drivers: firmware: psci: Move psci to separate directory
authorUlf Hansson <ulf.hansson@linaro.org>
Wed, 10 Apr 2019 08:20:21 +0000 (10:20 +0200)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 12 Apr 2019 08:59:37 +0000 (10:59 +0200)
Some following changes extends the PSCI driver with some additional
files.  Avoid to continue cluttering the toplevel firmware directory
and first move the PSCI files into a PSCI sub-directory.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/firmware/Kconfig
drivers/firmware/Makefile
drivers/firmware/psci.c [deleted file]
drivers/firmware/psci/Kconfig [new file with mode: 0644]
drivers/firmware/psci/Makefile [new file with mode: 0644]
drivers/firmware/psci/psci.c [new file with mode: 0644]
drivers/firmware/psci/psci_checker.c [new file with mode: 0644]
drivers/firmware/psci_checker.c [deleted file]

index cac16c4b0df3eb6232b75cb7237091a5fda8f95e..7b655f6156fba922378e6ad6c32cee8399b4aef7 100644 (file)
@@ -5,20 +5,6 @@
 
 menu "Firmware Drivers"
 
-config ARM_PSCI_FW
-       bool
-
-config ARM_PSCI_CHECKER
-       bool "ARM PSCI checker"
-       depends on ARM_PSCI_FW && HOTPLUG_CPU && CPU_IDLE && !TORTURE_TEST
-       help
-         Run the PSCI checker during startup. This checks that hotplug and
-         suspend operations work correctly when using PSCI.
-
-         The torture tests may interfere with the PSCI checker by turning CPUs
-         on and off through hotplug, so for now torture tests and PSCI checker
-         are mutually exclusive.
-
 config ARM_SCMI_PROTOCOL
        bool "ARM System Control and Management Interface (SCMI) Message Protocol"
        depends on ARM || ARM64 || COMPILE_TEST
@@ -270,6 +256,7 @@ config TI_SCI_PROTOCOL
 config HAVE_ARM_SMCCC
        bool
 
+source "drivers/firmware/psci/Kconfig"
 source "drivers/firmware/broadcom/Kconfig"
 source "drivers/firmware/google/Kconfig"
 source "drivers/firmware/efi/Kconfig"
index 80feb635120fc72283da432b08ba1f6eed8aa9dd..9a3909a226820cae08c5061bf5da5c44148e8995 100644 (file)
@@ -2,8 +2,6 @@
 #
 # Makefile for the linux kernel.
 #
-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-$(CONFIG_ARM_SDE_INTERFACE)        += arm_sdei.o
@@ -25,6 +23,7 @@ CFLAGS_qcom_scm-32.o :=$(call as-instr,.arch armv7-a\n.arch_extension sec,-DREQU
 obj-$(CONFIG_TI_SCI_PROTOCOL)  += ti_sci.o
 
 obj-$(CONFIG_ARM_SCMI_PROTOCOL)        += arm_scmi/
+obj-y                          += psci/
 obj-y                          += broadcom/
 obj-y                          += meson/
 obj-$(CONFIG_GOOGLE_FIRMWARE)  += google/
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
deleted file mode 100644 (file)
index c80ec1d..0000000
+++ /dev/null
@@ -1,708 +0,0 @@
-/*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * Copyright (C) 2015 ARM Limited
- */
-
-#define pr_fmt(fmt) "psci: " fmt
-
-#include <linux/acpi.h>
-#include <linux/arm-smccc.h>
-#include <linux/cpuidle.h>
-#include <linux/errno.h>
-#include <linux/linkage.h>
-#include <linux/of.h>
-#include <linux/pm.h>
-#include <linux/printk.h>
-#include <linux/psci.h>
-#include <linux/reboot.h>
-#include <linux/slab.h>
-#include <linux/suspend.h>
-
-#include <uapi/linux/psci.h>
-
-#include <asm/cpuidle.h>
-#include <asm/cputype.h>
-#include <asm/system_misc.h>
-#include <asm/smp_plat.h>
-#include <asm/suspend.h>
-
-/*
- * While a 64-bit OS can make calls with SMC32 calling conventions, for some
- * calls it is necessary to use SMC64 to pass or return 64-bit values.
- * For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate
- * (native-width) function ID.
- */
-#ifdef CONFIG_64BIT
-#define PSCI_FN_NATIVE(version, name)  PSCI_##version##_FN64_##name
-#else
-#define PSCI_FN_NATIVE(version, name)  PSCI_##version##_FN_##name
-#endif
-
-/*
- * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
- * calls to its resident CPU, so we must avoid issuing those. We never migrate
- * a Trusted OS even if it claims to be capable of migration -- doing so will
- * require cooperation with a Trusted OS driver.
- */
-static int resident_cpu = -1;
-
-bool psci_tos_resident_on(int cpu)
-{
-       return cpu == resident_cpu;
-}
-
-struct psci_operations psci_ops = {
-       .conduit = PSCI_CONDUIT_NONE,
-       .smccc_version = SMCCC_VERSION_1_0,
-};
-
-typedef unsigned long (psci_fn)(unsigned long, unsigned long,
-                               unsigned long, unsigned long);
-static psci_fn *invoke_psci_fn;
-
-enum psci_function {
-       PSCI_FN_CPU_SUSPEND,
-       PSCI_FN_CPU_ON,
-       PSCI_FN_CPU_OFF,
-       PSCI_FN_MIGRATE,
-       PSCI_FN_MAX,
-};
-
-static u32 psci_function_id[PSCI_FN_MAX];
-
-#define PSCI_0_2_POWER_STATE_MASK              \
-                               (PSCI_0_2_POWER_STATE_ID_MASK | \
-                               PSCI_0_2_POWER_STATE_TYPE_MASK | \
-                               PSCI_0_2_POWER_STATE_AFFL_MASK)
-
-#define PSCI_1_0_EXT_POWER_STATE_MASK          \
-                               (PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
-                               PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
-
-static u32 psci_cpu_suspend_feature;
-
-static inline bool psci_has_ext_power_state(void)
-{
-       return psci_cpu_suspend_feature &
-                               PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
-}
-
-static inline bool psci_power_state_loses_context(u32 state)
-{
-       const u32 mask = psci_has_ext_power_state() ?
-                                       PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
-                                       PSCI_0_2_POWER_STATE_TYPE_MASK;
-
-       return state & mask;
-}
-
-static inline bool psci_power_state_is_valid(u32 state)
-{
-       const u32 valid_mask = psci_has_ext_power_state() ?
-                              PSCI_1_0_EXT_POWER_STATE_MASK :
-                              PSCI_0_2_POWER_STATE_MASK;
-
-       return !(state & ~valid_mask);
-}
-
-static unsigned long __invoke_psci_fn_hvc(unsigned long function_id,
-                       unsigned long arg0, unsigned long arg1,
-                       unsigned long arg2)
-{
-       struct arm_smccc_res res;
-
-       arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
-       return res.a0;
-}
-
-static unsigned long __invoke_psci_fn_smc(unsigned long function_id,
-                       unsigned long arg0, unsigned long arg1,
-                       unsigned long arg2)
-{
-       struct arm_smccc_res res;
-
-       arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
-       return res.a0;
-}
-
-static int psci_to_linux_errno(int errno)
-{
-       switch (errno) {
-       case PSCI_RET_SUCCESS:
-               return 0;
-       case PSCI_RET_NOT_SUPPORTED:
-               return -EOPNOTSUPP;
-       case PSCI_RET_INVALID_PARAMS:
-       case PSCI_RET_INVALID_ADDRESS:
-               return -EINVAL;
-       case PSCI_RET_DENIED:
-               return -EPERM;
-       };
-
-       return -EINVAL;
-}
-
-static u32 psci_get_version(void)
-{
-       return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
-}
-
-static int psci_cpu_suspend(u32 state, unsigned long entry_point)
-{
-       int err;
-       u32 fn;
-
-       fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
-       err = invoke_psci_fn(fn, state, entry_point, 0);
-       return psci_to_linux_errno(err);
-}
-
-static int psci_cpu_off(u32 state)
-{
-       int err;
-       u32 fn;
-
-       fn = psci_function_id[PSCI_FN_CPU_OFF];
-       err = invoke_psci_fn(fn, state, 0, 0);
-       return psci_to_linux_errno(err);
-}
-
-static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
-{
-       int err;
-       u32 fn;
-
-       fn = psci_function_id[PSCI_FN_CPU_ON];
-       err = invoke_psci_fn(fn, cpuid, entry_point, 0);
-       return psci_to_linux_errno(err);
-}
-
-static int psci_migrate(unsigned long cpuid)
-{
-       int err;
-       u32 fn;
-
-       fn = psci_function_id[PSCI_FN_MIGRATE];
-       err = invoke_psci_fn(fn, cpuid, 0, 0);
-       return psci_to_linux_errno(err);
-}
-
-static int psci_affinity_info(unsigned long target_affinity,
-               unsigned long lowest_affinity_level)
-{
-       return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
-                             target_affinity, lowest_affinity_level, 0);
-}
-
-static int psci_migrate_info_type(void)
-{
-       return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
-}
-
-static unsigned long psci_migrate_info_up_cpu(void)
-{
-       return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
-                             0, 0, 0);
-}
-
-static void set_conduit(enum psci_conduit conduit)
-{
-       switch (conduit) {
-       case PSCI_CONDUIT_HVC:
-               invoke_psci_fn = __invoke_psci_fn_hvc;
-               break;
-       case PSCI_CONDUIT_SMC:
-               invoke_psci_fn = __invoke_psci_fn_smc;
-               break;
-       default:
-               WARN(1, "Unexpected PSCI conduit %d\n", conduit);
-       }
-
-       psci_ops.conduit = conduit;
-}
-
-static int get_set_conduit_method(struct device_node *np)
-{
-       const char *method;
-
-       pr_info("probing for conduit method from DT.\n");
-
-       if (of_property_read_string(np, "method", &method)) {
-               pr_warn("missing \"method\" property\n");
-               return -ENXIO;
-       }
-
-       if (!strcmp("hvc", method)) {
-               set_conduit(PSCI_CONDUIT_HVC);
-       } else if (!strcmp("smc", method)) {
-               set_conduit(PSCI_CONDUIT_SMC);
-       } else {
-               pr_warn("invalid \"method\" property: %s\n", method);
-               return -EINVAL;
-       }
-       return 0;
