From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754239AbeALFrq (ORCPT + 1 other); Fri, 12 Jan 2018 00:47:46 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:35262 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752576AbeALFrn (ORCPT ); Fri, 12 Jan 2018 00:47:43 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D43EA601D4 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vivek.gautam@codeaurora.org Subject: Re: [PATCH v5 1/6] base: power: runtime: Export pm_runtime_get/put_suppliers To: "Rafael J. Wysocki" References: <1515492109-753-1-git-send-email-vivek.gautam@codeaurora.org> <1515492109-753-2-git-send-email-vivek.gautam@codeaurora.org> Cc: Joerg Roedel , Rob Herring , Mark Rutland , "Rafael J. Wysocki" , Greg Kroah-Hartman , Rob Clark , Will Deacon , Robin Murphy , Stephen Boyd , "open list:AMD IOMMU (AMD-VI)" , "devicetree@vger.kernel.org" , Linux Kernel Mailing List , Linux PM , dri-devel , freedreno@lists.freedesktop.org, Len Brown , Pavel Machek , David Airlie , Sricharan R , Marek Szyprowski , architt@codeaurora.org, linux-arm-msm From: Vivek Gautam Message-ID: <65d04510-bd88-7afe-27b5-d5e9cb416949@codeaurora.org> Date: Fri, 12 Jan 2018 11:17:33 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On 01/12/2018 04:23 AM, Rafael J. Wysocki wrote: > On Tue, Jan 9, 2018 at 11:01 AM, Vivek Gautam > wrote: >> The device link allows the pm framework to tie the supplier and >> consumer. So, whenever the consumer is powered-on the supplier >> is powered-on first. >> >> There are however cases in which the consumer wants to power-on >> the supplier, but not itself. >> E.g., A Graphics or multimedia driver wants to power-on the SMMU >> to unmap a buffer and finish the TLB operations without powering >> on itself. Some of these unmap requests are coming from the >> user space when the controller itself is not powered-up, and it >> can be huge penalty in terms of power and latency to power-up >> the graphics/mm controllers. >> There can be an argument that the supplier should handle this case >> on its own and there should not be a need for the consumer to >> power-on the supplier. But as discussed on the thread [1] about >> ARM-SMMU runtime pm, we don't want to introduce runtime pm calls >> in atomic path in arm_smmu_unmap. >> >> [1] https://patchwork.kernel.org/patch/9827825/ >> >> Signed-off-by: Vivek Gautam > Acked-by: Rafael J. Wysocki > > Please feel free to route this along with the rest of the series. Thanks Rafael. regards Vivek > > Thanks! > >> --- >> >> * This is v2 of the patch [1]. Adding it to this patch series. >> [1] https://patchwork.kernel.org/patch/10102447/ >> >> drivers/base/power/runtime.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c >> index 6e89b51ea3d9..06a2a88fe866 100644 >> --- a/drivers/base/power/runtime.c >> +++ b/drivers/base/power/runtime.c >> @@ -1579,6 +1579,7 @@ void pm_runtime_get_suppliers(struct device *dev) >> >> device_links_read_unlock(idx); >> } >> +EXPORT_SYMBOL_GPL(pm_runtime_get_suppliers); >> >> /** >> * pm_runtime_put_suppliers - Drop references to supplier devices. >> @@ -1597,6 +1598,7 @@ void pm_runtime_put_suppliers(struct device *dev) >> >> device_links_read_unlock(idx); >> } >> +EXPORT_SYMBOL_GPL(pm_runtime_put_suppliers); >> >> void pm_runtime_new_link(struct device *dev) >> { >> -- >> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member >> of Code Aurora Forum, hosted by The Linux Foundation >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project