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 52191C001DF for ; Wed, 2 Aug 2023 02:45:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id: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=ZN6QijUepG89xx8HOazSHkOxk+ttASVTT5uzDiCLh0E=; b=gluEiFxDkIdSPd n1tES3AXWNSy5NYO7yxXdrs9U30IcfzbIT2BzYJ/xHNEBeDTiJ/n7420Y+34IMyJpHNDKq6OPso/F FFLzAeAUZwpYhgaERsAWcQSTwj2TKXgwk99fLu8Y74CL2vKVUXa3lDz+Y3F6PKoKK/pMxVdAohIKP Acboz9jaVCxmoTEB9KUw5zP0c+Z/eCKQSvLOOAXB1/B89QOM1pf41TzAbTI75ASO4Yy/gywCiPH1B 2LQ71qaxqHEX3P0uHSPG/7iddsTHjj0ti8nNgiObgA4EQ4U3GCFdvvOg8iwsCtqYRAfmHfb00ErTr aceOyAiSnr1ADSo2poew==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qR1qw-003o4B-2X; Wed, 02 Aug 2023 02:44:46 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qR1qt-003o3S-1o for linux-arm-kernel@lists.infradead.org; Wed, 02 Aug 2023 02:44:45 +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 A5DDFD75; Tue, 1 Aug 2023 19:45:23 -0700 (PDT) Received: from [10.163.53.180] (unknown [10.163.53.180]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1AF9E3F5A1; Tue, 1 Aug 2023 19:44:37 -0700 (PDT) Message-ID: Date: Wed, 2 Aug 2023 08:14:36 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH V2 1/4] arm_pmu: acpi: Refactor arm_spe_acpi_register_device() Content-Language: en-US To: Will Deacon Cc: linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com, Catalin Marinas , Mark Rutland , linux-kernel@vger.kernel.org References: <20230801094052.750416-1-anshuman.khandual@arm.com> <20230801094052.750416-2-anshuman.khandual@arm.com> <20230801144936.GE26253@willie-the-truck> From: Anshuman Khandual In-Reply-To: <20230801144936.GE26253@willie-the-truck> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230801_194443_712150_4019E259 X-CRM114-Status: GOOD ( 27.61 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 8/1/23 20:19, Will Deacon wrote: > On Tue, Aug 01, 2023 at 03:10:49PM +0530, Anshuman Khandual wrote: >> Sanity checking all the GICC tables for same interrupt number, and ensuring >> a homogeneous ACPI based machine, could be used for other platform devices >> as well. Hence this refactors arm_spe_acpi_register_device() into a common >> helper arm_acpi_register_pmu_device(). >> >> Cc: Catalin Marinas >> Cc: Will Deacon >> Cc: Mark Rutland >> Cc: linux-arm-kernel@lists.infradead.org >> Cc: linux-kernel@vger.kernel.org >> Co-developed-by: Will Deacon >> Signed-off-by: Will Deacon >> Signed-off-by: Anshuman Khandual >> --- >> drivers/perf/arm_pmu_acpi.c | 110 +++++++++++++++++++++++------------- >> 1 file changed, 70 insertions(+), 40 deletions(-) >> >> diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c >> index 90815ad762eb..d9d5a7bbb92f 100644 >> --- a/drivers/perf/arm_pmu_acpi.c >> +++ b/drivers/perf/arm_pmu_acpi.c >> @@ -70,6 +70,68 @@ static void arm_pmu_acpi_unregister_irq(int cpu) >> } >> >> #if IS_ENABLED(CONFIG_ARM_SPE_PMU) >> +static int >> +arm_acpi_register_pmu_device(struct platform_device *pdev, u8 len, >> + u16 (*parse_gsi)(struct acpi_madt_generic_interrupt *)) >> +{ >> + int cpu, hetid, irq, ret; >> + bool matched = false; >> + u16 gsi = 0; >> + >> + /* >> + * Ensure that platform device must have IORESOURCE_IRQ >> + * resource to hold gsi interrupt. >> + */ >> + if (pdev->num_resources != 1) >> + return -ENXIO; >> + >> + if (pdev->resource[0].flags != IORESOURCE_IRQ) >> + return -ENXIO; >> + >> + /* >> + * Sanity check all the GICC tables for the same interrupt >> + * number. For now, only support homogeneous ACPI machines. >> + */ >> + for_each_possible_cpu(cpu) { >> + struct acpi_madt_generic_interrupt *gicc; >> + u16 this_gsi; >> + >> + gicc = acpi_cpu_get_madt_gicc(cpu); >> + if (gicc->header.length < len) >> + return matched ? -ENXIO : 0; >> + >> + this_gsi = parse_gsi(gicc); >> + if (!this_gsi) >> + return matched ? -ENXIO : 0; > > I think you can push this check into the conditional below... > >> + >> + if (!matched) { >> + hetid = find_acpi_cpu_topology_hetero_id(cpu); > > ... i.e. add a: > > if (!this_gsi) > return -ENXIO; > > here. > >> + gsi = this_gsi; >> + matched = true; > > And then, come to think of it, can we get rid of 'matched' altogether? > Since a gsi of 0 is treated as invalid, we could just check that instead, > no? So this becomes: > > > gicc = acpi_cpu_get_madt_gicc(cpu); > if (gicc->header.length < len) > return gsi ? -ENXIO : 0; > > this_hetid = find_acpi_cpu_topology_hetero_id(cpu); > this_gsi = parse_gsi(gicc); > if (!gsi) { > if (!this_gsi) > return -ENXIO; Unlike before, this returns -ENXIO on the very first instance itself without a match. Previously this returned 0 in such cases. But I guess that is okay. > gsi = this_gsi; > hetid = this_hetid; > } else if (hetid != this_hetid || gsi != this_gsi) { > pr_warn("ACPI: %s: must be homogeneous\n", pdev->name); > return -ENXIO; > } > > > What do you reckon? This makes sense, and the modified function will look something like arm_acpi_register_pmu_device(struct platform_device *pdev, u8 len, u16 (*parse_gsi)(struct acpi_madt_generic_interrupt *)) { int cpu, irq, ret; u16 gsi = 0; /* * Ensure that platform device must have IORESOURCE_IRQ * resource to hold gsi interrupt. */ if (pdev->num_resources != 1) return -ENXIO; if (pdev->resource[0].flags != IORESOURCE_IRQ) return -ENXIO; /* * Sanity check all the GICC tables for the same interrupt * number. For now, only support homogeneous ACPI machines. */ for_each_possible_cpu(cpu) { struct acpi_madt_generic_interrupt *gicc; int this_hetid, hetid; u16 this_gsi; gicc = acpi_cpu_get_madt_gicc(cpu); if (gicc->header.length < len) return gsi ? -ENXIO : 0; this_hetid = find_acpi_cpu_topology_hetero_id(cpu); this_gsi = parse_gsi(gicc); if (!gsi) { if (!this_gsi) return -ENXIO; hetid = this_hetid; gsi = this_gsi; } else if (hetid != this_hetid || gsi != this_gsi) { pr_warn("ACPI: %s: must be homogeneous\n", pdev->name); return -ENXIO; } } irq = acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH); if (irq < 0) { pr_warn("ACPI: %s Unable to register interrupt: %d\n", pdev->name, gsi); return -ENXIO; } pdev->resource[0].start = irq; ret = platform_device_register(pdev); if (ret < 0) { pr_warn("ACPI: %s: Unable to register device\n", pdev->name); acpi_unregister_gsi(gsi); } return ret; } _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel