From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754560AbbGXJpp (ORCPT ); Fri, 24 Jul 2015 05:45:45 -0400 Received: from eu-smtp-delivery-143.mimecast.com ([207.82.80.143]:54414 "EHLO eu-smtp-delivery-143.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754344AbbGXJou (ORCPT ); Fri, 24 Jul 2015 05:44:50 -0400 From: "Suzuki K. Poulose" To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, will.deacon@arm.com, mark.rutland@arm.com, edward.nevill@linaro.org, aph@redhat.com, linux-kernel@vger.kernel.org, "Suzuki K. Poulose" Subject: [RFC PATCH 09/10] arm64: Read system wide CPUID value Date: Fri, 24 Jul 2015 10:43:55 +0100 Message-Id: <1437731037-25795-10-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1437731037-25795-1-git-send-email-suzuki.poulose@arm.com> References: <1437731037-25795-1-git-send-email-suzuki.poulose@arm.com> X-OriginalArrivalTime: 24 Jul 2015 09:44:42.0839 (UTC) FILETIME=[5DFEE670:01D0C5F5] X-MC-Unique: So6tjK0LTsuoRd3eSMOMIg-9 Content-Type: text/plain; charset=WINDOWS-1252 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id t6O9k8jm027112 From: "Suzuki K. Poulose" Add an API for reading a safe CPUID value across the system Signed-off-by: Suzuki K. Poulose --- arch/arm64/include/asm/cpu.h | 2 ++ arch/arm64/kernel/cpuinfo.c | 9 +++++++++ 2 files changed, 11 insertions(+) diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h index cb25cb9..17a871d 100644 --- a/arch/arm64/include/asm/cpu.h +++ b/arch/arm64/include/asm/cpu.h @@ -177,6 +177,7 @@ struct arm64_ftr_reg { .ftr_bits = &((ftr_table)[0]), \ } +#define read_system_cpuid(id) read_system_reg(SYS_##id) /* * Records attributes of an individual CPU. */ @@ -226,4 +227,5 @@ static inline u64 arm64_ftr_value(struct arm64_ftr_bits *ftrp, u64 reg) return ((reg >> ftrp->shift) & ftrp->mask); } +u64 read_system_reg(enum sys_id id); #endif /* __ASM_CPU_H */ diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 9145eef..7d140f7 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -310,6 +310,15 @@ static struct arm64_ftr_reg* get_arm64_sys_reg(enum sys_id sys_id) return NULL; } +u64 read_system_reg(enum sys_id id) +{ + struct arm64_ftr_reg *regp = get_arm64_sys_reg(id); + + /* We shouldn't get a request for an unsupported register */ + BUG_ON(!regp); + return regp->sys_val; +} + static u64 arm64_ftr_set_value(struct arm64_ftr_bits *ftrp, u64 reg, u64 ftr_val) { u64 mask = ftrp->mask << ftrp->shift; -- 1.7.9.5