From patchwork Thu Nov 5 12:27:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11884279 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 7917DC388F7 for ; Thu, 5 Nov 2020 12:27:54 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 02A9220756 for ; Thu, 5 Nov 2020 12:27:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="zlyh3DsM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 02A9220756 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id: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=brxO4G3fuPq6i/Rj2vlVICLYT9rnQIJ/uOZgx2I3LQQ=; b=zlyh3DsMFaXf+7XuAl3Y2FSzLX tWriVrWJp4TPGYvqL0Mm8FG5whJmCVvXOoDu3jNSCanppi20zqvcwit6HLiQfkby1+u8qoJ9LNF+Z X4ou6BgrIz2VXhuDz0RhY/ignJyGxSD5/+ABE/xQql1i7c8qiraLT967/IRZd49TJ43N+UPCfJJL2 evXhgRMW48OogONgB9Ygw8dNI1gTO2MDTieno+iKllQ6HxROqE9uESp2Ue3GyizAEMfZn0Ng9n6QY Ls0HdDZ71bL79lRLfht3i2HCwYiLsx2ROt3R8JJFMXXlbhzxkuFuK2S+J/3p0mhxO5EpiTjKIpS6K /COF+2vg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaeMR-00014g-21; Thu, 05 Nov 2020 12:27:27 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaeMO-00013h-6B for linux-arm-kernel@lists.infradead.org; Thu, 05 Nov 2020 12:27:25 +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 9D0C0142F; Thu, 5 Nov 2020 04:27:22 -0800 (PST) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.198.32]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 32D4E3F719; Thu, 5 Nov 2020 04:27:21 -0800 (PST) From: Ionela Voinescu To: catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org Subject: [PATCH v3 1/3] arm64: wrap and generalise counter read functions Date: Thu, 5 Nov 2020 12:27:00 +0000 Message-Id: <20201105122702.13916-2-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201105122702.13916-1-ionela.voinescu@arm.com> References: <20201105122702.13916-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201105_072724_550026_D7AA3666 X-CRM114-Status: GOOD ( 14.68 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: souvik.chakravarty@arm.com, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org, valentin.schneider@arm.com, ionela.voinescu@arm.com, morten.rasmussen@arm.com, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In preparation for other uses of Activity Monitors (AMU) cycle counters, place counter read functionality in generic functions that can reused: read_corecnt() and read_constcnt(). As a result, implement update_freq_counters_refs() to replace init_cpu_freq_invariance_counters() and both initialise and update the per-cpu reference variables. Signed-off-by: Ionela Voinescu Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/include/asm/cpufeature.h | 5 ++++ arch/arm64/include/asm/topology.h | 4 +++- arch/arm64/kernel/cpufeature.c | 5 +--- arch/arm64/kernel/topology.c | 36 +++++++++++++++++++---------- 4 files changed, 33 insertions(+), 17 deletions(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 97244d4feca9..751bd9d3376b 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -765,6 +765,11 @@ static inline bool cpu_has_hw_af(void) #ifdef CONFIG_ARM64_AMU_EXTN /* Check whether the cpu supports the Activity Monitors Unit (AMU) */ extern bool cpu_has_amu_feat(int cpu); +#else +static inline bool cpu_has_amu_feat(int cpu) +{ + return false; +} #endif static inline unsigned int get_vmid_bits(u64 mmfr1) diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h index 11a465243f66..3b8dca4eb08d 100644 --- a/arch/arm64/include/asm/topology.h +++ b/arch/arm64/include/asm/topology.h @@ -16,12 +16,14 @@ int pcibus_to_node(struct pci_bus *bus); #include +void update_freq_counters_refs(void); +void topology_scale_freq_tick(void); + #ifdef CONFIG_ARM64_AMU_EXTN /* * Replace task scheduler's default counter-based * frequency-invariance scale factor setting. */ -void topology_scale_freq_tick(void); #define arch_scale_freq_tick topology_scale_freq_tick #endif /* CONFIG_ARM64_AMU_EXTN */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index dcc165b3fc04..1142970e985b 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1526,16 +1526,13 @@ bool