From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 97531378830; Fri, 15 May 2026 08:03:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778832183; cv=none; b=F/qhL9rCa252Wace7xtLmgwWtdoHqnh5bJHtX0Cr5pyhw8K1QgsdysNqaC72SLA8XrRwiNTNg7gbD4dXS0AnXoYpuvXjoOd2zNho9sZCraByWWHJoJAmucFpoL3ypUezYmD7+QhHlZg/jpI19jv8LuTyhfZdiP9qCO82mYhuVQA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778832183; c=relaxed/simple; bh=BEKWtgaIVhEiq1VmEfN2oPMg1YJY/RV9AAVxvidyvKo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hPD3rezKtDQD7OiaB17L9sncWt2lrWOgu1EWXGu/UTm1lBhTUatvy5TfH/YBgIaCGw35XGYqVIryMZdJ0t+1BG0cUAR2LVyYV8dZ1TLNLUqquDtPESBn/hJkrRnJs3mtYqt9pKFUc1EYoMRuBJSmAoC9TH7sIpAFNXYwswxHBdM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=nYPHGW4U; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="nYPHGW4U" Received: from [192.168.88.20] (91-158-153-178.elisa-laajakaista.fi [91.158.153.178]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 06C7D63C; Fri, 15 May 2026 10:02:48 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1778832170; bh=BEKWtgaIVhEiq1VmEfN2oPMg1YJY/RV9AAVxvidyvKo=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=nYPHGW4UQIhJCre358b2q6pW4Zwj7YcqcngcihcTNnh+MGrNnKrkzPj08sfve3Fio YUOwX2G5twgcqYArSSenDzY9tXoiUUBw9xg6eCr0+lMiNo7LcbX8B0PqOicm0uvbrA tBSfJ74CcgMouz5xq3e9DWKRyZyIfyLIG124xo/E= Message-ID: <6db159d9-56af-4d79-a1f1-9d5a6349b5ac@ideasonboard.com> Date: Fri, 15 May 2026 11:02:55 +0300 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/5] drm/rcar-du: dsc: Add rudimentary Renesas R-Car V4H DSC driver To: Geert Uytterhoeven Cc: Michael Turquette , Stephen Boyd , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Magnus Damm , Marek Vasut , Laurent Pinchart , Kieran Bingham , Philipp Zabel , linux-renesas-soc@vger.kernel.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org References: <20260514-rcar-du-dsc-v1-0-d65f7a9e9841@ideasonboard.com> <20260514-rcar-du-dsc-v1-3-d65f7a9e9841@ideasonboard.com> From: Tomi Valkeinen Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Geert, On 15/05/2026 10:49, Geert Uytterhoeven wrote: > Hi Tomi, > > On Thu, 14 May 2026 at 14:25, Tomi Valkeinen > wrote: >> From: Marek Vasut >> >> The Renesas DSC Display Stream Compression is a bridge embedded in the >> Renesas R-Car V4H SoC. The bridge performs VESA DSC encoding of up to >> 8k or 400 Mpixel/s . Add rudimentary driver, which currently acts as a >> pass-through bridge and allows DSI1 to be operational on R-Car V4H. >> >> Signed-off-by: Marek Vasut >> [tomi.valkeinen: use bridge->next_bridge, minor changes] >> Signed-off-by: Tomi Valkeinen > > Thanks for your patch! > >> --- /dev/null >> +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_dsc.c > >> + >> +static void rcar_dsc_atomic_enable(struct drm_bridge *bridge, >> + struct drm_atomic_state *state) >> +{ >> + struct rcar_dsc *dsc = bridge_to_rcar_dsc(bridge); >> + >> + WARN_ON(clk_prepare_enable(dsc->clk)); Ah, just missed your comment and sent the v2. > Who don't you use pm_runtime_resume_and_get() instead, like > rcar_cmm.c? Then you don't need to get the clock at all, and the driver Hmm, why wouldn't I need to get the clock? What does the runtime PM do on Renesas? > will keep on working if the DSC ever ends up in a power domain. I can add runtime PM. I just felt that it was overcomplicating a "dummy" driver that just needs to enable the clock when the video pipeline is enabled. Tomi