linux-imx

/*

 * TI AM33XX SRAM EMIF Driver

 *

 * Copyright (C) 2016-2017 Texas Instruments Inc.

 *  Dave Gerlach

 *

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

 * modify it under the terms of the GNU General Public License

 * version 2 as published by the Free Software Foundation.

 *

 * 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/err.h>

#include <linux/genalloc.h>

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

#include <linux/sram.h>

#include <linux/ti-emif-sram.h>

​

#include "emif.h"

​

#define TI_EMIF_SRAM_SYMBOL_OFFSET(sym) ((unsigned long)(sym) - \

                     (unsigned long)&ti_emif_sram)

​

#define EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES       0x00a0

​

struct ti_emif_data {

    phys_addr_t ti_emif_sram_phys;

    phys_addr_t ti_emif_sram_data_phys;

    unsigned long ti_emif_sram_virt;

    unsigned long ti_emif_sram_data_virt;

    struct gen_pool *sram_pool_code;

    struct gen_pool *sram_pool_data;

    struct ti_emif_pm_data pm_data;

    struct ti_emif_pm_functions pm_functions;

};

​

static struct ti_emif_data *emif_instance;

​

static u32 sram_suspend_address(struct ti_emif_data *emif_data,

                unsigned long addr)

{

    return (emif_data->ti_emif_sram_virt +

        TI_EMIF_SRAM_SYMBOL_OFFSET(addr));

}

​

static phys_addr_t sram_resume_address(struct ti_emif_data *emif_data,

                       unsigned long addr)

{

    return ((unsigned long)emif_data->ti_emif_sram_phys +

        TI_EMIF_SRAM_SYMBOL_OFFSET(addr));

}

​

static void ti_emif_free_sram(struct ti_emif_data *emif_data)

{

    gen_pool_free(emif_data->sram_pool_code, emif_data->ti_emif_sram_virt,

              ti_emif_sram_sz);

    gen_pool_free(emif_data->sram_pool_data,

              emif_data->ti_emif_sram_data_virt,

              sizeof(struct emif_regs_amx3));

}

​

static int ti_emif_alloc_sram(struct device *dev,

                  struct ti_emif_data *emif_data)

{

    struct device_node *np = dev->of_node;

    int ret;

​

    emif_data->sram_pool_code = of_gen_pool_get(np, "sram", 0);

    if (!emif_data->sram_pool_code) {

        dev_err(dev, "Unable to get sram pool for ocmcram code\n");

        return -ENODEV;

    }

​

    emif_data->ti_emif_sram_virt =

            gen_pool_alloc(emif_data->sram_pool_code,

                       ti_emif_sram_sz);

    if (!emif_data->ti_emif_sram_virt) {

        dev_err(dev, "Unable to allocate code memory from ocmcram\n");

        return -ENOMEM;

    }

​

    /* Save physical address to calculate resume offset during pm init */

    emif_data->ti_emif_sram_phys =