From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-201.mailbox.org (mout-p-201.mailbox.org [80.241.56.171]) (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 0CFE935CB88; Thu, 12 Feb 2026 14:38:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770907130; cv=none; b=nDqbjNxtoG7WURT8+xhr3UFczSaPofFXh4DaryH04X1fsxV7/0DUUJ+aeqenvUHXTgdIr+FHZiccj717f46cfdfHD8dvAsAQgRe9cYDFo2SnpgqDbjPiCKjjDNPNBZGgujNbME4pszeay79Fa9cPnh+ZXlzyI0grKWHjdYUFMxs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770907130; c=relaxed/simple; bh=7gEtrTZqfCsga0dH/u2j1nxhfGCSN9L3pxdLBXwgRKc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=pgW4VJJd3C2nbbjtTNxFHNlNWr841eRiiEwEllIGcw3WfcW6k5G8h1KxAzRELqNyUYk+X2e+6nEN5MALaxGsJx/8ajTjAw/ZXl8niTkFU1iCJQfE4V7IpkvlhvAw2i4mOMLqABmGH/ADt1WjOM5qCOYyn82TNp2OE2uUtAlcsCM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org; spf=pass smtp.mailfrom=mailbox.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b=hkpRxZnV; arc=none smtp.client-ip=80.241.56.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mailbox.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b="hkpRxZnV" Received: from smtp1.mailbox.org (smtp1.mailbox.org [10.196.197.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-201.mailbox.org (Postfix) with ESMTPS id 4fBdGF2LM5z9sRl; Thu, 12 Feb 2026 15:38:45 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1770907125; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/tASHD0fqztvwzzYhG9wjA3X6Sb887HuRt+4PzQxJS8=; b=hkpRxZnV4NZ8j1b1klMnWvP1cEFlt4/bJdJBzk3P8iXEt+NmPgvT+JdunIi7ZAYa6dsVDw 6sKIkgJrYfcHS9Tvyucnz+KLHnl3lgC2ObC/himMo/eRH9pGUnE2pI9AkpCink6X8rFtcd wp0k1PSqOwpdbkdtO1o2SUN1ybCvMRxI/ek4OP7tRvpJubVdw4HOluLuZWYHa8wWXBIXmS pGURxTQqKWWxC3VZGkWJFVWqPkqJ0w+bzPwDc/I3Ecu4XAvymoqBPqS3kHOnjTI+DljDp3 pCF8DZrbxLAp/lwtwXmdMuGdbyS8tQ8fRY9s3u/EIgwuPREyWcub6oS43KkNdw== Message-ID: Date: Thu, 12 Feb 2026 15:38:40 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] drm/imagination: Convert to dev_pm_domain_{at,de}tach_list() To: Matt Coster Cc: Geert Uytterhoeven , Thorsten Leemhuis , Frank Binns , Brajesh Gupta , Alessio Belle , Alexandru Dadu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , "dri-devel@lists.freedesktop.org" , "linux-pm@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "regressions@lists.linux.dev" References: <194465eda54d1f852a9226cf691ddc5aa208e0a3.1769097977.git.geert+renesas@glider.be> <3e0def93-2f6c-4bcf-8ee5-bf607f2ca382@imgtec.com> Content-Language: en-US From: Marek Vasut In-Reply-To: <3e0def93-2f6c-4bcf-8ee5-bf607f2ca382@imgtec.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-MBO-RS-META: m5na1oyisi5kf9qja4q3ixf1e5yo8yfw X-MBO-RS-ID: 5c189705801aa560717 On 2/12/26 10:00 AM, Matt Coster wrote: > On 11/02/2026 19:17, Marek Vasut wrote: >> On 1/23/26 2:50 PM, Geert Uytterhoeven wrote: >> >> Hello everyone, >> >>> On Fri, 23 Jan 2026 at 14:36, Matt Coster wrote: >>>> On 22/01/2026 16:08, Geert Uytterhoeven wrote: >>>>> Call the dev_pm_domain_attach_list() and dev_pm_domain_detach_list() >>>>> helpers instead of open-coding multi PM Domain handling. >>>>> >>>>> This changes behavior slightly: >>>>> - The new handling is also applied in case of a single PM Domain, >>>>> - PM Domains are now referred to by index instead of by name, but >>>>> "make dtbs_check" enforces the actual naming and ordering anyway, >>>>> - There are no longer device links created between virtual domain >>>>> devices, only between virtual devices and the parent device. >>>> >>>> We still need this guarantee, both at start and end of day. In the >>>> current implementation dev_pm_domain_attach_list() iterates forwards, >>>> but so does dev_pm_domain_detach_list(). Even if we changed that, I'd >>>> prefer not to rely on the implementation details when we can declare the >>>> dependencies explicitly. >>> >>> Note that on R-Car, the PM Domains are nested (see e.g. r8a7795_areas[]), >>> so they are always (un)powered in the correct order. But that may not >>> be the case in the integration on other SoCs. >>> >>>> We had/have a patch (attached) kicking around internally to use the >>>> *_list() functions but keep the inter-domain links in place; it got held >>>> up by discussions as to whether we actually need those dependencies for >>>> the hardware to behave correctly. Your patch spurred me to run around >>>> the office and nag people a bit, and it seems we really do need to care >>>> about the ordering. >>> >>> OK. >>> >>>> Can you add the links back in for a V2 or I can properly send the >>>> attached patch instead, I don't mind either way. >>> >>> Please move forward with your patch, you are the expert. >>> I prefer not to be blamed for any breakage ;-) >> >> Has there been any progress on fixing this kernel crash ? >> >> There are already two proposed solutions, but no fix is upstream. >> > > Yes and no. Our patch to use dev_pm_domain_attach_list() has landed in > drm-misc-next as commit e19cc5ab347e3 ("drm/imagination: Use > dev_pm_domain_attach_list()"), but this does not fix the underlying > issue of missing synchronization in the PM core[1] is still unresolved > as far as I'm aware. OK, but the pvr driver can currently easily crash the kernel on boot if firmware is missing, so that should be fixed soon, right ? I added the regressions list onto CC, because this seems like a problem worth tracking.