From nobody Wed Dec 17 23:56:41 2025 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 BF2F4C04A94 for ; Tue, 15 Aug 2023 18:59:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239573AbjHOS6c (ORCPT ); Tue, 15 Aug 2023 14:58:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59126 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239516AbjHOS56 (ORCPT ); Tue, 15 Aug 2023 14:57:58 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 808BA210A for ; Tue, 15 Aug 2023 11:57:35 -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=TVMdAoDdkx9jLjKJOYRYZPm8RW3qIM+jfzlkYz40wQ8=; b=QXaH3HsuFEQMcEH7GwbLvUlIeA jJ0j5AKmwUd1XurOLY6yuEvOSakJrm0CjrwJzb+64pKDrA+Sq+yXcubkzP32SMWUPWPjCSFkupSiy +3gHY3qRyZHPKbITVtk+FRM9d/PR9R9nkF197oA8cIOQ4BdMgTm0NKorAalH1RCtRpps78Ld629Cw Bq90dEtNKgWVPMW9RRZdQuOg1zasQ4WNOD88bxfOBJKpHb3378LaRRjeemWuADci/+CUUHw+oPvMH TG6l7tZgqdaavl3RdrwRJIpDskql9COE7Pfxi4sjT5fmN+LDnXPDLeEIBk/lbimFYB4AipO8fge3b JZ1jQpPQ==; Received: from [191.193.179.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qVzES-001Ca3-7o; Tue, 15 Aug 2023 20:57:32 +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?= , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v6 1/6] drm: allow DRM_MODE_PAGE_FLIP_ASYNC for atomic commits Date: Tue, 15 Aug 2023 15:57:05 -0300 Message-ID: <20230815185710.159779-2-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230815185710.159779-1-andrealmeid@igalia.com> References: <20230815185710.159779-1-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 --- v5: no changes 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 98d3b10c08ae..a15121e75a0a 100644 --- a/drivers/gpu/drm/drm_atomic_uapi.c +++ b/drivers/gpu/drm/drm_atomic_uapi.c @@ -1323,6 +1323,18 @@ 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) { @@ -1363,9 +1375,16 @@ 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. */ @@ -1468,6 +1487,9 @@ 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 ea1b639bcb28..04e6a3caa675 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -957,6 +957,15 @@ 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 Wed Dec 17 23:56:41 2025 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 386A1C04FE2 for ; Tue, 15 Aug 2023 18:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239590AbjHOS6i (ORCPT ); Tue, 15 Aug 2023 14:58:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239569AbjHOS6B (ORCPT ); Tue, 15 Aug 2023 14:58:01 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 313F2211C for ; Tue, 15 Aug 2023 11:57:40 -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=12D9YB4XL5iWqebcq+TLGzYuVPhU8QWpBYqiCegu2nk=; b=WghJqxe8TxHFnK1XYxxq+A7WLQ e62VanIPpX+mcWyG9UiL5FjfzQ4ltV8q/dVjqeNFd0IQf5r7gF1Oqe1vLSmzo3dNgrQMhVzolFTW3 5d8ap0btaEfqv/oQP6XJso9ueDHqOmWTD17IbtfLmQbym2ij+FBQ8Iq3n011Abylf9Z0tNq/IK3VP Ovp7m9CqI3yERWtwWUmeY4ohBkemIZS0gtg0+DVIxBGw7uMprLh+8ShSp776k9nsSvJkuD89uumZF 31T2YnWrWx23mz9VFa/SaZ49C0VMRY3i4yqJG3sAl8Gly8HcCorK++rGGH9HfIH8x5wkhAUydMjr9 JMEPCVnw==; Received: from [191.193.179.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qVzEX-001Ca3-7J; Tue, 15 Aug 2023 20:57:37 +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?= , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v6 2/6] drm: introduce DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP Date: Tue, 15 Aug 2023 15:57:06 -0300 Message-ID: <20230815185710.159779-3-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230815185710.159779-1-andrealmeid@igalia.com> References: <20230815185710.159779-1-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 --- v5: no changes 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 f03ffbacfe9b..3562b717b74f 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -301,6 +301,11 @@ 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 794c1d857677..58baefe32c23 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -713,7 +713,8 @@ 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 /** @@ -773,6 +774,13 @@ struct drm_gem_open { * :ref:`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 Wed Dec 17 23:56:41 2025 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 47189C07E8B for ; Tue, 15 Aug 2023 18:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239599AbjHOS6l (ORCPT ); Tue, 15 Aug 2023 14:58:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239581AbjHOS6C (ORCPT ); Tue, 15 Aug 2023 14:58:02 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E52C41FCF for ; Tue, 15 Aug 2023 11:57:44 -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=QXd4W2wFaxhhDN1Y2AZplTF5r+QGrQy4P17x4sfG4Dw=; b=p5TQt0RmbPuevG/OlV6kpggsgz kIjeZ3mAlB7e4dg5Ap4ojk+DMxCKFCDhHU3h4D9p9nWnGLlwRXZp2QwjGqXRQpe4WtO40bEIarwuR VjH3R9bRHehsfLq+8hq3qR1rHLqnU91hG/f0nG+WXimmsvGQ80NzP928HV9ZMIWEkvnE6VYzylqZo geMtGYQSCRAGa+2hQ6domzcCauVvq950GsVl7Y9Ehyx2xtMxLgfsAPQT+2Hx/6WvufR1wlMjqC6ij 7CeFXHftmO6wfwn3rd1r3t5sTecgpqAy6Lhf+BZ6PMb40QhxPfavX8wiu1byd3qIBbbYBkhOvawUM zerB2oBQ==; Received: from [191.193.179.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qVzEc-001Ca3-3s; Tue, 15 Aug 2023 20:57:42 +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?= , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v6 3/6] drm: introduce drm_mode_config.atomic_async_page_flip_not_supported Date: Tue, 15 Aug 2023 15:57:07 -0300 Message-ID: <20230815185710.159779-4-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230815185710.159779-1-andrealmeid@igalia.com> References: <20230815185710.159779-1-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 --- v5: no changes 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_driver.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 4d3d6009838c..4b433793f5a0 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -3924,6 +3924,7 @@ 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 fa0f9a93d50d..301b222c410d 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_driver.c b/drivers/= gpu/drm/i915/display/intel_display_driver.c index 8f144d4d3c39..f290c5c2e3c9 100644 --- a/drivers/gpu/drm/i915/display/intel_display_driver.c +++ b/drivers/gpu/drm/i915/display/intel_display_driver.c @@ -123,6 +123,7 @@ static void intel_mode_config_init(struct drm_i915_priv= ate *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 99977e5fe716..540895dabfc7 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.c +++ b/drivers/gpu/drm/nouveau/nouveau_display.c @@ -720,6 +720,7 @@ 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 Wed Dec 17 23:56:41 2025 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 562BEC07E8A for ; Tue, 15 Aug 2023 18:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239621AbjHOS6o (ORCPT ); Tue, 15 Aug 2023 14:58:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239587AbjHOS6C (ORCPT ); Tue, 15 Aug 2023 14:58:02 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 280801FD6 for ; Tue, 15 Aug 2023 11:57:50 -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=++dv1YcZtTUgwkcqesMhrWgRGVjCmLDErvcE127Lp4k=; b=MN1VQgdNk+1D8fu7wLlBepRrRB aCCVMsFhnQDaC+5HulasVarDOXq1JfDOKuKpdFvSxaieGhfGSLR8K7Dl0Cl4IOhuSvMWTA5K9c2kS meaXoweiHuatFmcmzMHvVAskQz00BoBt7zXwQcQyaT3YcuQOrtrIZh2qaB+7ju6BwgQBMD7yMDJ9Y kVIK0xCAslGPixRhDZNX6fChAX5uxj7GJWYzRYLgLUmFkH88FQUPwvIGLnz1TbHwiABezkfSZiC4e b/aOMJonS+x4zP+o50CiF+04939vh77T/li2buDWI97L5txZ5pIIb00SZgFr95ZZp9HtTDQ/9dsVp b1hpRKXw==; Received: from [191.193.179.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qVzEh-001Ca3-4Q; Tue, 15 Aug 2023 20:57:47 +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?= , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v6 4/6] amd/display: indicate support for atomic async page-flips on DC Date: Tue, 15 Aug 2023 15:57:08 -0300 Message-ID: <20230815185710.159779-5-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230815185710.159779-1-andrealmeid@igalia.com> References: <20230815185710.159779-1-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 --- v5: no changes 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 4b433793f5a0..4d3d6009838c 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -3924,7 +3924,6 @@ 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 Wed Dec 17 23:56:41 2025 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 65709C07E8D for ; Tue, 15 Aug 2023 18:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239656AbjHOS6q (ORCPT ); Tue, 15 Aug 2023 14:58:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239610AbjHOS6E (ORCPT ); Tue, 15 Aug 2023 14:58:04 -0400 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D8EDD1FEE for ; Tue, 15 Aug 2023 11:57:54 -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=CUu6cUqsLaQ5HGGvMpkPKfD424cCdPwZUqRPltbOhvo=; b=U1xAdWRfkC43Ht88i8qhNko242 V2BQ+owfjQg+NE7sV/18F4Rz3/PTgzevnf9FUiAGJdnG2dFy+1uc2Om2ODp+sRbNmwAZciN8J6vxc 6t+uThFwTrzR7LYZVcaR44p9HAPIqH/nvBDBElWg0GuoQSwlrRCfgxfWW1RpOAg/HDOQN98hWFwFp UaNZvyaiaR+Ow7Uggx2Q3KXQr1LSiz3JEA0XD3TS18dl0TSGQ+ZxkBvbt5iAKlX9bJCjKhYvJVivI uGODB3M2aj/5+/sIxTbKoD2wf17ZY3fWynol4ezf0LKXK8V/dcrUqMo2S3KI9ZDx8N0KwkqvlJgI8 0KPY6XhQ==; Received: from [191.193.179.209] (helo=steammachine.lan) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1qVzEm-001Ca3-59; Tue, 15 Aug 2023 20:57:52 +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?= , Randy Dunlap , hwentlan@amd.com, joshua@froggi.es, ville.syrjala@linux.intel.com, =?UTF-8?q?Andr=C3=A9=20Almeida?= Subject: [PATCH v6 5/6] drm: Refuse to async flip with atomic prop changes Date: Tue, 15 Aug 2023 15:57:09 -0300 Message-ID: <20230815185710.159779-6-andrealmeid@igalia.