/*
* Simple memory allocator for on-board SRAM
*
*
* Maintainer : Sylvain Munaut <tnt@246tNt.com>
*
* Copyright (C) 2005 Sylvain Munaut <tnt@246tNt.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/of.h>
#include <asm/io.h>
#include <asm/mmu.h>
#include "sram.h"
/* Struct keeping our 'state' */
struct bcom_sram *bcom_sram = NULL;
EXPORT_SYMBOL_GPL(bcom_sram); /* needed for inline functions */
/* ======================================================================== */
/* Public API */
/* ======================================================================== */
/* DO NOT USE in interrupts, if needed in irq handler, we should use the
_irqsave version of the spin_locks */
int bcom_sram_init(struct device_node *sram_node, char *owner)
{
int rv;
const u32 *regaddr_p;
u64 regaddr64, size64;
unsigned int psize;
/* Create our state struct */
if (bcom_sram) {
printk(KERN_ERR "%s: bcom_sram_init: "
"Already initialized !\n", owner);
return -EBUSY;
}
bcom_sram = kmalloc(sizeof(struct bcom_sram), GFP_KERNEL);
if (!bcom_sram) {
printk(KERN_ERR "%s: bcom_sram_init: "
"Couldn't allocate internal state !\n", owner);
return -ENOMEM;
}
/* Get address and size of the sram */
regaddr_p = of_get_address(sram_node, 0, &size64, NULL);
if (!regaddr_p) {
printk(KERN_ERR "%s: bcom_sram_init: "
"Invalid device node !\n", owner);
rv = -EINVAL;
goto error_free;
}
regaddr64 = of_translate_address(sram_node, regaddr_p);
bcom_sram->base_phys = (phys_addr_t) regaddr64;
bcom_sram->size = (unsigned int) size64;
/* Request region */
if (!request_mem_region(bcom_sram->base_phys, bcom_sram->size, owner)) {
printk(KERN_ERR "%s: bcom_sram_init: "
"Couldn't request region !\n", owner);
rv = -EBUSY;
goto error_free;
}
/* Map SRAM */
/* sram is not really __iomem */
bcom_sram->base_virt = (void*) ioremap(bcom_sram->base_phys, bcom_sram->size);
if (!bcom_sram->base_virt) {
printk(KERN_ERR "%s: bcom_sram_init: "
"Map error SRAM zone 0x%08lx (0x%0x)!\n",
owner, (long)bcom_sram->base_phys, bcom_sram->size );
rv = -ENOMEM;
goto error_release;
}
/* Create an rheap (defaults to 32 bits word alignment) */
bcom_sram->rh = rh_create(4);
/* Attach the free zones */
#if 0
/* Currently disabled ... for future use only */
reg_addr_p = of_get_property(sram_node, "available", &psize);
#else
regaddr_p = NULL;
psize = 0;
#endif
if (!regaddr_p || !psize) {
/* Attach the whole zone */
rh_attach_region(bcom_sram->rh, 0, bcom_sram->size);
} else {
/* Attach each zone independently */
while (psize >= 2 * sizeof(u32)) {
phys_addr_t zbase = of_translate_address(sram_node, regaddr_p);
rh_attach_region(bcom_sram->rh, zbase - bcom_sram->base_phys, regaddr_p[1]);
regaddr_p += 2;
psize -= 2 * sizeof(u32);
}
}
/* Init our spinlock */
spin_lock_init(&bcom_sram->lock);
return 0;
error_release:
release_mem_region(bcom_sram->base_phys, bcom_sram->size);
error_free:
kfree(bcom_sram);
bcom_sram = NULL;
return rv;
}
EXPORT_SYMBOL_GPL(bcom_sram_init);
void bcom_sram_cleanup(void)
{
/* Free resources */
if (bcom_sram) {
rh_destroy(bcom_sram->rh);
iounmap((void __iomem *)bcom_sram->base_virt);
release_mem_region(bcom_sram->base_phys, bcom_sram->size);
kfree(bcom_sram);
bcom_sram = NULL;
}
}
EXPORT_SYMBOL_GPL(bcom_sram_cleanup);
void* bcom_sram_alloc(int size, int align, phys_addr_t *phys)
{
unsigned long offset;
spin_lock(&bcom_sram->lock);
offset = rh_alloc_align(bcom_sram->rh, size, align, NULL);
spin_unlock(&bcom_sram->lock);
if (IS_ERR_VALUE(offset))
return NULL;
*phys = bcom_sram->base_phys + offset;
return bcom_sram->base_virt + offset;
}
EXPORT_SYMBOL_GPL(bcom_sram_alloc);
void bcom_sram_free(void *ptr)
{
unsigned long offset;
if (!ptr)
return;
offset = ptr - bcom_sram->base_virt;
spin_lock(&bcom_sram->lock);
rh_free(bcom_sram->rh, offset);
spin_unlock(&bcom_sram->lock);
}
EXPORT_SYMBOL_GPL(bcom_sram_free);