-}
-
-static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
-{
-       invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
-}
-
-static void psci_sys_poweroff(void)
-{
-       invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
-}
-
-static int __init psci_features(u32 psci_func_id)
-{
-       return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
-                             psci_func_id, 0, 0);
-}
-
-#ifdef CONFIG_CPU_IDLE
-static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
-
-static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu)
-{
-       int i, ret, count = 0;
-       u32 *psci_states;
-       struct device_node *state_node;
-
-       /* Count idle states */
-       while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
-                                             count))) {
-               count++;
-               of_node_put(state_node);
-       }
-
-       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;
-
-               state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
-
-               ret = of_property_read_u32(state_node,
-                                          "arm,psci-suspend-param",
-                                          &state);
-               if (ret) {
-                       pr_warn(" * %pOF missing arm,psci-suspend-param property\n",
-                               state_node);
-                       of_node_put(state_node);
-                       goto free_mem;
-               }
-
-               of_node_put(state_node);
-               pr_debug("psci-power-state %#x index %d\n", state, i);
-               if (!psci_power_state_is_valid(state)) {
-                       pr_warn("Invalid PSCI power state %#x\n", state);
-                       ret = -EINVAL;
-                       goto free_mem;
-               }
-               psci_states[i] = state;
-       }
-       /* Idle states parsed correctly, initialize per-cpu pointer */
-       per_cpu(psci_power_state, cpu) = psci_states;
-       return 0;
-
-free_mem:
-       kfree(psci_states);
-       return ret;
-}
-
-#ifdef CONFIG_ACPI
-#include <acpi/processor.h>
-
-static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
-{
-       int i, count;
-       u32 *psci_states;
-       struct acpi_lpi_state *lpi;
-       struct acpi_processor *pr = per_cpu(processors, cpu);
-
-       if (unlikely(!pr || !pr->flags.has_lpi))
-               return -EINVAL;
-
-       count = pr->power.count - 1;
-       if (count <= 0)
-               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];
-               /*
-                * Only bits[31:0] represent a PSCI power_state while
-                * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification
-                */
-               state = lpi->address;
-               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;
-}
-#else
-static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
-{
-       return -EINVAL;
-}
-#endif
-
-int psci_cpu_init_idle(unsigned int cpu)
-{
-       struct device_node *cpu_node;
-       int ret;
-
-       /*
-        * 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;
-
-       if (!acpi_disabled)
-               return psci_acpi_cpu_init_idle(cpu);
-
-       cpu_node = of_get_cpu_node(cpu, NULL);
-       if (!cpu_node)
-               return -ENODEV;
-
-       ret = psci_dt_cpu_init_idle(cpu_node, cpu);
-
-       of_node_put(cpu_node);
-
-       return ret;
-}
-
-static int psci_suspend_finisher(unsigned long index)
-{
-       u32 *state = __this_cpu_read(psci_power_state);
-
-       return psci_ops.cpu_suspend(state[index - 1],
-                                   __pa_symbol(cpu_resume));
-}
-
-int psci_cpu_suspend_enter(unsigned long index)
-{
-       int ret;
-       u32 *state = __this_cpu_read(psci_power_state);
-       /*
-        * idle state index 0 corresponds to wfi, should never be called
-        * from the cpu_suspend operations
-        */
-       if (WARN_ON_ONCE(!index))
-               return -EINVAL;
-
-       if (!psci_power_state_loses_context(state[index - 1]))
-               ret = psci_ops.cpu_suspend(state[index - 1], 0);
-       else
-               ret = cpu_suspend(index, psci_suspend_finisher);
-
-       return ret;
-}
-
-/* ARM specific CPU idle operations */
-#ifdef CONFIG_ARM
-static const struct cpuidle_ops psci_cpuidle_ops __initconst = {
-       .suspend = psci_cpu_suspend_enter,
-       .init = psci_dt_cpu_init_idle,
-};
-
-CPUIDLE_METHOD_OF_DECLARE(psci, "psci", &psci_cpuidle_ops);
-#endif
-#endif
-
-static int psci_system_suspend(unsigned long unused)
-{
-       return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
-                             __pa_symbol(cpu_resume), 0, 0);
-}
-
-static int psci_system_suspend_enter(suspend_state_t state)
-{
-       return cpu_suspend(0, psci_system_suspend);
-}
-
-static const struct platform_suspend_ops psci_suspend_ops = {
-       .valid          = suspend_valid_only_mem,
-       .enter          = psci_system_suspend_enter,
-};
-
-static void __init psci_init_system_suspend(void)
-{
-       int ret;
-
-       if (!IS_ENABLED(CONFIG_SUSPEND))
-               return;
-
-       ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
-
-       if (ret != PSCI_RET_NOT_SUPPORTED)
-               suspend_set_ops(&psci_suspend_ops);
-}
-
-static void __init psci_init_cpu_suspend(void)
-{
-       int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);
-
-       if (feature != PSCI_RET_NOT_SUPPORTED)
-               psci_cpu_suspend_feature = feature;
-}
-
-/*
- * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
- * return DENIED (which would be fatal).
- */
-static void __init psci_init_migrate(void)
-{
-       unsigned long cpuid;
-       int type, cpu = -1;
-
-       type = psci_ops.migrate_info_type();
-
-       if (type == PSCI_0_2_TOS_MP) {
-               pr_info("Trusted OS migration not required\n");
-               return;
-       }
-
-       if (type == PSCI_RET_NOT_SUPPORTED) {
-               pr_info("MIGRATE_INFO_TYPE not supported.\n");
-               return;
-       }
-
-       if (type != PSCI_0_2_TOS_UP_MIGRATE &&
-           type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
-               pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
-               return;
-       }
-
-       cpuid = psci_migrate_info_up_cpu();
-       if (cpuid & ~MPIDR_HWID_BITMASK) {
-               pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
-                       cpuid);
-               return;
-       }
-
-       cpu = get_logical_index(cpuid);
-       resident_cpu = cpu >= 0 ? cpu : -1;
-
-       pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
-}
-
-static void __init psci_init_smccc(void)
-{
-       u32 ver = ARM_SMCCC_VERSION_1_0;
-       int feature;
-
-       feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
-
-       if (feature != PSCI_RET_NOT_SUPPORTED) {
-               u32 ret;
-               ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
-               if (ret == ARM_SMCCC_VERSION_1_1) {
-                       psci_ops.smccc_version = SMCCC_VERSION_1_1;
-                       ver = ret;
-               }
-       }
-
-       /*
-        * Conveniently, the SMCCC and PSCI versions are encoded the
-        * same way. No, this isn't accidental.
-        */
-       pr_info("SMC Calling Convention v%d.%d\n",
-               PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
-
-}
-
-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;
-
-       psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
-       psci_ops.cpu_off = psci_cpu_off;
-
-       psci_function_id[PSCI_FN_CPU_ON] = PSCI_FN_NATIVE(0_2, CPU_ON);
-       psci_ops.cpu_on = psci_cpu_on;
-
-       psci_function_id[PSCI_FN_MIGRATE] = PSCI_FN_NATIVE(0_2, MIGRATE);
-       psci_ops.migrate = psci_migrate;
-
-       psci_ops.affinity_info = psci_affinity_info;
-
-       psci_ops.migrate_info_type = psci_migrate_info_type;
-
-       arm_pm_restart = psci_sys_reset;
-
-       pm_power_off = psci_sys_poweroff;
-}
-
-/*
- * Probe function for PSCI firmware versions >= 0.2
- */
-static int __init psci_probe(void)
-{
-       u32 ver = psci_get_version();
-
-       pr_info("PSCIv%d.%d detected in firmware.\n",
-                       PSCI_VERSION_MAJOR(ver),
-                       PSCI_VERSION_MINOR(ver));
-
-       if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
-               pr_err("Conflicting PSCI version detected.\n");
-               return -EINVAL;
-       }
-
-       psci_0_2_set_functions();
-
-       psci_init_migrate();
-
-       if (PSCI_VERSION_MAJOR(ver) >= 1) {
-               psci_init_smccc();
-               psci_init_cpu_suspend();
-               psci_init_system_suspend();
-       }
-
-       return 0;
-}
-
-typedef int (*psci_initcall_t)(const struct device_node *);
-
-/*
- * PSCI init function for PSCI versions >=0.2
- *
- * Probe based on PSCI PSCI_VERSION function
- */
-static int __init psci_0_2_init(struct device_node *np)
-{
-       int err;
-
-       err = get_set_conduit_method(np);
-
-       if (err)
-               goto out_put_node;
-       /*
-        * Starting with v0.2, the PSCI specification introduced a call
-        * (PSCI_VERSION) that allows probing the firmware version, so
-        * that PSCI function IDs and version specific initialization
-        * can be carried out according to the specific version reported
-        * by firmware
-        */
-       err = psci_probe();
-
-out_put_node:
-       of_node_put(np);
-       return err;
-}
-
-/*
- * PSCI < v0.2 get PSCI Function IDs via DT.
- */
-static int __init psci_0_1_init(struct device_node *np)
-{
-       u32 id;
-       int err;
-
-       err = get_set_conduit_method(np);
-
-       if (err)
-               goto out_put_node;
-
-       pr_info("Using PSCI v0.1 Function IDs from DT\n");
-
-       if (!of_property_read_u32(np, "cpu_suspend", &id)) {
-               psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
-               psci_ops.cpu_suspend = psci_cpu_suspend;
-       }
-
-       if (!of_property_read_u32(np, "cpu_off", &id)) {
-               psci_function_id[PSCI_FN_CPU_OFF] = id;
-               psci_ops.cpu_off = psci_cpu_off;
-       }
-
-       if (!of_property_read_u32(np, "cpu_on", &id)) {
-               psci_function_id[PSCI_FN_CPU_ON] = id;
-               psci_ops.cpu_on = psci_cpu_on;
-       }
-
-       if (!of_property_read_u32(np, "migrate", &id)) {
-               psci_function_id[PSCI_FN_MIGRATE] = id;
-               psci_ops.migrate = psci_migrate;
-       }
-
-out_put_node:
-       of_node_put(np);
-       return err;
-}
-
-static const struct of_device_id psci_of_match[] __initconst = {
-       { .compatible = "arm,psci",     .data = psci_0_1_init},
-       { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
-       { .compatible = "arm,psci-1.0", .data = psci_0_2_init},
-       {},
-};
-
-int __init psci_dt_init(void)
-{
-       struct device_node *np;
-       const struct of_device_id *matched_np;
-       psci_initcall_t init_fn;
-
-       np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
-
-       if (!np || !of_device_is_available(np))
-               return -ENODEV;
-
-       init_fn = (psci_initcall_t)matched_np->data;
-       return init_fn(np);
-}
-
-#ifdef CONFIG_ACPI
-/*
- * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
- * explicitly clarified in SBBR
- */
-int __init psci_acpi_init(void)
-{
-       if (!acpi_psci_present()) {
-               pr_info("is not implemented in ACPI.\n");
-               return -EOPNOTSUPP;
-       }
-
-       pr_info("probing for conduit method from ACPI.\n");
-
-       if (acpi_psci_use_hvc())
-               set_conduit(PSCI_CONDUIT_HVC);
-       else
-               set_conduit(PSCI_CONDUIT_SMC);
-
-       return psci_probe();
-}
-#endif
diff --git a/drivers/firmware/psci/Kconfig b/drivers/firmware/psci/Kconfig
new file mode 100644 (file)
index 0000000..26a3b32
--- /dev/null
@@ -0,0 +1,13 @@
+config ARM_PSCI_FW
+       bool
+
+config ARM_PSCI_CHECKER
+       bool "ARM PSCI checker"
+       depends on ARM_PSCI_FW && HOTPLUG_CPU && CPU_IDLE && !TORTURE_TEST
+       help
+         Run the PSCI checker during startup. This checks that hotplug and
+         suspend operations work correctly when using PSCI.
+
+         The torture tests may interfere with the PSCI checker by turning CPUs
+         on and off through hotplug, so for now torture tests and PSCI checker
+         are mutually exclusive.
diff --git a/drivers/firmware/psci/Makefile b/drivers/firmware/psci/Makefile
new file mode 100644 (file)
index 0000000..1956b88
--- /dev/null
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+obj-$(CONFIG_ARM_PSCI_FW)      += psci.o
+obj-$(CONFIG_ARM_PSCI_CHECKER) += psci_checker.o
diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
new file mode 100644 (file)
index 0000000..c80ec1d
--- /dev/null
@@ -0,0 +1,708 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2015 ARM Limited
+ */
+
+#define pr_fmt(fmt) "psci: " fmt
+
+#include <linux/acpi.h>
+#include <linux/arm-smccc.h>
+#include <linux/cpuidle.h>
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/printk.h>
+#include <linux/psci.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+
+#include <uapi/linux/psci.h>
+
+#include <asm/cpuidle.h>
+#include <asm/cputype.h>
+#include <asm/system_misc.h>
+#include <asm/smp_plat.h>
+#include <asm/suspend.h>
+
+/*
+ * While a 64-bit OS can make calls with SMC32 calling conventions, for some
+ * calls it is necessary to use SMC64 to pass or return 64-bit values.
+ * For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate
+ * (native-width) function ID.
+ */
+#ifdef CONFIG_64BIT
+#define PSCI_FN_NATIVE(version, name)  PSCI_##version##_FN64_##name
+#else
+#define PSCI_FN_NATIVE(version, name)  PSCI_##version##_FN_##name
+#endif
+
+/*
+ * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
+ * calls to its resident CPU, so we must avoid issuing those. We never migrate
+ * a Trusted OS even if it claims to be capable of migration -- doing so will
+ * require cooperation with a Trusted OS driver.
+ */
+static int resident_cpu = -1;
+
+bool psci_tos_resident_on(int cpu)
+{
+       return cpu == resident_cpu;
+}
+
+struct psci_operations psci_ops = {
+       .conduit = PSCI_CONDUIT_NONE,
+       .smccc_version = SMCCC_VERSION_1_0,
+};
+
+typedef unsigned long (psci_fn)(unsigned long, unsigned long,
+                               unsigned long, unsigned long);
+static psci_fn *invoke_psci_fn;
+
+enum psci_function {
+       PSCI_FN_CPU_SUSPEND,
+       PSCI_FN_CPU_ON,
+       PSCI_FN_CPU_OFF,
+       PSCI_FN_MIGRATE,
+       PSCI_FN_MAX,
+};
+
+static u32 psci_function_id[PSCI_FN_MAX];
+
+#define PSCI_0_2_POWER_STATE_MASK              \
+                               (PSCI_0_2_POWER_STATE_ID_MASK | \
+                               PSCI_0_2_POWER_STATE_TYPE_MASK | \
+                               PSCI_0_2_POWER_STATE_AFFL_MASK)
+
+#define PSCI_1_0_EXT_POWER_STATE_MASK          \
+                               (PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
+                               PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
+
+static u32 psci_cpu_suspend_feature;
+
+static inline bool psci_has_ext_power_state(void)
+{
+       return psci_cpu_suspend_feature &
+                               PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
+}
+
+static inline bool psci_power_state_loses_context(u32 state)
+{
+       const u32 mask = psci_has_ext_power_state() ?
+                                       PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
+                                       PSCI_0_2_POWER_STATE_TYPE_MASK;
+
+       return state & mask;
+}
+
+static inline bool psci_power_state_is_valid(u32 state)
+{
+       const u32 valid_mask = psci_has_ext_power_state() ?
