From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51F22C761AF for ; Thu, 30 Mar 2023 10:06:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230183AbjC3KG2 (ORCPT ); Thu, 30 Mar 2023 06:06:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229869AbjC3KG1 (ORCPT ); Thu, 30 Mar 2023 06:06:27 -0400 X-Greylist: delayed 1009 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 30 Mar 2023 03:06:26 PDT Received: from mail.kapsi.fi (mail.kapsi.fi [IPv6:2001:67c:1be8::25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6495110DD; Thu, 30 Mar 2023 03:06:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kapsi.fi; s=20161220; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=6FbbQ2ARgg8AsSn+bHuiJ5XTJvM+84zfBTQ14KGT7uk=; b=x3pPtY5rtNGer+M7TdN8dXoPQV +kUlAL2SpciFvZArogkDfRLz3bepXG26F6HaEdLwTaR0NxsslLOWTvX43HLG7757HcSeXNzHhYZ0y CBGwmLV99sqQ0bYRXh5wNtfYy33ai+0sz7XPDtcqhRPivrXG/BQC/LVtl1u/iMQQS17rQPoc2+4j/ 6/gw3aFthMu2UibfE21zY8r8/F7RAyT+o4uTG7fM6CPiSK1q1A4yJsZqi2JhrPcc1yG5+gt1ilhgF lVn/g68TltXJlPgx23LhH+cY/XrDrhW4NjJYXx/t2F5BDP/qTRVBstMgyjkQS9q2OxmgiV5jYRaZn EhRL4aKw==; Received: from 91-158-25-70.elisa-laajakaista.fi ([91.158.25.70] helo=[192.168.1.10]) by mail.kapsi.fi with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1phpAW-000Bjr-Kj; Thu, 30 Mar 2023 13:06:08 +0300 Message-ID: <204e0435-c544-8727-e892-9fc69b8d691d@kapsi.fi> Date: Thu, 30 Mar 2023 13:06:06 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 Subject: Re: [PATCH v2] thermal: tegra-bpmp: Handle offline zones Content-Language: en-US To: Daniel Lezcano , "Rafael J. Wysocki" , Amit Kucheria , Zhang Rui , Thierry Reding , Jonathan Hunter Cc: Mikko Perttunen , linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230330094904.2589428-1-cyndis@kapsi.fi> From: Mikko Perttunen In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 91.158.25.70 X-SA-Exim-Mail-From: cyndis@kapsi.fi X-SA-Exim-Scanned: No (on mail.kapsi.fi); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 3/30/23 13:03, Daniel Lezcano wrote: > On 30/03/2023 11:49, Mikko Perttunen wrote: >> From: Mikko Perttunen >> >> Thermal zones located in power domains may not be accessible when >> the domain is powergated. In this situation, reading the temperature >> will return -BPMP_EFAULT. When evaluating trips, BPMP will internally >> use -256C as the temperature for offline zones. > >> For smooth operation, for offline zones, return -EAGAIN when reading >> the temperature and allow registration of zones even if they are >> offline during probe. > > I think it makes more sense to check if the power domain associated with > the device is powered up and if not return -EPROBE_DEFER. The power domains in question are related to computer vision engines that only get powered on when in use, possibly never if the user doesn't run a computer vision workload on the system. We still want other thermal zones to be available. Mikko > > >> Signed-off-by: Mikko Perttunen >> --- >> v2: >> * Adjusted commit message. >> * Patch 2/2 dropped for now since it is more controversial, >>    and this patch is more critical. >> >>   drivers/thermal/tegra/tegra-bpmp-thermal.c | 9 ++++++++- >>   1 file changed, 8 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/thermal/tegra/tegra-bpmp-thermal.c >> b/drivers/thermal/tegra/tegra-bpmp-thermal.c >> index f5fd4018f72f..4ffc3bb3bf35 100644 >> --- a/drivers/thermal/tegra/tegra-bpmp-thermal.c >> +++ b/drivers/thermal/tegra/tegra-bpmp-thermal.c >> @@ -52,6 +52,8 @@ static int __tegra_bpmp_thermal_get_temp(struct >> tegra_bpmp_thermal_zone *zone, >>       err = tegra_bpmp_transfer(zone->tegra->bpmp, &msg); >>       if (err) >>           return err; >> +    if (msg.rx.ret == -BPMP_EFAULT) >> +        return -EAGAIN; >>       if (msg.rx.ret) >>           return -EINVAL; >> @@ -259,7 +261,12 @@ static int tegra_bpmp_thermal_probe(struct >> platform_device *pdev) >>           zone->tegra = tegra; >>           err = __tegra_bpmp_thermal_get_temp(zone, &temp); >> -        if (err < 0) { >> + >> +        /* >> +         * Sensors in powergated domains may temporarily fail to be read >> +         * (-EAGAIN), but will become accessible when the domain is >> powered on. >> +         */ >> +        if (err < 0 && err != -EAGAIN) { >>               devm_kfree(&pdev->dev, zone); >>               continue; >>           } >