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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 83A39C79FB9 for ; Thu, 10 Sep 2026 12:37:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=oDPzwY2NdLzoJImbXz0vGW7B4amstayS32YAA47E5/Q=; b=J49mr3PsLh+IBl/+dpECEnzfWG lW+l4Qh8EDwza7VbL7PERTX5gDtnjcvg/Gyp3QkLpdTtAVRS25TutNyFEz4Ipjih4f3RvGN8zDv8J flJopOgy/4nJS7qbnvKimOxoUfYNfivrLgv8Eo1qn3onWkTuyYkRhSqadG9e4/dWO9QLJXL0b0PwI 4cXR4V7j5J/n467Z8D+yLFTtGnc+kb3MbPy4B2izttf7KOygz4Slx2NZ7f8WC1AtXqFuj4/MtIHvt eki/q05E+2koNRs1jfIB8/4RNTZ1oBtv/0iOdhHJ5oOxFwvDxmB0AD9zEbb+dZ9bqkZHhJxd1uH1x aPM/5fXA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x4e25-0000000EM1y-2AOu; Thu, 10 Sep 2026 12:37:37 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x4e21-0000000EM0g-3Una for linux-arm-kernel@lists.infradead.org; Thu, 10 Sep 2026 12:37:36 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4596F153B; Thu, 10 Sep 2026 05:37:28 -0700 (PDT) Received: from [10.2.212.23] (e121345-lin.cambridge.arm.com [10.2.212.23]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 034B03F7B4; Thu, 10 Sep 2026 05:37:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1789043851; bh=AZwDqHdBjqPCn/h9+VhDsgEtjNFCuMURPnIg3aiP66c=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=glwg5KbI4A+6EtBbJdGrMmvmGDTyxTKM5xkPl2GjCRh4g6oOCojo0tG6Nvp/BsP5W ppBt0z61poix3LIUOZVeyM697EZsNnDjwOJ4hujDmg4WZboVhhieMDl1ggKOj7h5At vee/0D7kRuE8CZtW0DhOab3JKWwY/k4PBXOl3d3o= Message-ID: Date: Thu, 10 Sep 2026 13:37:29 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] perf/arm-cmn: Fix wp_dev_sel2 setting for multi-DTM configurations To: Shouping Wang , will@kernel.org Cc: mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, peter.du@hj-micro.com, andy.xu@hj-micro.com References: <2fb3bda7-cd64-4dc0-99f8-c0fda8d42cf9@arm.com> <20260910114601.165237-1-allen.wang@hj-micro.com> From: Robin Murphy Content-Language: en-GB In-Reply-To: <20260910114601.165237-1-allen.wang@hj-micro.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260910_053733_958120_EAE0724D X-CRM114-Status: GOOD ( 19.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 10/09/2026 12:46 pm, Shouping Wang wrote: > When MXP_MULTIPLE_DTM_EN is TRUE, each DTM will monitor at most > two device ports. In this case, {wp_dev_sel2, wp_dev_sel} will > only use values 2'b00 and 2'b01 per DTM. Poor documentation strikes again! > Previously the setting allowed values beyond the supported range > per DTM, which could cause each DTM to select invalid ports when > MXP_MULTIPLE_DTM_EN is TRUE. > > Fix this by only setting CMN_DTM_WPn_CONFIG_WP_DEV_SEL2 when > !multi_dtm. Reviewed-by: Robin Murphy Thanks for the fix! Robin. > Fixes: 60d1504070c2 ("perf/arm-cmn: Support new IP features") > Signed-off-by: Shouping Wang > --- > > Changes in v2: > - Made the setting of CMN_DTM_WPn_CONFIG_WP_DEV_SEL2 conditional on > !multi_dtm, instead of clamping with dev %= 2. > - Refactored is_cmn600 to use cmn->part directly. > - Updated the commit message. > > Link to v1: https://lore.kernel.org/lkml/20260819105443.668784-1-allen.wang@hj-micro.com/ > > drivers/perf/arm-cmn.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c > index 6e5cc4086a9e..7e7590381171 100644 > --- a/drivers/perf/arm-cmn.c > +++ b/drivers/perf/arm-cmn.c > @@ -1393,13 +1393,14 @@ static void arm_cmn_claim_wp_idx(struct arm_cmn_dtm *dtm, > > static u32 arm_cmn_wp_config(struct perf_event *event, int wp_idx) > { > + struct arm_cmn *cmn = to_cmn(event->pmu); > u32 config; > u32 dev = CMN_EVENT_WP_DEV_SEL(event); > u32 chn = CMN_EVENT_WP_CHN_SEL(event); > u32 grp = CMN_EVENT_WP_GRP(event); > u32 exc = CMN_EVENT_WP_EXCLUSIVE(event); > u32 combine = CMN_EVENT_WP_COMBINE(event); > - bool is_cmn600 = to_cmn(event->pmu)->part == PART_CMN600; > + bool is_cmn600 = cmn->part == PART_CMN600; > > /* CMN-600 supports only primary and secondary matching groups */ > if (is_cmn600) > @@ -1407,8 +1408,11 @@ static u32 arm_cmn_wp_config(struct perf_event *event, int wp_idx) > > config = FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_DEV_SEL, dev) | > FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_CHN_SEL, chn) | > - FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_GRP, grp) | > - FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_DEV_SEL2, dev >> 1); > + FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_GRP, grp); > + > + if (!cmn->multi_dtm) > + config |= FIELD_PREP(CMN_DTM_WPn_CONFIG_WP_DEV_SEL2, dev >> 1); > + > if (exc) > config |= is_cmn600 ? CMN600_WPn_CONFIG_WP_EXCLUSIVE : > CMN_DTM_WPn_CONFIG_WP_EXCLUSIVE;