+                              PSCI_1_0_EXT_POWER_STATE_MASK :
+                              PSCI_0_2_POWER_STATE_MASK;
+
+       return !(state & ~valid_mask);
+}
+
+static unsigned long __invoke_psci_fn_hvc(unsigned long function_id,
+                       unsigned long arg0, unsigned long arg1,
+                       unsigned long arg2)
+{
+       struct arm_smccc_res res;
+
+       arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
+       return res.a0;
+}
+
+static unsigned long __invoke_psci_fn_smc(unsigned long function_id,
+                       unsigned long arg0, unsigned long arg1,
+                       unsigned long arg2)
+{
+       struct arm_smccc_res res;
+
+       arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
+       return res.a0;
+}
+
+static int psci_to_linux_errno(int errno)
+{
+       switch (errno) {
+       case PSCI_RET_SUCCESS:
+               return 0;
+       case PSCI_RET_NOT_SUPPORTED:
+               return -EOPNOTSUPP;
+       case PSCI_RET_INVALID_PARAMS:
+       case PSCI_RET_INVALID_ADDRESS:
+               return -EINVAL;
+       case PSCI_RET_DENIED:
+               return -EPERM;
+       };
+
+       return -EINVAL;
+}
+
+static u32 psci_get_version(void)
+{
+       return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
+}
+
+static int psci_cpu_suspend(u32 state, unsigned long entry_point)
+{
+       int err;
+       u32 fn;
+
+       fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
+       err = invoke_psci_fn(fn, state, entry_point, 0);
+       return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_off(u32 state)
+{
+       int err;
+       u32 fn;
+
+       fn = psci_function_id[PSCI_FN_CPU_OFF];
+       err = invoke_psci_fn(fn, state, 0, 0);
+       return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
+{
+       int err;
+       u32 fn;
+
+       fn = psci_function_id[PSCI_FN_CPU_ON];
+       err = invoke_psci_fn(fn, cpuid, entry_point, 0);
+       return psci_to_linux_errno(err);
+}
+
+static int psci_migrate(unsigned long cpuid)
+{
+       int err;
+       u32 fn;
+
+       fn = psci_function_id[PSCI_FN_MIGRATE];
+       err = invoke_psci_fn(fn, cpuid, 0, 0);
+       return psci_to_linux_errno(err);
+}
+
+static int psci_affinity_info(unsigned long target_affinity,
+               unsigned long lowest_affinity_level)
+{
+       return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
+                             target_affinity, lowest_affinity_level, 0);
+}
+
+static int psci_migrate_info_type(void)
+{
+       return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
+}
+
+static unsigned long psci_migrate_info_up_cpu(void)
+{
+       return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
+                             0, 0, 0);
+}
+
+static void set_conduit(enum psci_conduit conduit)
+{
+       switch (conduit) {
+       case PSCI_CONDUIT_HVC:
+               invoke_psci_fn = __invoke_psci_fn_hvc;
+               break;
+       case PSCI_CONDUIT_SMC:
+               invoke_psci_fn = __invoke_psci_fn_smc;
+               break;
+       default:
+               WARN(1, "Unexpected PSCI conduit %d\n", conduit);
+       }
+
+       psci_ops.conduit = conduit;
+}
+
+static int get_set_conduit_method(struct device_node *np)
+{
+       const char *method;
+
+       pr_info("probing for conduit method from DT.\n");
+
+       if (of_property_read_string(np, "method", &method)) {
+               pr_warn("missing \"method\" property\n");
+               return -ENXIO;
+       }
+
+       if (!strcmp("hvc", method)) {
+               set_conduit(PSCI_CONDUIT_HVC);
+       } else if (!strcmp("smc", method)) {
+               set_conduit(PSCI_CONDUIT_SMC);
+       } else {
+               pr_warn("invalid \"method\" property: %s\n", method);
+               return -EINVAL;
+       }
+       return 0;
+}
+
+static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
+{
+       invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
+}
+
+static void psci_sys_poweroff(void)
+{
+       invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
+}
+
+static int __init psci_features(u32 psci_func_id)
+{
+       return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
+                             psci_func_id, 0, 0);
+}
+
+#ifdef CONFIG_CPU_IDLE
+static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
+
+static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu)
+{
+       int i, ret, count = 0;
+       u32 *psci_states;
+       struct device_node *state_node;
+
+       /* Count idle states */
+       while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
+                                             count))) {
+               count++;
+               of_node_put(state_node);
+       }
+
+       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;
+
+               state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
+
+               ret = of_property_read_u32(state_node,
+                                          "arm,psci-suspend-param",
+                                          &state);
+               if (ret) {
+                       pr_warn(" * %pOF missing arm,psci-suspend-param property\n",
+                               state_node);
+                       of_node_put(state_node);
+                       goto free_mem;
+               }
+
+               of_node_put(state_node);
+               pr_debug("psci-power-state %#x index %d\n", state, i);
+               if (!psci_power_state_is_valid(state)) {
+                       pr_warn("Invalid PSCI power state %#x\n", state);
+                       ret = -EINVAL;
+                       goto free_mem;
+               }
+               psci_states[i] = state;
+       }
+       /* Idle states parsed correctly, initialize per-cpu pointer */
+       per_cpu(psci_power_state, cpu) = psci_states;
+       return 0;
+
+free_mem:
+       kfree(psci_states);
+       return ret;
+}
+
+#ifdef CONFIG_ACPI
+#include <acpi/processor.h>
+
+static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
+{
+       int i, count;
+       u32 *psci_states;
+       struct acpi_lpi_state *lpi;
+       struct acpi_processor *pr = per_cpu(processors, cpu);
+
+       if (unlikely(!pr || !pr->flags.has_lpi))
+               return -EINVAL;
+
+       count = pr->power.count - 1;
+       if (count <= 0)
+               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];
+               /*
+                * Only bits[31:0] represent a PSCI power_state while
+                * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification
+                */
+               state = lpi->address;
+               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;
+}
+#else
+static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
+{
+       return -EINVAL;
+}
+#endif
+
+int psci_cpu_init_idle(unsigned int cpu)
+{
+       struct device_node *cpu_node;
+       int ret;
+
+       /*
+        * 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;
+
+       if (!acpi_disabled)
+               return psci_acpi_cpu_init_idle(cpu);
+
+       cpu_node = of_get_cpu_node(cpu, NULL);
+       if (!cpu_node)
+               return -ENODEV;
+
+       ret = psci_dt_cpu_init_idle(cpu_node, cpu);
+
+       of_node_put(cpu_node);
+
+       return ret;
+}
+
+static int psci_suspend_finisher(unsigned long index)
+{
+       u32 *state = __this_cpu_read(psci_power_state);
+
+       return psci_ops.cpu_suspend(state[index - 1],
+                                   __pa_symbol(cpu_resume));
+}
+
+int psci_cpu_suspend_enter(unsigned long index)
+{
+       int ret;
+       u32 *state = __this_cpu_read(psci_power_state);
+       /*
+        * idle state index 0 corresponds to wfi, should never be called
+        * from the cpu_suspend operations
+        */
+       if (WARN_ON_ONCE(!index))
+               return -EINVAL;
+
+       if (!psci_power_state_loses_context(state[index - 1]))
+               ret = psci_ops.cpu_suspend(state[index - 1], 0);
+       else
+               ret = cpu_suspend(index, psci_suspend_finisher);
+
+       return ret;
+}
+
+/* ARM specific CPU idle operations */
+#ifdef CONFIG_ARM
+static const struct cpuidle_ops psci_cpuidle_ops __initconst = {
+       .suspend = psci_cpu_suspend_enter,
+       .init = psci_dt_cpu_init_idle,
+};
+
+CPUIDLE_METHOD_OF_DECLARE(psci, "psci", &psci_cpuidle_ops);
+#endif
+#endif
+
+static int psci_system_suspend(unsigned long unused)
+{
+       return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
+                             __pa_symbol(cpu_resume), 0, 0);
+}
+
+static int psci_system_suspend_enter(suspend_state_t state)
+{
+       return cpu_suspend(0, psci_system_suspend);
+}
+
+static const struct platform_suspend_ops psci_suspend_ops = {
+       .valid          = suspend_valid_only_mem,
+       .enter          = psci_system_suspend_enter,
+};
+
+static void __init psci_init_system_suspend(void)
+{
+       int ret;
+
+       if (!IS_ENABLED(CONFIG_SUSPEND))
+               return;
+
+       ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
+
+       if (ret != PSCI_RET_NOT_SUPPORTED)
+               suspend_set_ops(&psci_suspend_ops);
+}
+
+static void __init psci_init_cpu_suspend(void)
+{
+       int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);
+
+       if (feature != PSCI_RET_NOT_SUPPORTED)
+               psci_cpu_suspend_feature = feature;
+}
+
+/*
+ * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
+ * return DENIED (which would be fatal).
+ */
+static void __init psci_init_migrate(void)
+{
+       unsigned long cpuid;
+       int type, cpu = -1;
+
+       type = psci_ops.migrate_info_type();
+
+       if (type == PSCI_0_2_TOS_MP) {
+               pr_info("Trusted OS migration not required\n");
+               return;
+       }
+
+       if (type == PSCI_RET_NOT_SUPPORTED) {
+               pr_info("MIGRATE_INFO_TYPE not supported.\n");
+               return;
+       }
+
+       if (type != PSCI_0_2_TOS_UP_MIGRATE &&
+           type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
+               pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
+               return;
+       }
+
+       cpuid = psci_migrate_info_up_cpu();
+       if (cpuid & ~MPIDR_HWID_BITMASK) {
+               pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
+                       cpuid);
+               return;
+       }
+
+       cpu = get_logical_index(cpuid);
+       resident_cpu = cpu >= 0 ? cpu : -1;
+
+       pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
+}
+
+static void __init psci_init_smccc(void)
+{
+       u32 ver = ARM_SMCCC_VERSION_1_0;
+       int feature;
+
+       feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
+
+       if (feature != PSCI_RET_NOT_SUPPORTED) {
+               u32 ret;
+               ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
+               if (ret == ARM_SMCCC_VERSION_1_1) {
+                       psci_ops.smccc_version = SMCCC_VERSION_1_1;
+                       ver = ret;
+               }
+       }
+
+       /*
+        * Conveniently, the SMCCC and PSCI versions are encoded the
+        * same way. No, this isn't accidental.
