linux-imx

/*

 * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * 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.

 */

​

#include <linux/io.h>

#include <linux/log2.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/of_address.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

​

/* System Bus Controller registers */

#define UNIPHIER_SBC_BASE   0x100   /* base address of bank0 space */

#define    UNIPHIER_SBC_BASE_BE     BIT(0)  /* bank_enable */

#define UNIPHIER_SBC_CTRL0  0x200   /* timing parameter 0 of bank0 */

#define UNIPHIER_SBC_CTRL1  0x204   /* timing parameter 1 of bank0 */

#define UNIPHIER_SBC_CTRL2  0x208   /* timing parameter 2 of bank0 */

#define UNIPHIER_SBC_CTRL3  0x20c   /* timing parameter 3 of bank0 */

#define UNIPHIER_SBC_CTRL4  0x300   /* timing parameter 4 of bank0 */

​

#define UNIPHIER_SBC_STRIDE 0x10    /* register stride to next bank */

#define UNIPHIER_SBC_NR_BANKS   8   /* number of banks (chip select) */

#define UNIPHIER_SBC_BASE_DUMMY 0xffffffff  /* data to squash bank 0, 1 */

​

struct uniphier_system_bus_bank {

    u32 base;

    u32 end;

};

​

struct uniphier_system_bus_priv {

    struct device *dev;

    void __iomem *membase;

    struct uniphier_system_bus_bank bank[UNIPHIER_SBC_NR_BANKS];

};

​

static int uniphier_system_bus_add_bank(struct uniphier_system_bus_priv *priv,

                    int bank, u32 addr, u64 paddr, u32 size)

{

    u64 end, mask;

​

    dev_dbg(priv->dev,

        "range found: bank = %d, addr = %08x, paddr = %08llx, size = %08x\n",

        bank, addr, paddr, size);

​

    if (bank >= ARRAY_SIZE(priv->bank)) {

        dev_err(priv->dev, "unsupported bank number %d\n", bank);

        return -EINVAL;

    }

​

    if (priv->bank[bank].base || priv->bank[bank].end) {

        dev_err(priv->dev,

            "range for bank %d has already been specified\n", bank);

        return -EINVAL;

    }

​

    if (paddr > U32_MAX) {

        dev_err(priv->dev, "base address %llx is too high\n", paddr);

        return -EINVAL;

    }

​

    end = paddr + size;

​

    if (addr > paddr) {

        dev_err(priv->dev,

            "base %08x cannot be mapped to %08llx of parent\n",

            addr, paddr);

        return -EINVAL;

    }

    paddr -= addr;

​

    paddr = round_down(paddr, 0x00020000);

    end = round_up(end, 0x00020000);

​

    if (end > U32_MAX) {

        dev_err(priv->dev, "end address %08llx is too high\n", end);

        return -EINVAL;

    }

    mask = paddr ^ (end - 1);

    mask = roundup_pow_of_two(mask);

​

    paddr = round_down(paddr, mask);