From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender5-op-o11.zoho.com (sender5-op-o11.zoho.com [165.173.182.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8093437E5EE for ; Thu, 1 Oct 2026 10:46:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=165.173.182.11 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790851590; cv=pass; b=oWZslTvwd7QWYIolfOTAw+0HtLeul1paOP/aWj73buuiCGSZ81jwHvFqMxozWwWWK+fETrQb0yxMnnH4aAGW6nv3rcU1URgXzFhh3Y7cZpEvahp3y070BgQ04tfqxtia+6pVUs9Yi3BPm3zhyi938KFg7wteW5non8LHA+WZidw= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790851590; c=relaxed/simple; bh=xHheWCZqxhb77Fa7IJS/W05TvCOOUP/VZ4rMa+wK/Ts=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=SZ2uKUpbRRQsb+hloyIivT5XB7LFa/sZVgP0fLKOwa4IowR6syLUnBo7hq7Ef55iiVOKRrrL9FXb5f7ytcR+YNfCrhEq7UkVJOECIiS9NFxfLru1oVDrAWT5mvLLx6VTDQdqlHoF+0hXzkBi5cfWxeFecZMBtUni4AIFJvHlSjo= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b=F0U1KVhC; arc=pass smtp.client-ip=165.173.182.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b="F0U1KVhC" ARC-Seal: i=1; a=rsa-sha256; t=1790851578; cv=none; d=zohomail.com; s=zohoarc; b=h0X+2Z8FTOuZxR4NaFKUOo4BEeNPSS6M/zba4h8v827HnHaFgAJtCF7pVY44Oplvv9DuppvdAD49QoOJMFE6+9Ai/AkfJNF+9NasfyaSAqjmMIDYlxaZjltl6Vm2bCgTNNEVSYEMoDZzmpkxwjTGbGhu5R0SyT1/AOSGIcUnUMk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1790851578; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=2HzGCzDfJRSxURSFLUp5EFwzSKrik2fgPy8B4HnFxCE=; b=XQYX9XxneS9roREzfIftliV0HLRFMBp+0v1Atk+rOTmyUd9L8XUJErwQIQ1BfBDECU1oNW5lg2qDXLn7PjVk0iwoD2wZ2vVZKD6rT/2BPvMW90q4kSMil2XhGB6HTbAO4F+1vloqZWlnNu56Ruhqr46drJGBMofNYWM1tHLM95s= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=dmitry.osipenko@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1790851578; s=zohomail; d=collabora.com; i=dmitry.osipenko@collabora.com; h=Message-ID:Date:Date:MIME-Version:Subject:Subject:To:To:Cc:Cc:From:From:In-Reply-To:Content-Type:Content-Transfer-Encoding:Message-Id:Reply-To; bh=2HzGCzDfJRSxURSFLUp5EFwzSKrik2fgPy8B4HnFxCE=; b=F0U1KVhCyjzzZ7tGAijotnDY4dtGPmcI7HEANAqbpPKxp3V4LtsUeTO07XzJS1sk APFm7IHS2cV+LWZDn0RVzakRHfK+IfeXHPMk1q5fFQ9+CE2H3yzf3IKiKFbeuN6Tuow I9w+Gmr7rWCu30FS3BZzGEv3VtR+g1GIh6Bq3XXA= Received: by smtp.zohomail.com with SMTPS id 1790851576827524.4943374976424; Thu, 1 Oct 2026 03:46:16 -0700 (PDT) Message-ID: Date: Thu, 1 Oct 2026 13:46:11 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm/virtio: add ARGB8888 support for primary planes To: Thomas Zimmermann , Dorinda Bassey , dri-devel@lists.freedesktop.org, virtualization@lists.linux.dev Cc: kraxel@redhat.com, airlied@redhat.com, slp@redhat.com, mhrica@redhat.com, gurchetansingh@chromium.org, mripard@kernel.org, simona@ffwll.ch, linux-kernel@vger.kernel.org References: <20260930132707.500748-1-dbassey@redhat.com> <94f11a7e-7563-4480-8b00-6e3374865669@suse.de> Content-Language: en-US From: Dmitry Osipenko In-Reply-To: <94f11a7e-7563-4480-8b00-6e3374865669@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External On 9/30/26 18:03, Thomas Zimmermann wrote: > Hi > > Am 30.09.26 um 15:27 schrieb Dorinda Bassey: >> Add DRM_FORMAT_HOST_ARGB8888 to the list of supported formats for >> virtio-gpu primary planes. Without this, glmark2-drm fails at >> startup because it selects ARGB visual configs by default, which >> don't match the XRGB-only plane capabilities. This causes >> drmModeSetCrtc to fail with EINVAL. > > But does the host also support ARGB on the primary plane? We usually > don't export formats that are not available in (virtual) hardware. > > Best regards > Thomas > >> >> The virtio_gpu_translate_format() function already handles >> ARGB8888 translation to VIRTIO_GPU_FORMAT_B8G8R8A8_UNORM, >> so this just exposes the existing capability to userspace. >> >> Signed-off-by: Dorinda Bassey >> --- >>   drivers/gpu/drm/virtio/virtgpu_plane.c | 1 + >>   1 file changed, 1 insertion(+) For primary plane, alpha channel often doesn't matter as primary has fixed z=0 order and a usual alpha blending mode would account only overlay's alpha channel. Many real hw drivers expose alpha-channel formats for primary plane for compatibility with userspace, even though for them the alpha has no meaning for the primary plane. QEMU is most popular VMM using virtio-gpu, but there are others. For a stricter compatibility we can translate B8G8R8A8 to X8R8G8B8 for the primary plane in the driver code, but I assume in practice it's very unlike this will be necessary and we can always do it later on if will be needed. The change looks okay, will apply after testing. -- Best regards, Dmitry