From db50a74d8193944dd1ee488fd2a813a364fbbaa7 Mon Sep 17 00:00:00 2001 From: Prashanth Prakash Date: Wed, 15 Nov 2017 10:11:49 -0700 Subject: cpuidle: Add new macro to enter a retention idle state If a CPU is entering a low power idle state where it doesn't lose any context, then there is no need to call cpu_pm_enter()/cpu_pm_exit(). Add a new macro(CPU_PM_CPU_IDLE_ENTER_RETENTION) to be used by cpuidle drivers when they are entering retention state. By not calling cpu_pm_enter and cpu_pm_exit we reduce the latency involved in entering and exiting the retention idle states. CPU_PM_CPU_IDLE_ENTER_RETENTION assumes that no state is lost and hence CPU PM notifiers will not be called. We may need a broader change if we need to support partial retention states effeciently. On ARM64 based Qualcomm Server Platform we measured below overhead for for calling cpu_pm_enter and cpu_pm_exit for retention states. workload: stress --hdd #CPUs --hdd-bytes 32M -t 30 Average overhead of cpu_pm_enter - 1.2us Average overhead of cpu_pm_exit - 3.1us Acked-by: Rafael J. Wysocki Acked-by: Sudeep Holla Signed-off-by: Prashanth Prakash Signed-off-by: Catalin Marinas --- include/linux/cpuidle.h | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-) (limited to 'include') diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 8f7788d23b57..871f9e21810c 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -257,22 +257,30 @@ static inline int cpuidle_register_governor(struct cpuidle_governor *gov) {return 0;} #endif -#define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) \ -({ \ - int __ret; \ - \ - if (!idx) { \ - cpu_do_idle(); \ - return idx; \ - } \ - \ - __ret = cpu_pm_enter(); \ - if (!__ret) { \ - __ret = low_level_idle_enter(idx); \ - cpu_pm_exit(); \ - } \ - \ - __ret ? -1 : idx; \ +#define __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, is_retention) \ +({ \ + int __ret = 0; \ + \ + if (!idx) { \ + cpu_do_idle(); \ + return idx; \ + } \ + \ + if (!is_retention) \ + __ret = cpu_pm_enter(); \ + if (!__ret) { \ + __ret = low_level_idle_enter(idx); \ + if (!is_retention) \ + cpu_pm_exit(); \ + } \ + \ + __ret ? -1 : idx; \ }) +#define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) \ + __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, 0) + +#define CPU_PM_CPU_IDLE_ENTER_RETENTION(low_level_idle_enter, idx) \ + __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, 1) + #endif /* _LINUX_CPUIDLE_H */ -- cgit v1.2.3 From a0e71cd9b1a0195f96500b2268759873ff8ff819 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Tue, 2 Jan 2018 11:25:27 +0000 Subject: of: Add helper for mapping device node to logical CPU number Add a helper to map a device node to a logical CPU number to avoid duplication. Currently this is open coded in different places (e.g gic-v3, coresight). The helper tries to map device node to a "possible" logical CPU id, which may not be online yet. It is the responsibility of the user to make sure that the CPU is online. The helper uses of_cpu_device_node_get() to retrieve the device node for a given CPU (which uses per_cpu data if available else falls back to slower of_get_cpu_node()). Cc: devicetree@vger.kernel.org Cc: Frank Rowand Cc: Mark Rutland Cc: Sudeep Holla Reviewed-by: Marc Zyngier Reviewed-by: Rob Herring Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon --- drivers/of/base.c | 26 ++++++++++++++++++++++++++ include/linux/of.h | 7 +++++++ 2 files changed, 33 insertions(+) (limited to 'include') diff --git a/drivers/of/base.c b/drivers/of/base.c index 26618ba8f92a..a9d6fe86585b 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -315,6 +315,32 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) } EXPORT_SYMBOL(of_get_cpu_node); +/** + * of_cpu_node_to_id: Get the logical CPU number for a given device_node + * + * @cpu_node: Pointer to the device_node for CPU. + * + * Returns the logical CPU number of the given CPU device_node. + * Returns -ENODEV if the CPU is not found. + */ +int of_cpu_node_to_id(struct device_node *cpu_node) +{ + int cpu; + bool found = false; + struct device_node *np; + + for_each_possible_cpu(cpu) { + np = of_cpu_device_node_get(cpu); + found = (cpu_node == np); + of_node_put(np); + if (found) + return cpu; + } + + return -ENODEV; +} +EXPORT_SYMBOL(of_cpu_node_to_id); + /** * __of_device_is_compatible() - Check if the node matches given constraints * @device: pointer to node diff --git a/include/linux/of.h b/include/linux/of.h index d3dea1d1e3a9..173102dafb07 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -544,6 +544,8 @@ const char *of_prop_next_string(struct property *prop, const char *cur); bool of_console_check(struct device_node *dn, char *name, int index); +extern int of_cpu_node_to_id(struct device_node *np); + #else /* CONFIG_OF */ static inline void of_core_init(void) @@ -916,6 +918,11 @@ static inline void of_property_clear_flag(struct property *p, unsigned long flag { } +static inline int of_cpu_node_to_id(struct device_node *np) +{ + return -ENODEV; +} + #define of_match_ptr(_ptr) NULL #define of_match_node(_matches, _node) NULL #endif /* CONFIG_OF */ -- cgit v1.2.3 From d68e3ba5303f7e1099f51fdcd155f5263da8569b Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 2 Jan 2018 21:45:41 +0000 Subject: drivers/firmware: Expose psci_get_version through psci_ops structure Entry into recent versions of ARM Trusted Firmware will invalidate the CPU branch predictor state in order to protect against aliasing attacks. This patch exposes the PSCI "VERSION" function via psci_ops, so that it can be invoked outside of the PSCI driver where necessary. Acked-by: Lorenzo Pieralisi Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- drivers/firmware/psci.c | 2 ++ include/linux/psci.h | 1 + 2 files changed, 3 insertions(+) (limited to 'include') diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index d687ca3d5049..8b25d31e8401 100644 --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -496,6 +496,8 @@ static void __init psci_init_migrate(void) static void __init psci_0_2_set_functions(void) { pr_info("Using standard PSCI v0.2 function IDs\n"); + psci_ops.get_version = psci_get_version; + psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_FN_NATIVE(0_2, CPU_SUSPEND); psci_ops.cpu_suspend = psci_cpu_suspend; diff --git a/include/linux/psci.h b/include/linux/psci.h index bdea1cb5e1db..6306ab10af18 100644 --- a/include/linux/psci.h +++ b/include/linux/psci.h @@ -26,6 +26,7 @@ int psci_cpu_init_idle(unsigned int cpu); int psci_cpu_suspend_enter(unsigned long index); struct psci_operations { + u32 (*get_version)(void); int (*cpu_suspend)(u32 state, unsigned long entry_point); int (*cpu_off)(u32 state); int (*cpu_on)(unsigned long cpuid, unsigned long entry_point); -- cgit v1.2.3 From ad6eb31ef90355993eb55ff77e0e855ae7d91e4c Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 8 Jan 2018 15:38:09 +0000 Subject: firmware: arm_sdei: Add driver for Software Delegated Exceptions The Software Delegated Exception Interface (SDEI) is an ARM standard for registering callbacks from the platform firmware into the OS. This is typically used to implement firmware notifications (such as firmware-first RAS) or promote an IRQ that has been promoted to a firmware-assisted NMI. Add the code for detecting the SDEI version and the framework for registering and unregistering events. Subsequent patches will add the arch-specific backend code and the necessary power management hooks. Only shared events are supported, power management, private events and discovery for ACPI systems will be added by later patches. Signed-off-by: James Morse Signed-off-by: Catalin Marinas --- MAINTAINERS | 9 + arch/arm64/include/asm/sdei.h | 8 + drivers/firmware/Kconfig | 8 + drivers/firmware/Makefile | 1 + drivers/firmware/arm_sdei.c | 619 ++++++++++++++++++++++++++++++++++++++++++ include/linux/arm_sdei.h | 79 ++++++ include/uapi/linux/arm_sdei.h | 73 +++++ 7 files changed, 797 insertions(+) create mode 100644 arch/arm64/include/asm/sdei.h create mode 100644 drivers/firmware/arm_sdei.c create mode 100644 include/linux/arm_sdei.h create mode 100644 include/uapi/linux/arm_sdei.h (limited to 'include') diff --git a/MAINTAINERS b/MAINTAINERS index 82ad0eabce4f..c06885c4c0f1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12618,6 +12618,15 @@ L: linux-media@vger.kernel.org S: Supported F: drivers/media/pci/solo6x10/ +SOFTWARE DELEGATED EXCEPTION INTERFACE (SDEI) +M: James Morse +L: linux-arm-kernel@lists.infradead.org +S: Maintained +F: Documentation/devicetree/bindings/arm/firmware/sdei.txt +F: drivers/firmware/arm_sdei.c +F: include/linux/sdei.h +F: include/uapi/linux/sdei.h + SOFTWARE RAID (Multiple Disks) SUPPORT M: Shaohua Li L: linux-raid@vger.kernel.org diff --git a/arch/arm64/include/asm/sdei.h b/arch/arm64/include/asm/sdei.h new file mode 100644 index 000000000000..59f26b6e673d --- /dev/null +++ b/arch/arm64/include/asm/sdei.h @@ -0,0 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2017 Arm Ltd. +#ifndef __ASM_SDEI_H +#define __ASM_SDEI_H + +/* Later patches add the arch specific bits */ + +#endif /* __ASM_SDEI_H */ diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index fa87a055905e..e77f77caa0f3 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -48,6 +48,14 @@ config ARM_SCPI_POWER_DOMAIN This enables support for the SCPI power domains which can be enabled or disabled via the SCP firmware +config ARM_SDE_INTERFACE + bool "ARM Software Delegated Exception Interface (SDEI)" + depends on ARM64 + help + The Software Delegated Exception Interface (SDEI) is an ARM + standard for registering callbacks from the platform firmware + into the OS. This is typically used to implement RAS notifications. + config EDD tristate "BIOS Enhanced Disk Drive calls determine boot disk" depends on X86 diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index feaa890197f3..b248238ddc6a 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_ARM_PSCI_FW) += psci.o