From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.31]) (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 9DE5C1B956 for ; Wed, 17 Jan 2024 10:16:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=134.134.136.31 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705486584; cv=none; b=g1/pmJsw4fLYJEEueL41vqTpQYgJ1zxsJ54vYAfYm9wjeB0zTqfQsfgpxCb8Tn6WwdRIoZYs2UkiIaNcGfaoIbHkmiXa/ss7xBeoHiJE5TdA7sfoxRTrbPwtrh+JUTI8AXDNTTySANUDZ6fOHHFXwTRoLDdR+zHw7j+b/9Ezxok= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705486584; c=relaxed/simple; bh=x+koo6dAJ9hcyhU9Em/uUTNoV9nSRdJZ/CCvxgeGLrw=; h=DKIM-Signature:X-IronPort-AV:X-IronPort-AV:Received:X-ExtLoop1: X-IronPort-AV:X-IronPort-AV:Received:From:To:Cc:Subject: In-Reply-To:Organization:References:Date:Message-ID:MIME-Version: Content-Type; b=auyTG2xN/R1F6S067AaA7I72yhndDP8koEz1+LROjWW3vIckyRg3L7cE5PBwdtolKEzlJwxdDW5lEWHYmX1NKGLr6m9NGuLEX2WD9w0vJ3pbeMF97jox8Qz/95wMVOfbVnS25naD7kVFoSUQijFqWYs31SMX+qx/xekDz5M5VmI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=R7wBywrP; arc=none smtp.client-ip=134.134.136.31 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="R7wBywrP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1705486582; x=1737022582; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=x+koo6dAJ9hcyhU9Em/uUTNoV9nSRdJZ/CCvxgeGLrw=; b=R7wBywrPL9atlvoE2uV1lsrSJR9krhwE8//LkeBdA73SYasv8rqNu00P zqMWK6zmldBfrFjvUVYbolkJuc69vDnxo+M55C+FS2uwbVWpIMdlmrA0e NOy0Bn/8WR4b6jx3VlH42Be9nPDo0A8uGOS9//+iDTFP4U2o0cwS0aVAD STi1tquRQ2oXcgR3mi6gWCYx38Ug1ZkjjvHNnsmloeM6U94Tw1gm2aVk4 /EiAadpCP6TgAJ9Zv/I382czD86ZYglK/9x1LQEXLX6s+PK2H1fpnP5ec mCedfvefJ8ieUE2Me8uS+g1YDRIlPQluzIlPvveWwNBRziFBfsS84lmhG g==; X-IronPort-AV: E=McAfee;i="6600,9927,10955"; a="464412635" X-IronPort-AV: E=Sophos;i="6.05,200,1701158400"; d="scan'208";a="464412635" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jan 2024 02:16:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10955"; a="787756854" X-IronPort-AV: E=Sophos;i="6.05,200,1701158400"; d="scan'208";a="787756854" Received: from msznigir-mobl.ger.corp.intel.com (HELO localhost) ([10.252.38.230]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jan 2024 02:16:17 -0800 From: Jani Nikula To: Maxime Ripard , Jessica Zhang Cc: Neil Armstrong , Thomas Zimmermann , Sam Ravnborg , quic_abhinavk@quicinc.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Vetter , David Airlie Subject: Re: [PATCH RFC 0/4] Support for Simulated Panels In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20240116-jz-test-sim-panel-v1-0-f9511f46c9c7@quicinc.com> Date: Wed, 17 Jan 2024 12:16:14 +0200 Message-ID: <87cyu0qn81.fsf@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Wed, 17 Jan 2024, Maxime Ripard wrote: > Hi, > > On Tue, Jan 16, 2024 at 02:22:03PM -0800, Jessica Zhang wrote: >> This series introduces a simulated MIPI DSI panel. >> >> Currently, the only way to validate DSI connectors is with a physical >> panel. Since obtaining physical panels for all possible DSI configurations >> is logistically infeasible, introduce a way for DSI drivers to simulate a >> panel. >> >> This will be helpful in catching DSI misconfiguration bugs and catching >> performance issues for high FPS panels that might not be easily >> obtainable. >> >> For now, the simulated panel driver only supports setting customized >> modes via the panel_simlation.mode modparam. Eventually, we would like >> to add more customizations (such as configuring DSC, dual DSI, etc.). > > I think that it's more complicated than it needs to be. Both too complicated and not complicated enough! :p > Why do we need to support (and switch to) both the actual and > "simulated" panel? > > Wouldn't it be simpler if we had a vkms-like panel that we could either > configure from DT or from debugfs that would just be registered the > usual way and would be the only panel we register? I get the idea of trying to test DSI code without panels, and looking at the goals above, I think your vkms suggestion is going to fall short of those goals. However, my gut feeling is that creating a simulated panel to catch DSI misconfiguration etc. is going to be insanely complicated, and this series doesn't even scratch the surface. I guess my questions are, what's the scope here really, are those goals realistic, does more code already exist beyond this skeleton? BR, Jani. -- Jani Nikula, Intel