sram.c
/*
* linux/arch/arm/mach-mmp/sram.c
*
* based on mach-davinci/sram.c - DaVinci simple SRAM allocator
*
* Copyright (c) 2011 Marvell Semiconductors Inc.
* All Rights Reserved
*
* Add for mmp sram support - Leo Yan <leoy@marvell.com>
*
* 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.
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/genalloc.h>
#include <linux/platform_data/dma-mmp_tdma.h>
struct sram_bank_info {
char *pool_name;
struct gen_pool *gpool;
int granularity;
phys_addr_t sram_phys;
void __iomem *sram_virt;
u32 sram_size;
struct list_head node;
};
static DEFINE_MUTEX(sram_lock);
static LIST_HEAD(sram_bank_list);
struct gen_pool *sram_get_gpool(char *pool_name)
{
struct sram_bank_info *info = NULL;
if (!pool_name)
return NULL;
mutex_lock(&sram_lock);
list_for_each_entry(info, &sram_bank_list, node)
if (!strcmp(pool_name, info->pool_name))
break;
mutex_unlock(&sram_lock);
if (&info->node == &sram_bank_list)
return NULL;
return info->gpool;
}
EXPORT_SYMBOL(sram_get_gpool);
static int sram_probe(struct platform_device *pdev)
{
struct sram_platdata *pdata = pdev->dev.platform_data;
struct sram_bank_info *info;
struct resource *res;
int ret = 0;
if (!pdata || !pdata->pool_name)
return -ENODEV;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "no memory resource defined\n");
ret = -ENODEV;
goto out;
}
if (!resource_size(res))
return 0;
info->sram_phys = (phys_addr_t)res->start;
info->sram_size = resource_size(res);
info->sram_virt = ioremap(info->sram_phys, info->sram_size);
info->pool_name = kstrdup(pdata->pool_name, GFP_KERNEL);
info->granularity = pdata->granularity;
info->gpool = gen_pool_create(ilog2(info->granularity), -1);
if (!info->gpool) {
dev_err(&pdev->dev, "create pool failed\n");
ret = -ENOMEM;
goto create_pool_err;
}
ret = gen_pool_add_virt(info->gpool, (unsigned long)info->sram_virt,
info->sram_phys, info->sram_size, -1);
if (ret < 0) {
dev_err(&pdev->dev, "add new chunk failed\n");
ret = -ENOMEM;
goto add_chunk_err;
}
mutex_lock(&sram_lock);
list_add(&info->node, &sram_bank_list);
mutex_unlock(&sram_lock);
platform_set_drvdata(pdev, info);
dev_info(&pdev->dev, "initialized\n");
return 0;
add_chunk_err:
gen_pool_destroy(info->gpool);
create_pool_err:
iounmap(info->sram_virt);
kfree(info->pool_name);
out:
kfree(info);
return ret;
}
static int sram_remove(struct platform_device *pdev)
{
struct sram_bank_info *info;
info = platform_get_drvdata(pdev);
if (info == NULL)
return -ENODEV;
mutex_lock(&sram_lock);
list_del(&info->node);
mutex_unlock(&sram_lock);
gen_pool_destroy(info->gpool);
iounmap(info->sram_virt);
kfree(info->pool_name);
kfree(info);
return 0;
}
static const struct platform_device_id sram_id_table[] = {
{ "asram", MMP_ASRAM },
{ "isram", MMP_ISRAM },
{ }
};
static struct platform_driver sram_driver = {
.probe = sram_probe,
.remove = sram_remove,
.driver = {
.name = "mmp-sram",
},
.id_table = sram_id_table,
};
static int __init sram_init(void)
{
return platform_driver_register(&sram_driver);
}
core_initcall(sram_init);
MODULE_LICENSE("GPL");