+        */
+       pr_info("SMC Calling Convention v%d.%d\n",
+               PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
+
+}
+
+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;
+
+       psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
+       psci_ops.cpu_off = psci_cpu_off;
+
+       psci_function_id[PSCI_FN_CPU_ON] = PSCI_FN_NATIVE(0_2, CPU_ON);
+       psci_ops.cpu_on = psci_cpu_on;
+
+       psci_function_id[PSCI_FN_MIGRATE] = PSCI_FN_NATIVE(0_2, MIGRATE);
+       psci_ops.migrate = psci_migrate;
+
+       psci_ops.affinity_info = psci_affinity_info;
+
+       psci_ops.migrate_info_type = psci_migrate_info_type;
+
+       arm_pm_restart = psci_sys_reset;
+
+       pm_power_off = psci_sys_poweroff;
+}
+
+/*
+ * Probe function for PSCI firmware versions >= 0.2
+ */
+static int __init psci_probe(void)
+{
+       u32 ver = psci_get_version();
+
+       pr_info("PSCIv%d.%d detected in firmware.\n",
+                       PSCI_VERSION_MAJOR(ver),
+                       PSCI_VERSION_MINOR(ver));
+
+       if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
+               pr_err("Conflicting PSCI version detected.\n");
+               return -EINVAL;
+       }
+
+       psci_0_2_set_functions();
+
+       psci_init_migrate();
+
+       if (PSCI_VERSION_MAJOR(ver) >= 1) {
+               psci_init_smccc();
+               psci_init_cpu_suspend();
+               psci_init_system_suspend();
+       }
+
+       return 0;
+}
+
+typedef int (*psci_initcall_t)(const struct device_node *);
+
+/*
+ * PSCI init function for PSCI versions >=0.2
+ *
+ * Probe based on PSCI PSCI_VERSION function
+ */
+static int __init psci_0_2_init(struct device_node *np)
+{
+       int err;
+
+       err = get_set_conduit_method(np);
+
+       if (err)
+               goto out_put_node;
+       /*
+        * Starting with v0.2, the PSCI specification introduced a call
+        * (PSCI_VERSION) that allows probing the firmware version, so
+        * that PSCI function IDs and version specific initialization
+        * can be carried out according to the specific version reported
+        * by firmware
+        */
+       err = psci_probe();
+
+out_put_node:
+       of_node_put(np);
+       return err;
+}
+
+/*
+ * PSCI < v0.2 get PSCI Function IDs via DT.
+ */
+static int __init psci_0_1_init(struct device_node *np)
+{
+       u32 id;
+       int err;
+
+       err = get_set_conduit_method(np);
+
+       if (err)
+               goto out_put_node;
+
+       pr_info("Using PSCI v0.1 Function IDs from DT\n");
+
+       if (!of_property_read_u32(np, "cpu_suspend", &id)) {
+               psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
+               psci_ops.cpu_suspend = psci_cpu_suspend;
+       }
+
+       if (!of_property_read_u32(np, "cpu_off", &id)) {
+               psci_function_id[PSCI_FN_CPU_OFF] = id;
+               psci_ops.cpu_off = psci_cpu_off;
+       }
+
+       if (!of_property_read_u32(np, "cpu_on", &id)) {
+               psci_function_id[PSCI_FN_CPU_ON] = id;
+               psci_ops.cpu_on = psci_cpu_on;
+       }
+
+       if (!of_property_read_u32(np, "migrate", &id)) {
+               psci_function_id[PSCI_FN_MIGRATE] = id;
+               psci_ops.migrate = psci_migrate;
+       }
+
+out_put_node:
+       of_node_put(np);
+       return err;
+}
+
+static const struct of_device_id psci_of_match[] __initconst = {
+       { .compatible = "arm,psci",     .data = psci_0_1_init},
+       { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
+       { .compatible = "arm,psci-1.0", .data = psci_0_2_init},
+       {},
+};
+
+int __init psci_dt_init(void)
+{
+       struct device_node *np;
+       const struct of_device_id *matched_np;
+       psci_initcall_t init_fn;
+
+       np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
+
+       if (!np || !of_device_is_available(np))
+               return -ENODEV;
+
+       init_fn = (psci_initcall_t)matched_np->data;
+       return init_fn(np);
+}
+
+#ifdef CONFIG_ACPI
+/*
+ * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
+ * explicitly clarified in SBBR
+ */
+int __init psci_acpi_init(void)
+{
+       if (!acpi_psci_present()) {
+               pr_info("is not implemented in ACPI.\n");
+               return -EOPNOTSUPP;
+       }
+
+       pr_info("probing for conduit method from ACPI.\n");
+
+       if (acpi_psci_use_hvc())
+               set_conduit(PSCI_CONDUIT_HVC);
+       else
+               set_conduit(PSCI_CONDUIT_SMC);
+
+       return psci_probe();
+}
+#endif
diff --git a/drivers/firmware/psci/psci_checker.c b/drivers/firmware/psci/psci_checker.c
new file mode 100644 (file)
index 0000000..3469436
--- /dev/null
@@ -0,0 +1,505 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2016 ARM Limited
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/atomic.h>
+#include <linux/completion.h>
+#include <linux/cpu.h>
+#include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <uapi/linux/sched/types.h>
+#include <linux/module.h>
+#include <linux/preempt.h>
+#include <linux/psci.h>
+#include <linux/slab.h>
+#include <linux/tick.h>
+#include <linux/topology.h>
+
+#include <asm/cpuidle.h>
+
+#include <uapi/linux/psci.h>
+
+#define NUM_SUSPEND_CYCLE (10)
+
+static unsigned int nb_available_cpus;
+static int tos_resident_cpu = -1;
+
+static atomic_t nb_active_threads;
+static struct completion suspend_threads_started =
+       COMPLETION_INITIALIZER(suspend_threads_started);
+static struct completion suspend_threads_done =
+       COMPLETION_INITIALIZER(suspend_threads_done);
+
+/*
+ * We assume that PSCI operations are used if they are available. This is not
+ * necessarily true on arm64, since the decision is based on the
+ * "enable-method" property of each CPU in the DT, but given that there is no
+ * arch-specific way to check this, we assume that the DT is sensible.
+ */
+static int psci_ops_check(void)
+{
+       int migrate_type = -1;
+       int cpu;
+
+       if (!(psci_ops.cpu_off && psci_ops.cpu_on && psci_ops.cpu_suspend)) {
+               pr_warn("Missing PSCI operations, aborting tests\n");
+               return -EOPNOTSUPP;
+       }
+
+       if (psci_ops.migrate_info_type)
+               migrate_type = psci_ops.migrate_info_type();
+
+       if (migrate_type == PSCI_0_2_TOS_UP_MIGRATE ||
+           migrate_type == PSCI_0_2_TOS_UP_NO_MIGRATE) {
+               /* There is a UP Trusted OS, find on which core it resides. */
+               for_each_online_cpu(cpu)
+                       if (psci_tos_resident_on(cpu)) {
+                               tos_resident_cpu = cpu;
+                               break;
+                       }
+               if (tos_resident_cpu == -1)
+                       pr_warn("UP Trusted OS resides on no online CPU\n");
+       }
+
+       return 0;
+}
+
+/*
+ * offlined_cpus is a temporary array but passing it as an argument avoids
+ * multiple allocations.
+ */
+static unsigned int down_and_up_cpus(const struct cpumask *cpus,
+                                    struct cpumask *offlined_cpus)
+{
+       int cpu;
+       int err = 0;
+
+       cpumask_clear(offlined_cpus);
+
+       /* Try to power down all CPUs in the mask. */
+       for_each_cpu(cpu, cpus) {
+               int ret = cpu_down(cpu);
+
+               /*
+                * cpu_down() checks the number of online CPUs before the TOS
+                * resident CPU.
+                */
+               if (cpumask_weight(offlined_cpus) + 1 == nb_available_cpus) {
+                       if (ret != -EBUSY) {
+                               pr_err("Unexpected return code %d while trying "
+                                      "to power down last online CPU %d\n",
+                                      ret, cpu);
+                               ++err;
+                       }
+               } else if (cpu == tos_resident_cpu) {
+                       if (ret != -EPERM) {
+                               pr_err("Unexpected return code %d while trying "
+                                      "to power down TOS resident CPU %d\n",
+                                      ret, cpu);
+                               ++err;
+                       }
+               } else if (ret != 0) {
+                       pr_err("Error occurred (%d) while trying "
+                              "to power down CPU %d\n", ret, cpu);
+                       ++err;
+               }
+
+               if (ret == 0)
+                       cpumask_set_cpu(cpu, offlined_cpus);
+       }
+
+       /* Try to power up all the CPUs that have been offlined. */
+       for_each_cpu(cpu, offlined_cpus) {
+               int ret = cpu_up(cpu);
+
+               if (ret != 0) {
+                       pr_err("Error occurred (%d) while trying "
+                              "to power up CPU %d\n", ret, cpu);
+                       ++err;
+               } else {
+                       cpumask_clear_cpu(cpu, offlined_cpus);
+               }
+       }
+
+       /*
+        * Something went bad at some point and some CPUs could not be turned
+        * back on.
+        */
+       WARN_ON(!cpumask_empty(offlined_cpus) ||
+               num_online_cpus() != nb_available_cpus);
+
+       return err;
+}
+
+static void free_cpu_groups(int num, cpumask_var_t **pcpu_groups)
+{
+       int i;
+       cpumask_var_t *cpu_groups = *pcpu_groups;
+
+       for (i = 0; i < num; ++i)
+               free_cpumask_var(cpu_groups[i]);
+       kfree(cpu_groups);
+}
+
+static int alloc_init_cpu_groups(cpumask_var_t **pcpu_groups)
+{
+       int num_groups = 0;
+       cpumask_var_t tmp, *cpu_groups;
+
+       if (!alloc_cpumask_var(&tmp, GFP_KERNEL))
+               return -ENOMEM;
+
+       cpu_groups = kcalloc(nb_available_cpus, sizeof(cpu_groups),
+                            GFP_KERNEL);
+       if (!cpu_groups)
+               return -ENOMEM;
+
+       cpumask_copy(tmp, cpu_online_mask);
+
+       while (!cpumask_empty(tmp)) {
+               const struct cpumask *cpu_group =
+                       topology_core_cpumask(cpumask_any(tmp));
+
+               if (!alloc_cpumask_var(&cpu_groups[num_groups], GFP_KERNEL)) {
+                       free_cpu_groups(num_groups, &cpu_groups);
+                       return -ENOMEM;
+               }
+               cpumask_copy(cpu_groups[num_groups++], cpu_group);
+               cpumask_andnot(tmp, tmp, cpu_group);
+       }
+
+       free_cpumask_var(tmp);
+       *pcpu_groups = cpu_groups;
+
+       return num_groups;
+}
+
+static int hotplug_tests(void)
+{
+       int i, nb_cpu_group, err = -ENOMEM;
+       cpumask_var_t offlined_cpus, *cpu_groups;
+       char *page_buf;
+
+       if (!alloc_cpumask_var(&offlined_cpus, GFP_KERNEL))
+               return err;
+
+       nb_cpu_group = alloc_init_cpu_groups(&cpu_groups);
+       if (nb_cpu_group < 0)
+               goto out_free_cpus;
+       page_buf = (char *)__get_free_page(GFP_KERNEL);
+       if (!page_buf)
+               goto out_free_cpu_groups;
+
+       err = 0;
+       /*
+        * Of course the last CPU cannot be powered down and cpu_down() should
+        * refuse doing that.