cpu_has_amu_feat(int cpu) return cpumask_test_cpu(cpu, &amu_cpus); } -/* Initialize the use of AMU counters for frequency invariance */ -extern void init_cpu_freq_invariance_counters(void); - 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 Unit (AMU)\n", smp_processor_id()); cpumask_set_cpu(smp_processor_id(), &amu_cpus); - init_cpu_freq_invariance_counters(); + update_freq_counters_refs(); } } diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 543c67cae02f..db03c440e157 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -123,23 +123,33 @@ int __init parse_acpi_topology(void) } #endif -#ifdef CONFIG_ARM64_AMU_EXTN +#define COUNTER_READ_STORE(NAME, VAL) \ +static inline u64 read_##NAME(void) \ +{ \ + return VAL; \ +} \ +static inline void store_##NAME(void *val) \ +{ \ + *(u64 *)val = read_##NAME(); \ +} -#undef pr_fmt -#define pr_fmt(fmt) "AMU: " fmt +#ifdef CONFIG_ARM64_AMU_EXTN +COUNTER_READ_STORE(corecnt, read_sysreg_s(SYS_AMEVCNTR0_CORE_EL0)); +COUNTER_READ_STORE(constcnt, read_sysreg_s(SYS_AMEVCNTR0_CONST_EL0)); +#else +COUNTER_READ_STORE(corecnt, 0); +COUNTER_READ_STORE(constcnt, 0); +#endif static DEFINE_PER_CPU_READ_MOSTLY(unsigned long, arch_max_freq_scale); static DEFINE_PER_CPU(u64, arch_const_cycles_prev); static DEFINE_PER_CPU(u64, arch_core_cycles_prev); static cpumask_var_t amu_fie_cpus; -/* Initialize counter reference per-cpu variables for the current CPU */ -void init_cpu_freq_invariance_counters(void) +void update_freq_counters_refs(void) { - this_cpu_write(arch_core_cycles_prev, - read_sysreg_s(SYS_AMEVCNTR0_CORE_EL0)); - this_cpu_write(arch_const_cycles_prev, - read_sysreg_s(SYS_AMEVCNTR0_CONST_EL0)); + this_cpu_write(arch_core_cycles_prev, read_corecnt()); + this_cpu_write(arch_const_cycles_prev, read_constcnt()); } static int validate_cpu_freq_invariance_counters(int cpu) @@ -280,11 +290,14 @@ void topology_scale_freq_tick(void) if (!cpumask_test_cpu(cpu, amu_fie_cpus)) return; - const_cnt = read_sysreg_s(SYS_AMEVCNTR0_CONST_EL0); - core_cnt = read_sysreg_s(SYS_AMEVCNTR0_CORE_EL0); prev_const_cnt = this_cpu_read(arch_const_cycles_prev); prev_core_cnt = this_cpu_read(arch_core_cycles_prev); + update_freq_counters_refs(); + + const_cnt = this_cpu_read(arch_const_cycles_prev); + core_cnt = this_cpu_read(arch_core_cycles_prev); + if (unlikely(core_cnt <= prev_core_cnt || const_cnt <= prev_const_cnt)) goto store_and_exit; @@ -309,4 +322,3 @@ void topology_scale_freq_tick(void) this_cpu_write(arch_core_cycles_prev, core_cnt); this_cpu_write(arch_const_cycles_prev, const_cnt); } -#endif /* CONFIG_ARM64_AMU_EXTN */ From patchwork Thu Nov 5 12:27:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11884283 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 93296C00A89 for ; Thu, 5 Nov 2020 12:28:00 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 21A2020756 for ; 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Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaeMa-00017D-SG; Thu, 05 Nov 2020 12:27:36 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kaeMQ-00014M-8z for linux-arm-kernel@lists.infradead.org; Thu, 05 Nov 2020 12:27:27 +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 7180A14BF; Thu, 5 Nov 2020 04:27:25 -0800 (PST) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.198.32]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 05E7F3F719; Thu, 5 Nov 2020 04:27:23 -0800 (PST) From: Ionela Voinescu To: catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org Subject: [PATCH v3 2/3] arm64: split counter validation function Date: Thu, 5 Nov 2020 12:27:01 +0000 Message-Id: <20201105122702.13916-3-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201105122702.13916-1-ionela.voinescu@arm.com> References: <20201105122702.13916-1-ionela.voinescu@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201105_072726_438571_A8D5E192 X-CRM114-Status: GOOD ( 16.61 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: