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
27 static unsigned long iram_phys_base;
28 static void __iomem *iram_virt_base;
29 static struct gen_pool *iram_pool;
30
iram_phys_to_virt(unsigned long p)31 static inline void __iomem *iram_phys_to_virt(unsigned long p)
32 {
33 return iram_virt_base + (p - iram_phys_base);
34 }
35
iram_alloc(unsigned int size,unsigned long * dma_addr)36 void __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 }
47 EXPORT_SYMBOL(iram_alloc);
48
iram_free(unsigned long addr,unsigned int size)49 void 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 }
56 EXPORT_SYMBOL(iram_free);
57
iram_init(unsigned long base,unsigned long size)58 int __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