From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH V2] PM / Domains: Return -EPROBE_DEFER if we fail to init or turn-on domain Date: Thu, 6 Aug 2015 12:46:23 +0100 Message-ID: <55C3490F.20307@nvidia.com> References: <1438334400-26367-1-git-send-email-jonathanh@nvidia.com> <55C0C4D3.2050600@nvidia.com> <1911839.6SetkcFuZL@vostro.rjw.lan> <55C30FE4.9080206@nvidia.com> <55C31AA9.8050202@nvidia.com> <55C3284F.8070305@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from hqemgate16.nvidia.com ([216.228.121.65]:4028 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750758AbbHFLqa (ORCPT ); Thu, 6 Aug 2015 07:46:30 -0400 In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Geert Uytterhoeven Cc: "Rafael J. Wysocki" , Ulf Hansson , Kevin Hilman , Linux PM list Hi Geert, On 06/08/15 12:26, Geert Uytterhoeven wrote: > Hi Jon, > > On Thu, Aug 6, 2015 at 11:26 AM, Jon Hunter wrote: > > [...] > >>>>>>>>> This causes a regression for platforms where: >>>>>>>>> 1. DT describes the hardware power domains, and >>>>>>>>> 2. The boot loader or reset state has enabled all power domains, and >>>>>>>>> 3. Linux doesn't have a driver for the power controller yet. >>>>>>>>> >>>>>>>>> Before, devices for which the PM domain couldn't be found just probed and >>>>>>>>> worked, Now, these devices don't probe anymore, and the kernel fails to boot. > > [...] > >> It still sounds to me that the nodes should be disabled/removed from the >> dtb. Having a dynamic way to do this would be useful, I can see. > > I had a quick look, and it already seem to exist.. > Hence on platforms not implementing power controllers yet, the early platform > code could do: > > struct device_node *np; > for_each_node_with_property(dn, "power-domains") > of_remove_property(np, "power-domains"); > > Haven't tested that yet, though... Yes that could be an option, however, it would mean doing this type of thing for various types of nodes. You mentioned dma was another case. > Heck, even the core power domain code could do that, if > CONFIG_PM_GENERIC_DOMAINS=n ;-) Yes that's true. Hopefully it would WARN too ;-) Jon ----------------------------------------------------------------------------------- This email message is for the sole use of the intended recipient(s) and may contain confidential information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message. -----------------------------------------------------------------------------------