obj-$(CONFIG_ARM_PSCI_CHECKER) += psci_checker.o obj-$(CONFIG_ARM_SCPI_PROTOCOL) += arm_scpi.o obj-$(CONFIG_ARM_SCPI_POWER_DOMAIN) += scpi_pm_domain.o +obj-$(CONFIG_ARM_SDE_INTERFACE) += arm_sdei.o obj-$(CONFIG_DMI) += dmi_scan.o obj-$(CONFIG_DMI_SYSFS) += dmi-sysfs.o obj-$(CONFIG_EDD) += edd.o diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c new file mode 100644 index 000000000000..8da173cc7e43 --- /dev/null +++ b/drivers/firmware/arm_sdei.c @@ -0,0 +1,619 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2017 Arm Ltd. +#define pr_fmt(fmt) "sdei: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * The call to use to reach the firmware. + */ +static asmlinkage void (*sdei_firmware_call)(unsigned long function_id, + unsigned long arg0, unsigned long arg1, + unsigned long arg2, unsigned long arg3, + unsigned long arg4, struct arm_smccc_res *res); + +/* entry point from firmware to arch asm code */ +static unsigned long sdei_entry_point; + +struct sdei_event { + struct list_head list; + u32 event_num; + u8 type; + u8 priority; + + /* This pointer is handed to firmware as the event argument. */ + struct sdei_registered_event *registered; +}; + +/* Take the mutex for any API call or modification. Take the mutex first. */ +static DEFINE_MUTEX(sdei_events_lock); + +/* and then hold this when modifying the list */ +static DEFINE_SPINLOCK(sdei_list_lock); +static LIST_HEAD(sdei_list); + +static int sdei_to_linux_errno(unsigned long sdei_err) +{ + switch (sdei_err) { + case SDEI_NOT_SUPPORTED: + return -EOPNOTSUPP; + case SDEI_INVALID_PARAMETERS: + return -EINVAL; + case SDEI_DENIED: + return -EPERM; + case SDEI_PENDING: + return -EINPROGRESS; + case SDEI_OUT_OF_RESOURCE: + return -ENOMEM; + } + + /* Not an error value ... */ + return sdei_err; +} + +/* + * If x0 is any of these values, then the call failed, use sdei_to_linux_errno() + * to translate. + */ +static int sdei_is_err(struct arm_smccc_res *res) +{ + switch (res->a0) { + case SDEI_NOT_SUPPORTED: + case SDEI_INVALID_PARAMETERS: + case SDEI_DENIED: + case SDEI_PENDING: + case SDEI_OUT_OF_RESOURCE: + return true; + } + + return false; +} + +static int invoke_sdei_fn(unsigned long function_id, unsigned long arg0, + unsigned long arg1, unsigned long arg2, + unsigned long arg3, unsigned long arg4, + u64 *result) +{ + int err = 0; + struct arm_smccc_res res; + + if (sdei_firmware_call) { + sdei_firmware_call(function_id, arg0, arg1, arg2, arg3, arg4, + &res); + if (sdei_is_err(&res)) + err = sdei_to_linux_errno(res.a0); + } else { + /* + * !sdei_firmware_call means we failed to probe or called + * sdei_mark_interface_broken(). -EIO is not an error returned + * by sdei_to_linux_errno() and is used to suppress messages + * from this driver. + */ + err = -EIO; + res.a0 = SDEI_NOT_SUPPORTED; + } + + if (result) + *result = res.a0; + + return err; +} + +static struct sdei_event *sdei_event_find(u32 event_num) +{ + struct sdei_event *e, *found = NULL; + + lockdep_assert_held(&sdei_events_lock); + + spin_lock(&sdei_list_lock); + list_for_each_entry(e, &sdei_list, list) { + if (e->event_num == event_num) { + found = e; + break; + } + } + spin_unlock(&sdei_list_lock); + + return found; +} + +int sdei_api_event_context(u32 query, u64 *result) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_CONTEXT, query, 0, 0, 0, 0, + result); +} +NOKPROBE_SYMBOL(sdei_api_event_context); + +static int sdei_api_event_get_info(u32 event, u32 info, u64 *result) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_GET_INFO, event, info, 0, + 0, 0, result); +} + +static struct sdei_event *sdei_event_create(u32 event_num, + sdei_event_callback *cb, + void *cb_arg) +{ + int err; + u64 result; + struct sdei_event *event; + struct sdei_registered_event *reg; + + lockdep_assert_held(&sdei_events_lock); + + event = kzalloc(sizeof(*event), GFP_KERNEL); + if (!event) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&event->list); + event->event_num = event_num; + + err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY, + &result); + if (err) { + kfree(event); + return ERR_PTR(err); + } + event->priority = result; + + err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_TYPE, + &result); + if (err) { + kfree(event); + return ERR_PTR(err); + } + event->type = result; + + if (event->type == SDEI_EVENT_TYPE_SHARED) { + reg = kzalloc(sizeof(*reg), GFP_KERNEL); + if (!reg) { + kfree(event); + return ERR_PTR(-ENOMEM); + } + + reg->event_num = event_num; + reg->priority = event->priority; + + reg->callback = cb; + reg->callback_arg = cb_arg; + event->registered = reg; + } + + if (sdei_event_find(event_num)) { + kfree(event->registered); + kfree(event); + event = ERR_PTR(-EBUSY); + } else { + spin_lock(&sdei_list_lock); + list_add(&event->list, &sdei_list); + spin_unlock(&sdei_list_lock); + } + + return event; +} + +static void sdei_event_destroy(struct sdei_event *event) +{ + lockdep_assert_held(&sdei_events_lock); + + spin_lock(&sdei_list_lock); + list_del(&event->list); + spin_unlock(&sdei_list_lock); + + if (event->type == SDEI_EVENT_TYPE_SHARED) + kfree(event->registered); + + kfree(event); +} + +static int sdei_api_get_version(u64 *version) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_VERSION, 0, 0, 0, 0, 0, version); +} + +int sdei_mask_local_cpu(void) +{ + int err; + + WARN_ON_ONCE(preemptible()); + + err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL); + if (err && err != -EIO) { + pr_warn_once("failed to mask CPU[%u]: %d\n", + smp_processor_id(), err); + return err; + } + + return 0; +} + +static void _ipi_mask_cpu(void *ignored) +{ + sdei_mask_local_cpu(); +} + +int sdei_unmask_local_cpu(void) +{ + int err; + + WARN_ON_ONCE(preemptible()); + + err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL); + if (err && err != -EIO) { + pr_warn_once("failed to unmask CPU[%u]: %d\n", + smp_processor_id(), err); + return err; + } + + return 0; +} + +static void _ipi_unmask_cpu(void *ignored) +{ + sdei_unmask_local_cpu(); +} + +static void _ipi_private_reset(void *ignored) +{ + int err; + + err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0, + NULL); + if (err && err != -EIO) + pr_warn_once("failed to reset CPU[%u]: %d\n", + smp_processor_id(), err); +} + +static int sdei_api_shared_reset(void) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_SHARED_RESET, 0, 0, 0, 0, 0, + NULL); +} + +static void sdei_mark_interface_broken(void) +{ + pr_err("disabling SDEI firmware interface\n"); + on_each_cpu(&_ipi_mask_cpu, NULL, true); + sdei_firmware_call = NULL; +} + +static int sdei_platform_reset(void) +{ + int err; + + on_each_cpu(&_ipi_private_reset, NULL, true); + err = sdei_api_shared_reset(); + if (err) { + pr_err("Failed to reset platform: %d\n", err); + sdei_mark_interface_broken(); + } + + return err; +} + +static int sdei_api_event_enable(u32 event_num) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_ENABLE, event_num, 0, 0, 0, + 0, NULL); +} + +int sdei_event_enable(u32 event_num) +{ + int err = -EINVAL; + struct sdei_event *event; + + mutex_lock(&sdei_events_lock); + event = sdei_event_find(event_num); + if (!event) { + mutex_unlock(&sdei_events_lock); + return -ENOENT; + } + + if (event->type == SDEI_EVENT_TYPE_SHARED) + err = sdei_api_event_enable(event->event_num); + mutex_unlock(&sdei_events_lock); + + return err; +} +EXPORT_SYMBOL(sdei_event_enable); + +static int sdei_api_event_disable(u32 event_num) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_DISABLE, event_num, 0, 0, + 0, 0, NULL); +} + +int sdei_event_disable(u32 event_num) +{ + int err = -EINVAL; + struct sdei_event *event; + + mutex_lock(&sdei_events_lock); + event = sdei_event_find(event_num); + if (!event) { + mutex_unlock(&sdei_events_lock); + return -ENOENT; + } + + if (event->type == SDEI_EVENT_TYPE_SHARED) + err = sdei_api_event_disable(event->event_num); + mutex_unlock(&sdei_events_lock); + + return err; +} +EXPORT_SYMBOL(sdei_event_disable); + +static int sdei_api_event_unregister(u32 event_num) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_UNREGISTER, event_num, 0, + 0, 0, 0, NULL); +} + +static int _sdei_event_unregister(struct sdei_event *event) +{ + lockdep_assert_held(&sdei_events_lock); + + if (event->type == SDEI_EVENT_TYPE_SHARED) + return sdei_api_event_unregister(event->event_num); + + return -EINVAL; +} + +int sdei_event_unregister(u32 event_num) +{ + int err; + struct sdei_event *event; + + WARN_ON(in_nmi()); + + mutex_lock(&sdei_events_lock); + event = sdei_event_find(event_num); + do { + if (!event) { + pr_warn("Event %u not registered\n", event_num); + err = -ENOENT; + break; + } + + err = _sdei_event_unregister(event); + if (err) + break; + + sdei_event_destroy(event); + } while (0); + mutex_unlock(&sdei_events_lock); + + return err; +} +EXPORT_SYMBOL(sdei_event_unregister); + +static int sdei_api_event_register(u32 event_num, unsigned long entry_point, + void *arg, u64 flags, u64 affinity) +{ + return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_REGISTER, event_num, + (unsigned long)entry_point, (unsigned long)arg, + flags, affinity, NULL); +} + +static int _sdei_event_register(struct sdei_event *event) +{ + lockdep_assert_held(&sdei_events_lock); + + if (event->type == SDEI_EVENT_TYPE_SHARED) + return sdei_api_event_register(event->event_num, + sdei_entry_point, + event->registered, + SDEI_EVENT_REGISTER_RM_ANY, 0); + + return -EINVAL; +} + +int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg) +{ + int err; + struct sdei_event *event; + + WARN_ON(in_nmi()); + + mutex_lock(&sdei_events_lock); + do { + if (sdei_event_find(event_num)) { + pr_warn("Event %u already registered\n", event_num); + err = -EBUSY; + break; + } + + event = sdei_event_create(event_num, cb, arg); + if (IS_ERR(event)) { + err = PTR_ERR(event); + pr_warn("Failed to create event %u: %d\n", event_num, + err); + break; + } + + err = _sdei_event_register(event); + if (err) { + sdei_event_destroy(event); + pr_warn("Failed to register event %u: %d\n", event_num, + err); + } + } while (0); + mutex_unlock(&sdei_events_lock); + + return err; +} +EXPORT_SYMBOL(sdei_event_register); + +static void sdei_smccc_smc(unsigned long function_id, + unsigned long arg0, unsigned long arg1, + unsigned long arg2, unsigned long arg3, + unsigned long arg4, struct arm_smccc_res *res) +{ + arm_smccc_smc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res); +} + +static void sdei_smccc_hvc(unsigned long function_id, + unsigned long arg0, unsigned long arg1, + unsigned long arg2, unsigned long arg3, + unsigned long arg4, struct arm_smccc_res *res) +{ + arm_smccc_hvc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res); +} + +static int sdei_get_conduit(struct platform_device *pdev) +{ + const char *method; + struct device_node *np = pdev->dev.of_node; + + sdei_firmware_call = NULL; + if (np) { + if (of_property_read_string(np, "method", &method)) { + pr_warn("missing \"method\" property\n"); + return CONDUIT_INVALID; + } + + if (!strcmp("hvc", method)) { + sdei_firmware_call = &sdei_smccc_hvc; + return CONDUIT_HVC; + } else if (!strcmp("smc", method)) { + sdei_firmware_call = &sdei_smccc_smc; + return CONDUIT_SMC; + } + + pr_warn("invalid \"method\" property: %s\n", method); + } + + return CONDUIT_INVALID; +} + +static int sdei_probe(struct platform_device *pdev) +{ + int err; + u64 ver = 0; + int conduit; + + conduit = sdei_get_conduit(pdev); + if (!sdei_firmware_call) + return 0; + + err = sdei_api_get_version(&ver); + if (err == -EOPNOTSUPP) + pr_err("advertised but not implemented in platform firmware\n"); + if (err) { + pr_err("Failed to get SDEI version: %d\n", err); + sdei_mark_interface_broken(); + return err; + } + + pr_info("SDEIv%d.%d (0x%x) detected in firmware.\n", + (int)SDEI_VERSION_MAJOR(ver), (int)SDEI_VERSION_MINOR(ver), + (int)SDEI_VERSION_VENDOR(ver)); + + if (SDEI_VERSION_MAJOR(ver) != 1) { + pr_warn("Conflicting SDEI version detected.\n"); + sdei_mark_interface_broken(); + return -EINVAL; + } + + err = sdei_platform_reset(); + if (err) + return err; + + sdei_entry_point = sdei_arch_get_entry_point(conduit); + if (!sdei_entry_point) { + /* Not supported due to hardware or boot configuration */ + sdei_mark_interface_broken(); + return 0; + } + + on_each_cpu(&_ipi_unmask_cpu, NULL, false); + + return 0; +} + +static const struct of_device_id sdei_of_match[] = { + { .compatible = "arm,sdei-1.0" }, + {} +}; + +static struct platform_driver sdei_driver = { + .driver = { + .name = "sdei", + .of_match_table = sdei_of_match, + }, + .probe = sdei_probe, +}; + +static bool __init sdei_present_dt(void) +{ + struct platform_device *pdev; + struct device_node *np, *fw_np; + + fw_np = of_find_node_by_name(NULL, "firmware"); + if (!fw_np) + return false; + + np = of_find_matching_node(fw_np, sdei_of_match); + of_node_put(fw_np); + if (!np) + return false; + + pdev = of_platform_device_create(np, sdei_driver.driver.name, NULL); + of_node_put(np); + if (IS_ERR(pdev)) + return false; + + return true; +} + +static int __init sdei_init(void) +{ + if (sdei_present_dt()) + platform_driver_register(&sdei_driver); + + return 0; +} + +subsys_initcall_sync(sdei_init); + +int sdei_event_handler(struct pt_regs *regs, + struct sdei_registered_event *arg) +{ + int err; + mm_segment_t orig_addr_limit; + u32 event_num = arg->event_num; + + orig_addr_limit = get_fs(); + set_fs(USER_DS); + + err = arg->callback(event_num, regs, arg->callback_arg); + if (err) + pr_err_ratelimited("event %u on CPU %u failed with error: %d\n", + event_num, smp_processor_id(), err); + + set_fs(orig_addr_limit); + + return err; +} +NOKPROBE_SYMBOL(sdei_event_handler); diff --git a/include/linux/arm_sdei.h b/include/linux/arm_sdei.h new file mode 100644 index 000000000000..942afbd544b7 --- /dev/null +++ b/include/linux/arm_sdei.h @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2017 Arm Ltd. +#ifndef __LINUX_ARM_SDEI_H +#define __LINUX_ARM_SDEI_H + +#include + +enum sdei_conduit_types { + CONDUIT_INVALID = 0, + CONDUIT_SMC, + CONDUIT_HVC, +}; + +#include + +/* Arch code should override this to set the entry point from firmware... */ +#ifndef sdei_arch_get_entry_point +#define sdei_arch_get_entry_point(conduit) (0) +#endif + +/* + * When an event occurs sdei_event_handler() will call a user-provided callback + * like this in NMI context on the CPU that received the event. + */ +typedef int (sdei_event_callback)(u32 event, struct pt_regs *regs, void *arg); + +/* + * Register your callback to claim an event. The event must be described + * by firmware. + */ +int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg); + +/* + * Calls to sdei_event_unregister() may return EINPROGRESS. Keep calling + * it until it succeeds. + */ +int sdei_event_unregister(u32 event_num); + +int sdei_event_enable(u32 event_num); +int sdei_event_disable(u32 event_num); + +#ifdef CONFIG_ARM_SDE_INTERFACE +/* For use by arch code when CPU hotplug notifiers are not appropriate. */ +int sdei_mask_local_cpu(void); +int sdei_unmask_local_cpu(void); +#else +static inline