Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933716AbcDTKAD (ORCPT ); Wed, 20 Apr 2016 06:00:03 -0400 Received: from mail-yw0-f196.google.com ([209.85.161.196]:33608 "EHLO mail-yw0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933283AbcDTJ75 (ORCPT ); Wed, 20 Apr 2016 05:59:57 -0400 MIME-Version: 1.0 In-Reply-To: <1461069013-13292-5-git-send-email-sudeep.holla@arm.com> References: <1461069013-13292-1-git-send-email-sudeep.holla@arm.com> <1461069013-13292-5-git-send-email-sudeep.holla@arm.com> Date: Wed, 20 Apr 2016 15:29:56 +0530 Message-ID: Subject: Re: [PATCH v4 4/5] arm64: add support for ACPI Low Power Idle(LPI) From: Vikas Sajjan To: Sudeep Holla Cc: "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, "linux-arm-kernel@lists.infradead.org" , Lorenzo Pieralisi , Al Stone , Prashanth Prakash , Ashwin Chaugule , Mark Rutland , Vikas C Sajjan , Sunil V L Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5853 Lines: 188 Hi Sudeep, On Tue, Apr 19, 2016 at 6:00 PM, Sudeep Holla wrote: > This patch adds appropriate callbacks to support ACPI Low Power Idle > (LPI) on ARM64. > > It also selects ARCH_SUPPORTS_ACPI_PROCESSOR_LPI if ACPI is enabled > on ARM64. > > Cc: Lorenzo Pieralisi > Cc: Mark Rutland > Cc: linux-arm-kernel@lists.infradead.org > Signed-off-by: Sudeep Holla > --- > arch/arm64/Kconfig | 1 + > arch/arm64/kernel/acpi.c | 34 ++++++++++++++++++++++++++++++++++ > drivers/firmware/psci.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 83 insertions(+) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 4f436220384f..e7536540387d 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -10,6 +10,7 @@ config ARM64 > select ARCH_HAS_SG_CHAIN > select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST > select ARCH_USE_CMPXCHG_LOCKREF > + select ARCH_SUPPORTS_ACPI_PROCESSOR_LPI if ACPI > select ARCH_SUPPORTS_ATOMIC_RMW > select ARCH_WANT_OPTIONAL_GPIOLIB > select ARCH_WANT_COMPAT_IPC_PARSE_VERSION > diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c > index d1ce8e2f98b9..3c05ad5957be 100644 > --- a/arch/arm64/kernel/acpi.c > +++ b/arch/arm64/kernel/acpi.c > @@ -18,6 +18,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -25,9 +26,11 @@ > #include > #include > > +#include > #include > #include > #include > +#include > > #ifdef CONFIG_ACPI_APEI > # include > @@ -211,6 +214,37 @@ void __init acpi_boot_table_init(void) > } > } > > +int acpi_processor_ffh_lpi_probe(unsigned int cpu) > +{ > + return arm_cpuidle_init(cpu); > +} > + This is generating warning as below: WARNING: vmlinux.o(.text+0x11024): Section mismatch in reference from the function acpi_processor_ffh_lpi_probe() to the function .init.text:arm_cpuidle_init() The function acpi_processor_ffh_lpi_probe() references the function __init arm_cpuidle_init(). This is often because acpi_processor_ffh_lpi_probe lacks a __init annotation or the annotation of arm_cpuidle_init is wrong. > +struct acpi_processor_lpi *lpi; > +int acpi_processor_ffh_lpi_enter(struct acpi_processor_lpi *lpi, int idx) Wondering how are you handling with Resource Dependencies for Idle. I mean _RDI needs to be taken care, since the dependency between the power resources and the LPI state is described in _RDI. > +{ > + int ret; > + > + if (!idx) { > + cpu_do_idle(); > + return idx; > + } > + > + /* TODO cpu_pm_{enter,exit} can be done in generic code ? */ > + ret = cpu_pm_enter(); > + if (!ret) { > + /* > + * Pass idle state index to cpu_suspend which in turn will > + * call the CPU ops suspend protocol with idle index as a > + * parameter. > + */ > + ret = arm_cpuidle_suspend(idx); > + > + cpu_pm_exit(); > + } > + > + return ret ? -1 : idx; > +} > + > #ifdef CONFIG_ACPI_APEI > pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) > { > diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c > index af6c5c839568..70cf2a500d4b 100644 > --- a/drivers/firmware/psci.c > +++ b/drivers/firmware/psci.c > @@ -24,6 +24,7 @@ > #include > #include > #include > +#include > > #include > > @@ -32,6 +33,7 @@ > #include > #include > #include > +#include > > /* > * While a 64-bit OS can make calls with SMC32 calling conventions, for some > @@ -316,8 +318,54 @@ static int psci_dt_cpu_init_idle(unsigned int cpu) > return ret; > } > > +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) > +{ > + int i, count; > + u32 *psci_states; > + struct acpi_processor *pr; > + struct acpi_processor_lpi *lpi; > + > + pr = per_cpu(processors, cpu); > + if (unlikely(!pr || !pr->flags.has_lpi)) > + return -EINVAL; > + > + /* > + * If the PSCI cpu_suspend function hook has not been initialized > + * idle states must not be enabled, so bail out > + */ > + if (!psci_ops.cpu_suspend) > + return -EOPNOTSUPP; > + > + count = pr->power.count - 1; > + if (!count) > + return -ENODEV; > + > + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); > + if (!psci_states) > + return -ENOMEM; > + > + for (i = 0; i < count; i++) { > + u32 state; > + > + lpi = &pr->power.lpi_states[i + 1]; > + state = lpi->address & 0xFFFFFFFF; > + if (!psci_power_state_is_valid(state)) { > + pr_warn("Invalid PSCI power state %#x\n", state); > + kfree(psci_states); > + return -EINVAL; > + } > + psci_states[i] = state; > + } > + /* Idle states parsed correctly, initialize per-cpu pointer */ > + per_cpu(psci_power_state, cpu) = psci_states; > + return 0; > +} > + > int psci_cpu_init_idle(unsigned int cpu) > { > + if (!acpi_disabled) > + return psci_acpi_cpu_init_idle(cpu); > + > return psci_dt_cpu_init_idle(cpu); > } > > -- > 1.9.1 >