From patchwork Wed Jun 11 16:18:38 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Pieralisi X-Patchwork-Id: 4337121 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 052D79F390 for ; Wed, 11 Jun 2014 16:18:47 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0897B202DD for ; Wed, 11 Jun 2014 16:18:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 049FC20303 for ; Wed, 11 Jun 2014 16:18:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932904AbaFKQSn (ORCPT ); Wed, 11 Jun 2014 12:18:43 -0400 Received: from service87.mimecast.com ([91.220.42.44]:55399 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932889AbaFKQSl (ORCPT ); Wed, 11 Jun 2014 12:18:41 -0400 Received: from cam-owa1.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Wed, 11 Jun 2014 17:18:39 +0100 Received: from red-moon.cambridge.arm.com ([10.1.255.212]) by cam-owa1.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Wed, 11 Jun 2014 17:18:33 +0100 From: Lorenzo Pieralisi To: linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, devicetree@vger.kernel.org Cc: Lorenzo Pieralisi , Mark Rutland , Sudeep Holla , Catalin Marinas , Charles Garcia Tobin , Nicolas Pitre , Rob Herring , Grant Likely , Peter De Schrijver , Santosh Shilimkar , Daniel Lezcano , Amit Kucheria , Vincent Guittot , Antti Miettinen , Stephen Boyd , Kevin Hilman , Sebastian Capella , Tomasz Figa , Mark Brown , Paul Walmsley , Chander Kashyap Subject: [PATCH v4 4/6] arm64: add PSCI CPU_SUSPEND based cpu_suspend support Date: Wed, 11 Jun 2014 17:18:38 +0100 Message-Id: <1402503520-8611-5-git-send-email-lorenzo.pieralisi@arm.com> X-Mailer: git-send-email 1.8.4 In-Reply-To: <1402503520-8611-1-git-send-email-lorenzo.pieralisi@arm.com> References: <1402503520-8611-1-git-send-email-lorenzo.pieralisi@arm.com> X-OriginalArrivalTime: 11 Jun 2014 16:18:33.0053 (UTC) FILETIME=[CA2968D0:01CF8590] X-MC-Unique: 114061117183901101 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch implements the cpu_suspend cpu operations method through the PSCI CPU_SUSPEND API. The PSCI implementation translates the idle state index passed by the cpu_suspend core call into a valid PSCI state according to the PSCI states initialized at boot by the PSCI suspend backend. Entry point is set to cpu_resume physical address, that represents the default kernel execution address following a CPU reset. Idle state indices missing a DT node description are initialized to power state standby WFI so that if called by the idle driver they provide the default behaviour. Reviewed-by: Sebastian Capella Signed-off-by: Lorenzo Pieralisi --- arch/arm64/include/asm/psci.h | 4 ++ arch/arm64/kernel/psci.c | 103 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 107 insertions(+) diff --git a/arch/arm64/include/asm/psci.h b/arch/arm64/include/asm/psci.h index e5312ea..16c1351 100644 --- a/arch/arm64/include/asm/psci.h +++ b/arch/arm64/include/asm/psci.h @@ -14,6 +14,10 @@ #ifndef __ASM_PSCI_H #define __ASM_PSCI_H +struct cpuidle_driver; int psci_init(void); +int __init psci_dt_register_idle_states(struct cpuidle_driver *, + struct device_node *[]); + #endif /* __ASM_PSCI_H */ diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 9e9798f..f708bcc 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -15,12 +15,14 @@ #define pr_fmt(fmt) "psci: " fmt +#include #include #include #include #include #include #include +#include #include #include @@ -28,6 +30,7 @@ #include #include #include +#include #include #define