int sdei_mask_local_cpu(void) { return 0; } +static inline int sdei_unmask_local_cpu(void) { return 0; } +#endif /* CONFIG_ARM_SDE_INTERFACE */ + + +/* + * This struct represents an event that has been registered. The driver + * maintains a list of all events, and which ones are registered. (Private + * events have one entry in the list, but are registered on each CPU). + * A pointer to this struct is passed to firmware, and back to the event + * handler. The event handler can then use this to invoke the registered + * callback, without having to walk the list. + * + * For CPU private events, this structure is per-cpu. + */ +struct sdei_registered_event { + /* For use by arch code: */ + struct pt_regs interrupted_regs; + + sdei_event_callback *callback; + void *callback_arg; + u32 event_num; + u8 priority; +}; + +/* The arch code entry point should then call this when an event arrives. */ +int notrace sdei_event_handler(struct pt_regs *regs, + struct sdei_registered_event *arg); + +/* arch code may use this to retrieve the extra registers. */ +int sdei_api_event_context(u32 query, u64 *result); + +#endif /* __LINUX_ARM_SDEI_H */ diff --git a/include/uapi/linux/arm_sdei.h b/include/uapi/linux/arm_sdei.h new file mode 100644 index 000000000000..af0630ba5437 --- /dev/null +++ b/include/uapi/linux/arm_sdei.h @@ -0,0 +1,73 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* Copyright (C) 2017 Arm Ltd. */ +#ifndef _UAPI_LINUX_ARM_SDEI_H +#define _UAPI_LINUX_ARM_SDEI_H + +#define SDEI_1_0_FN_BASE 0xC4000020 +#define SDEI_1_0_MASK 0xFFFFFFE0 +#define SDEI_1_0_FN(n) (SDEI_1_0_FN_BASE + (n)) + +#define SDEI_1_0_FN_SDEI_VERSION SDEI_1_0_FN(0x00) +#define SDEI_1_0_FN_SDEI_EVENT_REGISTER SDEI_1_0_FN(0x01) +#define SDEI_1_0_FN_SDEI_EVENT_ENABLE SDEI_1_0_FN(0x02) +#define SDEI_1_0_FN_SDEI_EVENT_DISABLE SDEI_1_0_FN(0x03) +#define SDEI_1_0_FN_SDEI_EVENT_CONTEXT SDEI_1_0_FN(0x04) +#define SDEI_1_0_FN_SDEI_EVENT_COMPLETE SDEI_1_0_FN(0x05) +#define SDEI_1_0_FN_SDEI_EVENT_COMPLETE_AND_RESUME SDEI_1_0_FN(0x06) +#define SDEI_1_0_FN_SDEI_EVENT_UNREGISTER SDEI_1_0_FN(0x07) +#define SDEI_1_0_FN_SDEI_EVENT_STATUS SDEI_1_0_FN(0x08) +#define SDEI_1_0_FN_SDEI_EVENT_GET_INFO SDEI_1_0_FN(0x09) +#define SDEI_1_0_FN_SDEI_EVENT_ROUTING_SET SDEI_1_0_FN(0x0A) +#define SDEI_1_0_FN_SDEI_PE_MASK SDEI_1_0_FN(0x0B) +#define SDEI_1_0_FN_SDEI_PE_UNMASK SDEI_1_0_FN(0x0C) +#define SDEI_1_0_FN_SDEI_INTERRUPT_BIND SDEI_1_0_FN(0x0D) +#define SDEI_1_0_FN_SDEI_INTERRUPT_RELEASE SDEI_1_0_FN(0x0E) +#define SDEI_1_0_FN_SDEI_PRIVATE_RESET SDEI_1_0_FN(0x11) +#define SDEI_1_0_FN_SDEI_SHARED_RESET SDEI_1_0_FN(0x12) + +#define SDEI_VERSION_MAJOR_SHIFT 48 +#define SDEI_VERSION_MAJOR_MASK 0x7fff +#define SDEI_VERSION_MINOR_SHIFT 32 +#define SDEI_VERSION_MINOR_MASK 0xffff +#define SDEI_VERSION_VENDOR_SHIFT 0 +#define SDEI_VERSION_VENDOR_MASK 0xffffffff + +#define SDEI_VERSION_MAJOR(x) (x>>SDEI_VERSION_MAJOR_SHIFT & SDEI_VERSION_MAJOR_MASK) +#define SDEI_VERSION_MINOR(x) (x>>SDEI_VERSION_MINOR_SHIFT & SDEI_VERSION_MINOR_MASK) +#define SDEI_VERSION_VENDOR(x) (x>>SDEI_VERSION_VENDOR_SHIFT & SDEI_VERSION_VENDOR_MASK) + +/* SDEI return values */ +#define SDEI_SUCCESS 0 +#define SDEI_NOT_SUPPORTED -1 +#define SDEI_INVALID_PARAMETERS -2 +#define SDEI_DENIED -3 +#define SDEI_PENDING -5 +#define SDEI_OUT_OF_RESOURCE -10 + +/* EVENT_REGISTER flags */ +#define SDEI_EVENT_REGISTER_RM_ANY 0 +#define SDEI_EVENT_REGISTER_RM_PE 1 + +/* EVENT_STATUS return value bits */ +#define SDEI_EVENT_STATUS_RUNNING 2 +#define SDEI_EVENT_STATUS_ENABLED 1 +#define SDEI_EVENT_STATUS_REGISTERED 0 + +/* EVENT_COMPLETE status values */ +#define SDEI_EV_HANDLED 0 +#define SDEI_EV_FAILED 1 + +/* GET_INFO values */ +#define SDEI_EVENT_INFO_EV_TYPE 0 +#define SDEI_EVENT_INFO_EV_SIGNALED 1 +#define SDEI_EVENT_INFO_EV_PRIORITY 2 +#define SDEI_EVENT_INFO_EV_ROUTING_MODE 3 +#define SDEI_EVENT_INFO_EV_ROUTING_AFF 4 + +/* and their results */ +#define SDEI_EVENT_TYPE_PRIVATE 0 +#define SDEI_EVENT_TYPE_SHARED 1 +#define SDEI_EVENT_PRIORITY_NORMAL 0 +#define SDEI_EVENT_PRIORITY_CRITICAL 1 + +#endif /* _UAPI_LINUX_ARM_SDEI_H */ -- cgit v1.2.3 From da351827240e1705cca64bb8ae526f0ce1068048 Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 8 Jan 2018 15:38:13 +0000 Subject: firmware: arm_sdei: Add support for CPU and system power states When a CPU enters an idle lower-power state or is powering off, we need to mask SDE events so that no events can be delivered while we are messing with the MMU as the registered entry points won't be valid. If the system reboots, we want to unregister all events and mask the CPUs. For kexec this allows us to hand a clean slate to the next kernel instead of relying on it to call sdei_{private,system}_data_reset(). For hibernate we unregister all events and re-register them on restore, in case we restored with the SDE code loaded at a different address. (e.g. KASLR). Add all the notifiers necessary to do this. We only support shared events so all events are left registered and