From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x224IlHhXkrgXVOjZZUYkWwy30Ld4RnmbUGdHG2SuBFH+fyg53GK4UtKxWQokocRQzCm498G9 ARC-Seal: i=1; a=rsa-sha256; t=1519646750; cv=none; d=google.com; s=arc-20160816; b=d5eLL0Szr0lbOplxONr6K9+0kkPUI8hVLMXX1R2kQ/kpa20SAlu9gP9x1pwmKPuUzM x82EiLdp0kNe6sgq6iIzt2+DLlhotPYdxjATByEVv/fNfLqP/mSvQ11t8d8vSn03CtkB 0e4xHSyAz0bgQZRj3UBcnKNShs/jLWW6NCe56jFxRL+pjJwD5SVZ7+Gjh9sOLmPve+D5 5XtMlZdDo7UAPny9cQkbo/vaL4z+l3fHCzfd7T/GoMlPWsaO9m5WGfuWhbz4fwLhye8Z ltnIV5wr6kGPNSVBqpZU+5Y+3rQ7+tOCIsx9ozrqqnIzBY824C+w8378mB4PsqoEjYrH 6ByQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:organization:in-reply-to:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :arc-authentication-results; bh=Z8pp8UJXveblnSuQG9DRYUIVg1T8hYsbtsz172yu5xA=; b=JS/+qa0HTid7iNoWrJuiWy1qeo1otmfQhKRGi/mtT6Z5N8JvcIQ/1w8cINNWXFaoiE QpdDSznZEpqFuT8UJ+udF16GojZ2cZPUKhyfv4EoysAD+oZV8sTmuyXnpL+NlKVbxA12 Y+3zaBw/MJ3HzVDl18aLwDVrng/98kM7aUBvfrxQG7Sg04AqeTe0s/ufFm5e7Vlh5QQf uyqZB6p40lOoWW2c7GlOqUzLa84AzZ3TX3pSpmt1yjUmHPeEOKxRTEiRwndIB3RZqSfo VFRQFW1HD+kaQz1Mh+qnHUZiqbBPIHv1sS/hTnbs2wYcqUXdRH+czN0t5bQRgQjOcMPz /gFw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of mika.westerberg@linux.intel.com designates 134.134.136.31 as permitted sender) smtp.mailfrom=mika.westerberg@linux.intel.com Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of mika.westerberg@linux.intel.com designates 134.134.136.31 as permitted sender) smtp.mailfrom=mika.westerberg@linux.intel.com X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,396,1515484800"; d="scan'208";a="23198994" Date: Mon, 26 Feb 2018 14:05:34 +0200 From: Mika Westerberg To: Lukas Wunner Cc: Bjorn Helgaas , "Rafael J. Wysocki" , Linux PCI , Valdis Kletnieks , Mathias Nyman , Linux PM , "Rafael J. Wysocki" , Linux Kernel Mailing List , Peter Wu , Qipeng Zha , Greg Kroah-Hartman , Andreas Noever , Dave Airlie , Qi Zheng Subject: Re: [PATCH v1 2/2] PCI: Allow user to request power management of conventional and hotplug bridges Message-ID: <20180226120534.GO27191@lahna.fi.intel.com> References: <151908155159.37696.9710083237704994886.stgit@bhelgaas-glaptop.roam.corp.google.com> <151908204614.37696.12828004282495415825.stgit@bhelgaas-glaptop.roam.corp.google.com> <20180220181554.GA32228@bhelgaas-glaptop.roam.corp.google.com> <20180222131834.GA5527@wunner.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180222131834.GA5527@wunner.de> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.9.1 (2017-09-22) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1592872976935903628?= X-GMAIL-MSGID: =?utf-8?q?1593465111000678477?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Thu, Feb 22, 2018 at 02:18:34PM +0100, Lukas Wunner wrote: > We do need runtime PM on hotplug ports to power off Thunderbolt > controllers when nothing is plugged in. That saves 1.5 W, so a > noticeable amount of power. I was going to respin the series one > of these days, I think the best I can do is continue to forbid > runtime PM on hotplug ports by default, but whitelist it for > Thunderbolt and allow manually enabling it on other platforms via > the command line. That way, vendors are put in a position to > validate their platforms for runtime PM of hotplug ports, and > perhaps someday we can enable it for all platforms by default, > but with a BIOS cut-off date. AFAIK Windows started to enable runtime PM (RTD3) for native PCIe hotplug ports with the latest release (I guess it's the RS3 release) but only when there is a special ACPI _DSD property ("HotPlugSupportInD3") associated with the root port. I think we can take advantage of that in Linux as well and I already have a patch series to enable runtime PM for such ports but I haven't been able to test it properly yet.