From patchwork Thu Feb 29 16:25:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vanshidhar Konda X-Patchwork-Id: 13577362 Received: from NAM02-DM3-obe.outbound.protection.outlook.com (mail-dm3nam02on2131.outbound.protection.outlook.com [40.107.95.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D0A6870AE6; Thu, 29 Feb 2024 16:25:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.95.131 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709223938; cv=fail; b=ji8wdzeZuSljacbrTzeyQGbbfvj9Z4kw92vyCumwERdtltwqLK9/LsP+Z0Xms2c0ieEp5mv+Rrb/HT/qh6sLmBEC4FtsIzafHv31/cV4/YzvQUEIP6pcO2+obwFI5w3JSORl7jioE7vNFeLTtzgRUOhJIukzzJmq57s2l28m+xE= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709223938; c=relaxed/simple; bh=akCzDfabACtg2Ea9LgKZ9QnqG4lJ+HMdiMr6ggTo/YA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=bxdQf8vNzM2ai5qOGDNdSy+t2lOJhmbE36s4ARl9wbp+3Y35r7NGEOwkV8VYPCUbFEC+zRPHQNmF1e7O/yd1hVjsFBr7Atn87+JZEe9jz21dDXqxLmvAyqkbSmqu1pjmb/zFNEcJFt6uSzxD7buG8bfwh3/tYCcLttjPUeUtChQ= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=os.amperecomputing.com; spf=pass smtp.mailfrom=os.amperecomputing.com; dkim=pass (1024-bit key) header.d=os.amperecomputing.com header.i=@os.amperecomputing.com header.b=WjllIipT; arc=fail smtp.client-ip=40.107.95.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=os.amperecomputing.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=os.amperecomputing.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=os.amperecomputing.com header.i=@os.amperecomputing.com header.b="WjllIipT" ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=TUITIbcW3t4Kj/OxamBy2thdw6rr+u4xd2qqvYLKQpq46KIiwM6aRFzcnjEjAuzTyncT6sCsF7Gs4NiOPVM2pnOBIm2Cl+sld55ZedzFtxZj0b8VqymDA9BVIIcJJVtnnE5md5fVXQCdRFw4Bt6K+6o8P3lfEOWucrfYC3T4b3Lk/7Wq+9dMue4WmZ0KdbVwzu8Le5jnxZejC3p92gopCSgR4GpDiUZZsURYFDkeR/MKgBgvDevE7yxHWHOEKyyr9QzLHfsctmxjwaxZ4Lw5PYEWMNYP/aDx7sSC0ctC3+8PwmG3wHzDUQpkCbKZ/8nEIIafxTvX0X9L/vvm3gSSMg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=PYCcDFr9oBZ1ay1btoaoim+BeSDQ/pxZBKtFob/bDko=; b=oUUaDw2JgygriaMjvYmYenkF5megW5wskA4OguFSHJNmCIcmcdZsygq2qQnm2ZM1E2TXh6vL9UnHfmdK4O00hPJUbQNN1QIUaP0SDjB+vBc6d9N/Iax5cxgkfD6BUlvCUjvjMuKCC6ZQEsRf9HxYXOpiXDOEnzUY+lXizQZ7SVp3l5ecTwuzuy1BQcLx+uDDsIIC6qWjEyj/+4D47j/NZ6MNQ8dfrJE/5T9W3W5PXsAqBhr/VZMXL3fu7fMKfGQ4WiYcDX6gs2XRBtK58NtXNg45tedh0gPq2kwPna01BdNkyHxQOBD6VB6kIVH8hS/Mbe05l/74LHcLIKwhfy6suQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=os.amperecomputing.com; dmarc=pass action=none header.from=os.amperecomputing.com; dkim=pass header.d=os.amperecomputing.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=os.amperecomputing.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=PYCcDFr9oBZ1ay1btoaoim+BeSDQ/pxZBKtFob/bDko=; b=WjllIipTdJKk1znntIHgccxOSo/SSdX6A/dE5GCSDX8VrPVlQGJxhlnK8jBQJgYT74LqIWMKOkPpJ4y0v3HhLMN3Y7cc+KlWxSmjy+PlRTGzS6eG5FVk5azf3XBl66h2nxCE6xZ916IbSb8DMs3G/mrY5yqNi2bV1hqPZWN2izQ= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=os.amperecomputing.com; Received: from SJ0PR01MB6509.prod.exchangelabs.com (2603:10b6:a03:294::17) by CO1PR01MB7225.prod.exchangelabs.com (2603:10b6:303:160::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7316.33; Thu, 29 Feb 2024 16:25:33 +0000 Received: from SJ0PR01MB6509.prod.exchangelabs.com ([fe80::3bf9:56fb:dd12:56]) by SJ0PR01MB6509.prod.exchangelabs.com ([fe80::3bf9:56fb:dd12:56%6]) with mapi id 15.20.7316.037; Thu, 29 Feb 2024 16:25:33 +0000 From: Vanshidhar Konda To: Huisong Li , Beata Michalska