enabled over CPU hotplug. Reviewed-by: Lorenzo Pieralisi Signed-off-by: James Morse [catalin.marinas@arm.com: added CPU_PM_ENTER_FAILED case] Signed-off-by: Catalin Marinas --- drivers/firmware/arm_sdei.c | 256 +++++++++++++++++++++++++++++++++++++++++++- include/linux/cpuhotplug.h | 1 + 2 files changed, 256 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c index 8da173cc7e43..c503bc5222ed 100644 --- a/drivers/firmware/arm_sdei.c +++ b/drivers/firmware/arm_sdei.c @@ -7,6 +7,8 @@ #include #include #include +#include +#include #include #include #include @@ -14,12 +16,15 @@ #include #include #include +#include #include #include #include #include +#include #include #include +#include #include #include #include @@ -37,7 +42,11 @@ static asmlinkage void (*sdei_firmware_call)(unsigned long function_id, static unsigned long sdei_entry_point; struct sdei_event { + /* These three are protected by the sdei_list_lock */ struct list_head list; + bool reregister; + bool reenable; + u32 event_num; u8 type; u8 priority; @@ -253,6 +262,11 @@ static void _ipi_mask_cpu(void *ignored) sdei_mask_local_cpu(); } +static int sdei_cpuhp_down(unsigned int ignored) +{ + return sdei_mask_local_cpu(); +} + int sdei_unmask_local_cpu(void) { int err; @@ -274,6 +288,11 @@ static void _ipi_unmask_cpu(void *ignored) sdei_unmask_local_cpu(); } +static int sdei_cpuhp_up(unsigned int ignored) +{ + return sdei_unmask_local_cpu(); +} + static void _ipi_private_reset(void *ignored) { int err; @@ -330,6 +349,10 @@ int sdei_event_enable(u32 event_num) return -ENOENT; } + spin_lock(&sdei_list_lock); + event->reenable = true; + spin_unlock(&sdei_list_lock); + if (event->type == SDEI_EVENT_TYPE_SHARED) err = sdei_api_event_enable(event->event_num); mutex_unlock(&sdei_events_lock); @@ -356,6 +379,10 @@ int sdei_event_disable(u32 event_num) return -ENOENT; } + spin_lock(&sdei_list_lock); + event->reenable = false; + spin_unlock(&sdei_list_lock); + if (event->type == SDEI_EVENT_TYPE_SHARED) err = sdei_api_event_disable(event->event_num); mutex_unlock(&sdei_events_lock); @@ -374,6 +401,11 @@ static int _sdei_event_unregister(struct sdei_event *event) { lockdep_assert_held(&sdei_events_lock); + spin_lock(&sdei_list_lock); + event->reregister = false; + event->reenable = false; + spin_unlock(&sdei_list_lock); + if (event->type == SDEI_EVENT_TYPE_SHARED) return sdei_api_event_unregister(event->event_num); @@ -408,6 +440,31 @@ int sdei_event_unregister(u32 event_num) } EXPORT_SYMBOL(sdei_event_unregister); +/* + * unregister events, but don't destroy them as they are re-registered by + * sdei_reregister_shared(). + */ +static int sdei_unregister_shared(void) +{ + int err = 0; + struct sdei_event *event; + + mutex_lock(&sdei_events_lock); + spin_lock(&sdei_list_lock); + list_for_each_entry(event, &sdei_list, list) { + if (event->type != SDEI_EVENT_TYPE_SHARED) + continue; + + err = _sdei_event_unregister(event); + if (err) + break; + } + spin_unlock(&sdei_list_lock); + mutex_unlock(&sdei_events_lock); + + return err; +} + static int sdei_api_event_register(u32 event_num, unsigned long entry_point, void *arg, u64 flags, u64 affinity) { @@ -465,6 +522,175 @@ int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg) } EXPORT_SYMBOL(sdei_event_register); +static int sdei_reregister_event(struct sdei_event *event) +{ + int err; + + lockdep_assert_held(&sdei_events_lock); + + err = _sdei_event_register(event); + if (err) { + pr_err("Failed to re-register event %u\n", event->event_num); + sdei_event_destroy(event); + return err; + } + + if (event->reenable) { + if (event->type == SDEI_EVENT_TYPE_SHARED) + err = sdei_api_event_enable(event->event_num); + } + + if (err) + pr_err("Failed to re-enable event %u\n", event->event_num); + + return err; +} + +static int sdei_reregister_shared(void) +{ + int err = 0; + struct sdei_event *event; + + mutex_lock(&sdei_events_lock); + spin_lock(&sdei_list_lock); + list_for_each_entry(event, &sdei_list, list) { + if (event->type != SDEI_EVENT_TYPE_SHARED) + continue; + + if (event->reregister) { + err = sdei_reregister_event(event); + if (err) + break; + } + } + spin_unlock(&sdei_list_lock); + mutex_unlock(&sdei_events_lock); + + return err; +} + +/* When entering idle, mask/unmask events for this cpu */ +static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action, + void *data) +{ + int rv; + + switch (action) { + case CPU_PM_ENTER: + rv = sdei_mask_local_cpu(); + break; + case CPU_PM_EXIT: + case CPU_PM_ENTER_FAILED: + rv = sdei_unmask_local_cpu(); + break; + default: + return NOTIFY_DONE; + } + + if (rv) + return notifier_from_errno(rv); + + return NOTIFY_OK; +} + +static struct notifier_block sdei_pm_nb = { + .notifier_call = sdei_pm_notifier, +}; + +static int sdei_device_suspend(struct device *dev) +{ + on_each_cpu(_ipi_mask_cpu, NULL, true); + + return 0; +} + +static int sdei_device_resume(struct device *dev) +{ + on_each_cpu(_ipi_unmask_cpu, NULL, true); + + return 0; +} + +/* + * We need all events to be reregistered when we resume from hibernate. + * + * The sequence is freeze->thaw. Reboot. freeze->restore. We unregister + * events during freeze, then re-register and re-enable them during thaw + * and restore. + */ +static int sdei_device_freeze(struct device *dev) +{ + int err; + + cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING); + + err = sdei_unregister_shared(); + if (err) + return err; + + return 0; +} + +static int sdei_device_thaw(struct device *dev) +{ + int err; + + /* re-register shared events */ + err = sdei_reregister_shared(); + if (err) { + pr_warn("Failed to re-register shared events...