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 X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 B5730C433E0 for ; Fri, 15 May 2020 06:58:09 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8E19F206F1 for ; Fri, 15 May 2020 06:58:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E19F206F1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 07F696EBE1; Fri, 15 May 2020 06:58:09 +0000 (UTC) Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id E19A36EBE1 for ; Fri, 15 May 2020 06:58:07 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 27753AD11; Fri, 15 May 2020 06:58:09 +0000 (UTC) Subject: Re: [PATCH 1/2] drm/shmem: Use cached mappings by default To: Rob Herring , Daniel Vetter References: <20200513150312.21421-1-tzimmermann@suse.de> <20200513150312.21421-2-tzimmermann@suse.de> <20200514124050.GV206103@phenom.ffwll.local> From: Thomas Zimmermann Autocrypt: addr=tzimmermann@suse.de; keydata= mQENBFs50uABCADEHPidWt974CaxBVbrIBwqcq/WURinJ3+2WlIrKWspiP83vfZKaXhFYsdg XH47fDVbPPj+d6tQrw5lPQCyqjwrCPYnq3WlIBnGPJ4/jreTL6V+qfKRDlGLWFjZcsrPJGE0 BeB5BbqP5erN1qylK9i3gPoQjXGhpBpQYwRrEyQyjuvk+Ev0K1Jc5tVDeJAuau3TGNgah4Yc hdHm3bkPjz9EErV85RwvImQ1dptvx6s7xzwXTgGAsaYZsL8WCwDaTuqFa1d1jjlaxg6+tZsB 9GluwvIhSezPgnEmimZDkGnZRRSFiGP8yjqTjjWuf0bSj5rUnTGiyLyRZRNGcXmu6hjlABEB AAG0J1Rob21hcyBaaW1tZXJtYW5uIDx0emltbWVybWFubkBzdXNlLmRlPokBVAQTAQgAPhYh BHIX+6yM6c9jRKFo5WgNwR1TC3ojBQJbOdLgAhsDBQkDwmcABQsJCAcCBhUKCQgLAgQWAgMB Ah4BAheAAAoJEGgNwR1TC3ojR80H/jH+vYavwQ+TvO8ksXL9JQWc3IFSiGpuSVXLCdg62AmR irxW+qCwNncNQyb9rd30gzdectSkPWL3KSqEResBe24IbA5/jSkPweJasgXtfhuyoeCJ6PXo clQQGKIoFIAEv1s8l0ggPZswvCinegl1diyJXUXmdEJRTWYAtxn/atut1o6Giv6D2qmYbXN7 mneMC5MzlLaJKUtoH7U/IjVw1sx2qtxAZGKVm4RZxPnMCp9E1MAr5t4dP5gJCIiqsdrVqI6i KupZstMxstPU//azmz7ZWWxT0JzgJqZSvPYx/SATeexTYBP47YFyri4jnsty2ErS91E6H8os Bv6pnSn7eAq5AQ0EWznS4AEIAMYmP4M/V+T5RY5at/g7rUdNsLhWv1APYrh9RQefODYHrNRH UE9eosYbT6XMryR9hT8XlGOYRwKWwiQBoWSDiTMo/Xi29jUnn4BXfI2px2DTXwc22LKtLAgT RjP+qbU63Y0xnQN29UGDbYgyyK51DW3H0If2a3JNsheAAK+Xc9baj0LGIc8T9uiEWHBnCH+R dhgATnWWGKdDegUR5BkDfDg5O/FISymJBHx2Dyoklv5g4BzkgqTqwmaYzsl8UxZKvbaxq0zb ehDda8lvhFXodNFMAgTLJlLuDYOGLK2AwbrS3Sp0AEbkpdJBb44qVlGm5bApZouHeJ/+n+7r 12+lqdsAEQEAAYkBPAQYAQgAJhYhBHIX+6yM6c9jRKFo5WgNwR1TC3ojBQJbOdLgAhsMBQkD wmcAAAoJEGgNwR1TC3ojpfcIAInwP5OlcEKokTnHCiDTz4Ony4GnHRP2fXATQZCKxmu4AJY2 h9ifw9Nf2TjCZ6AMvC3thAN0rFDj55N9l4s1CpaDo4J+0fkrHuyNacnT206CeJV1E7NYntxU n+LSiRrOdywn6erjxRi9EYTVLCHcDhBEjKmFZfg4AM4GZMWX1lg0+eHbd5oL1as28WvvI/uI aMyV8RbyXot1r/8QLlWldU3NrTF5p7TMU2y3ZH2mf5suSKHAMtbE4jKJ8ZHFOo3GhLgjVrBW HE9JXO08xKkgD+w6v83+nomsEuf6C6LYrqY/tsZvyEX6zN8CtirPdPWu/VXNRYAl/lat7lSI 3H26qrE= Message-ID: <6cec8a8a-d642-cd93-906a-eafab49a12d7@suse.de> Date: Fri, 15 May 2020 08:58:02 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , Sam Ravnborg , Emil Velikov , dri-devel , Gerd Hoffmann , Sean Paul Content-Type: