From patchwork Mon Feb 7 17:37:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Cavallari X-Patchwork-Id: 542126 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 6256AC4332F for ; Mon, 7 Feb 2022 17:53:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235334AbiBGRwN (ORCPT ); Mon, 7 Feb 2022 12:52:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238203AbiBGRn1 (ORCPT ); Mon, 7 Feb 2022 12:43:27 -0500 Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C313C0401DA for ; Mon, 7 Feb 2022 09:43:26 -0800 (PST) Received: from evilbit.green-communications.fr ([92.154.77.116]) by mrelayeu.kundenserver.de (mreue009 [213.165.67.103]) with ESMTPSA (Nemesis) id 1MKsaz-1nbg9L1Ran-00LEoH; Mon, 07 Feb 2022 18:38:06 +0100 From: Nicolas Cavallari To: Felix Fietkau , Lorenzo Bianconi , Ryder Lee , Shayne Chen , Sean Wang Cc: Kalle Valo , linux-wireless@vger.kernel.org Subject: [PATCH RFC 1/3] mt76: mt7915e: Fix degraded performance after temporary overheat Date: Mon, 7 Feb 2022 18:37:45 +0100 Message-Id: <20220207173747.7997-1-nicolas.cavallari@green-communications.fr> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 X-Provags-ID: V03:K1:Y8+taFohQYdEKpCEm8w7Bui8N7fbtuwdis6JaWIRccn3+CZ6t+O +U9vcEemMppB9nlNwxVB6gwVlO9mevqNU5UJagbjaWW8o7YJUMaTmYEj+5F+j4twHgDvTWu vUzl3UKLzCBZJVbxsK83HwJG+kJUsW6jShgpG9ob+f5Z2/kxrie3leHHNix27W8l6KdAyR6 4cVaqanNmroTHei9tzMkA== X-UI-Out-Filterresults: notjunk:1;V03:K0:YJShyVz0SVc=:EVh7+qJZm2R8PnBHO1gXKg eOFP/URom1LjUa0CKFW1pIS1ut+9txZff+93aznwOqAmUeWJCeAw6WQjYxMMhHAGDhlr2oGQv jpZsGPuGOqLHi7ztFFY1bXi5SdGgKvhcyI4YHkGwssKXKVEPQJVjDru7dywxmgbgKk64ZqLFJ ns2aTw1gn7aRfmJx/tNj6UwGs20HwNjlBcXsBfO8MaGT2FXk/Q02Ub5/ue9c2GojI5PS0ABNv qEiz0E/7qAc8QnY2o8PGq97lqvOR6qjv2zPH8+9s6ZQopIdrwzstXQXBKBPNKVEPFVOKOFsbo OFUhcMjRjTp/pcqwZDy7Jn9on6HNFugnDjl3rlMlQcDLjCT6ikH78p8oAeBw0LHBAqVZkYBPv gIy5kxMIoUqMBOf9HxW0Mp2jb0/+YckvEmDKty56ggASw4Pkv5rRahkVkNRHmaaJOBupsvRO0 Qb9BmmUkbC7I/hlI9wWSuWPpyUOfE5OOlQRUHqboBft/1hr5JXElnHDaQCdbmo8IgtePdnV4Q gvQSV+uovk30/fz1M70tAyq5/l16thjhPk1wRlcmgNysPkWlDPmor+UDY5ivd1ADUa8KEN4TW 1sbGf21cDq7WPGsxV81G94muvrd5Oxso8mHepIZMYSZNeRpwZVnKM9wNjRvAjVejcz6jOr/MS J0SMCQ4ohjNYIjUfRUX8xTXlsqEeFtruttoVolI77zsxPm4ooIN3BuCBzfM100lRsuLTbLhRe FurrU259q2ca6cDUduh9KDTm+XoG+376KEKMoQ== Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org mt7915e registers a cooling_device with wrong semantics: 1. cooling_device expect that higher states values should cool more, but mt7915e did the opposite... with the exception of state == 0, which should "disable thermal management", but does not seem to have any effect since the previous state is kept. The result is that when the thermal zone heats up a bit and bumps the cooling_device state from 0 to 1 to cool a bit, the performance is destroyed, and when going back from 1 to 0, the performance stays bad. 2. Reading the cooling_device state does not always return the last written state, but can return the actual hardware throttle state, which is different. This is a problem because the mt7915 firmware actually implement the equivalent of a thermal zone with trip points. Setting the cooling device state actually changes the throttles at each trip point, so the following could occur if the first issue is fixed: - thermal subsystem set state to 100% power (state=0) - mt7915e driver set trip throttles to [100%, 50%, 25%, 12%] - hardware heats up and decides to switch to 50% power - thermal subsystem see that power is 50% (state=50), decide to increase it to 60% (state=40) because the rest of the system is cool. - mt7915e driver set trip throttle to [60%, 30%, 15%, 7%] - hardware thus switches to 30% power [race to the bottom continues...] This patch corrects the semantics of the cooling_device to the one that the thermal subsystem expect it. Signed-off-by: Nicolas Cavallari --- drivers/net/wireless/mediatek/mt76/mt7915/init.c | 16 ++++++++++------ .../net/wireless/mediatek/mt76/mt7915/mt7915.h | 2 ++ 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/init.c b/drivers/net/wireless/mediatek/mt76/mt7915/init.c index 2bc9097c5214..d6efbf1a2724 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7915/init.c +++ b/drivers/net/wireless/mediatek/mt76/mt7915/init.c @@ -97,7 +97,7 @@ static int mt7915_thermal_get_max_throttle_state(struct thermal_cooling_device *cdev, unsigned long *state) { - *state = MT7915_THERMAL_THROTTLE_MAX; + *state = MT7915_CDEV_THROTTLE_MAX; return 0; } @@ -108,7 +108,7 @@ mt7915_thermal_get_cur_throttle_state(struct thermal_cooling_device *cdev, { struct mt7915_phy *phy = cdev->devdata; - *state = phy->throttle_state; + *state = phy->cdev_state; return 0; } @@ -120,20 +120,24 @@ mt7915_thermal_set_cur_throttle_state(struct thermal_cooling_device *cdev, struct mt7915_phy *phy = cdev->devdata; int ret; - if (state > MT7915_THERMAL_THROTTLE_MAX) + if (state > MT7915_CDEV_THROTTLE_MAX) return -EINVAL; if (phy->throttle_temp[0] > phy->throttle_temp[1]) return 0; - if (state == phy->throttle_state) + if (state == phy->cdev_state) return 0; - ret = mt7915_mcu_set_thermal_throttling(phy, state); + // cooling_device convention: 0 = no cooling, more = more cooling + // mcu convention: 1 = max cooling, more = less cooling + ret = mt7915_mcu_set_thermal_throttling(phy, + MT7915_THERMAL_THROTTLE_MAX + - state); if (ret) return ret; - phy->throttle_state = state; + phy->cdev_state = state; return 0; } diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h b/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h index 0403912a521d..cf4c8d2dcc60 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h +++ b/drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h @@ -49,6 +49,7 @@ #define MT7915_CFEND_RATE_11B 0x03 /* 11B LP, 11M */ #define MT7915_THERMAL_THROTTLE_MAX 100 +#define MT7915_CDEV_THROTTLE_MAX 99 #define MT7915_SKU_RATE_NUM 161 @@ -218,6 +219,7 @@ struct mt7915_phy { struct ieee80211_vif *monitor_vif; struct thermal_cooling_device *cdev; + u8 cdev_state; u8 throttle_state; u32 throttle_temp[2]; /* 0: critical high, 1: maximum */