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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 08EB6C282DA for ; Tue, 16 Apr 2019 12:43:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1F11205ED for ; Tue, 16 Apr 2019 12:43:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729002AbfDPMnL (ORCPT ); Tue, 16 Apr 2019 08:43:11 -0400 Received: from foss.arm.com ([217.140.101.70]:54244 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727030AbfDPMnK (ORCPT ); Tue, 16 Apr 2019 08:43:10 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CB53B15A2; Tue, 16 Apr 2019 05:43:09 -0700 (PDT) Received: from e110455-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 78ACA3F706; Tue, 16 Apr 2019 05:43:09 -0700 (PDT) Received: by e110455-lin.cambridge.arm.com (Postfix, from userid 1000) id CC9E7680358; Tue, 16 Apr 2019 13:43:07 +0100 (BST) Date: Tue, 16 Apr 2019 13:43:07 +0100 From: Liviu Dudau To: Daniel Vetter Cc: "james qian wang (Arm Technology China)" , "airlied@linux.ie" , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "maxime.ripard@bootlin.com" , nd , "sean@poorly.run" , Ben Davis Subject: Re: [v2,1/2] drm: Add writeback_w,h properties Message-ID: <20190416124307.GQ15144@e110455-lin.cambridge.arm.com> References: <1555078094-6587-2-git-send-email-ben.davis@arm.com> <20190415075922.GA24596@james-ThinkStation-P300> <20190415092045.GO15144@e110455-lin.cambridge.arm.com> <20190416073419.GN2665@phenom.ffwll.local> <20190416091658.GP15144@e110455-lin.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 16, 2019 at 11:55:34AM +0200, Daniel Vetter wrote: > On Tue, Apr 16, 2019 at 11:17 AM Liviu Dudau wrote: > > > > On Tue, Apr 16, 2019 at 09:34:20AM +0200, Daniel Vetter wrote: > > > On Mon, Apr 15, 2019 at 10:20:45AM +0100, Liviu Dudau wrote: > > > > On Mon, Apr 15, 2019 at 08:59:30AM +0100, james qian wang (Arm Technology China) wrote: > > > > > On Fri, Apr 12, 2019 at 02:08:28PM +0000, Ben Davis wrote: > > > > > > Add new properties to specify width and height for writeback. > > > > > > > > > > > > Signed-off-by: Ben Davis > > > > > > --- > > > > > > drivers/gpu/drm/drm_atomic_uapi.c | 8 ++++++++ > > > > > > drivers/gpu/drm/drm_writeback.c | 28 ++++++++++++++++++++++++++++ > > > > > > include/drm/drm_connector.h | 4 ++++ > > > > > > include/drm/drm_mode_config.h | 10 ++++++++++ > > > > > > 4 files changed, 50 insertions(+) > > > > > > > > > > > > -- > > > > > > 2.7.4 > > > > > > > > > > > > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c > > > > > > index d520a04..1f68dce 100644 > > > > > > --- a/drivers/gpu/drm/drm_atomic_uapi.c > > > > > > +++ b/drivers/gpu/drm/drm_atomic_uapi.c > > > > > > @@ -765,6 +765,10 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector, > > > > > > return -EINVAL; > > > > > > } > > > > > > state->content_protection = val; > > > > > > + } else if (property == config->prop_writeback_w) { > > > > > > + state->writeback_w = val; > > > > > > + } else if (property == config->prop_writeback_h) { > > > > > > + state->writeback_h = val; > > > > > > } else if (property == config->writeback_fb_id_property) { > > > > > > struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, NULL, val); > > > > > > int ret = drm_atomic_set_writeback_fb_for_connector(state, fb); > > > > > > @@ -837,6 +841,10 @@ drm_atomic_connector_get_property(struct drm_connector *connector, > > > > > > *val = state->scaling_mode; > > > > > > } else if (property == connector->content_protection_property) { > > > > > > *val = state->content_protection; > > > > > > + } else if (property == config->prop_writeback_w) { > > > > > > + *val = state->writeback_w; > > > > > > + } else if (property == config->prop_writeback_h) { > > > > > > + *val = state->writeback_h; > > > > > > } else if (property == config->writeback_fb_id_property) { > > > > > > /* Writeback framebuffer is one-shot, write and forget */ > > > > > > *val = 0; > > > > > > diff --git a/drivers/gpu/drm/drm_writeback.c b/drivers/gpu/drm/drm_writeback.c > > > > > > index c20e6fe..3d0453e 100644 > > > > > > --- a/drivers/gpu/drm/drm_writeback.c > > > > > > +++ b/drivers/gpu/drm/drm_writeback.c > > > > > > @@ -74,6 +74,12 @@ > > > > > > * applications making use of writeback connectors *always* retrieve an > > > > > > * out-fence for the commit and use it