multipart/mixed; boundary="===============1352795955==" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --===============1352795955== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="UBMm4bsSEL8jxi16lQOoDXTIGMPp5vkha" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --UBMm4bsSEL8jxi16lQOoDXTIGMPp5vkha Content-Type: multipart/mixed; boundary="Djc63hBi2kwfWobWMAHzMCflrJ5qRRtzK"; protected-headers="v1" From: Thomas Zimmermann To: Rob Herring , Daniel Vetter Cc: Sam Ravnborg , David Airlie , Emil Velikov , dri-devel , Gerd Hoffmann , Sean Paul Message-ID: <6cec8a8a-d642-cd93-906a-eafab49a12d7@suse.de> Subject: Re: [PATCH 1/2] drm/shmem: Use cached mappings by default References: <20200513150312.21421-1-tzimmermann@suse.de> <20200513150312.21421-2-tzimmermann@suse.de> <20200514124050.GV206103@phenom.ffwll.local> In-Reply-To: --Djc63hBi2kwfWobWMAHzMCflrJ5qRRtzK Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable Hi Am 14.05.20 um 22:36 schrieb Rob Herring: > On Thu, May 14, 2020 at 7:40 AM Daniel Vetter wrote: >> >> On Wed, May 13, 2020 at 05:03:11PM +0200, Thomas Zimmermann wrote: >>> SHMEM-buffer backing storage is allocated from system memory; which i= s >>> typically cachable. Currently, only virtio uses cachable mappings; ud= l >>> uses its own vmap/mmap implementation for cachable mappings. Other >>> drivers default to writecombine mappings. >> >> I'm pretty sure this breaks all these drivers. quick grep on a few >> functions says this is used by lima, panfrost, v3d. And they definitel= y >> need uncached/wc stuff afaiui. Or I'm completely missing something? >=20 OK. I think I'll just make a patch that adds a .gem_create_object helper that sets the map_cached flag. So drivers can opt-in. > Yes, that would be my guess. DMA is usually non-coherent on Arm. Can one of you give me some pointer to what you're looking at? For example, I grepped for use of vmap within lima and only found [1]. That's a for memcpy with no DMA involved. There's got to be something I'm missing. Best regards Thomas [1] https://cgit.freedesktop.org/drm/drm-tip/tree/drivers/gpu/drm/lima/lima_s= ched.c#n391 >=20 > Rob >=20 --=20 Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 N=C3=BCrnberg, Germany (HRB 36809, AG N=C3=BCrnberg) Gesch=C3=A4ftsf=C3=BChrer: Felix Imend=C3=B6rffer --Djc63hBi2kwfWobWMAHzMCflrJ5qRRtzK-- --UBMm4bsSEL8jxi16lQOoDXTIGMPp5vkha Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEchf7rIzpz2NEoWjlaA3BHVMLeiMFAl6+PXoACgkQaA3BHVML eiMbPAf/TDVeDZUXmonq4pRC5yW1mwingvAuJjklXUwyt05TJbs1xPXiGBnw6Dlz gE8sUVayOTgs1kTfFCo1SunH7vMD3nwhww6fx50Q60v99SGf4vDOk1rwGE54O+ya gseH8uP0r2RrgNmboRl7wJe8CBajPFnXXL08OcjyD1MGpoFF1J6F05UXQf2KTyB7 rTLDFCGiMUrili7MlkPoS8gxL0KLpNIa7AATMDOsCuLKG3XOIXruRHQM/iYlYpyX vBLz4oWxhmJxeeMz5MXd6VYSnuUQ/TxHlnYqeLMTW7THK7M0MUgHhZ9Rbzigl5i6 IhGZskimZFWzFoG0CWpgz1GaZSaBpw== =U1X2 -----END PGP SIGNATURE----- --UBMm4bsSEL8jxi16lQOoDXTIGMPp5vkha-- --===============1352795955== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel --===============1352795955==--