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230815185710.159779-1-andrealmeid@igalia.com> References: <20230815185710.159779-1-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 --- v5: no changes 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 292e38eb6218..b34e3104afd1 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 a15121e75a0a..6c423a7e8c7b 100644 --- a/drivers/gpu/drm/drm_atomic_uapi.c +++ b/drivers/gpu/drm/drm_atomic_uapi.c @@ -1006,13 +1006,28 @@ int drm_atomic_connector_commit_dpms(struct drm_ato= mic_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)) @@ -1029,6 +1044,13 @@ 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); @@ -1037,6 +1059,7 @@ 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)) { @@ -1044,6 +1067,18 @@ 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; @@ -1051,6 +1086,7 @@ 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)) { @@ -1058,6 +1094,13 @@ 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); @@ -1349,6 +1392,7 @@ 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)) @@ -1385,6 +1429,8 @@ 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. */ @@ -1469,8 +1515,8 @@ 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 ac0d2ce3f870..0e8355063eee 100644 --- a/drivers/gpu/drm/drm_mode_object.c +++ b/drivers/gpu/drm/drm_mode_object.c @@ -538,7 +538,7 @@ 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 Wed Dec 17 23:56:41 2025 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 82872C07E8E for ; Tue, 15 Aug 2023 18:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239707AbjHOS6t (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 From: Pekka Paalanen Specify how the atomic state is maintained between userspace and kernel, plus the special case for async flips. Signed-off-by: Pekka Paalanen Signed-off-by: Andr=C3=A9 Almeida --- v5: Add note that not every redundant attribute will result in no-op v4: total rework by Pekka --- Documentation/gpu/drm-uapi.rst | 44 ++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst index 65fb3036a580..b91ccaddeeb9 100644 --- a/Documentation/gpu/drm-uapi.rst +++ b/Documentation/gpu/drm-uapi.rst @@ -486,3 +486,47 @@ 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 + +An atomic commit can change multiple KMS properties in an atomic fashion, +without ever applying intermediate or partial state changes. Either the w= hole +commit succeeds or fails, and it will never be applied partially. This is = the +fundamental improvement of the atomic API over the older non-atomic API wh= ich is +referred to as the "legacy API". Applying intermediate state could unexpe= ctedly +fail, cause visible glitches, or delay reaching the final state. + +An atomic commit can be flagged with DRM_MODE_ATOMIC_TEST_ONLY, which mean= s the +complete state change is validated but not applied. Userspace should use = this +flag to validate any state change before asking to apply it. If validation= fails +for any reason, userspace should attempt to fall back to another, perhaps +simpler, final state. This allows userspace to probe for various configur= ations +without causing visible glitches on screen and without the need to undo a +probing change. + +The changes recorded in an atomic commit apply on top the current KMS stat= e in +the kernel. Hence, the complete new KMS state is the complete old KMS stat= e with +the committed property settings done on top. The kernel will try to avoid +no-operation changes, so it is safe for userspace to send redundant proper= ty +settings. However, not every situation allows for no-op changes, due to t= he +need to acquire locks for some attributes. Userspace needs to be aware tha= t some +redundant information might result in oversynchronization issues. No-oper= ation +changes do not count towards actually needed changes, e.g. setting MODE_I= D to a +different blob with identical contents as the current KMS state shall not = be a +modeset on its own. + +A "modeset" is a change in KMS state that might enable, disable, or tempor= arily +disrupt the emitted video signal, possibly causing visible glitches on scr= een. A +modeset may also take considerably more time to complete than other kinds = of +changes, and the video sink might also need time to adapt to the new signal +properties. Therefore a modeset must be explicitly allowed with the flag +DRM_MODE_ATOMIC_ALLOW_MODESET. This in combination with +DRM_MODE_ATOMIC_TEST_ONLY allows userspace to determine if a state change = is +likely to cause visible disruption on screen and avoid such changes when e= nd +users do not expect them. + +An atomic commit with the flag DRM_MODE_PAGE_FLIP_ASYNC is allowed to +effectively change only the FB_ID property on any planes. No-operation cha= nges +are ignored as always. Changing any other property will cause the commit t= o be +rejected. --=20 2.41.0