appropriately. > > > > > > * From userspace, this property will always read as zero. > > > > > > + * > > > > > > + * "WRITEBACK_W": > > > > > > + * The width of the writeback buffer to write back. 0 acts as default. > > > > > > + * > > > > > > + * "WRITEBACK_H": > > > > > > + * The height of the writeback buffer to write back. 0 acts as default. > > > > > > */ > > > > > > > > > > > > #define fence_to_wb_connector(x) container_of(x->lock, \ > > > > > > @@ -141,6 +147,22 @@ static int create_writeback_properties(struct drm_device *dev) > > > > > > dev->mode_config.writeback_out_fence_ptr_property = prop; > > > > > > } > > > > > > > > > > > > + if (!dev->mode_config.prop_writeback_w) { > > > > > > + prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC, > > > > > > + "WRITEBACK_W", 1, UINT_MAX); > > > > > > + if (!prop) > > > > > > + return -ENOMEM; > > > > > > + dev->mode_config.prop_writeback_w = prop; > > > > > > + } > > > > > > + > > > > > > + if (!dev->mode_config.prop_writeback_h) { > > > > > > + prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC, > > > > > > + "WRITEBACK_H", 1, UINT_MAX); > > > > > > + if (!prop) > > > > > > + return -ENOMEM; > > > > > > + dev->mode_config.prop_writeback_h = prop; > > > > > > + } > > > > > > + > > > > > > return 0; > > > > > > } > > > > > > > > > > > > @@ -225,6 +247,12 @@ int drm_writeback_connector_init(struct drm_device *dev, > > > > > > drm_object_attach_property(&connector->base, > > > > > > config->writeback_pixel_formats_property, > > > > > > blob->base.id); > > > > > > + > > > > > > + drm_object_attach_property(&connector->base, > > > > > > + config->prop_writeback_w, 0); > > > > > > + drm_object_attach_property(&connector->base, > > > > > > + config->prop_writeback_h, 0); > > > > > > > > > > Hi Ben: > > > > > Do we real need these two individual properties for specifing the writeback > > > > > w/h, can we use fb->w/h ? > > > > > And since these two properties are added as common and standard properties, > > > > > it influnce all existing write-back implementation which all assumed > > > > > writeback size as fb->w/h. > > > > > > > > The idea of having these additional properties was to maintain backwards > > > > compatibility (of some sort). If you don't set writeback_w/h then the > > > > assumption is that they are the same as fb->w/h, but I can see how it's > > > > going to be confusing to have fb->w/h different from crtc->w/h and > > > > different from writeback_w/h. > > > > > > Since we already have crtc_w/h independent of writeback_fb_w/h, do we need > > > another set of w/h? Are all the interactions between these tree > > > well-defined? > > > > No, we probably don't need another set of w/h values. As for the > > interaction, I propose the following: > > > > - writeback is only attached to a connector, so the crtc_x/y/w/h are the > > "input source" parameters into the writeback. Given that we put in the > > writeback the content of the CRTC, I suggest we ignore x,y (consider > > them to be always 0 for the writeback output). > > There's no crtc_x/y. Bah, sorry about that! > And what I meant with crtc_w/h is > crtc_state->mode->h/vdisplay. And you can already express scaling with > that, by setting the plane_state->crtc_x/y/h/w parameters as you wish. We don't have a plane associated with the writeback, it's a connector with a framebuffer attached to it. :( > > > - writeback has a framebuffer attached, so we can use the fb->w/h to > > determine if we need to do any scaling of the output. > > Hm, not sure we want that. You might want to automatically round > fb->w/h to whatever (ok right now we don't do that I think anywhere), > so forcing the output to match the fb->h/w doesn't make sense for me. > It's also inconsistent with how we treat fb attached to planes (where > we have the full set of src coordinates). The writeback will have to fit into that framebuffer, so it can't be bigger than fb->w/h. Smaller, yes. > > > > Atm I'm assuming that writeback is using crtc_w/h into the fb, at offset > > > 0, not scaled any further. But the planes themselves can be scaled into > > > the crtc_w/h window ofc. > > > > Our hardware has the ability to also write back one of the planes and > > scale it during writeback, but we have no way of expressing that in DRM > > via connectors, so we are going