souvik.chakravarty@arm.com, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org, valentin.schneider@arm.com, ionela.voinescu@arm.com, morten.rasmussen@arm.com, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In order for the counter validation function to be reused, split validate_cpu_freq_invariance_counters() into: - freq_counters_valid(cpu) - check cpu for valid cycle counters - freq_inv_set_max_ratio(int cpu, u64 max_rate, u64 ref_rate) - generic function that sets the normalization ratio used by topology_scale_freq_tick() Signed-off-by: Ionela Voinescu Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/kernel/topology.c | 44 +++++++++++++++++++++--------------- 1 file changed, 26 insertions(+), 18 deletions(-) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index db03c440e157..764fdb0f947b 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -152,45 +152,49 @@ void update_freq_counters_refs(void) this_cpu_write(arch_const_cycles_prev, read_constcnt()); } -static int validate_cpu_freq_invariance_counters(int cpu) +static inline bool freq_counters_valid(int cpu) { - u64 max_freq_hz, ratio; - if (!cpu_has_amu_feat(cpu)) { pr_debug("CPU%d: counters are not supported.\n", cpu); - return -EINVAL; + return false; } if (unlikely(!per_cpu(arch_const_cycles_prev, cpu) || !per_cpu(arch_core_cycles_prev, cpu))) { pr_debug("CPU%d: cycle counters are not enabled.\n", cpu); - return -EINVAL; + return false; } - /* Convert maximum frequency from KHz to Hz and validate */ - max_freq_hz = cpufreq_get_hw_max_freq(cpu) * 1000; - if (unlikely(!max_freq_hz)) { - pr_debug("CPU%d: invalid maximum frequency.\n", cpu); + return true; +} + +static int freq_inv_set_max_ratio(int cpu, u64 max_rate, u64 ref_rate) +{ + u64 ratio; + + if (unlikely(!max_rate || !ref_rate)) { + pr_debug("CPU%d: invalid maximum or reference frequency.\n", + cpu); return -EINVAL; } /* * Pre-compute the fixed ratio between the frequency of the constant - * counter and the maximum frequency of the CPU. + * reference counter and the maximum frequency of the CPU. * - * const_freq - * arch_max_freq_scale = ---------------- * SCHED_CAPACITY_SCALE² - * cpuinfo_max_freq + * ref_rate + * arch_max_freq_scale = ---------- * SCHED_CAPACITY_SCALE² + * max_rate * * We use a factor of 2 * SCHED_CAPACITY_SHIFT -> SCHED_CAPACITY_SCALE² * in order to ensure a good resolution for arch_max_freq_scale for - * very low arch timer frequencies (down to the KHz range which should + * very low reference frequencies (down to the KHz range which should * be unlikely). */ - ratio = (u64)arch_timer_get_rate() << (2 * SCHED_CAPACITY_SHIFT); - ratio = div64_u64(ratio, max_freq_hz); + ratio = ref_rate << (2 * SCHED_CAPACITY_SHIFT); + ratio = div64_u64(ratio, max_rate); if (!ratio) { - WARN_ONCE(1, "System timer frequency too low.\n"); + WARN_ONCE(1, "Reference frequency too low.\n"); return -EINVAL; } @@ -237,8 +241,12 @@ static int __init init_amu_fie(void) } for_each_present_cpu(cpu) { - if (validate_cpu_freq_invariance_counters(cpu)) + if (!freq_counters_valid(cpu) || + freq_inv_set_max_ratio(cpu, + cpufreq_get_hw_max_freq(cpu) * 1000, + arch_timer_get_rate())) continue; + cpumask_set_cpu(cpu, valid_cpus); have_policy |= enable_policy_freq_counters(cpu, valid_cpus); } From patchwork Thu Nov 5 12:27:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11884281 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 D803FC00A89 for ; 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Thu, 5 Nov 2020 04:27:27 -0800 (PST) From: Ionela Voinescu To: catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org Subject: [PATCH v3 3/3] arm64: implement CPPC FFH support using AMUs Date: Thu, 5 Nov 2020 12:27:02 +0000 Message-Id: <20201105122702.13916-4-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201105122702.13916-1-ionela.voinescu@arm.com> References: <20201105122702.13916-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201105_072730_908240_1A1473D6 X-CRM114-Status: GOOD ( 19.20 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: souvik.chakravarty@arm.com, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org, valentin.schneider@arm.com, ionela.voinescu@arm.com, morten.rasmussen@arm.com, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org If Activity Monitors (AMUs) are present, two of the counters can be used to implement support for CPPC's (Collaborative Processor Performance Control) delivered and reference performance monitoring functionality using FFH (Functional Fixed Hardware). Given that counters for a certain CPU can only be read from that CPU, while FFH operations can be called from any CPU for any of the CPUs, use smp_call_function_single() to provide the requested values. Therefore, depending on the register addresses, the following values are returned: - 0x0 (DeliveredPerformanceCounterRegister): AMU core counter - 0x1 (ReferencePerformanceCounterRegister): AMU constant counter The use of Activity Monitors is hidden behind the generic {read,store}_{corecnt,constcnt}() functions. Read functionality for these two registers represents the only current FFH support for CPPC. Read operations for other register values or write operation for all registers are unsupported. Therefore, keep CPPC's FFH unsupported if no CPUs have valid AMU frequency counters. For this purpose, the get_cpu_with_amu_feat() is introduced. Signed-off-by: Ionela Voinescu Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/include/asm/cpufeature.h | 3 ++ arch/arm64/kernel/cpufeature.c | 10 ++++++ arch/arm64/kernel/topology.c | 54 +++++++++++++++++++++++++++++ 3 files changed, 67 insertions(+) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 751bd9d3376b..f5b44ac354dc 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -772,6 +772,9 @@ static inline bool cpu_has_amu_feat(int cpu) } #endif +/* Get a cpu that supports the Activity Monitors Unit (AMU) */ +extern int get_cpu_with_amu_feat(void); + static inline unsigned int get_vmid_bits(u64 mmfr1) { int vmid_bits; diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 1142970e985b..6b08ae74ad0a 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1526,6 +1526,11 @@ bool cpu_has_amu_feat(int cpu) return cpumask_test_cpu(cpu, &amu_cpus); } +int get_cpu_with_amu_feat(void) +{ + return cpumask_any(&amu_cpus); +} + static void cpu_amu_enable(struct arm64_cpu_capabilities const *cap) { if (has_cpuid_feature(cap, SCOPE_LOCAL_CPU)) { @@ -1554,6 +1559,11 @@ static bool has_amu(const struct arm64_cpu_capabilities *cap, return true; } +#else +int get_cpu_with_amu_feat(void) +{ + return nr_cpu_ids; +} #endif #ifdef CONFIG_ARM64_VHE diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 764fdb0f947b..7d25087deaa5 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -154,6 +154,9 @@ void update_freq_counters_refs(void) static inline bool freq_counters_valid(int cpu) { + if ((cpu >= nr_cpu_ids) || !cpumask_test_cpu(cpu, cpu_present_mask)) + return false; + if (!cpu_has_amu_feat(cpu)) { pr_debug("CPU%d: counters are not supported.\n", cpu); return false; @@ -330,3 +333,54 @@ void topology_scale_freq_tick(void) this_cpu_write(arch_core_cycles_prev, core_cnt); this_cpu_write(arch_const_cycles_prev, const_cnt); } + +#ifdef CONFIG_ACPI_CPPC_LIB +#include + +static inline +int counters_read_on_cpu(int cpu, smp_call_func_t func, u64 *val) +{ + if (!cpu_has_amu_feat(cpu)) + return -EOPNOTSUPP; + + smp_call_function_single(cpu, func, val, 1); + + return 0; +} + +/* + * Refer to drivers/acpi/cppc_acpi.c for the description of the functions + * below. + */ +bool cpc_ffh_supported(void) +{ + return freq_counters_valid(get_cpu_with_amu_feat()); +} + +int cpc_read_ffh(int cpu, struct cpc_reg *reg, u64 *val) +{ + int ret = -EOPNOTSUPP; + + switch ((u64)reg->address) { + case 0x0: + ret = counters_read_on_cpu(cpu, store_corecnt, val); + break; + case 0x1: + ret = counters_read_on_cpu(cpu, store_constcnt, val); + break; + } + + if (!ret) { + *val &= GENMASK_ULL(reg->bit_offset + reg->bit_width - 1, + reg->bit_offset); + *val >>= reg->bit_offset; + } + + return ret; +} + +int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_ACPI_CPPC_LIB */