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SubjectRe: [PATCH 4/6] ARM: psci: cpuidle: Introduce PSCI CPUidle driver
[...]

> +++ b/drivers/cpuidle/cpuidle-psci.c
> @@ -0,0 +1,150 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * PSCI CPU idle driver.
> + *
> + * Copyright (C) 2019 ARM Ltd.
> + * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> + */
> +
> +#define pr_fmt(fmt) "CPUidle PSCI: " fmt
> +
> +#include <linux/cpuidle.h>
> +#include <linux/cpumask.h>
> +#include <linux/cpu_pm.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/psci.h>
> +#include <linux/slab.h>
> +
> +#include <asm/cpuidle.h>

This should go away, right?

> +
> +#include "dt_idle_states.h"
> +
> +static int psci_enter_idle_state(struct cpuidle_device *dev,
> + struct cpuidle_driver *drv, int idx)
> +{
> + return CPU_PM_CPU_IDLE_ENTER(psci_cpu_suspend_enter, idx);
> +}
> +
> +static struct cpuidle_driver psci_idle_driver __initdata = {
> + .name = "psci_idle",
> + .owner = THIS_MODULE,
> + /*
> + * PSCI idle states relies on architectural WFI to
> + * be represented as state index 0.
> + */
> + .states[0] = {
> + .enter = psci_enter_idle_state,
> + .exit_latency = 1,
> + .target_residency = 1,
> + .power_usage = UINT_MAX,
> + .name = "WFI",
> + .desc = "ARM WFI",
> + }
> +};
> +
> +static const struct of_device_id psci_idle_state_match[] __initconst = {
> + { .compatible = "arm,idle-state",
> + .data = psci_enter_idle_state },
> + { },
> +};
> +
> +static int __init psci_idle_init_cpu(int cpu)
> +{
> + struct cpuidle_driver *drv;
> + struct device_node *cpu_node;
> + const char *enable_method;
> + int ret = 0;
> +
> + drv = kmemdup(&psci_idle_driver, sizeof(*drv), GFP_KERNEL);
> + if (!drv)
> + return -ENOMEM;
> +
> + drv->cpumask = (struct cpumask *)cpumask_of(cpu);
> +
> + cpu_node = of_get_cpu_node(cpu, NULL);
> + if (!cpu_node)
> + return -ENODEV;

You should free drv in case of error here (goto out_kfree_drv; etc).

> +
> + /*
> + * Check whether the enable-method for the cpu is PSCI, fail
> + * if it is not.
> + */
> + enable_method = of_get_property(cpu_node, "enable-method", NULL);
> + if (!enable_method || (strcmp(enable_method, "psci")))
> + ret = -ENODEV;
> +
> + of_node_put(cpu_node);
> + if (ret)
> + return ret;

You should free drv in case of error here (goto out_kfree_drv;).

> +
> + /*
> + * Initialize idle states data, starting at index 1, since
> + * by default idle state 0 is the quiescent state reached
> + * by the cpu by executing the wfi instruction.
> + *
> + * If no DT idle states are detected (ret == 0) let the driver
> + * initialization fail accordingly since there is no reason to
> + * initialize the idle driver if only wfi is supported, the
> + * default archictectural back-end already executes wfi
> + * on idle entry.
> + */
> + ret = dt_init_idle_driver(drv, psci_idle_state_match, 1);
> + if (ret <= 0) {
> + ret = ret ? : -ENODEV;
> + goto out_kfree_drv;
> + }
> +
> + /*
> + * Initialize PSCI idle states.
> + */
> + ret = psci_cpu_init_idle(cpu);
> + if (ret) {
> + pr_err("CPU %d failed to PSCI idle\n", cpu);
> + goto out_kfree_drv;
> + }
> +
> + ret = cpuidle_register(drv, NULL);
> + if (ret)
> + goto out_kfree_drv;
> +
> + return 0;
> +
> +out_kfree_drv:
> + kfree(drv);
> + return ret;
> +}
> +

[...]

Kind regards
Uffe

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