From patchwork Mon Apr 1 10:45:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10879709 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 61DC215AC for ; Mon, 1 Apr 2019 10:46:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4691B28414 for ; Mon, 1 Apr 2019 10:46:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3A71B2880B; Mon, 1 Apr 2019 10:46:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B168728414 for ; Mon, 1 Apr 2019 10:46:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=SarhXH6u4SeUH2hdTrOwGbh8F+fDSDXo2ADB4ecY4c4=; b=Sh/hohDozR/m2v +TFea0AI9J77wX/zK4qm7FPLeiLmsZyNgvd4m2gZZ+nZdI4SK5pM/AipRlU0lRm3qIE2N2V8wIRkN vf1TRmN0ZFPtBP6Zd63GT4db8oOeEG7fkrdMK8mLne7JaiSpn283P9+i/+L+Im9fWbtZi2cNhh0TS 22go3m2pz4ta0yU2IcZhI6RtQca7A+E0Hrlhazz3MT/+KuoiMxLdcU3S21/lF/aKYm0FOhOm70fX4 GTKxIrIjLGLuK3X03ql8EJyFGzWhCJJ/OhMVuPAm9ChHQ0r7o210dJNKJ8P894krXLABegsTBUUos W9F/H1ffFJJ1u4O7I+tA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hAuS9-0002l5-HW; Mon, 01 Apr 2019 10:46:09 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hAuRZ-0001vk-7J for linux-arm-kernel@lists.infradead.org; Mon, 01 Apr 2019 10:45:44 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9BE8A1684; Mon, 1 Apr 2019 03:45:32 -0700 (PDT) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.20]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id AD7083F557; Mon, 1 Apr 2019 03:45:30 -0700 (PDT) From: Andrew Murray To: Catalin Marinas , Will Deacon Subject: [PATCH v3 3/7] arm64: HWCAP: encapsulate elf_hwcap Date: Mon, 1 Apr 2019 11:45:11 +0100 Message-Id: <20190401104515.39775-4-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401104515.39775-1-andrew.murray@arm.com> References: <20190401104515.39775-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190401_034533_725046_5A2CA8F3 X-CRM114-Status: GOOD ( 13.64 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , libc-alpha@sourceware.org, Szabolcs Nagy , linux-api@vger.kernel.org, Phil Blundell , dave.martin@arm.com, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The introduction of AT_HWCAP2 introduced accessors which ensure that hwcap features are set and tested appropriately. Let's now mandate access to elf_hwcap via these accessors by making elf_hwcap static within cpufeature.c. Signed-off-by: Andrew Murray --- arch/arm64/include/asm/cpufeature.h | 15 ++++---------- arch/arm64/include/asm/hwcap.h | 7 +++---- arch/arm64/kernel/cpufeature.c | 32 +++++++++++++++++++++++++++-- 3 files changed, 37 insertions(+), 17 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index f06e1da1d678..4c766f831de6 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -392,19 +392,12 @@ extern DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE); for_each_set_bit(cap, cpu_hwcaps, ARM64_NCAPS) bool this_cpu_has_cap(unsigned int cap); +void cpu_set_feature(unsigned int num); +bool cpu_have_feature(unsigned int num); +unsigned long cpu_get_elf_hwcap(void); +unsigned long cpu_get_elf_hwcap2(void); -static inline void cpu_set_feature(unsigned int num) -{ - WARN_ON(num >= MAX_CPU_FEATURES); - elf_hwcap |= BIT(num); -} #define cpu_set_named_feature(name) cpu_set_feature(cpu_feature(name)) - -static inline bool cpu_have_feature(unsigned int num) -{ - WARN_ON(num >= MAX_CPU_FEATURES); - return elf_hwcap & BIT(num); -} #define cpu_have_named_feature(name) cpu_have_feature(cpu_feature(name)) /* System capability check for constant caps */ diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h index d21fe3314d90..de9a66672ba7 100644 --- a/arch/arm64/include/asm/hwcap.h +++ b/arch/arm64/include/asm/hwcap.h @@ -17,6 +17,7 @@ #define __ASM_HWCAP_H #include +#include #define COMPAT_HWCAP_HALF (1 << 1) #define COMPAT_HWCAP_THUMB (1 << 2) @@ -84,14 +85,13 @@ #define KERNEL_HWCAP_DCPODP (ilog2(HWCAP2_DCPODP) + 32) #ifndef __ASSEMBLY__ -#include /* * This yields a mask that user programs can use to figure out what * instruction set this cpu supports. */ -#define ELF_HWCAP lower_32_bits(elf_hwcap) -#define ELF_HWCAP2 upper_32_bits(elf_hwcap) +#define ELF_HWCAP cpu_get_elf_hwcap() +#define ELF_HWCAP2 cpu_get_elf_hwcap2() #ifdef CONFIG_COMPAT #define COMPAT_ELF_HWCAP (compat_elf_hwcap) @@ -107,6 +107,5 @@ enum { #endif }; -extern unsigned long elf_hwcap; #endif #endif diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 986ceeacd19f..84ca52fa75e5 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -35,8 +35,7 @@ #include #include -unsigned long elf_hwcap __read_mostly; -EXPORT_SYMBOL_GPL(elf_hwcap); +static unsigned long elf_hwcap __read_mostly; #ifdef CONFIG_COMPAT #define COMPAT_ELF_HWCAP_DEFAULT \ @@ -1947,6 +1946,35 @@ bool this_cpu_has_cap(unsigned int n) return false; } +void cpu_set_feature(unsigned int num) +{ + WARN_ON(num >= MAX_CPU_FEATURES); + elf_hwcap |= BIT(num); +} +EXPORT_SYMBOL_GPL(cpu_set_feature); + +bool cpu_have_feature(unsigned int num) +{ + WARN_ON(num >= MAX_CPU_FEATURES); + return elf_hwcap & BIT(num); +} +EXPORT_SYMBOL_GPL(cpu_have_feature); + +unsigned long cpu_get_elf_hwcap(void) +{ + /* + * We currently only populate the first 32 bits of AT_HWCAP. Please + * note that for userspace compatibility we guarantee that bit 62 + * will always be returned as 0. + */ + return lower_32_bits(elf_hwcap); +} + +unsigned long cpu_get_elf_hwcap2(void) +{ + return upper_32_bits(elf_hwcap); +} + static void __init setup_system_capabilities(void) { /*