From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 531A517BB7 for ; Tue, 20 Aug 2024 14:27:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724164076; cv=none; b=qdDaf0D1ncbRvTkiz2piUShILEQOXZdwoi7RUhZb4yYL/hecIjVPXCeRIYNMkIuTJeDQ2kE4gq/+RBam5Xzpjioak7XtBT30lTbeY/l8nLTF2wSKC8sY/HwVU/SaKDS/FsjIT2s5exLy8BYlRacVM44Ly2kRRJLJSfYVjB03mFw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724164076; c=relaxed/simple; bh=ud7WgUdQsTU0o/iKSERG5jnLd+ZxS35DomwyHljjrU4=; h=From:To:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=iZAmfK93rSjqlTIHbHprkmRd0kBfQcsPYIZhf+Qgs08qb7mdCDa1G0fNgO6SpG080StQv3UckHBt0bdJwUFHwcZDW2IdolecCAG+0mM+U4VzTBF5D66jsyrhV+1pFcbP21Y5M7Y1SAjMP8uvB447zRzQk6FGbQl5W1ri593qibo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=FFbTZ6+z; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FFbTZ6+z" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1724164073; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Ubk8Yb33ek9o28qQ4n8Su7NGdGoK0OIgkJPolUgXNBk=; b=FFbTZ6+zMiUwhUi6n/9fKLngWjFSUA2yel3XrnfKt67/sme9oh3UAk75Wekvq+vYE0ss2E 8dxMsR8oM/bkWl6QlusHqpF5uLCPI2OU7kw09FmKMeEVN+RRK+bR89KHzrNDyA6xrHLnW0 Rs6JGzbDepc7k8TcWQj+Ofxxa34YRIs= Received: from mail-pj1-f70.google.com (mail-pj1-f70.google.com [209.85.216.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-442-I8zcGTNdPUG73dtaqe2EqA-1; Tue, 20 Aug 2024 10:27:50 -0400 X-MC-Unique: I8zcGTNdPUG73dtaqe2EqA-1 Received: by mail-pj1-f70.google.com with SMTP id 98e67ed59e1d1-2d3c6b19444so5289221a91.2 for ; Tue, 20 Aug 2024 07:27:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724164070; x=1724768870; h=content-transfer-encoding:mime-version:message-id:date:references :in-reply-to:subject:to:from:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=x3ovf2iShaZ9qbPPkoSbbQpKOfxaHuRmMXoaahs1Ka0=; b=v1TpwmEabLqk4AlGegn9rVi7fXfQapVFK4ys51VhbQXmxw1Zu2zYTXJSbZPork+PUs /Zi9xKEFbsi+TOAeIzptXgUsQPdmMI71JVrGPqRAhhM4PMw91vCSFqKxfFYw0TWR0weJ 88UjevohVorQ4o0Y4h2VRdGHUHHQQwlJO5C9cZhIER9BbFXbXu7cxXdpqRg+0RFO9WAp v9H4AsJY9UlC0FDQFdh738zQAJbqhgmXogyha4UYOVHzYaZeGd02gUUYm81RBjQrKaLn pNs/9M9afE5+TfXTIcuwgbxYyEzHiT305fHPpf5Or2AXy/lNW6IFKo4EOy78XhhyZBcM Yvag== X-Forwarded-Encrypted: i=1; AJvYcCWL8q7Gxm9Mhhz5/xsuXeAlRMy3EgYSrgPcOGi9EpROHXqSymKNXupy3eSA+zokka5F6+EKm832O5Z2VC3HYTsAWg/chO2GWSv0XPDDeW0= X-Gm-Message-State: AOJu0YzgEMNMkeMLPPngkhH+GfwZQ+Lo80Qcs4BUtrB8YIQaoGZ1JpfC 4mE/mw5eA9MPlN26SnKK9ttdURZ16aQUTQhyftOwn7xrnQqGdbOICfGmMumAPdg5suOvPVcvFxe k4k7xQWhNWCcTsKNta1b0i+uamscwdSJMkIUa8xog9vVV1UU+JdEw1qcBNB/8uPZ/ X-Received: by 2002:a17:90a:d50a:b0:2c9:69cc:3a6f with SMTP id 98e67ed59e1d1-2d3e00ebf73mr13052237a91.31.1724164069917; Tue, 20 Aug 2024 07:27:49 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHypeLeTNx3e7ttHvILw7VadgW74FuCGTQOH1UI/v7taOrjRzD7/mgP3FVnPfvZk5PmxOkWCA== X-Received: by 2002:a17:90a:d50a:b0:2c9:69cc:3a6f with SMTP id 98e67ed59e1d1-2d3e00ebf73mr13052205a91.31.1724164069457; Tue, 20 Aug 2024 07:27:49 -0700 (PDT) Received: from localhost ([181.120.144.238]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2d418e7b76csm6684852a91.2.2024.08.20.07.27.