\n"); + sdei_mark_interface_broken(); + return err; + } + + err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI", + &sdei_cpuhp_up, &sdei_cpuhp_down); + if (err) + pr_warn("Failed to re-register CPU hotplug notifier...\n"); + + return err; +} + +static int sdei_device_restore(struct device *dev) +{ + int err; + + err = sdei_platform_reset(); + if (err) + return err; + + return sdei_device_thaw(dev); +} + +static const struct dev_pm_ops sdei_pm_ops = { + .suspend = sdei_device_suspend, + .resume = sdei_device_resume, + .freeze = sdei_device_freeze, + .thaw = sdei_device_thaw, + .restore = sdei_device_restore, +}; + +/* + * Mask all CPUs and unregister all events on panic, reboot or kexec. + */ +static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action, + void *data) +{ + /* + * We are going to reset the interface, after this there is no point + * doing work when we take CPUs offline. + */ + cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING); + + sdei_platform_reset(); + + return NOTIFY_OK; +} + +static struct notifier_block sdei_reboot_nb = { + .notifier_call = sdei_reboot_notifier, +}; + static void sdei_smccc_smc(unsigned long function_id, unsigned long arg0, unsigned long arg1, unsigned long arg2, unsigned long arg3, @@ -547,9 +773,36 @@ static int sdei_probe(struct platform_device *pdev) return 0; } - on_each_cpu(&_ipi_unmask_cpu, NULL, false); + err = cpu_pm_register_notifier(&sdei_pm_nb); + if (err) { + pr_warn("Failed to register CPU PM notifier...\n"); + goto error; + } + + err = register_reboot_notifier(&sdei_reboot_nb); + if (err) { + pr_warn("Failed to register reboot notifier...\n"); + goto remove_cpupm; + } + + err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI", + &sdei_cpuhp_up, &sdei_cpuhp_down); + if (err) { + pr_warn("Failed to register CPU hotplug notifier...\n"); + goto remove_reboot; + } return 0; + +remove_reboot: + unregister_reboot_notifier(&sdei_reboot_nb); + +remove_cpupm: + cpu_pm_unregister_notifier(&sdei_pm_nb); + +error: + sdei_mark_interface_broken(); + return err; } static const struct of_device_id sdei_of_match[] = { @@ -560,6 +813,7 @@ static const struct of_device_id sdei_of_match[] = { static struct platform_driver sdei_driver = { .driver = { .name = "sdei", + .pm = &sdei_pm_ops, .of_match_table = sdei_of_match, }, .probe = sdei_probe, diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 201ab7267986..87b505a48a94 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -109,6 +109,7 @@ enum cpuhp_state { CPUHP_AP_PERF_XTENSA_STARTING, CPUHP_AP_PERF_METAG_STARTING, CPUHP_AP_MIPS_OP_LOONGSON3_STARTING, + CPUHP_AP_ARM_SDEI_STARTING, CPUHP_AP_ARM_VFP_STARTING, CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING, CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING, -- cgit v1.2.3 From fa31ab77ced9fbab87fbac4fca3682009b7f9be2 Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 8 Jan 2018 15:38:15 +0000 Subject: arm64: acpi: Remove __init from acpi_psci_use_hvc() for use by SDEI SDEI inherits the 'use hvc' bit that is also used by PSCI. PSCI does all its initialisation early, SDEI does its late. Remove the __init annotation from acpi_psci_use_hvc(). Acked-by: Lorenzo Pieralisi Signed-off-by: James Morse Acked-by: Catalin Marinas Signed-off-by: Catalin Marinas --- arch/arm64/kernel/acpi.c | 2 +- include/linux/psci.h | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index b3162715ed78..252396a96c78 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -117,7 +117,7 @@ bool __init acpi_psci_present(void) } /* Whether HVC must be used instead of SMC as the PSCI conduit */ -bool __init acpi_psci_use_hvc(void) +bool acpi_psci_use_hvc(void) { return acpi_gbl_FADT.arm_boot_flags & ACPI_FADT_PSCI_USE_HVC; } diff --git a/include/linux/psci.h b/include/linux/psci.h index 6306ab10af18..f724fd8c78e8 100644 --- a/include/linux/psci.h +++ b/include/linux/psci.h @@ -47,10 +47,11 @@ static inline int psci_dt_init(void) { return 0; } #if defined(CONFIG_ARM_PSCI_FW) && defined(CONFIG_ACPI) int __init psci_acpi_init(void); bool __init acpi_psci_present(void); -bool __init acpi_psci_use_hvc(void); +bool acpi_psci_use_hvc(void); #else static inline int psci_acpi_init(void) { return 0; } static inline bool acpi_psci_present(void) { return false; } +static inline bool acpi_psci_use_hvc(void) {return false; } #endif #endif /* __LINUX_PSCI_H */ -- cgit v1.2.3