LXR linux/arch/arm/plat-mxc/iram

   1/*
   2 * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License
   6 * as published by the Free Software Foundation; either version 2
   7 * of the License, or (at your option) any later version.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the Free Software
  16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  17 * MA 02110-1301, USA.
  18 */
  19
  20#include <linux/kernel.h>
  21#include <linux/io.h>
  22#include <linux/module.h>
  23#include <linux/spinlock.h>
  24#include <linux/genalloc.h>
  25#include <mach/iram.h>
  26
  27static unsigned long iram_phys_base;
  28static void __iomem *iram_virt_base;
  29static struct gen_pool *iram_pool;
  30
  31static inline void __iomem *iram_phys_to_virt(unsigned long p)
  32{
  33        return iram_virt_base + (p - iram_phys_base);
  34}
  35
  36void __iomem *iram_alloc(unsigned int size, unsigned long *dma_addr)
  37{
  38        if (!iram_pool)
  39                return NULL;
  40
  41        *dma_addr = gen_pool_alloc(iram_pool, size);
  42        pr_debug("iram alloc - %dB@0x%lX\n", size, *dma_addr);
  43        if (!*dma_addr)
  44                return NULL;
  45        return iram_phys_to_virt(*dma_addr);
  46}
  47EXPORT_SYMBOL(iram_alloc);
  48
  49void iram_free(unsigned long addr, unsigned int size)
  50{
  51        if (!iram_pool)
  52                return;
  53
  54        gen_pool_free(iram_pool, addr, size);
  55}
  56EXPORT_SYMBOL(iram_free);
  57
  58int __init iram_init(unsigned long base, unsigned long size)
  59{
  60        iram_phys_base = base;
  61
  62        iram_pool = gen_pool_create(PAGE_SHIFT, -1);
  63        if (!iram_pool)
  64                return -ENOMEM;
  65
  66        gen_pool_add(iram_pool, base, size, -1);
  67        iram_virt_base = ioremap(iram_phys_base, size);
  68        if (!iram_virt_base)
  69                return -EIO;
  70
  71        pr_debug("i.MX IRAM pool: %ld KB@0x%p\n", size / 1024, iram_virt_base);
  72        return 0;
  73}
  74