From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 08C5B6A8D2; Thu, 19 Feb 2026 09:40:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771494030; cv=none; b=hOCgVIFzPxFjaM4J14N178zgXB35pjYRT5dtc+heM3R21Lf6FabRV7hO9D5UfBmEtsqvWMi1NDJPQcp+ZOZJhbHSCODltJUPfIwFF+syK1sQKaoPJ6DvcAz9Hwuvih6nsIV8W87YHygU0X/PrGvJowiTBheKZDbynMPl1beXO1k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771494030; c=relaxed/simple; bh=O9A62UZYVCQd00W6K9cEgotwzC6b7jDjES67GKeH5MI=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=bD8Krp5lRkiKTKYTgsLjWv4DSXjv21V2hZKy9m3HTSQQpn1ysK5IEqEtp9oPgvbcMLQmTTH27jpt0kYZpCuyR1VN3tVNRaKUVWLUbQsYsxV+sE55UsBdPl0aX03c/ZtVxN1BTZbn7z3++w7Km9qTwcaIi8PNRuhgrrNm06DksKg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.224.83]) by frasgout.his.huawei.com (SkyGuard) with ESMTPS id 4fGpJV5YvHzJ46Zg; Thu, 19 Feb 2026 17:40:10 +0800 (CST) Received: from dubpeml500005.china.huawei.com (unknown [7.214.145.207]) by mail.maildlp.com (Postfix) with ESMTPS id E984340569; Thu, 19 Feb 2026 17:40:23 +0800 (CST) Received: from localhost (10.203.177.15) by dubpeml500005.china.huawei.com (7.214.145.207) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Thu, 19 Feb 2026 09:40:23 +0000 Date: Thu, 19 Feb 2026 09:40:21 +0000 From: Jonathan Cameron To: Besar Wicaksono CC: , , , , , , , , , , , , , , , , Subject: Re: [PATCH v2 3/8] perf/arm_cspmu: Add arm_cspmu_acpi_dev_get Message-ID: <20260219094021.0000465d@huawei.com> In-Reply-To: <20260218145809.1622856-4-bwicaksono@nvidia.com> References: <20260218145809.1622856-1-bwicaksono@nvidia.com> <20260218145809.1622856-4-bwicaksono@nvidia.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml100010.china.huawei.com (7.191.174.197) To dubpeml500005.china.huawei.com (7.214.145.207) On Wed, 18 Feb 2026 14:58:04 +0000 Besar Wicaksono wrote: > Add interface to get ACPI device associated with the > PMU. This ACPI device may contain additional properties > not covered by the standard properties. > > Reviewed-by: Ilkka Koskinen > Signed-off-by: Besar Wicaksono Hi Besar, A drive by review as I was curious. A few comments inline. > --- > drivers/perf/arm_cspmu/arm_cspmu.c | 22 +++++++++++++++++++++- > drivers/perf/arm_cspmu/arm_cspmu.h | 17 ++++++++++++++++- > 2 files changed, 37 insertions(+), 2 deletions(-) > > diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c > index 34430b68f602..ab2479c048bb 100644 > --- a/drivers/perf/arm_cspmu/arm_cspmu.c > +++ b/drivers/perf/arm_cspmu/arm_cspmu.c > @@ -16,7 +16,7 @@ > * The user should refer to the vendor technical documentation to get details > * about the supported events. > * > - * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved. > + * Copyright (c) 2022-2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved. > * > */ > > @@ -1132,6 +1132,26 @@ static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu) > > return 0; > } > + > +struct acpi_device *arm_cspmu_acpi_dev_get(const struct arm_cspmu *cspmu) > +{ > + char hid[16]; > + char uid[16]; Might as well do char hid[16] = { }; char uid[16] = { }; and drop the memsets below. > + const struct acpi_apmt_node *apmt_node; > + > + apmt_node = arm_cspmu_apmt_node(cspmu->dev); > + if (!apmt_node || apmt_node->type != ACPI_APMT_NODE_TYPE_ACPI) > + return NULL; > + > + memset(hid, 0, sizeof(hid)); > + memset(uid, 0, sizeof(uid)); > + > + memcpy(hid, &apmt_node->inst_primary, sizeof(apmt_node->inst_primary)); > + snprintf(uid, sizeof(uid), "%u", apmt_node->inst_secondary); > + > + return acpi_dev_get_first_match_dev(hid, uid, -1); > +} > +EXPORT_SYMBOL_GPL(arm_cspmu_acpi_dev_get); > #else > static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu) > { > diff --git a/drivers/perf/arm_cspmu/arm_cspmu.h b/drivers/perf/arm_cspmu/arm_cspmu.h > index cd65a58dbd88..320096673200 100644 > --- a/drivers/perf/arm_cspmu/arm_cspmu.h > +++ b/drivers/perf/arm_cspmu/arm_cspmu.h > @@ -1,13 +1,14 @@ > /* SPDX-License-Identifier: GPL-2.0 > * > * ARM CoreSight Architecture PMU driver. > - * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved. > + * Copyright (c) 2022-2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved. > * > */ > > #ifndef __ARM_CSPMU_H__ > #define __ARM_CSPMU_H__ > > +#include > #include > #include > #include > @@ -255,4 +256,18 @@ int arm_cspmu_impl_register(const struct arm_cspmu_impl_match *impl_match); > /* Unregister vendor backend. */ > void arm_cspmu_impl_unregister(const struct arm_cspmu_impl_match *impl_match); > > +#if defined(CONFIG_ACPI) This isn't the same gate as used for whether the function is built. I think that's #if defined(CONFIG_ACPI) && defined(CONFIG_ARM64) Whilst it might work to have them different today I think this is a little more fragile than would be ideal. The ARM64 bit seems to be there to allow COMPILE_TEST for ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU and to me that smells like a stub or Kconfig dependency missing. > +/** > + * Get ACPI device associated with the PMU. > + * The caller is responsible for calling acpi_dev_put() on the returned device. > + */ > +struct acpi_device *arm_cspmu_acpi_dev_get(const struct arm_cspmu *cspmu); > +#else > +static inline struct acpi_device * > +arm_cspmu_acpi_dev_get(const struct arm_cspmu *cspmu) > +{ > + return NULL; > +} > +#endif > + > #endif /* __ARM_CSPMU_H__ */