+        */
+       pr_info("Trying to turn off and on again all CPUs\n");
+       err += down_and_up_cpus(cpu_online_mask, offlined_cpus);
+
+       /*
+        * Take down CPUs by cpu group this time. When the last CPU is turned
+        * off, the cpu group itself should shut down.
+        */
+       for (i = 0; i < nb_cpu_group; ++i) {
+               ssize_t len = cpumap_print_to_pagebuf(true, page_buf,
+                                                     cpu_groups[i]);
+               /* Remove trailing newline. */
+               page_buf[len - 1] = '\0';
+               pr_info("Trying to turn off and on again group %d (CPUs %s)\n",
+                       i, page_buf);
+               err += down_and_up_cpus(cpu_groups[i], offlined_cpus);
+       }
+
+       free_page((unsigned long)page_buf);
+out_free_cpu_groups:
+       free_cpu_groups(nb_cpu_group, &cpu_groups);
+out_free_cpus:
+       free_cpumask_var(offlined_cpus);
+       return err;
+}
+
+static void dummy_callback(struct timer_list *unused) {}
+
+static int suspend_cpu(int index, bool broadcast)
+{
+       int ret;
+
+       arch_cpu_idle_enter();
+
+       if (broadcast) {
+               /*
+                * The local timer will be shut down, we need to enter tick
+                * broadcast.
+                */
+               ret = tick_broadcast_enter();
+               if (ret) {
+                       /*
+                        * In the absence of hardware broadcast mechanism,
+                        * this CPU might be used to broadcast wakeups, which
+                        * may be why entering tick broadcast has failed.
+                        * There is little the kernel can do to work around
+                        * that, so enter WFI instead (idle state 0).
+                        */
+                       cpu_do_idle();
+                       ret = 0;
+                       goto out_arch_exit;
+               }
+       }
+
+       /*
+        * Replicate the common ARM cpuidle enter function
+        * (arm_enter_idle_state).
+        */
+       ret = CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, index);
+
+       if (broadcast)
+               tick_broadcast_exit();
+
+out_arch_exit:
+       arch_cpu_idle_exit();
+
+       return ret;
+}
+
+static int suspend_test_thread(void *arg)
+{
+       int cpu = (long)arg;
+       int i, nb_suspend = 0, nb_shallow_sleep = 0, nb_err = 0;
+       struct sched_param sched_priority = { .sched_priority = MAX_RT_PRIO-1 };
+       struct cpuidle_device *dev;
+       struct cpuidle_driver *drv;
+       /* No need for an actual callback, we just want to wake up the CPU. */
+       struct timer_list wakeup_timer;
+
+       /* Wait for the main thread to give the start signal. */
+       wait_for_completion(&suspend_threads_started);
+
+       /* Set maximum priority to preempt all other threads on this CPU. */
+       if (sched_setscheduler_nocheck(current, SCHED_FIFO, &sched_priority))
+               pr_warn("Failed to set suspend thread scheduler on CPU %d\n",
+                       cpu);
+
+       dev = this_cpu_read(cpuidle_devices);
+       drv = cpuidle_get_cpu_driver(dev);
+
+       pr_info("CPU %d entering suspend cycles, states 1 through %d\n",
+               cpu, drv->state_count - 1);
+
+       timer_setup_on_stack(&wakeup_timer, dummy_callback, 0);
+       for (i = 0; i < NUM_SUSPEND_CYCLE; ++i) {
+               int index;
+               /*
+                * Test all possible states, except 0 (which is usually WFI and
+                * doesn't use PSCI).
+                */
+               for (index = 1; index < drv->state_count; ++index) {
+                       struct cpuidle_state *state = &drv->states[index];
+                       bool broadcast = state->flags & CPUIDLE_FLAG_TIMER_STOP;
+                       int ret;
+
+                       /*
+                        * Set the timer to wake this CPU up in some time (which
+                        * should be largely sufficient for entering suspend).
+                        * If the local tick is disabled when entering suspend,
+                        * suspend_cpu() takes care of switching to a broadcast
+                        * tick, so the timer will still wake us up.
+                        */
+                       mod_timer(&wakeup_timer, jiffies +
+                                 usecs_to_jiffies(state->target_residency));
+
+                       /* IRQs must be disabled during suspend operations. */
+                       local_irq_disable();
+
+                       ret = suspend_cpu(index, broadcast);
+
+                       /*
+                        * We have woken up. Re-enable IRQs to handle any
+                        * pending interrupt, do not wait until the end of the
+                        * loop.
+                        */
+                       local_irq_enable();
+
+                       if (ret == index) {
+                               ++nb_suspend;
+                       } else if (ret >= 0) {
+                               /* We did not enter the expected state. */
+                               ++nb_shallow_sleep;
+                       } else {
+                               pr_err("Failed to suspend CPU %d: error %d "
+                                      "(requested state %d, cycle %d)\n",
+                                      cpu, ret, index, i);
+                               ++nb_err;
+                       }
+               }
+       }
+
+       /*
+        * Disable the timer to make sure that the timer will not trigger
+        * later.
+        */
+       del_timer(&wakeup_timer);
+       destroy_timer_on_stack(&wakeup_timer);
+
+       if (atomic_dec_return_relaxed(&nb_active_threads) == 0)
+               complete(&suspend_threads_done);
+
+       /* Give up on RT scheduling and wait for termination. */
+       sched_priority.sched_priority = 0;
+       if (sched_setscheduler_nocheck(current, SCHED_NORMAL, &sched_priority))
+               pr_warn("Failed to set suspend thread scheduler on CPU %d\n",
+                       cpu);
+       for (;;) {
+               /* Needs to be set first to avoid missing a wakeup. */
+               set_current_state(TASK_INTERRUPTIBLE);
+               if (kthread_should_stop()) {
+                       __set_current_state(TASK_RUNNING);
+                       break;
+               }
+               schedule();
+       }
+
+       pr_info("CPU %d suspend test results: success %d, shallow states %d, errors %d\n",
+               cpu, nb_suspend, nb_shallow_sleep, nb_err);
+
+       return nb_err;
+}
+
+static int suspend_tests(void)
+{
+       int i, cpu, err = 0;
+       struct task_struct **threads;
+       int nb_threads = 0;
+
+       threads = kmalloc_array(nb_available_cpus, sizeof(*threads),
+                               GFP_KERNEL);
+       if (!threads)
+               return -ENOMEM;
+
+       /*
+        * Stop cpuidle to prevent the idle tasks from entering a deep sleep
+        * mode, as it might interfere with the suspend threads on other CPUs.
+        * This does not prevent the suspend threads from using cpuidle (only
+        * the idle tasks check this status). Take the idle lock so that
+        * the cpuidle driver and device look-up can be carried out safely.
+        */
+       cpuidle_pause_and_lock();
+
+       for_each_online_cpu(cpu) {
+               struct task_struct *thread;
+               /* Check that cpuidle is available on that CPU. */
+               struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
+               struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
+
+               if (!dev || !drv) {
+                       pr_warn("cpuidle not available on CPU %d, ignoring\n",
+                               cpu);
+                       continue;
+               }
+
+               thread = kthread_create_on_cpu(suspend_test_thread,
+                                              (void *)(long)cpu, cpu,
+                                              "psci_suspend_test");
+               if (IS_ERR(thread))
+                       pr_err("Failed to create kthread on CPU %d\n", cpu);
+               else
+                       threads[nb_threads++] = thread;
+       }
+
+       if (nb_threads < 1) {
+               err = -ENODEV;
+               goto out;
+       }
+
+       atomic_set(&nb_active_threads, nb_threads);
+
+       /*
+        * Wake up the suspend threads. To avoid the main thread being preempted
+        * before all the threads have been unparked, the suspend threads will
+        * wait for the completion of suspend_threads_started.
+        */
+       for (i = 0; i < nb_threads; ++i)
+               wake_up_process(threads[i]);
+       complete_all(&suspend_threads_started);
+
+       wait_for_completion(&suspend_threads_done);
+
+
+       /* Stop and destroy all threads, get return status. */
+       for (i = 0; i < nb_threads; ++i)
+               err += kthread_stop(threads[i]);
+ out:
+       cpuidle_resume_and_unlock();
+       kfree(threads);
+       return err;
+}
+
+static int __init psci_checker(void)
+{
+       int ret;
+
+       /*
+        * Since we're in an initcall, we assume that all the CPUs that all
+        * CPUs that can be onlined have been onlined.
