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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38CB7C4CECD for ; Tue, 17 Sep 2019 13:43:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 026CE2189D for ; Tue, 17 Sep 2019 13:43:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728744AbfIQNnW (ORCPT ); Tue, 17 Sep 2019 09:43:22 -0400 Received: from foss.arm.com ([217.140.110.172]:56166 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725902AbfIQNnW (ORCPT ); Tue, 17 Sep 2019 09:43:22 -0400 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 E1B0D28; Tue, 17 Sep 2019 06:43:20 -0700 (PDT) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.199.68]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8E1D43F575; Tue, 17 Sep 2019 06:43:19 -0700 (PDT) From: Ionela Voinescu To: catalin.marinas@arm.com, will@kernel.org, maz@kernel.org, corbet@lwn.net Cc: linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Ionela Voinescu , Suzuki K Poulose , Mark Rutland Subject: [PATCH 1/4] arm64: add support for the AMU extension v1 Date: Tue, 17 Sep 2019 14:42:25 +0100 Message-Id: <20190917134228.5369-2-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190917134228.5369-1-ionela.voinescu@arm.com> References: <20190917134228.5369-1-ionela.voinescu@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The activity monitors extension is an optional extension introduced by the ARMv8.4 CPU architecture. This implements basic support for version 1 of the activity monitors architecture, AMUv1. This support includes: - Extension detection on each CPU (boot, secondary, hotplugged) - Register interface for AMU aarch64 registers - (while here) create defines for ID_PFR0_EL1 fields when adding the AMU field information. Signed-off-by: Ionela Voinescu Cc: Catalin Marinas Cc: Will Deacon Cc: Suzuki K Poulose Cc: Marc Zyngier Cc: Mark Rutland --- arch/arm64/Kconfig | 27 ++++++++++++ arch/arm64/include/asm/cpucaps.h | 3 +- arch/arm64/include/asm/sysreg.h | 44 ++++++++++++++++++++ arch/arm64/kernel/cpufeature.c | 71 ++++++++++++++++++++++++++++++-- 4 files changed, 140 insertions(+), 5 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6b6362b83004..3bf7972d43c7 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1410,6 +1410,33 @@ config ARM64_PTR_AUTH endmenu +menu "ARMv8.4 architectural features" + +config ARM64_AMU_EXTN + bool "Enable support for the Activity Monitors Unit CPU extension" + default y + help + The activity monitors extension is an optional extension introduced + by the ARMv8.4 CPU architecture. This enables support for version 1 + of the activity monitors architecture, AMUv1. + + To enable the use of this extension on CPUs that implement it, say Y. + + Note that for architectural reasons, firmware _must_ implement AMU + support when running on CPUs that present the activity monitors + extension. The required support is present in: + * Version 1.5 and later of the ARM Trusted Firmware + + For kernels that have this configuration enabled but boot with broken + firmware, you may need to say N here until the firmware is fixed. + Otherwise you may experience firmware panics or lockups when + accessing the counter registers. Even if you are not observing these + symptoms, the values returned by the register reads might not + correctly reflect reality. Most commonly, the value read will be 0, + indicating that the counter is not enabled. + +endmenu + config ARM64_SVE bool "ARM Scalable Vector Extension support" default y diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index f19fe4b9acc4..7f12ad4f69ad 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -52,7 +52,8 @@ #define ARM64_HAS_IRQ_PRIO_MASKING 42 #define ARM64_HAS_DCPODP 43 #define ARM64_WORKAROUND_1463225 44 +#define ARM64_HAS_AMU_EXTN 45 -#define ARM64_NCAPS 45 +#define ARM64_NCAPS 46 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 972d196c7714..f090a86a376d 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -382,6 +382,42 @@ #define SYS_TPIDR_EL0 sys_reg(3, 3, 13, 0, 2) #define SYS_TPIDRRO_EL0 sys_reg(3, 3, 13, 0, 3) +/* Definitions for system register interface to AMU for ARMv8.4 onwards */ +#define SYS_AM_EL0(crm, op2) sys_reg(3, 3, 13, crm, op2) +#define SYS_AMCR_EL0 SYS_AM_EL0(2, 0) +#define SYS_AMCFGR_EL0 SYS_AM_EL0(2, 1) +#define SYS_AMCGCR_EL0 SYS_AM_EL0(2, 2) +#define SYS_AMUSERENR_EL0 SYS_AM_EL0(2, 3) +#define SYS_AMCNTENCLR0_EL0 SYS_AM_EL0(2, 4) +#define SYS_AMCNTENSET0_EL0 SYS_AM_EL0(2, 5) +#define SYS_AMCNTENCLR1_EL0 SYS_AM_EL0(3, 0) +#define SYS_AMCNTENSET1_EL0 SYS_AM_EL0(3, 1) + +/* + * Group 0 of activity monitors (architected): + * op0 CRn op1 op2 CRm + * Counter: 11 1101 011 n<2:0> 010:n<3> + * Type: 11 1101 011 n<2:0> 011:n<3> + * n: 0-3 + * + * Group 1 of activity monitors (auxiliary): + * op0 CRn op1 op2 CRm + * Counter: 11 1101 011 n<2:0> 110:n<3> + * Type: 11 1101 011 n<2:0> 111:n<3> + * n: 0-15 + */ + +#define SYS_AMEVCNTR0_EL0(n) SYS_AM_EL0(4 + ((n) >> 3), (n) & 0x7) +#define SYS_AMEVTYPE0_EL0(n) SYS_AM_EL0(6 + ((n) >> 3), (n) & 0x7) +#define SYS_AMEVCNTR1_EL0(n) SYS_AM_EL0(12 + ((n) >> 3), (n) & 0x7) +#define SYS_AMEVTYPE1_EL0(n) SYS_AM_EL0(14 + ((n) >> 3), (n) & 0x7) + +/* V1: Fixed (architecturally defined) activity monitors */ +#define SYS_AMEVCNTR0_CORE_EL0 SYS_AMEVCNTR0_EL0(0) +#define SYS_AMEVCNTR0_CONST_EL0 SYS_AMEVCNTR0_EL0(1) +#define SYS_AMEVCNTR0_INST_RET_EL0 SYS_AMEVCNTR0_EL0(2) +#define SYS_AMEVCNTR0_MEM_STALL SYS_AMEVCNTR0_EL0(3) + #define SYS_CNTFRQ_EL0 sys_reg(3, 3, 14, 0, 0) #define SYS_CNTP_TVAL_EL0 sys_reg(3, 3, 14, 2, 0) @@ -577,6 +613,7 @@ #define ID_AA64PFR0_CSV3_SHIFT 60 #define ID_AA64PFR0_CSV2_SHIFT 56 #define ID_AA64PFR0_DIT_SHIFT 48 +#define ID_AA64PFR0_AMU_SHIFT 44 #define ID_AA64PFR0_SVE_SHIFT 32 #define ID_AA64PFR0_RAS_SHIFT 28 #define ID_AA64PFR0_GIC_SHIFT 24 @@ -587,6 +624,7 @@ #define ID_AA64PFR0_EL1_SHIFT 4 #define ID_AA64PFR0_EL0_SHIFT 0 +#define ID_AA64PFR0_AMU 0x1 #define ID_AA64PFR0_SVE 0x1 #define ID_AA64PFR0_RAS_V1 0x1 #define ID_AA64PFR0_FP_NI 0xf @@ -709,6 +747,12 @@ #define ID_AA64MMFR0_TGRAN16_NI 0x0 #define ID_AA64MMFR0_TGRAN16_SUPPORTED 0x1 +#define ID_PFR0_AMU_SHIFT 20 +#define ID_PFR0_STATE3_SHIFT 12 +#define ID_PFR0_STATE2_SHIFT 8 +#define ID_PFR0_STATE1_SHIFT 4 +#define ID_PFR0_STATE0_SHIFT 0 + #if defined(CONFIG_ARM64_4K_PAGES) #define ID_AA64MMFR0_TGRAN_SHIFT ID_AA64MMFR0_TGRAN4_SHIFT #define ID_AA64MMFR0_TGRAN_SUPPORTED ID_AA64MMFR0_TGRAN4_SUPPORTED diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 9323bcc40a58..cce86c6a5d00 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -155,6 +155,7 @@ static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_DIT_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_AMU_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SVE), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_SVE_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_RAS_SHIFT, 4, 0), @@ -308,10 +309,11 @@ static const struct arm64_ftr_bits ftr_id_mmfr4[] = { }; static const struct arm64_ftr_bits ftr_id_pfr0[] = { - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), /* State3 */ - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0), /* State2 */ - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* State1 */ - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 0, 4, 0), /* State0 */ + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_AMU_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE3_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE2_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE1_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_STATE0_SHIFT, 4, 0), ARM64_FTR_END, }; @@ -1143,6 +1145,49 @@ static bool has_hw_dbm(const struct arm64_cpu_capabilities *cap, #endif +#ifdef CONFIG_ARM64_AMU_EXTN + +/* + * This per cpu variable only signals that the CPU implementation supports the + * AMU but does not provide information regarding all the events that it + * supports. + * When this amu_feat per CPU variable is true, the user of this feature can + * only rely on the presence of the 4 fixed counters. But this does not + * guarantee that the counters are enabled or access to these counters is + * provided by code executed at higher exception levels. + */ +DEFINE_PER_CPU(bool, amu_feat) = false; + +static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap) +{ + if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) { + pr_info("detected CPU%d: Activity Monitors extension\n", + smp_processor_id()); + this_cpu_write(amu_feat, true); + } +} + +static bool has_amu(const struct arm64_cpu_capabilities *cap, + int __unused) +{ + /* + * The AMU extension is a non-conflicting feature: the kernel can + * safely run a mix of CPUs with and without support for the + * activity monitors extension. + * Therefore, unconditionally enable the capability to allow + * any late CPU to use the feature. + * + * With this feature unconditionally enabled, the cpu_enable + * function will be called for all CPUs that match the criteria, + * including secondary and hotplugged, marking this feature as + * present on that respective CPU. The enable function will also + * print a detection message. + */ + + return true; +} +#endif + #ifdef CONFIG_ARM64_VHE static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused) { @@ -1412,6 +1457,24 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .cpu_enable = cpu_clear_disr, }, #endif /* CONFIG_ARM64_RAS_EXTN */ +#ifdef CONFIG_ARM64_AMU_EXTN + { + /* + * The feature is enabled by default if CONFIG_ARM64_AMU_EXTN=y. + * Therefore, don't provide .desc as we don't want the detection + * message to be shown until at least one CPU is detected to + * support the feature. + */ + .capability = ARM64_HAS_AMU_EXTN, + .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE, + .matches = has_amu, + .sys_reg = SYS_ID_AA64PFR0_EL1, + .sign = FTR_UNSIGNED, + .field_pos = ID_AA64PFR0_AMU_SHIFT, + .min_field_value = ID_AA64PFR0_AMU, + .cpu_enable = cpu_amu_enable, + }, +#endif /* CONFIG_ARM64_AMU_EXTN */ { .desc = "Data cache clean to the PoU not required for I/D coherence", .capability = ARM64_HAS_CACHE_IDC, -- 2.17.1