linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Driver for the Intel P-Unit Mailbox IPC mechanism

 *

 * (C) Copyright 2015 Intel Corporation

 *

 * The heart of the P-Unit is the Foxton microcontroller and its firmware,

 * which provide mailbox interface for power management usage.

 */

​

#include <linux/acpi.h>

#include <linux/bitops.h>

#include <linux/delay.h>

#include <linux/device.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/mod_devicetable.h>

#include <linux/module.h>

#include <linux/platform_device.h>

​

#include <asm/intel_punit_ipc.h>

​

/* IPC Mailbox registers */

#define OFFSET_DATA_LOW     0x0

#define OFFSET_DATA_HIGH    0x4

/* bit field of interface register */

#define CMD_RUN         BIT(31)

#define CMD_ERRCODE_MASK    GENMASK(7, 0)

#define CMD_PARA1_SHIFT     8

#define CMD_PARA2_SHIFT     16

​

#define CMD_TIMEOUT_SECONDS 1

​

enum {

    BASE_DATA = 0,

    BASE_IFACE,

    BASE_MAX,

};

​

typedef struct {

    struct device *dev;

    struct mutex lock;

    int irq;

    struct completion cmd_complete;

    /* base of interface and data registers */

    void __iomem *base[RESERVED_IPC][BASE_MAX];

    IPC_TYPE type;

} IPC_DEV;

​

static IPC_DEV *punit_ipcdev;

​

static inline u32 ipc_read_status(IPC_DEV *ipcdev, IPC_TYPE type)

{

    return readl(ipcdev->base[type][BASE_IFACE]);

}

​

static inline void ipc_write_cmd(IPC_DEV *ipcdev, IPC_TYPE type, u32 cmd)

{

    writel(cmd, ipcdev->base[type][BASE_IFACE]);

}

​

static inline u32 ipc_read_data_low(IPC_DEV *ipcdev, IPC_TYPE type)

{