From patchwork Wed Apr 3 10:56:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10883441 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 B56C7922 for ; Wed, 3 Apr 2019 10:57:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9A5F4289C7 for ; Wed, 3 Apr 2019 10:57:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8E75D289D1; Wed, 3 Apr 2019 10:57:11 +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 20FD5289DA for ; Wed, 3 Apr 2019 10:57:11 +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=9hm1sTtBV8A7ksK79hATW0dwkJ7z7sWFD/mdm6E+HYg=; b=UPKtqbRrTKElrP r1RuDiokDIOorXcvInA+vlclqR1UwRJCQmUkoT0qVFp78DMb3Ho/UYvPJtcRbPH9Rfh20a7/E3JIh 4YtMs45NJy4vWWm1tIB/rvyc6ypYfHoXL5bGzZ7KMtOTcjlhjvYr8KemBKkdp84OVlM9o7rT+jcct Eju3al6wuB53SPqZWhYXa7fKl5toUmWicKL97T+qEw10OaycGbo2pc1ZkPpmteZPFi8JpnZivioNW yVFwd6Y8gxVKoAaM7w5immu1Jv0Fhlpd5xSQeGYjooBqxsrJi3ETnxAnbE5ceQ76oEPgGHvZeXmce 6eInhFZTABeaiHFhaL7g==; 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 1hBdZs-0006aU-Uc; Wed, 03 Apr 2019 10:57:08 +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 1hBdZS-00065J-IC for linux-arm-kernel@lists.infradead.org; Wed, 03 Apr 2019 10:57:05 +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 9E11815AD; Wed, 3 Apr 2019 03:56:41 -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 886943F59C; Wed, 3 Apr 2019 03:56:39 -0700 (PDT) From: Andrew Murray To: Catalin Marinas , Will Deacon Subject: [PATCH v4 2/6] arm64: HWCAP: encapsulate elf_hwcap Date: Wed, 3 Apr 2019 11:56:24 +0100 Message-Id: <20190403105628.39798-3-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190403105628.39798-1-andrew.murray@arm.com> References: <20190403105628.39798-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190403_035642_634397_D03BD710 X-CRM114-Status: GOOD ( 13.26 ) 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, Suzuki K Poulose , 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 Reviewed-by: Dave Martin Reviewed-by: Suzuki K Poulose --- arch/arm64/include/asm/cpufeature.h | 15 ++++--------- arch/arm64/include/asm/hwcap.h | 7 +++--- arch/arm64/kernel/cpufeature.c | 33 +++++++++++++++++++++++++++-- 3 files changed, 38 insertions(+), 17 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 347c17046668..a3f028f82def 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 1f38a2740f7a..509ee0d2fa0f 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) @@ -86,14 +87,13 @@ #define __khwcap2_feature(x) (ilog2(HWCAP2_ ## x) + 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) @@ -109,6 +109,5 @@ 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..a655d1bb1186 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -35,8 +35,8 @@ #include #include -unsigned long elf_hwcap __read_mostly; -EXPORT_SYMBOL_GPL(elf_hwcap); +/* Kernel representation of AT_HWCAP and AT_HWCAP2 */ +static unsigned long elf_hwcap __read_mostly; #ifdef CONFIG_COMPAT #define COMPAT_ELF_HWCAP_DEFAULT \ @@ -1947,6 +1947,35 @@ 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 bits 62 + * and 63 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) { /*