+        *
+        * The tests assume that hotplug is enabled but nobody else is using it,
+        * otherwise the results will be unpredictable. However, since there
+        * is no userspace yet in initcalls, that should be fine, as long as
+        * no torture test is running at the same time (see Kconfig).
+        */
+       nb_available_cpus = num_online_cpus();
+
+       /* Check PSCI operations are set up and working. */
+       ret = psci_ops_check();
+       if (ret)
+               return ret;
+
+       pr_info("PSCI checker started using %u CPUs\n", nb_available_cpus);
+
+       pr_info("Starting hotplug tests\n");
+       ret = hotplug_tests();
+       if (ret == 0)
+               pr_info("Hotplug tests passed OK\n");
+       else if (ret > 0)
+               pr_err("%d error(s) encountered in hotplug tests\n", ret);
+       else {
+               pr_err("Out of memory\n");
+               return ret;
+       }
+
+       pr_info("Starting suspend tests (%d cycles per state)\n",
+               NUM_SUSPEND_CYCLE);
+       ret = suspend_tests();
+       if (ret == 0)
+               pr_info("Suspend tests passed OK\n");
+       else if (ret > 0)
+               pr_err("%d error(s) encountered in suspend tests\n", ret);
+       else {
+               switch (ret) {
+               case -ENOMEM:
+                       pr_err("Out of memory\n");
+                       break;
+               case -ENODEV:
+                       pr_warn("Could not start suspend tests on any CPU\n");
+                       break;
+               }
+       }
+
+       pr_info("PSCI checker completed\n");
+       return ret < 0 ? ret : 0;
+}
+late_initcall(psci_checker);
diff --git a/drivers/firmware/psci_checker.c b/drivers/firmware/psci_checker.c
deleted file mode 100644 (file)
index 3469436..0000000
+++ /dev/null
@@ -1,505 +0,0 @@
-/*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * Copyright (C) 2016 ARM Limited
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/atomic.h>
-#include <linux/completion.h>
-#include <linux/cpu.h>
-#include <linux/cpuidle.h>
-#include <linux/cpu_pm.h>
-#include <linux/kernel.h>
-#include <linux/kthread.h>
-#include <uapi/linux/sched/types.h>
-#include <linux/module.h>
-#include <linux/preempt.h>
-#include <linux/psci.h>
-#include <linux/slab.h>
-#include <linux/tick.h>
-#include <linux/topology.h>
-
-#include <asm/cpuidle.h>
-
-#include <uapi/linux/psci.h>
-
-#define NUM_SUSPEND_CYCLE (10)
-
-static unsigned int nb_available_cpus;
-static int tos_resident_cpu = -1;
-
-static atomic_t nb_active_threads;
-static struct completion suspend_threads_started =
-       COMPLETION_INITIALIZER(suspend_threads_started);
-static struct completion suspend_threads_done =
-       COMPLETION_INITIALIZER(suspend_threads_done);
-
-/*
- * We assume that PSCI operations are used if they are available. This is not
- * necessarily true on arm64, since the decision is based on the
- * "enable-method" property of each CPU in the DT, but given that there is no
- * arch-specific way to check this, we assume that the DT is sensible.
- */
-static int psci_ops_check(void)
-{
-       int migrate_type = -1;
-       int cpu;
-
-       if (!(psci_ops.cpu_off && psci_ops.cpu_on && psci_ops.cpu_suspend)) {
-               pr_warn("Missing PSCI operations, aborting tests\n");
-               return -EOPNOTSUPP;
-       }
-
-       if (psci_ops.migrate_info_type)
-               migrate_type = psci_ops.migrate_info_type();
-
-       if (migrate_type == PSCI_0_2_TOS_UP_MIGRATE ||
-           migrate_type == PSCI_0_2_TOS_UP_NO_MIGRATE) {
-               /* There is a UP Trusted OS, find on which core it resides. */
-               for_each_online_cpu(cpu)
-                       if (psci_tos_resident_on(cpu)) {
-                               tos_resident_cpu = cpu;
-                               break;
-                       }
-               if (tos_resident_cpu == -1)
-                       pr_warn("UP Trusted OS resides on no online CPU\n");
-       }
-
-       return 0;
-}
-
-/*
- * offlined_cpus is a temporary array but passing it as an argument avoids
- * multiple allocations.
- */
-static unsigned int down_and_up_cpus(const struct cpumask *cpus,
-                                    struct cpumask *offlined_cpus)
-{
-       int cpu;
-       int err = 0;
-
-       cpumask_clear(offlined_cpus);
-
-       /* Try to power down all CPUs in the mask. */
-       for_each_cpu(cpu, cpus) {
-               int ret = cpu_down(cpu);
-
-               /*
-                * cpu_down() checks the number of online CPUs before the TOS
-                * resident CPU.
-                */
-               if (cpumask_weight(offlined_cpus) + 1 == nb_available_cpus) {
-                       if (ret != -EBUSY) {
-                               pr_err("Unexpected return code %d while trying "
-                                      "to power down last online CPU %d\n",
-                                      ret, cpu);
-                               ++err;
-                       }
-               } else if (cpu == tos_resident_cpu) {
-                       if (ret != -EPERM) {
-                               pr_err("Unexpected return code %d while trying "
-                                      "to power down TOS resident CPU %d\n",
-                                      ret, cpu);
-                               ++err;
-                       }
-               } else if (ret != 0) {
-                       pr_err("Error occurred (%d) while trying "
-                              "to power down CPU %d\n", ret, cpu);
-                       ++err;
-               }
-
-               if (ret == 0)
-                       cpumask_set_cpu(cpu, offlined_cpus);
-       }
-
-       /* Try to power up all the CPUs that have been offlined. */
-       for_each_cpu(cpu, offlined_cpus) {
-               int ret = cpu_up(cpu);
-
-               if (ret != 0) {
-                       pr_err("Error occurred (%d) while trying "
-                              "to power up CPU %d\n", ret, cpu);
-                       ++err;
-               } else {
-                       cpumask_clear_cpu(cpu, offlined_cpus);
-               }
-       }
-
-       /*
-        * Something went bad at some point and some CPUs could not be turned
-        * back on.
-        */
-       WARN_ON(!cpumask_empty(offlined_cpus) ||
-               num_online_cpus() != nb_available_cpus);
-
-       return err;
-}
-
-static void free_cpu_groups(int num, cpumask_var_t **pcpu_groups)
-{
-       int i;
-       cpumask_var_t *cpu_groups = *pcpu_groups;
-
-       for (i = 0; i < num; ++i)
-               free_cpumask_var(cpu_groups[i]);
-       kfree(cpu_groups);
-}
-
-static int alloc_init_cpu_groups(cpumask_var_t **pcpu_groups)
-{
-       int num_groups = 0;
-       cpumask_var_t tmp, *cpu_groups;
-
-       if (!alloc_cpumask_var(&tmp, GFP_KERNEL))
-               return -ENOMEM;
-
-       cpu_groups = kcalloc(nb_available_cpus, sizeof(cpu_groups),
-                            GFP_KERNEL);
-       if (!cpu_groups)
-               return -ENOMEM;
-
-       cpumask_copy(tmp, cpu_online_mask);
-
-       while (!cpumask_empty(tmp)) {
-               const struct cpumask *cpu_group =
-                       topology_core_cpumask(cpumask_any(tmp));
-
-               if (!alloc_cpumask_var(&cpu_groups[num_groups], GFP_KERNEL)) {
-                       free_cpu_groups(num_groups, &cpu_groups);
-                       return -ENOMEM;
-               }
-               cpumask_copy(cpu_groups[num_groups++], cpu_group);
-               cpumask_andnot(tmp, tmp, cpu_group);
-       }
-
-       free_cpumask_var(tmp);
-       *pcpu_groups = cpu_groups;
-
-       return num_groups;
-}
-
-static int hotplug_tests(void)
-{
-       int i, nb_cpu_group, err = -ENOMEM;
-       cpumask_var_t offlined_cpus, *cpu_groups;
-       char *page_buf;
-
-       if (!alloc_cpumask_var(&offlined_cpus, GFP_KERNEL))
-               return err;
-
-       nb_cpu_group = alloc_init_cpu_groups(&cpu_groups);
-       if (nb_cpu_group < 0)
-               goto out_free_cpus;
-       page_buf = (char *)__get_free_page(GFP_KERNEL);
-       if (!page_buf)
-               goto out_free_cpu_groups;
-
-       err = 0;
-       /*
-        * Of course the last CPU cannot be powered down and cpu_down() should
-        * refuse doing that.
-        */
-       pr_info("Trying to turn off and on again all CPUs\n");
-       err += down_and_up_cpus(cpu_online_mask, offlined_cpus);
-
-       /*
-        * Take down CPUs by cpu group this time. When the last CPU is turned
-        * off, the cpu group itself should shut down.
-        */
-       for (i = 0; i < nb_cpu_group; ++i) {
-               ssize_t len = cpumap_print_to_pagebuf(true, page_buf,
-                                                     cpu_groups[i]);
-               /* Remove trailing newline. */
-               page_buf[len - 1] = '\0';
-               pr_info("Trying to turn off and on again group %d (CPUs %s)\n",
-                       i, page_buf);
-               err += down_and_up_cpus(cpu_groups[i], offlined_cpus);
-       }
-
-       free_page((unsigned long)page_buf);
-out_free_cpu_groups:
-       free_cpu_groups(nb_cpu_group, &cpu_groups);
-out_free_cpus:
-       free_cpumask_var(offlined_cpus);
-       return err;
-}
-
-static void dummy_callback(struct timer_list *unused) {}
-
-static int suspend_cpu(int index, bool broadcast)
-{
-       int ret;
-
-       arch_cpu_idle_enter();
-
-       if (broadcast) {
-               /*
-                * The local timer will be shut down, we need to enter tick
-                * broadcast.
-                */
-               ret = tick_broadcast_enter();
-               if (ret) {
-                       /*
-                        * In the absence of hardware broadcast mechanism,
-                        * this CPU might be used to broadcast wakeups, which
-                        * may be why entering tick broadcast has failed.
-                        * There is little the kernel can do to work around
-                        * that, so enter WFI instead (idle state 0).
-                        */
-                       cpu_do_idle();
-                       ret = 0;
-                       goto out_arch_exit;
-               }
-       }
-
-       /*
-        * Replicate the common ARM cpuidle enter function
-        * (arm_enter_idle_state).
-        */
-       ret = CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, index);
-
-       if (broadcast)
-               tick_broadcast_exit();
-
-out_arch_exit:
-       arch_cpu_idle_exit();
-
-       return ret;
-}
-
-static int suspend_test_thread(void *arg)
-{
-       int cpu = (long)arg;
-       int i, nb_suspend = 0, nb_shallow_sleep = 0, nb_err = 0;
-       struct sched_param sched_priority = { .sched_priority = MAX_RT_PRIO-1 };
-       struct cpuidle_device *dev;
-       struct cpuidle_driver *drv;
-       /* No need for an actual callback, we just want to wake up the CPU. */
-       struct timer_list wakeup_timer;
-
-       /* Wait for the main thread to give the start signal. */
-       wait_for_completion(&suspend_threads_started);
-
-       /* Set maximum priority to preempt all other threads on this CPU. */
-       if (sched_setscheduler_nocheck(current, SCHED_FIFO, &sched_priority))
-               pr_warn("Failed to set suspend thread scheduler on CPU %d\n",
-                       cpu);
-
-       dev = this_cpu_read(cpuidle_devices);
-       drv = cpuidle_get_cpu_driver(dev);
-
-       pr_info("CPU %d entering suspend cycles, states 1 through %d\n",
-               cpu, drv->state_count - 1);
-
-       timer_setup_on_stack(&wakeup_timer, dummy_callback, 0);
-       for (i = 0; i < NUM_SUSPEND_CYCLE; ++i) {
-               int index;
-               /*
-                * Test all possible states, except 0 (which is usually WFI and
-                * doesn't use PSCI).
-                */
-               for (index = 1; index < drv->state_count; ++index) {
-                       struct cpuidle_state *state = &drv->states[index];
-                       bool broadcast = state->flags & CPUIDLE_FLAG_TIMER_STOP;
-                       int ret;
-
-                       /*
-                        * Set the timer to wake this CPU up in some time (which
-                        * should be largely sufficient for entering suspend).
-                        * If the local tick is disabled when entering suspend,
-                        * suspend_cpu() takes care of switching to a broadcast
-                        * tick, so the timer will still wake us up.
-                        */
-                       mod_timer(&wakeup_timer, jiffies +
-                                 usecs_to_jiffies(state->target_residency));
-
-                       /* IRQs must be disabled during suspend operations. */
-                       local_irq_disable();
-
-                       ret = suspend_cpu(index, broadcast);
-
-                       /*
-                        * We have woken up. Re-enable IRQs to handle any
-                        * pending interrupt, do not wait until the end of the
-                        * loop.
-                        */
-                       local_irq_enable();
-
-                       if (ret == index) {
-                               ++nb_suspend;
-                       } else if (ret >= 0) {
-                               /* We did not enter the expected state. */
-                               ++nb_shallow_sleep;
-                       } else {
-                               pr_err("Failed to suspend CPU %d: error %d "
-                                      "(requested state %d, cycle %d)\n",
-                                      cpu, ret, index, i);
-                               ++nb_err;
-                       }
-               }
-       }
-
-       /*
-        * Disable the timer to make sure that the timer will not trigger
-        * later.
-        */
-       del_timer(&wakeup_timer);
-       destroy_timer_on_stack(&wakeup_timer);
-
-       if (atomic_dec_return_relaxed(&nb_active_threads) == 0)
-               complete(&suspend_threads_done);
-
-       /* Give up on RT scheduling and wait for termination. */
-       sched_priority.sched_priority = 0;
-       if (sched_setscheduler_nocheck(current, SCHED_NORMAL, &sched_priority))
-               pr_warn("Failed to set suspend thread scheduler on CPU %d\n",
-                       cpu);
-       for (;;) {
-               /* Needs to be set first to avoid missing a wakeup. */
-               set_current_state(TASK_INTERRUPTIBLE);
-               if (kthread_should_stop()) {
-                       __set_current_state(TASK_RUNNING);
-                       break;
-               }
-               schedule();
-       }
-
-       pr_info("CPU %d suspend test results: success %d, shallow states %d, errors %d\n",
-               cpu, nb_suspend, nb_shallow_sleep, nb_err);
-
-       return nb_err;
-}
-
-static int suspend_tests(void)
-{
-       int i, cpu, err = 0;
-       struct task_struct **threads;
-       int nb_threads = 0;
-
-       threads = kmalloc_array(nb_available_cpus, sizeof(*threads),
-                               GFP_KERNEL);
-       if (!threads)
-               return -ENOMEM;
-
-       /*
-        * Stop cpuidle to prevent the idle tasks from entering a deep sleep
-        * mode, as it might interfere with the suspend threads on other CPUs.
-        * This does not prevent the suspend threads from using cpuidle (only
-        * the idle tasks check this status). Take the idle lock so that
-        * the cpuidle driver and device look-up can be carried out safely.
-        */
-       cpuidle_pause_and_lock();
-
-       for_each_online_cpu(cpu) {
-               struct task_struct *thread;
-               /* Check that cpuidle is available on that CPU. */
-               struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
-               struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
-
-               if (!dev || !drv) {
-                       pr_warn("cpuidle not available on CPU %d, ignoring\n",
-                               cpu);
-                       continue;
-               }
-
-               thread = kthread_create_on_cpu(suspend_test_thread,
-                                              (void *)(long)cpu, cpu,
-                                              "psci_suspend_test");
-               if (IS_ERR(thread))
-                       pr_err("Failed to create kthread on CPU %d\n", cpu);
-               else
-                       threads[nb_threads++] = thread;
-       }
-
-       if (nb_threads < 1) {
-               err = -ENODEV;
-               goto out;
-       }
-
-       atomic_set(&nb_active_threads, nb_threads);
-
-       /*
-        * Wake up the suspend threads. To avoid the main thread being preempted
-        * before all the threads have been unparked, the suspend threads will
-        * wait for the completion of suspend_threads_started.
-        */
-       for (i = 0; i < nb_threads; ++i)
-               wake_up_process(threads[i]);
-       complete_all(&suspend_threads_started);
-
-       wait_for_completion(&suspend_threads_done);
-
-
-       /* Stop and destroy all threads, get return status. */
-       for (i = 0; i < nb_threads; ++i)
-               err += kthread_stop(threads[i]);
- out:
-       cpuidle_resume_and_unlock();
-       kfree(threads);
-       return err;
-}
-
-static int __init psci_checker(void)
-{
-       int ret;
-
-       /*
-        * Since we're in an initcall, we assume that all the CPUs that all
-        * CPUs that can be onlined have been onlined.
-        *
-        * The tests assume that hotplug is enabled but nobody else is using it,
-        * otherwise the results will be unpredictable. However, since there
-        * is no userspace yet in initcalls, that should be fine, as long as
-        * no torture test is running at the same time (see Kconfig).
-        */
-       nb_available_cpus = num_online_cpus();
-
-       /* Check PSCI operations are set up and working. */
-       ret = psci_ops_check();
-       if (ret)
-               return ret;
-
-       pr_info("PSCI checker started using %u CPUs\n", nb_available_cpus);
-
-       pr_info("Starting hotplug tests\n");
-       ret = hotplug_tests();
-       if (ret == 0)
-               pr_info("Hotplug tests passed OK\n");
-       else if (ret > 0)
-               pr_err("%d error(s) encountered in hotplug tests\n", ret);
-       else {
-               pr_err("Out of memory\n");
-               return ret;
-       }
-
-       pr_info("Starting suspend tests (%d cycles per state)\n",
-               NUM_SUSPEND_CYCLE);
-       ret = suspend_tests();
-       if (ret == 0)
-               pr_info("Suspend tests passed OK\n");
-       else if (ret > 0)
-               pr_err("%d error(s) encountered in suspend tests\n", ret);
-       else {
-               switch (ret) {
-               case -ENOMEM:
-                       pr_err("Out of memory\n");
-                       break;
-               case -ENODEV:
-                       pr_warn("Could not start suspend tests on any CPU\n");
-                       break;
-               }
-       }
-
-       pr_info("PSCI checker completed\n");
-       return ret < 0 ? ret : 0;
-}
-late_initcall(psci_checker);