From nobody Sun Feb 8 17:04:30 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0ADF2EB64DA for ; Sat, 1 Jul 2023 02:09:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229893AbjGACJn (ORCPT ); Fri, 30 Jun 2023 22:09:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229601AbjGACJg (ORCPT ); Fri, 30 Jun 2023 22:09:36 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8D2484212 for ; Fri, 30 Jun 2023 19:09:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=lbvpM8EakHHy+USxQroX9eqPrbtC1pudfZEWMIGGBk8=; b=jAChnC3XqO7clZ/D2UTM1bk7V+ ACA7rfSqiHtTvJaIgmVDgk55VAkxAmI4Bd7QI32sJhjL308zVBz4J4IlNor6WNWW00oZLLbfGBSkX 6JRw0ro4uj+GBUCsCqs2QnCZ0Jvrq9aeuo96lkILj4+NSjsOfbGF201fbt0bZYA+sf/EOsxAv1+f/ 70ko7KOkjMmY9XOMJ/KXVTjWIdL84rd1IBnKsIZNAWqJvhUxrPh+wZY0PmVfNFp4Zes3hcRRny7dU 8abbZpMs1sj9rvGQYi/7XPm5PAMc95/orFVitWvHu7U8c2Ev3vIfFWyIEh2TcoldMRj28N38oUMgY ZDTUbvwg==; Received: from [187.74.70.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qFQ3G-006abr-R6; Sat, 01 Jul 2023 04:09:31 +0200 From: =?UTF-8?q?Andr=C3=A9=20Almeida?= To: dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, wayland-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, alexander.deucher@amd.com, christian.koenig@amd.com, pierre-eric.pelloux-prayer@amd.com, Simon Ser , Rob Clark , Pekka Paalanen , Daniel Vetter , Daniel Stone , =?UTF-8?q?=27Marek=20Ol=C5=A1=C3=A1k=27?= , Dave Airlie , =?UTF-8?q?Michel=20D=C3=A4nzer?= , Italo Nicola , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v4 1/6] drm: allow DRM_MODE_PAGE_FLIP_ASYNC for atomic commits Date: Fri, 30 Jun 2023 23:09:12 -0300 Message-ID: <20230701020917.143394-2-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230701020917.143394-1-andrealmeid@igalia.com> References: <20230701020917.143394-1-andrealmeid@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Simon Ser If the driver supports it, allow user-space to supply the DRM_MODE_PAGE_FLIP_ASYNC flag to request an async page-flip. Set drm_crtc_state.async_flip accordingly. Document that drivers will reject atomic commits if an async flip isn't possible. This allows user-space to fall back to something else. For instance, Xorg falls back to a blit. Another option is to wait as close to the next vblank as possible before performing the page-flip to reduce latency. Signed-off-by: Simon Ser Reviewed-by: Alex Deucher Co-developed-by: Andr=C3=A9 Almeida Signed-off-by: Andr=C3=A9 Almeida --- v4: no changes --- drivers/gpu/drm/drm_atomic_uapi.c | 28 +++++++++++++++++++++++++--- include/uapi/drm/drm_mode.h | 9 +++++++++ 2 files changed, 34 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic= _uapi.c index d867e7f9f2cd..dfd4cf7169df 100644 --- a/drivers/gpu/drm/drm_atomic_uapi.c +++ b/drivers/gpu/drm/drm_atomic_uapi.c @@ -1286,6 +1286,18 @@ static void complete_signaling(struct drm_device *de= v, kfree(fence_state); } =20 +static void +set_async_flip(struct drm_atomic_state *state) +{ + struct drm_crtc *crtc; + struct drm_crtc_state *crtc_state; + int i; + + for_each_new_crtc_in_state(state, crtc, crtc_state, i) { + crtc_state->async_flip =3D true; + } +} + int drm_mode_atomic_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { @@ -1326,9 +1338,16 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, } =20 if (arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) { - drm_dbg_atomic(dev, - "commit failed: invalid flag DRM_MODE_PAGE_FLIP_ASYNC\n"); - return -EINVAL; + if (!dev->mode_config.async_page_flip) { + drm_dbg_atomic(dev, + "commit failed: DRM_MODE_PAGE_FLIP_ASYNC not supported\n"); + return -EINVAL; + } + if (dev->mode_config.atomic_async_page_flip_not_supported) { + drm_dbg_atomic(dev, + "commit failed: DRM_MODE_PAGE_FLIP_ASYNC not supported with ato= mic\n"); + return -EINVAL; + } } =20 /* can't test and expect an event at the same time. */ @@ -1426,6 +1445,9 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, if (ret) goto out; =20 + if (arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) + set_async_flip(state); + if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) { ret =3D drm_atomic_check_only(state); } else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) { diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index 46becedf5b2f..56342ba2c11a 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -949,6 +949,15 @@ struct hdr_output_metadata { * Request that the page-flip is performed as soon as possible, ie. with no * delay due to waiting for vblank. This may cause tearing to be visible on * the screen. + * + * When used with atomic uAPI, the driver will return an error if the hard= ware + * doesn't support performing an asynchronous page-flip for this update. + * User-space should handle this, e.g. by falling back to a regular page-f= lip. + * + * Note, some hardware might need to perform one last synchronous page-flip + * before being able to switch to asynchronous page-flips. As an exception, + * the driver will return success even though that first page-flip is not + * asynchronous. */ #define DRM_MODE_PAGE_FLIP_ASYNC 0x02 #define DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE 0x4 --=20 2.41.0 From nobody Sun Feb 8 17:04:30 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8731CC001B0 for ; Sat, 1 Jul 2023 02:09:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229940AbjGACJq (ORCPT ); Fri, 30 Jun 2023 22:09:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229878AbjGACJj (ORCPT ); Fri, 30 Jun 2023 22:09:39 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BC9A1997 for ; Fri, 30 Jun 2023 19:09:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=HPO0XUJvL8MHQ9quXzm+tMdaWyxXHw4tFqRhJIQaDP4=; b=G81G6jtzf5peArDdZPEHo5CFND 9ShevZnQGMgqjIxJa8fJvELfg5qHbJpntuyUtQyljiOgRr00DsNj0pIb9i7kfq5Ar6aFMWsZrpD05 AwlRe/nsLRKLaDUtiEMgPPijGxLzDmpTs/WOpKeUWfXJ65CONWQFUhwxoQQfM2XqO4xLqFb1tux1P oraLfPnC4/2W3gEwfeZSCfxviWGgka8EUWyjkuo5AkzrVG/W4gxVDTaQwBGpUuDn4SZgEcGJ9VCtK 6SMHc7OWFITQUT6bOwQsXMdoYP+c7qg4hoL0Gd8nh6kmYLY/HssVVGJ1uNzftRxSm3Te6PkhEYILP XcKuM40A==; Received: from [187.74.70.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qFQ3L-006abr-S9; Sat, 01 Jul 2023 04:09:36 +0200 From: =?UTF-8?q?Andr=C3=A9=20Almeida?= To: dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, wayland-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, alexander.deucher@amd.com, christian.koenig@amd.com, pierre-eric.pelloux-prayer@amd.com, Simon Ser , Rob Clark , Pekka Paalanen , Daniel Vetter , Daniel Stone , =?UTF-8?q?=27Marek=20Ol=C5=A1=C3=A1k=27?= , Dave Airlie , =?UTF-8?q?Michel=20D=C3=A4nzer?= , Italo Nicola , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v4 2/6] drm: introduce DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP Date: Fri, 30 Jun 2023 23:09:13 -0300 Message-ID: <20230701020917.143394-3-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230701020917.143394-1-andrealmeid@igalia.com> References: <20230701020917.143394-1-andrealmeid@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Simon Ser This new kernel capability indicates whether async page-flips are supported via the atomic uAPI. DRM clients can use it to check for support before feeding DRM_MODE_PAGE_FLIP_ASYNC to the kernel. Make it clear that DRM_CAP_ASYNC_PAGE_FLIP is for legacy uAPI only. Signed-off-by: Simon Ser Reviewed-by: Andr=C3=A9 Almeida Reviewed-by: Alex Deucher Signed-off-by: Andr=C3=A9 Almeida --- v4: no changes --- drivers/gpu/drm/drm_ioctl.c | 5 +++++ include/uapi/drm/drm.h | 10 +++++++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 7c9d66ee917d..8f756b99260d 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -302,6 +302,11 @@ static int drm_getcap(struct drm_device *dev, void *da= ta, struct drm_file *file_ case DRM_CAP_CRTC_IN_VBLANK_EVENT: req->value =3D 1; break; + case DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP: + req->value =3D