned size; > > if (REG_GET_FIELD(d1vga_control, D1VGA_CONTROL, D1VGA_MODE_ENABLE)) { > size = AMDGPU_VBIOS_VGA_ALLOCATION; > } else { > u32 viewport = RREG32(mmVIEWPORT_SIZE); > - size = (REG_GET_FIELD(viewport, VIEWPORT_SIZE, VIEWPORT_HEIGHT) * > - REG_GET_FIELD(viewport, VIEWPORT_SIZE, VIEWPORT_WIDTH) * 4); > + size = REG_GET_FIELD(viewport, VIEWPORT_SIZE, VIEWPORT_HEIGHT) * > + RREG32(mmGRPH_PITCH) * 4; > + if (size) > + size += RREG32(mmGRPH_PRIMARY_SURFACE_ADDRESS) - > + lower_32_bits(adev->gmc.vram_start); > } > > return size; > } > > Option B (add Apple 5K iMacs quirk): > > static unsigned gmc_v8_0_get_vbios_fb_size(struct amdgpu_device *adev) > { > u32 d1vga_control = RREG32(mmD1VGA_CONTROL); > unsigned size; > > if (REG_GET_FIELD(d1vga_control, D1VGA_CONTROL, D1VGA_MODE_ENABLE)) { > size = AMDGPU_VBIOS_VGA_ALLOCATION; > } else { > u32 viewport = RREG32(mmVIEWPORT_SIZE); > size = (REG_GET_FIELD(viewport, VIEWPORT_SIZE, VIEWPORT_HEIGHT) * > REG_GET_FIELD(viewport, VIEWPORT_SIZE, VIEWPORT_WIDTH) * 4); > + > + if (adev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE && > + size == (2560 * 2880 * 4)) > + size = size * 2 + RREG32(mmGRPH_PRIMARY_SURFACE_ADDRESS); > } > > return size; > } > > > Richard > >>> >>>> >>>> Alex >>>> >>>>> >>>>> Regards, >>>>> Christian. >>>>> >>>>>> >>>>>> Signed-off-by: Richard Lane >>>>>> --- >>>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 10 +++++++++- >>>>>> 1 file changed, 9 insertions(+), 1 deletion(-) >>>>>> >>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >>>>>> index 4204c3c750a8..8b196fbfa724 100644 >>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >>>>>> @@ -1232,7 +1232,15 @@ void amdgpu_gmc_init_vga_resv_regions(struct amdgpu_device *adev) >>>>>> } else { >>>>>> size = amdgpu_gmc_get_vbios_fb_size(adev); >>>>>> >>>>>> - if (adev->mman.keep_stolen_vga_memory) >>>>>> + /* >>>>>> + * Apple 5K iMacs report one 2560x2880 tile in VIEWPORT_SIZE >>>>>> + * while scanning out up to 64M across the relocated EFI >>>>>> + * framebuffer. >>>>>> + */ >>>>>> + if (adev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE && >>>>>> + size == (2560 * 2880 * 4)) >>>>>> + size = 64U * 1024 * 1024; >>>>>> + else if (adev->mman.keep_stolen_vga_memory) >>>>>> size = max(size, (unsigned)AMDGPU_VBIOS_VGA_ALLOCATION); >>>>>> } >>>>>> >>>>>> -- >>>>>> 2.55.0 >>>>> >>> >