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 20 Aug 2024 07:27:49 -0700 (PDT) From: Javier Martinez Canillas To: Jocelyn Falempe , Thomas Zimmermann , David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Maarten Lankhorst , Maxime Ripard , Daniel Vetter , dri-devel@lists.freedesktop.org, virtualization@lists.linux.dev Subject: Re: [PATCH v2 2/2] drm/virtio: Fix host color format for big endian guests In-Reply-To: References: <20240820090908.151042-1-jfalempe@redhat.com> <20240820090908.151042-2-jfalempe@redhat.com> Date: Tue, 20 Aug 2024 16:27:46 +0200 Message-ID: <87a5h79sm5.fsf@minerva.mail-host-address-is-not-set> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Jocelyn Falempe writes: > On 20/08/2024 14:48, Thomas Zimmermann wrote: >> Hi >>=20 >> Am 20.08.24 um 11:07 schrieb Jocelyn Falempe: >>> The colors are inverted when testing a s390x VM on a s390x host. >>> Changing the conversion from DRM_FORMAT -> VIRTIO_GPU_FORMAT on big >>> endian guests fixes the colors. But it may break big-endian guest on >>> little-endian host. In this case, the fix should be in qemu, because >>> the host endianess is not known in the guest VM. >>> >>> Signed-off-by: Jocelyn Falempe >>> Acked-by: Javier Martinez Canillas >>> --- >>> =C2=A0 drivers/gpu/drm/virtio/virtgpu_plane.c | 12 ++++++++++-- >>> =C2=A0 1 file changed, 10 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c=20 >>> b/drivers/gpu/drm/virtio/virtgpu_plane.c >>> index 860b5757ec3fc..0ec6ecc96eb13 100644 >>> --- a/drivers/gpu/drm/virtio/virtgpu_plane.c >>> +++ b/drivers/gpu/drm/virtio/virtgpu_plane.c >>> @@ -37,16 +37,24 @@ static const uint32_t virtio_gpu_cursor_formats[] = =3D { >>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 DRM_FORMAT_ARGB8888, >>> =C2=A0 }; >>> +#ifdef __BIG_ENDIAN >>> +#define VIRTIO_GPU_HOST_XRGB8888 VIRTIO_GPU_FORMAT_X8R8G8B8_UNORM >>> +#define VIRTIO_GPU_HOST_ARGB8888 VIRTIO_GPU_FORMAT_A8R8G8B8_UNORM >>> +#else >>> +#define VIRTIO_GPU_HOST_XRGB8888 VIRTIO_GPU_FORMAT_B8G8R8X8_UNORM >>> +#define VIRTIO_GPU_HOST_ARGB8888 VIRTIO_GPU_FORMAT_B8G8R8A8_UNORM >>> +#endif >>=20 >> As these defines are only used here, would it be beneficial to put the= =20 >> __BIG_ENDIAN branch directly around the switch statement? > > That was my first version, but I found it difficult to read, when I mix= =20 > #ifdef in a switch case. > > > or maybe something like the following would be better ? > > > =09switch (drm_fourcc) { > #ifdef _BIG_ENDIAN > =09case DRM_FORMAT_XRGB8888: > =09=09format =3D VIRTIO_GPU_FORMAT_X8R8G8B8_UNORM; > =09=09break; > =09case DRM_FORMAT_ARGB8888: > =09=09format =3D VIRTIO_GPU_FORMAT_A8R8G8B8_UNORM; > =09=09break; > #else > =09case DRM_FORMAT_XRGB8888: > =09=09format =3D VIRTIO_GPU_FORMAT_B8G8R8X8_UNORM; > =09=09break; > =09case DRM_FORMAT_ARGB8888: > =09=09format =3D VIRTIO_GPU_FORMAT_B8G8R8A8_UNORM; > =09=09break; > #endif IMO your current patch is easier to read than having the ifdefery in the switch statement. --=20 Best regards, Javier Martinez Canillas Core Platforms Red Hat