drm_core_check_feature(dev, DRIVER_ATOMIC) && + dev->mode_config.async_page_flip && + !dev->mode_config.atomic_async_page_flip_not_supported; + break; default: return -EINVAL; } diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index a87bbbbca2d4..54c558f81f3c 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -706,7 +706,8 @@ struct drm_gem_open { /** * DRM_CAP_ASYNC_PAGE_FLIP * - * If set to 1, the driver supports &DRM_MODE_PAGE_FLIP_ASYNC. + * If set to 1, the driver supports &DRM_MODE_PAGE_FLIP_ASYNC for legacy + * page-flips. */ #define DRM_CAP_ASYNC_PAGE_FLIP 0x7 /** @@ -767,6 +768,13 @@ struct drm_gem_open { * Documentation/gpu/drm-mm.rst, section "DRM Sync Objects". */ #define DRM_CAP_SYNCOBJ_TIMELINE 0x14 +/** + * DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP + * + * If set to 1, the driver supports &DRM_MODE_PAGE_FLIP_ASYNC for atomic + * commits. + */ +#define DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP 0x15 =20 /* DRM_IOCTL_GET_CAP ioctl argument type */ struct drm_get_cap { --=20 2.41.0 From nobody Sun Feb 8 17:04:30 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FEF3EB64DD for ; Sat, 1 Jul 2023 02:10:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230008AbjGACKF (ORCPT ); Fri, 30 Jun 2023 22:10:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229897AbjGACJo (ORCPT ); Fri, 30 Jun 2023 22:09:44 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B02044213 for ; Fri, 30 Jun 2023 19:09:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=mFfau7nIYSTNFQZxA6ftp9PAp8q78Z2XWdM3YuMBn/Y=; b=sWwtOONIdKqA2mMlLCJC9q3u9Q WjIprRAukvaepVXv8Zd5uOgCTHjQMlCL3yE0abI16AZQjYwE1kcMK5Spk9F5z8/23DqYFMd7/fNj2 8561BsyNioG1N38YmO0UZJ9hnq9RoRm5xTihkAuNenIkkJhn2V99X2KAl+/tBGIGCAfPiPvT1GaeA rFZvkD//Syk+zAWvcZhTikEmkwlsMY9zK1O9CXRrYzwmCWl7XF0l4gUICAA2FxeAbb3LtkJvqVgAU xFGKYd5wwK+IISQXF643jtzPdhze3V6B+JQCGQPhQpn/tCPIKTkaNVdt79GuxQvOJqN9rHaGuxIpC t1VblfLQ==; Received: from [187.74.70.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qFQ3Q-006abr-TO; Sat, 01 Jul 2023 04:09:41 +0200 From: =?UTF-8?q?Andr=C3=A9=20Almeida?= To: dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, wayland-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, alexander.deucher@amd.com, christian.koenig@amd.com, pierre-eric.pelloux-prayer@amd.com, Simon Ser , Rob Clark , Pekka Paalanen , Daniel Vetter , Daniel Stone , =?UTF-8?q?=27Marek=20Ol=C5=A1=C3=A1k=27?= , Dave Airlie , =?UTF-8?q?Michel=20D=C3=A4nzer?= , Italo Nicola , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v4 3/6] drm: introduce drm_mode_config.atomic_async_page_flip_not_supported Date: Fri, 30 Jun 2023 23:09:14 -0300 Message-ID: <20230701020917.143394-4-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230701020917.143394-1-andrealmeid@igalia.com> References: <20230701020917.143394-1-andrealmeid@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Simon Ser This new field indicates whether the driver has the necessary logic to support async page-flips via the atomic uAPI. This is leveraged by the next commit to allow user-space to use this functionality. All atomic drivers setting drm_mode_config.async_page_flip are updated to also set drm_mode_config.atomic_async_page_flip_not_supported. We will gradually check and update these drivers to properly handle drm_crtc_state.async_flip in their atomic logic. The goal of this negative flag is the same as fb_modifiers_not_supported: we want to eventually get rid of all drivers missing atomic support for async flips. New drivers should not set this flag, instead they should support atomic async flips (if they support async flips at all). IOW, we don't want more drivers with async flip support for legacy but not atomic. Signed-off-by: Simon Ser Reviewed-by: Andr=C3=A9 Almeida Reviewed-by: Alex Deucher Signed-off-by: Andr=C3=A9 Almeida --- v4: no changes --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 1 + drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 1 + drivers/gpu/drm/i915/display/intel_display.c | 1 + drivers/gpu/drm/nouveau/nouveau_display.c | 1 + include/drm/drm_mode_config.h | 11 +++++++++++ 5 files changed, 15 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gp= u/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 7acd73e5004f..258461826140 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -3970,6 +3970,7 @@ static int amdgpu_dm_mode_config_init(struct amdgpu_d= evice *adev) adev_to_drm(adev)->mode_config.prefer_shadow =3D 1; /* indicates support for immediate flip */ adev_to_drm(adev)->mode_config.async_page_flip =3D true; + adev_to_drm(adev)->mode_config.atomic_async_page_flip_not_supported =3D t= rue; =20 state =3D kzalloc(sizeof(*state), GFP_KERNEL); if (!state) diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm= /atmel-hlcdc/atmel_hlcdc_dc.c index 29603561d501..8afb22b1e730 100644 --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c @@ -639,6 +639,7 @@ static int atmel_hlcdc_dc_modeset_init(struct drm_devic= e *dev) dev->mode_config.max_height =3D dc->desc->max_height; dev->mode_config.funcs =3D &mode_config_funcs; dev->mode_config.async_page_flip =3D true; + dev->mode_config.atomic_async_page_flip_not_supported =3D true; =20 return 0; } diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm= /i915/display/intel_display.c index 0aae9a1eb3d5..a5c503ca9168 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -8318,6 +8318,7 @@ static void intel_mode_config_init(struct drm_i915_pr= ivate *i915) mode_config->helper_private =3D &intel_mode_config_funcs; =20 mode_config->async_page_flip =3D HAS_ASYNC_FLIPS(i915); + mode_config->atomic_async_page_flip_not_supported =3D true; =20 /* * Maximum framebuffer dimensions, chosen to match diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/no= uveau/nouveau_display.c index ec3ffff487fc..f497dcd9e22f 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.c +++ b/drivers/gpu/drm/nouveau/nouveau_display.c @@ -709,6 +709,7 @@ nouveau_display_create(struct drm_device *dev) dev->mode_config.async_page_flip =3D false; else dev->mode_config.async_page_flip =3D true; + dev->mode_config.atomic_async_page_flip_not_supported =3D true; =20 drm_kms_helper_poll_init(dev); drm_kms_helper_poll_disable(dev); diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index 973119a9176b..47b005671e6a 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -918,6 +918,17 @@ struct drm_mode_config { */ bool async_page_flip; =20 + /** + * @atomic_async_page_flip_not_supported: + * + * If true, the driver does not support async page-flips with the + * atomic uAPI. This is only used by old drivers which haven't yet + * accomodated for &drm_crtc_state.async_flip in their atomic logic, + * even if they have &drm_mode_config.async_page_flip set to true. + * New drivers shall not set this flag. + */ + bool atomic_async_page_flip_not_supported; + /** * @fb_modifiers_not_supported: * --=20 2.41.0 From nobody Sun Feb 8 17:04:30 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 733AFEB64DC for ; Sat, 1 Jul 2023 02:10:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230038AbjGACKB (ORCPT ); Fri, 30 Jun 2023 22:10:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230008AbjGACJx (ORCPT ); Fri, 30 Jun 2023 22:09:53 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA5334481 for ; Fri, 30 Jun 2023 19:09:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=aypGJ9zKriwl5rC/G/jg2t+UqZhEdGjhBXoWEgZUCvg=; b=pRlncQxZeXRzBd8d9pNtQjHbw2 OLM2JC1G2JQw2KDsTdhL/GLf61rRrwZKZLPt1eoBrhgaWy0buejKE5scLhE+J5rDDdrCTXr/m1Tip C15kxHnHoG2WDisBaaxszxaFbhZKKddOhZ04VPevK1TxHJdoDWfvqbLaqib+QElLSris1ivEWygF8 bwcMpjoxkfkqbyj1EbP2BLw13IUxTJF5GTvIl8NlIbv61oJwvV0XQaL69UQ9Y+jhYsqr1oc5JDWGU hADgZkZ28NFCHyF0/7OsOGnXmDUQp+Jsd1d6NfZCqu2MZOHu+dO4SMMc7VhOuzKU7TwLfZ7PFY5yR nbC0vvUg==; Received: from [187.74.70.