Cc: Vanshidhar Konda , Ionela Voinescu , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rafael@kernel.org, sumitg@nvidia.com, zengheng4@huawei.com, yang@os.amperecomputing.com, will@kernel.org, sudeep.holla@arm.com, liuyonglong@huawei.com, zhanjie9@hisilicon.com, linux-acpi@vger.kernel.org Subject: [PATCH v1 3/3] ACPI: CPPC: Read CPC FFH counters in a single IPI Date: Thu, 29 Feb 2024 08:25:15 -0800 Message-ID: <20240229162520.970986-4-vanshikonda@os.amperecomputing.com> X-Mailer: git-send-email 2.43.1 In-Reply-To: <20240229162520.970986-1-vanshikonda@os.amperecomputing.com> References: <20240229162520.970986-1-vanshikonda@os.amperecomputing.com> X-ClientProxiedBy: CH0PR08CA0005.namprd08.prod.outlook.com (2603:10b6:610:33::10) To SJ0PR01MB6509.prod.exchangelabs.com (2603:10b6:a03:294::17) Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ0PR01MB6509:EE_|CO1PR01MB7225:EE_ X-MS-Office365-Filtering-Correlation-Id: b2853955-8707-48eb-1abc-08dc39430d67 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SJ0PR01MB6509.prod.exchangelabs.com;PTR:;CAT:NONE;SFS:(13230031);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: b2853955-8707-48eb-1abc-08dc39430d67 X-MS-Exchange-CrossTenant-AuthSource: SJ0PR01MB6509.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Feb 2024 16:25:33.1284 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: TEH+csnGl4oqncGnu/oRx528M6BFTBZO9FcdnV675svZBmlIZI6PdxawZQSAT3BPr9RRI1zu+cbuMUtMLMcYQpz0ObJlC2XTFmtnNi0Fcb8ZgSE3g9UpaeklDnkXaKq6 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO1PR01MB7225 The CPPC driver reads delivered and reference counters using cpc_read one at a time. This leads to inaccurate measurement of CPU frequency discussed in [1]. If the firmware indicates that both the registers are in the FFH interface the kernel can read the registers together in a single IPI. This has two benefits: 1. Reduces the number of IPIs needed to read the two registers 2. The two registers will be read in close proximity resulting in more accurate CPU frequency measurement [1]: https://lore.kernel.org/all/20230328193846.8757-1-yang@os.amperecomputing.com/ Signed-off-by: Vanshidhar Konda --- arch/arm64/kernel/topology.c | 37 ++++++++++++++++++++++++++++++++++++ drivers/acpi/cppc_acpi.c | 32 +++++++++++++++++++++++++++---- include/acpi/cppc_acpi.h | 13 +++++++++++++ 3 files changed, 78 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 8905eb0c681f..8207565f43ee 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -421,6 +421,43 @@ int cpc_read_ffh(int cpu, struct cpc_reg *reg, u64 *val) return ret; } +static void cpc_update_freq_counters(void *info) +{ + update_freq_counters_refs(); +} + +int cpc_read_regs_ffh(int cpu, struct ffh_cpc_reg_values *ffh_regs) +{ + struct amu_counters *ctrs = per_cpu_ptr(&cpu_samples, cpu); + int idx; + + if (!cpc_ffh_supported() || !freq_counters_valid(cpu)) + return -EOPNOTSUPP; + + if (WARN_ON_ONCE(irqs_disabled())) + return -EPERM; + + if (!idle_cpu(cpu)) + smp_call_function_single(cpu, cpc_update_freq_counters, NULL, 1); + + for (idx = 0; idx < MAX_NUM_CPC_REGS_FFH; idx++) { + + if (!ffh_regs->regs[idx].reg) + continue; + + switch ((u64)(ffh_regs->regs[idx].reg->address)) { + case 0x0: + ffh_regs->regs[idx].value = ctrs->core_cnt; + break; + case 0x1: + ffh_regs->regs[idx].value = ctrs->const_cnt; + break; + } + } + + return 0; +} + int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val) { return -EOPNOTSUPP; diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index