to ignore that case. The supported usecase > > is for the planes to be scaled into the "composition" area which is the size > > of the CRTC, and then writeback that to memory, possibly with scaling (we > > officially only going to support downscaling due to external dependencies > > on the memory clock that is needed for supporting upscaling). > > Hm, see above, you can already express that: > - set crtc_state->mode->h/vdisplay to what you want the resulting > writeback image to be sized at. > - place the plane however you want using the plane properties within > that crtc window. The way we agreed ~2 years ago in the community to implement this was to have the writeback as a connector that gets the "output" of the CRTC and writes it into memory rather than on phosphorus. We have not added a plane to that, but in hindsight we might find it would have been useful. Best regards, Liviu > > Cheers, Daniel > > > > > Liviu > > > > > > > > > > Iirc the hw supporting writeback thus far needs a dedicated crtc for > > > writeback, so adding yet another scaling window is not needed? > > > -Daniel > > > > > > > > To compatible with existing writeback support, I suggest to keep to > > > > > use fb->w/h or add these properties as malidp private. > > > > > > > > We don't need to make them malidp private, there is nothing malidp > > > > specific in them. I'll talk with Ben, we should probably drop this patch > > > > entirely and just enable malidp scaling when fb->w/h differ from > > > > crtc->w/h. > > > > > > > > Best regards, > > > > Liviu > > > > > > > > > > > > > > > > > > Thanks > > > > > James > > > > > > > > > > > > > > > > wb_connector->pixel_formats_blob_ptr = blob; > > > > > > > > > > > > return 0; > > > > > > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h > > > > > > index 8fe22ab..51c4cb2 100644 > > > > > > --- a/include/drm/drm_connector.h > > > > > > +++ b/include/drm/drm_connector.h > > > > > > @@ -515,6 +515,10 @@ struct drm_connector_state { > > > > > > */ > > > > > > struct drm_writeback_job *writeback_job; > > > > > > > > > > > > + /** @writeback_w: width of plane to write to wb buffer */ > > > > > > + /** @writeback_h: height of plane to write to wb buffer */ > > > > > > + uint32_t writeback_w, writeback_h; > > > > > > + > > > > > > /** > > > > > > * @max_requested_bpc: Connector property to limit the maximum bit > > > > > > * depth of the pixels. > > > > > > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h > > > > > > index 7f60e8e..a0c2133 100644 > > > > > > --- a/include/drm/drm_mode_config.h > > > > > > +++ b/include/drm/drm_mode_config.h > > > > > > @@ -622,6 +622,16 @@ struct drm_mode_config { > > > > > > */ > > > > > > struct drm_property *prop_crtc_h; > > > > > > /** > > > > > > + * @prop_writeback_w: Writeback connector property for the plane > > > > > > + * destination position in the writeback buffer. > > > > > > + */ > > > > > > + struct drm_property *prop_writeback_w; > > > > > > + /** > > > > > > + * @prop_writeback_h: Writeback connector property for the plane > > > > > > + * destination position in the writeback buffer. > > > > > > + */ > > > > > > + struct drm_property *prop_writeback_h; > > > > > > + /** > > > > > > * @prop_fb_id: Default atomic plane property to specify the > > > > > > * &drm_framebuffer. > > > > > > */ > > > > > > > > > > Pls del this window style line ending > > > > > > > > > > > > > -- > > > > ==================== > > > > | I would like to | > > > > | fix the world, | > > > > | but they're not | > > > > | giving me the | > > > > \ source code! / > > > > --------------- > > > > ¯\_(ツ)_/¯ > > > > _______________________________________________ > > > > dri-devel mailing list > > > > dri-devel@lists.freedesktop.org > > > > https://lists.freedesktop.org/mailman/listinfo/dri-devel > > > > > > -- > > > Daniel Vetter > > > Software Engineer, Intel Corporation > > > http://blog.ffwll.ch > > > > -- > > ==================== > > | I would like to | > > | fix the world, | > > | but they're not | > > | giving me the | > > \ source code! / > > --------------- > > ¯\_(ツ)_/¯ > > _______________________________________________ > > dri-devel mailing list > > dri-devel@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/dri-devel > > > > -- > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