PSCI_POWER_STATE_TYPE_STANDBY 0 @@ -65,6 +68,8 @@ enum psci_function { PSCI_FN_MAX, }; +static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); + static u32 psci_function_id[PSCI_FN_MAX]; static int psci_to_linux_errno(int errno) @@ -93,6 +98,18 @@ static u32 psci_power_state_pack(struct psci_power_state state) & PSCI_0_2_POWER_STATE_AFFL_MASK); } +static void psci_power_state_unpack(u32 power_state, + struct psci_power_state *state) +{ + state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >> + PSCI_0_2_POWER_STATE_ID_SHIFT; + state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >> + PSCI_0_2_POWER_STATE_TYPE_SHIFT; + state->affinity_level = + (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >> + PSCI_0_2_POWER_STATE_AFFL_SHIFT; +} + /* * The following two functions are invoked via the invoke_psci_fn pointer * and will not be inlined, allowing us to piggyback on the AAPCS. @@ -199,6 +216,77 @@ static int psci_migrate_info_type(void) return err; } +int __init psci_dt_register_idle_states(struct cpuidle_driver *drv, + struct device_node *state_nodes[]) +{ + int cpu, i; + struct psci_power_state *psci_states; + const struct cpu_operations *cpu_ops_ptr; + + if (!state_nodes) + return -EINVAL; + /* + * This is belt-and-braces: make sure that if the idle + * specified protocol is psci, the cpu_ops have been + * initialized to psci operations. Anything else is + * a recipe for mayhem. + */ + for_each_cpu(cpu, drv->cpumask) { + cpu_ops_ptr = cpu_ops[cpu]; + if (WARN_ON(!cpu_ops_ptr || strcmp(cpu_ops_ptr->name, "psci"))) + return -EOPNOTSUPP; + } + + psci_states = kcalloc(drv->state_count, sizeof(*psci_states), + GFP_KERNEL); + + if (!psci_states) { + pr_warn("psci idle state allocation failed\n"); + return -ENOMEM; + } + + for_each_cpu(cpu, drv->cpumask) { + if (per_cpu(psci_power_state, cpu)) { + pr_warn("idle states already initialized on cpu %u\n", + cpu); + continue; + } + per_cpu(psci_power_state, cpu) = psci_states; + } + + + for (i = 0; i < drv->state_count; i++) { + u32 psci_power_state; + + if (!state_nodes[i]) { + /* + * An index with a missing node pointer falls back to + * simple STANDBYWFI + */ + psci_states[i].type = PSCI_POWER_STATE_TYPE_STANDBY; + continue; + } + + if (of_property_read_u32(state_nodes[i], "entry-method-param", + &psci_power_state)) { + pr_warn(" * %s missing entry-method-param property\n", + state_nodes[i]->full_name); + /* + * If entry-method-param property is missing, fall + * back to STANDBYWFI state + */ + psci_states[i].type = PSCI_POWER_STATE_TYPE_STANDBY; + continue; + } + + pr_debug("psci-power-state %#x index %u\n", psci_power_state, + i); + psci_power_state_unpack(psci_power_state, &psci_states[i]); + } + + return 0; +} + static int get_set_conduit_method(struct device_node *np) { const char *method; @@ -435,6 +523,18 @@ static int cpu_psci_cpu_kill(unsigned int cpu) } #endif +#ifdef CONFIG_ARM64_CPU_SUSPEND +static int cpu_psci_cpu_suspend(unsigned long index) +{ + struct psci_power_state *state = __get_cpu_var(psci_power_state); + + if (!state) + return -EOPNOTSUPP; + + return psci_ops.cpu_suspend(state[index], virt_to_phys(cpu_resume)); +} +#endif + const struct cpu_operations cpu_psci_ops = { .name = "psci", .cpu_init = cpu_psci_cpu_init, @@ -445,6 +545,9 @@ const struct cpu_operations cpu_psci_ops = { .cpu_die = cpu_psci_cpu_die, .cpu_kill = cpu_psci_cpu_kill, #endif +#ifdef CONFIG_ARM64_CPU_SUSPEND + .cpu_suspend = cpu_psci_cpu_suspend, +#endif }; #endif