linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 * Allwinner sunXi SoCs Security ID support.

 *

 * Copyright (c) 2013 Oliver Schinagl <oliver@schinagl.nl>

 * Copyright (C) 2014 Maxime Ripard <maxime.ripard@free-electrons.com>

 */

​

#include <linux/device.h>

#include <linux/io.h>

#include <linux/iopoll.h>

#include <linux/module.h>

#include <linux/nvmem-provider.h>

#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/slab.h>

#include <linux/random.h>

​

/* Registers and special values for doing register-based SID readout on H3 */

#define SUN8I_SID_PRCTL     0x40

#define SUN8I_SID_RDKEY     0x60

​

#define SUN8I_SID_OFFSET_MASK   0x1FF

#define SUN8I_SID_OFFSET_SHIFT  16

#define SUN8I_SID_OP_LOCK   (0xAC << 8)

#define SUN8I_SID_READ      BIT(1)

​

struct sunxi_sid_cfg {

    u32 value_offset;

    u32 size;

    bool    need_register_readout;

};

​

struct sunxi_sid {

    void __iomem        *base;

    u32         value_offset;

};

​

static int sunxi_sid_read(void *context, unsigned int offset,

              void *val, size_t bytes)

{

    struct sunxi_sid *sid = context;

​

    memcpy_fromio(val, sid->base + sid->value_offset + offset, bytes);

​

    return 0;

}

​

static int sun8i_sid_register_readout(const struct sunxi_sid *sid,

                      const unsigned int offset,

                      u32 *out)

{

    u32 reg_val;

    int ret;

​

    /* Set word, lock access, and set read command */

    reg_val = (offset & SUN8I_SID_OFFSET_MASK)

          << SUN8I_SID_OFFSET_SHIFT;

    reg_val |= SUN8I_SID_OP_LOCK | SUN8I_SID_READ;

    writel(reg_val, sid->base + SUN8I_SID_PRCTL);

​

    ret = readl_poll_timeout(sid->base + SUN8I_SID_PRCTL, reg_val,