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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 8E26CC433E0 for ; Wed, 10 Mar 2021 19:02:37 +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 3EBD164FCD for ; Wed, 10 Mar 2021 19:02:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3EBD164FCD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=crapouillou.net 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 AC9FE89CFA; Wed, 10 Mar 2021 19:02:36 +0000 (UTC) Received: from aposti.net (aposti.net [89.234.176.197]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7265F89CFA for ; Wed, 10 Mar 2021 19:02:35 +0000 (UTC) Date: Wed, 10 Mar 2021 19:02:22 +0000 From: Paul Cercueil Subject: Re: [PATCH v2 0/5] Add option to mmap GEM buffers cached To: Thomas Zimmermann Message-Id: In-Reply-To: References: <20210307202835.253907-1-paul@crapouillou.net> MIME-Version: 1.0 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 , linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, od@zcrc.me, dri-devel@lists.freedesktop.org, Sam Ravnborg Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Thomas, Le lun. 8 mars 2021 =E0 9:41, Thomas Zimmermann a = =E9crit : > Hi Paul, > = > having individual functions for each mode only makes sense if the = > decision is at compile time. But in patch 5, you're working around = > your earlier design by introducing in-driver helpers that select the = > correct CMA function. > = > In SHMEM helpers we have the flag map_wc in the GEM structure that = > selects the pages caching mode (wc vs uncached). I think CMA should = > use this design as well. Have a map_noncoherent flag in the CMA GEM = > object and set it from the driver's implementation of = > gem_create_object. Is that a new addition? That severely reduces the patchset size, which = is perfect. I'll send a V3 then. Cheers, -Paul > And in the long run, we could try to consolidate all drivers/helpers = > mapping flags in struct drm_gem_object. > = > Best regards > Thomas > = > Am 07.03.21 um 21:28 schrieb Paul Cercueil: >> Rework of my previous patchset which added support for GEM buffers >> backed by non-coherent memory to the ingenic-drm driver. >> = >> Having GEM buffers backed by non-coherent memory is interesting in >> the particular case where it is faster to render to a non-coherent >> buffer then sync the data cache, than to render to a write-combine >> buffer, and (by extension) much faster than using a shadow buffer. >> This is true for instance on some Ingenic SoCs, where even simple >> blits (e.g. memcpy) are about three times faster using this method. >> = >> For the record, the previous patchset was accepted for 5.10 then had >> to be reverted, as it conflicted with some changes made to the DMA = >> API. >> = >> This new patchset is pretty different as it adds the functionality to >> the DRM core. The first three patches add variants to existing = >> functions >> but with the "non-coherent memory" twist, exported as GPL symbols. = >> The >> fourth patch adds a function to be used with the damage helpers. >> Finally, the last patch adds support for non-coherent GEM buffers to = >> the >> ingenic-drm driver. The functionality is enabled through a module >> parameter, and is disabled by default. >> = >> Cheers, >> -Paul >> = >> Paul Cercueil (5): >> drm: Add and export function drm_gem_cma_create_noncoherent >> drm: Add and export function drm_gem_cma_dumb_create_noncoherent >> drm: Add and export function drm_gem_cma_mmap_noncoherent >> drm: Add and export function drm_gem_cma_sync_data >> drm/ingenic: Add option to alloc cached GEM buffers >> = >> drivers/gpu/drm/drm_gem_cma_helper.c | 223 = >> +++++++++++++++++++--- >> drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 49 ++++- >> drivers/gpu/drm/ingenic/ingenic-drm.h | 4 + >> drivers/gpu/drm/ingenic/ingenic-ipu.c | 14 +- >> include/drm/drm_gem_cma_helper.h | 13 ++ >> 5 files changed, 273 insertions(+), 30 deletions(-) >> = > = > -- > Thomas Zimmermann > Graphics Driver Developer > SUSE Software Solutions Germany GmbH > Maxfeldstr. 5, 90409 N=FCrnberg, Germany > (HRB 36809, AG N=FCrnberg) > Gesch=E4ftsf=FChrer: Felix Imend=F6rffer > = _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel