linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * SIRF hardware spinlock driver

 *

 * Copyright (c) 2015 Cambridge Silicon Radio Limited, a CSR plc group company.

 */

​

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/device.h>

#include <linux/io.h>

#include <linux/pm_runtime.h>

#include <linux/slab.h>

#include <linux/spinlock.h>

#include <linux/hwspinlock.h>

#include <linux/platform_device.h>

#include <linux/of.h>

#include <linux/of_address.h>

​

#include "hwspinlock_internal.h"

​

struct sirf_hwspinlock {

    void __iomem *io_base;

    struct hwspinlock_device bank;

};

​

/* Number of Hardware Spinlocks*/

#define HW_SPINLOCK_NUMBER  30

​

/* Hardware spinlock register offsets */

#define HW_SPINLOCK_BASE    0x404

#define HW_SPINLOCK_OFFSET(x)   (HW_SPINLOCK_BASE + 0x4 * (x))

​

static int sirf_hwspinlock_trylock(struct hwspinlock *lock)

{

    void __iomem *lock_addr = lock->priv;

​

    /* attempt to acquire the lock by reading value == 1 from it */

    return !!readl(lock_addr);

}

​

static void sirf_hwspinlock_unlock(struct hwspinlock *lock)

{

    void __iomem *lock_addr = lock->priv;

​

    /* release the lock by writing 0 to it */

    writel(0, lock_addr);

}

​

static const struct hwspinlock_ops sirf_hwspinlock_ops = {

    .trylock = sirf_hwspinlock_trylock,

    .unlock = sirf_hwspinlock_unlock,

};

​

static int sirf_hwspinlock_probe(struct platform_device *pdev)

{

    struct sirf_hwspinlock *hwspin;

    struct hwspinlock *hwlock;

    int idx, ret;

​

    if (!pdev->dev.of_node)

        return -ENODEV;

​