d155a86a8614..55ffb1915e4f 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -113,6 +113,10 @@ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr); (cpc)->cpc_entry.reg.space_id == \ ACPI_ADR_SPACE_SYSTEM_IO) +#define CPC_IN_FFH(cpc) ((cpc)->type == ACPI_TYPE_BUFFER && \ + (cpc)->cpc_entry.reg.space_id == \ + ACPI_ADR_SPACE_FIXED_HARDWARE) + /* Evaluates to True if reg is a NULL register descriptor */ #define IS_NULL_REG(reg) ((reg)->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY && \ (reg)->address == 0 && \ @@ -974,6 +978,11 @@ int __weak cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val) return -ENOTSUPP; } +int __weak cpc_read_regs_ffh(int cpu, struct ffh_cpc_reg_values *regs) +{ + return -ENOTSUPP; +} + /* * Since cpc_read and cpc_write are called while holding pcc_lock, it should be * as fast as possible. We have already mapped the PCC subspace during init, so @@ -1317,7 +1326,7 @@ int cppc_get_perf_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs) int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum); struct cppc_pcc_data *pcc_ss_data = NULL; u64 delivered, reference, ref_perf, ctr_wrap_time; - int ret = 0, regs_in_pcc = 0; + int ret = 0, regs_in_pcc = 0, regs_read_in_ffh = 0; if (!cpc_desc) { pr_debug("No CPC descriptor for CPU:%d\n", cpunum); @@ -1353,8 +1362,23 @@ int cppc_get_perf_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs) } } - cpc_read(cpunum, delivered_reg, &delivered); - cpc_read(cpunum, reference_reg, &reference); + if (CPC_IN_FFH(delivered_reg) && CPC_IN_FFH(reference_reg)) { + struct ffh_cpc_reg_values ffh_regs; + + ffh_regs.regs[0].reg = &(delivered_reg->cpc_entry.reg); + ffh_regs.regs[1].reg = &(reference_reg->cpc_entry.reg); + ret = cpc_read_regs_ffh(cpunum, &ffh_regs); + if (!ret) { + delivered = ffh_regs.regs[0].value; + reference = ffh_regs.regs[1].value; + regs_read_in_ffh = 1; + } + } + + if (!regs_read_in_ffh) { + cpc_read(cpunum, delivered_reg, &delivered); + cpc_read(cpunum, reference_reg, &reference); + } cpc_read(cpunum, ref_perf_reg, &ref_perf); /* @@ -1366,7 +1390,7 @@ int cppc_get_perf_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs) if (CPC_SUPPORTED(ctr_wrap_reg)) cpc_read(cpunum, ctr_wrap_reg, &ctr_wrap_time); - if (!delivered || !reference || !ref_perf) { + if (!delivered || !reference || !ref_perf) { ret = -EFAULT; goto out_err; } diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index 3a0995f8bce8..0da614a50edd 100644 --- a/include/acpi/cppc_acpi.h +++ b/include/acpi/cppc_acpi.h @@ -137,6 +137,18 @@ struct cppc_cpudata { }; #ifdef CONFIG_ACPI_CPPC_LIB + +#define MAX_NUM_CPC_REGS_FFH 2 + +struct ffh_cpc_reg { + struct cpc_reg *reg; + u64 value; +}; + +struct ffh_cpc_reg_values { + struct ffh_cpc_reg regs[MAX_NUM_CPC_REGS_FFH]; +}; + extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf); extern int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf); extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs); @@ -153,6 +165,7 @@ extern unsigned int cppc_get_transition_latency(int cpu); extern bool cpc_ffh_supported(void); extern bool cpc_supported_by_cpu(void); extern int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val); +extern int cpc_read_regs_ffh(int cpu, struct ffh_cpc_reg_values *regs); extern int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val); extern int cppc_get_epp_perf(int cpunum, u64 *epp_perf); extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable);