From patchwork Mon Dec 5 19:46:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 29924 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:f944:0:0:0:0:0 with SMTP id q4csp2443827wrr; Mon, 5 Dec 2022 11:50:49 -0800 (PST) X-Google-Smtp-Source: AA0mqf5JJxpdt8oakKawxRxTJDAPQeJjECg9UNYcsGKEVIEDTiW5LN/elpkzy5QTMHJ084IvQ48+ X-Received: by 2002:a17:906:32d9:b0:7ae:31a0:5727 with SMTP id k25-20020a17090632d900b007ae31a05727mr56058659ejk.540.1670269848998; Mon, 05 Dec 2022 11:50:48 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1670269848; cv=none; d=google.com; s=arc-20160816; b=Cg/ktI7mIyut0WAK+k9RrQzPXYEmjKA2jNyv9Kuhb+PtklfBbsHO86Pd5sFmqK+AMc lHMJKz3ourjzw4ChmikG7ul6GTaECw+MX70l5cZBuxfWIb/2HASWjKZTI+8gPAm5pWCl SrXcecASxaQ6xZ2OWr7qYO8cb6oNDKT4IuZuH+XtTezqBeKc14t+SSmo4y0sZx5pc+Ab 1dBk2QHuH31CLdra1wby6BDzMZdgq4QLxkXwC8BTpSbPI/gHSPrXVAd/hcMDUSrAN4nG xgbj7oAHsjowrqjicK+mGKRq49j7KWM1LCA+7gq6fM1miviO/OE4nvWlppJwAe42EUSi 7olQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from; bh=1VNOOB0OGpays3G5OnI7GUZCtjq/fQNOz+9yV5VHCZU=; b=ZOQLB0pg53YCIIgIPLb8lxVLUGdwrrpjToTw12WH/zorkaRM6kpq8pw2vc1uHqQ6v9 8LJrFTRUNIwwHz6GOqSSEEwMhLHTiy3ezapiNrnAVhEP1m0QurcMoA8xFOX1K0yAN2Hz m/Nl3WtfS4BGeoaob5ILm1Nm5AWxYzkxKzSTxNdRqCBGZFkzR/b1t5t6M3qpO7mKtj3N gQP+IlznWql3vO8kwsgpJcqbbCydVJ2GKmvIOcOOSODrWfF3avKIrV8HlaPymbuxf3F9 aKdnqTCicK2Fj/D7FrpuUZOi2GB5nLUv+i42kPxlS8SoDUSKhz6ZGlwlovdEu+7oM5eh H57g== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id sd12-20020a1709076e0c00b007bddb7980f9si13115458ejc.100.2022.12.05.11.50.26; Mon, 05 Dec 2022 11:50:48 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235208AbiLETtn (ORCPT + 99 others); Mon, 5 Dec 2022 14:49:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235104AbiLETtL (ORCPT ); Mon, 5 Dec 2022 14:49:11 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 7825C2AC47 for ; Mon, 5 Dec 2022 11:46:25 -0800 (PST) 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 92279D6E; Mon, 5 Dec 2022 11:46:26 -0800 (PST) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 7CF583F71A; Mon, 5 Dec 2022 11:46:16 -0800 (PST) From: Robin Murphy To: will@kernel.org, mark.rutland@arm.com Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] perf/arm-cmn: Reset DTM_PMU_CONFIG at probe Date: Mon, 5 Dec 2022 19:46:13 +0000 Message-Id: X-Mailer: git-send-email 2.36.1.dirty MIME-Version: 1.0 X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1751404876882275782?= X-GMAIL-MSGID: =?utf-8?q?1751404876882275782?= Although we treat the DTM counters as free-running such that we're not too concerned about the initial DTM state, it's possible for a previous user to have left DTM counters enabled and paired with DTC counters. Thus if the first events are scheduled using some, but not all, DTMs, the as-yet-unused ones could end up adding spurious increments to the event counts at the DTC. Make sure we sync our initial DTM_PMU_CONFIG state to all the DTMs at probe time to avoid that possibility. Signed-off-by: Robin Murphy --- drivers/perf/arm-cmn.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c index 0b2df72cee9f..81b0dfd511aa 100644 --- a/drivers/perf/arm-cmn.c +++ b/drivers/perf/arm-cmn.c @@ -1862,6 +1862,7 @@ static void arm_cmn_init_dtm(struct arm_cmn_dtm *dtm, struct arm_cmn_node *xp, i dtm->base = xp->pmu_base + CMN_DTM_OFFSET(idx); dtm->pmu_config_low = CMN_DTM_PMU_CONFIG_PMU_EN; + writeq_relaxed(dtm->pmu_config_low, dtm->base + CMN_DTM_PMU_CONFIG); for (i = 0; i < 4; i++) { dtm->wp_event[i] = -1; writeq_relaxed(0, dtm->base + CMN_DTM_WPn_MASK(i));