linux/arch/arm/plat-mxc/iram_alloc.c

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/*
* Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*/
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/genalloc.h>
#include <mach/iram.h>
static unsigned long iram_phys_base;
static void __iomem *iram_virt_base;
static struct gen_pool *iram_pool;
static inline void __iomem *iram_phys_to_virt(unsigned long p)
{
return iram_virt_base + (p - iram_phys_base);
}
void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr)
{
if (!iram_pool)
return NULL;
*dma_addr = gen_pool_alloc(iram_pool, size);
pr_debug("iram alloc - %dB@0x%lX\n", size, *dma_addr);
if (!*dma_addr)
return NULL;
return iram_phys_to_virt(*dma_addr);
}
EXPORT_SYMBOL(iram_alloc);
void iram_free(unsigned long addr, unsigned int size)
{
if (!iram_pool)
return;
gen_pool_free(iram_pool, addr, size);
}
EXPORT_SYMBOL(iram_free);
int __init iram_init(unsigned long base, unsigned long size)
{
iram_phys_base = base;
iram_pool = gen_pool_create(PAGE_SHIFT, -1);
if (!iram_pool)
return -ENOMEM;
gen_pool_add(iram_pool, base, size, -1);
iram_virt_base = ioremap(iram_phys_base, size);
if (!iram_virt_base)
return -EIO;
pr_debug("i.MX IRAM pool: %ld KB@0x%p\n", size / 1024, iram_virt_base);
return 0;
}