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qFQ3V-006abr-U9; Sat, 01 Jul 2023 04:09:46 +0200 From: =?UTF-8?q?Andr=C3=A9=20Almeida?= To: dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, wayland-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, alexander.deucher@amd.com, christian.koenig@amd.com, pierre-eric.pelloux-prayer@amd.com, Simon Ser , Rob Clark , Pekka Paalanen , Daniel Vetter , Daniel Stone , =?UTF-8?q?=27Marek=20Ol=C5=A1=C3=A1k=27?= , Dave Airlie , =?UTF-8?q?Michel=20D=C3=A4nzer?= , Italo Nicola , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v4 4/6] amd/display: indicate support for atomic async page-flips on DC Date: Fri, 30 Jun 2023 23:09:15 -0300 Message-ID: <20230701020917.143394-5-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230701020917.143394-1-andrealmeid@igalia.com> References: <20230701020917.143394-1-andrealmeid@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Simon Ser amdgpu_dm_commit_planes() already sets the flip_immediate flag for async page-flips. This flag is used to set the UNP_FLIP_CONTROL register. Thus, no additional change is required to handle async page-flips with the atomic uAPI. Signed-off-by: Simon Ser Reviewed-by: Andr=C3=A9 Almeida Reviewed-by: Alex Deucher Signed-off-by: Andr=C3=A9 Almeida --- v4: no changes --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gp= u/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 258461826140..7acd73e5004f 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -3970,7 +3970,6 @@ static int amdgpu_dm_mode_config_init(struct amdgpu_d= evice *adev) adev_to_drm(adev)->mode_config.prefer_shadow =3D 1; /* indicates support for immediate flip */ adev_to_drm(adev)->mode_config.async_page_flip =3D true; - adev_to_drm(adev)->mode_config.atomic_async_page_flip_not_supported =3D t= rue; =20 state =3D kzalloc(sizeof(*state), GFP_KERNEL); if (!state) --=20 2.41.0 From nobody Sun Feb 8 17:04:30 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F2EDEB64DC for ; Sat, 1 Jul 2023 02:10:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229961AbjGACKQ (ORCPT ); Fri, 30 Jun 2023 22:10:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230036AbjGACKB (ORCPT ); Fri, 30 Jun 2023 22:10:01 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E24144A9 for ; Fri, 30 Jun 2023 19:09:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=de0EjBF+hzGDM+i69O+/YEHpbFntjniyjiLFzME0BgQ=; b=a4riN7JozDAboAKaEv2mm+NGVe 0RWqF6NrsmtCsq+BgVwElu3CKKNrQqQTUuOwmFq4lmmENYMOQa+xFRRimUrdJ3Aqq5GiAwqZfKcPl cFxN0SMbhacM/QsGX8C7QNW7B24TQ9reYx+guJxGzvEfz0aUfFWcGNC0m8yv8iTJLsbHBSfPYaW89 yEYSMkoRROA8nDY+98yVgoZFlsCX25aF/E2tha5SYU8ZtPVq6QCc+QhyBs9SgNOMk/6RvGCDuhL/A 1l7R00AcEY5E5tecrzisQbMFDKNmC8Mj+jEttzk4yM4qowjC6pd/koLFamwWhufgGAwU7Qsm3K2g0 ItP8rF9Q==; Received: from [187.74.70.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qFQ3b-006abr-0e; Sat, 01 Jul 2023 04:09:51 +0200 From: =?UTF-8?q?Andr=C3=A9=20Almeida?= To: dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, wayland-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, alexander.deucher@amd.com, christian.koenig@amd.com, pierre-eric.pelloux-prayer@amd.com, Simon Ser , Rob Clark , Pekka Paalanen , Daniel Vetter , Daniel Stone , =?UTF-8?q?=27Marek=20Ol=C5=A1=C3=A1k=27?= , Dave Airlie , =?UTF-8?q?Michel=20D=C3=A4nzer?= , Italo Nicola , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v4 5/6] drm: Refuse to async flip with atomic prop changes Date: Fri, 30 Jun 2023 23:09:16 -0300 Message-ID: <20230701020917.143394-6-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230701020917.143394-1-andrealmeid@igalia.com> References: <20230701020917.143394-1-andrealmeid@igalia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Given that prop changes may lead to modesetting, which would defeat the fast path of the async flip, refuse any atomic prop change for async flips in atomic API. The only exceptions are the framebuffer ID to flip to and the mode ID, that