From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 704BF1A6812 for ; Tue, 12 May 2026 15:38:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778600335; cv=none; b=niOgWZwrn5WiHFZQbpZEcWH/XqCAkXyDu/F2zviEY7wIWqxCW2kUJFcYIDc9HWYPtXzNhojk9KCP12T+HAlK5jIY5SaFIwFIRCxH3pfAi4O6cL1Hw6AmXyin8KrJq5b+EPkHpo+aNtloMrBdG3x+CPajv83Y8xAT8iJOUB9KwZM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778600335; c=relaxed/simple; bh=bTW8PIkNq6aZUF6NF1FmasGVCIC4HDNHJXMvlerQOQM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oFo5TGcY/zTEmJ6n3tQ1Y8QpUSxd28Us7XALA0jHlUeSd+HLhHoW1keUvmpeTeoBJGxPl50jto7hSAd6996wxIyrz538aYJTRBXE00ykrAYCBb7jyBGkRlvlK3Dh66An1ifLC3XHF7iazQd1lSF3zzGANpJ8S8pgpjhaehXr9rg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=gEdcW1qy; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="gEdcW1qy" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0603D1A25 for ; Tue, 12 May 2026 08:38:41 -0700 (PDT) Received: from [192.168.0.1] (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 011CB3F85F for ; Tue, 12 May 2026 08:38:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778600326; bh=bTW8PIkNq6aZUF6NF1FmasGVCIC4HDNHJXMvlerQOQM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gEdcW1qyzxuUCuyN7FmWlWt2wv8a89BJ+UxdL1u1e9Qzl8nVsWSUrfjITfM3YlYBt eAOJpOtYjNOxyZi/iZqVPRjTxQvpGgCmpQ2nnBG5hSx3Kt1xjg3jvxdMDUyRpnmOtS 92bu99ZlM2HZya7hG2jmI28aHHW6lHcd2f7ntZ4A= Date: Tue, 12 May 2026 16:38:18 +0100 From: Liviu Dudau To: Boris Brezillon Cc: Marcin =?utf-8?Q?=C5=9Alusarz?= , Ketil Johnsen , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Jonathan Corbet , Shuah Khan , Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , Christian =?utf-8?B?S8O2bmln?= , Steven Price , Daniel Almeida , Alice Ryhl , Matthias Brugger , AngeloGioacchino Del Regno , dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Florent Tomasin , nd@arm.com Subject: Re: [PATCH 4/8] drm/panthor: Add support for protected memory allocation in panthor Message-ID: References: <20260505140516.1372388-1-ketil.johnsen@arm.com> <20260505140516.1372388-5-ketil.johnsen@arm.com> <20260505181523.49a3d85c@fedora> <20260507135356.5428d50d@fedora> <20260512161111.0cb7000e@fedora> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260512161111.0cb7000e@fedora> On Tue, May 12, 2026 at 04:11:11PM +0200, Boris Brezillon wrote: > On Tue, 12 May 2026 14:47:27 +0100 > Liviu Dudau wrote: > > > On Thu, May 07, 2026 at 01:53:56PM +0200, Boris Brezillon wrote: > > > On Thu, 7 May 2026 11:02:26 +0200 > > > Marcin Ślusarz wrote: > > > > > > > On Tue, May 05, 2026 at 06:15:23PM +0200, Boris Brezillon wrote: > > > > > > @@ -277,9 +286,21 @@ int panthor_device_init(struct panthor_device *ptdev) > > > > > > return ret; > > > > > > } > > > > > > > > > > > > + /* If a protected heap name is specified but not found, defer the probe until created */ > > > > > > + if (protected_heap_name && strlen(protected_heap_name)) { > > > > > > > > > > Do we really need this strlen() > 0? Won't dma_heap_find() fail is the > > > > > name is "" already? > > > > > > > > If dma_heap_find() will fail, then the whole probe with fail too. > > > > This check prevents that. > > > > > > Yeah, that's also a questionable design choice. I mean, we can > > > currently probe and boot the FW even though we never setup the > > > protected FW sections, so why should we defer the probe here? Can't we > > > just retry the next time a group with the protected bit is created and > > > fail if we can find a protected heap? > > > > The problem we have with the current firmware is that it does a number of setup steps at "boot" > > time only. One of the steps is preparing its internal structures for when it enters protected > > mode and it stores them in the buffer passed in at firmware loading. We cannot later run the > > process when we have a group with protected mode set. > > No, but we can force a full/slow reset and have that thing > re-initialized, can't we? I mean, that's basically what we do when a > fast reset fails: we re-initialize all the sections and reset again, at > which point the FW should start from a fresh state, and be able to > properly initialize the protected-related stuff if protected sections > are populated. Am I missing something? Right, we can do that. For some reason I keep associating the reset with the error handling and not with "normal" operations. Best regards, Liviu -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