could be referring to an identical mode. Signed-off-by: Andr=C3=A9 Almeida --- v4: new patch --- drivers/gpu/drm/drm_atomic_helper.c | 5 +++ drivers/gpu/drm/drm_atomic_uapi.c | 52 +++++++++++++++++++++++++++-- drivers/gpu/drm/drm_crtc_internal.h | 2 +- drivers/gpu/drm/drm_mode_object.c | 2 +- 4 files changed, 56 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atom= ic_helper.c index 2c2c9caf0be5..1e2973f0e1f6 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -629,6 +629,11 @@ drm_atomic_helper_check_modeset(struct drm_device *dev, WARN_ON(!drm_modeset_is_locked(&crtc->mutex)); =20 if (!drm_mode_equal(&old_crtc_state->mode, &new_crtc_state->mode)) { + if (new_crtc_state->async_flip) { + drm_dbg_atomic(dev, "[CRTC:%d:%s] no mode changes allowed during async= flip\n", + crtc->base.id, crtc->name); + return -EINVAL; + } drm_dbg_atomic(dev, "[CRTC:%d:%s] mode changed\n", crtc->base.id, crtc->name); new_crtc_state->mode_changed =3D true; diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic= _uapi.c index dfd4cf7169df..536c21f53b5f 100644 --- a/drivers/gpu/drm/drm_atomic_uapi.c +++ b/drivers/gpu/drm/drm_atomic_uapi.c @@ -972,13 +972,28 @@ int drm_atomic_connector_commit_dpms(struct drm_atomi= c_state *state, return ret; } =20 +static int drm_atomic_check_prop_changes(int ret, uint64_t old_val, uint64= _t prop_value, + struct drm_property *prop) +{ + if (ret !=3D 0 || old_val !=3D prop_value) { + drm_dbg_atomic(prop->dev, + "[PROP:%d:%s] No prop can be changed during async flip\n", + prop->base.id, prop->name); + return -EINVAL; + } + + return 0; +} + int drm_atomic_set_property(struct drm_atomic_state *state, struct drm_file *file_priv, struct drm_mode_object *obj, struct drm_property *prop, - uint64_t prop_value) + uint64_t prop_value, + bool async_flip) { struct drm_mode_object *ref; + uint64_t old_val; int ret; =20 if (!drm_property_change_valid_get(prop, prop_value, &ref)) @@ -995,6 +1010,13 @@ int drm_atomic_set_property(struct drm_atomic_state *= state, break; } =20 + if (async_flip) { + ret =3D drm_atomic_connector_get_property(connector, connector_state, + prop, &old_val); + ret =3D drm_atomic_check_prop_changes(ret, old_val, prop_value, prop); + break; + } + ret =3D drm_atomic_connector_set_property(connector, connector_state, file_priv, prop, prop_value); @@ -1003,6 +1025,7 @@ int drm_atomic_set_property(struct drm_atomic_state *= state, case DRM_MODE_OBJECT_CRTC: { struct drm_crtc *crtc =3D obj_to_crtc(obj); struct drm_crtc_state *crtc_state; + struct drm_mode_config *config =3D &crtc->dev->mode_config; =20 crtc_state =3D drm_atomic_get_crtc_state(state, crtc); if (IS_ERR(crtc_state)) { @@ -1010,6 +1033,18 @@ int drm_atomic_set_property(struct drm_atomic_state = *state, break; } =20 + /* + * We allow mode_id changes here for async flips, because we + * check later on drm_atomic_helper_check_modeset() callers if + * there are modeset changes or they are equal + */ + if (async_flip && prop !=3D config->prop_mode_id) { + ret =3D drm_atomic_crtc_get_property(crtc, crtc_state, + prop, &old_val); + ret =3D drm_atomic_check_prop_changes(ret, old_val, prop_value, prop); + break; + } + ret =3D drm_atomic_crtc_set_property(crtc, crtc_state, prop, prop_value); break; @@ -1017,6 +1052,7 @@ int drm_atomic_set_property(struct drm_atomic_state *= state, case DRM_MODE_OBJECT_PLANE: { struct drm_plane *plane =3D obj_to_plane(obj); struct drm_plane_state *plane_state; + struct drm_mode_config *config =3D &plane->dev->mode_config; =20 plane_state =3D drm_atomic_get_plane_state(state, plane); if (IS_ERR(plane_state)) { @@ -1024,6 +1060,13 @@ int drm_atomic_set_property(struct drm_atomic_state = *state, break; } =20 + if (async_flip && prop !=3D config->prop_fb_id) { + ret =3D drm_atomic_plane_get_property(plane, plane_state, + prop, &old_val); + ret =3D drm_atomic_check_prop_changes(ret, old_val, prop_value, prop); + break; + } + ret =3D drm_atomic_plane_set_property(plane, plane_state, file_priv, prop, prop_value); @@ -1312,6 +1355,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, struct drm_out_fence_state *fence_state; int ret =3D 0; unsigned int i, j, num_fences; + bool async_flip =3D false; =20 /* disallow for drivers not supporting atomic: */ if (!drm_core_check_feature(dev, DRIVER_ATOMIC)) @@ -1348,6 +1392,8 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, "commit failed: DRM_MODE_PAGE_FLIP_ASYNC not supported with ato= mic\n"); return -EINVAL; } + + async_flip =3D true; } =20 /* can't test and expect an event at the same time. */ @@ -1427,8 +1473,8 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, goto out; } =20 - ret =3D drm_atomic_set_property(state, file_priv, - obj, prop, prop_value); + ret =3D drm_atomic_set_property(state, file_priv, obj, + prop, prop_value, async_flip); if (ret) { drm_mode_object_put(obj); goto out; diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc= _internal.h index 501a10edd0e1..381130cebe81 100644 --- a/drivers/gpu/drm/drm_crtc_internal.h +++ b/drivers/gpu/drm/drm_crtc_internal.h @@ -251,7 +251,7 @@ int drm_atomic_set_property(struct drm_atomic_state *st= ate, struct drm_file *file_priv, struct drm_mode_object *obj, struct drm_property *prop, - uint64_t prop_value); + uint64_t prop_value, bool async_flip); int drm_atomic_get_property(struct drm_mode_object *obj, struct drm_property *property, uint64_t *val); =20 diff --git a/drivers/gpu/drm/drm_mode_object.c b/drivers/gpu/drm/drm_mode_o= bject.c index ba1608effc0f..64f519254895 100644 --- a/drivers/gpu/drm/drm_mode_object.c +++ b/drivers/gpu/drm/drm_mode_object.c @@ -536,7 +536,7 @@ static int set_property_atomic(struct drm_mode_object *= obj, obj_to_connector(obj), prop_value); } else { - ret =3D drm_atomic_set_property(state, file_priv, obj, prop, prop_value); + ret =3D drm_atomic_set_property(state, file_priv, obj, prop, prop_value,= false); if (ret) goto out; ret =3D drm_atomic_commit(state); --=20 2.41.0 From nobody Sun Feb 8 17:04:30 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6216EB64DC for ; Sat, 1 Jul 2023 02:10:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229897AbjGACKb (ORCPT ); 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charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Specify how the atomic state is maintained between userspace and kernel, plus the special case for async flips. Signed-off-by: Andr=C3=A9 Almeida --- v4: new patch --- Documentation/gpu/drm-uapi.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst index 65fb3036a580..5464376051cc 100644 --- a/Documentation/gpu/drm-uapi.rst +++ b/Documentation/gpu/drm-uapi.rst @@ -486,3 +486,22 @@ and the CRTC index is its position in this array. =20 .. kernel-doc:: include/uapi/drm/drm_mode.h :internal: + +KMS atomic state +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +If a userspace using the DRM atomic API would like to change the modeset, = it +needs to do in an atomic way, changing all desired properties in a single +commit. Following commits may contain the same properties again, as if the= y were +new. The kernel can then judge if those properties requires modesetting an= d real +changes, or it's just the same state as before. In summary, userspace comm= its do +not need to set the minimal state as possible and can commit redundant +information, and the kernel will ignore it. + +An observation must be made for atomic operations with DRM_MODE_PAGE_FLIP_= ASYNC. +In such scenarios properties values can be sent, but the if they change +something, the kernel will reject the flip. This is done because property +changes can lead to modesetting, that would defeat the goal of flipping as= fast +as possible. The only exceptions are the framebuffer ID to be flipped to a= nd +mode IDs changes, which could be referring to an identical mode, thus not +requiring modeset. --=20 2.41.0