430 lines
10 KiB
C
430 lines
10 KiB
C
|
/*
|
||
|
|
* Generic on-chip SRAM allocation driver
|
||
|
|
*
|
||
|
|
* Copyright (C) 2012 Philipp Zabel, Pengutronix
|
||
|
|
*
|
||
|
|
* 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/clk.h>
|
||
|
|
#include <linux/genalloc.h>
|
||
|
|
#include <linux/io.h>
|
||
|
|
#include <linux/list_sort.h>
|
||
|
|
#include <linux/of_address.h>
|
||
|
|
#include <linux/platform_device.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
|
||
|
|
#define SRAM_GRANULARITY 32
|
||
|
|
|
||
|
|
struct sram_partition {
|
||
|
|
void __iomem *base;
|
||
|
|
|
||
|
|
struct gen_pool *pool;
|
||
|
|
struct bin_attribute battr;
|
||
|
|
struct mutex lock;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct sram_dev {
|
||
|
|
struct device *dev;
|
||
|
|
void __iomem *virt_base;
|
||
|
|
|
||
|
|
struct gen_pool *pool;
|
||
|
|
struct clk *clk;
|
||
|
|
|
||
|
|
struct sram_partition *partition;
|
||
|
|
u32 partitions;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct sram_reserve {
|
||
|
|
struct list_head list;
|
||
|
|
u32 start;
|
||
|
|
u32 size;
|
||
|
|
bool export;
|
||
|
|
bool pool;
|
||
|
|
const char *label;
|
||
|
|
};
|
||
|
|
|
||
|
|
static ssize_t sram_read(struct file *filp, struct kobject *kobj,
|
||
|
|
struct bin_attribute *attr,
|
||
|
|
char *buf, loff_t pos, size_t count)
|
||
|
|
{
|
||
|
|
struct sram_partition *part;
|
||
|
|
|
||
|
|
part = container_of(attr, struct sram_partition, battr);
|
||
|
|
|
||
|
|
mutex_lock(&part->lock);
|
||
|
|
memcpy_fromio(buf, part->base + pos, count);
|
||
|
|
mutex_unlock(&part->lock);
|
||
|
|
|
||
|
|
return count;
|
||
|
|
}
|
||
|
|
|
||
|
|
static ssize_t sram_write(struct file *filp, struct kobject *kobj,
|
||
|
|
struct bin_attribute *attr,
|
||
|
|
char *buf, loff_t pos, size_t count)
|
||
|
|
{
|
||
|
|
struct sram_partition *part;
|
||
|
|
|
||
|
|
part = container_of(attr, struct sram_partition, battr);
|
||
|
|
|
||
|
|
mutex_lock(&part->lock);
|
||
|
|
memcpy_toio(part->base + pos, buf, count);
|
||
|
|
mutex_unlock(&part->lock);
|
||
|
|
|
||
|
|
return count;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_add_pool(struct sram_dev *sram, struct sram_reserve *block,
|
||
|
|
phys_addr_t start, struct sram_partition *part)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
part->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY),
|
||
|
|
NUMA_NO_NODE, block->label);
|
||
|
|
if (IS_ERR(part->pool))
|
||
|
|
return PTR_ERR(part->pool);
|
||
|
|
|
||
|
|
ret = gen_pool_add_virt(part->pool, (unsigned long)part->base, start,
|
||
|
|
block->size, NUMA_NO_NODE);
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_err(sram->dev, "failed to register subpool: %d\n", ret);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_add_export(struct sram_dev *sram, struct sram_reserve *block,
|
||
|
|
phys_addr_t start, struct sram_partition *part)
|
||
|
|
{
|
||
|
|
sysfs_bin_attr_init(&part->battr);
|
||
|
|
part->battr.attr.name = devm_kasprintf(sram->dev, GFP_KERNEL,
|
||
|
|
"%llx.sram",
|
||
|
|
(unsigned long long)start);
|
||
|
|
if (!part->battr.attr.name)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
part->battr.attr.mode = S_IRUSR | S_IWUSR;
|
||
|
|
part->battr.read = sram_read;
|
||
|
|
part->battr.write = sram_write;
|
||
|
|
part->battr.size = block->size;
|
||
|
|
|
||
|
|
return device_create_bin_file(sram->dev, &part->battr);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_add_partition(struct sram_dev *sram, struct sram_reserve *block,
|
||
|
|
phys_addr_t start)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
struct sram_partition *part = &sram->partition[sram->partitions];
|
||
|
|
|
||
|
|
mutex_init(&part->lock);
|
||
|
|
part->base = sram->virt_base + block->start;
|
||
|
|
|
||
|
|
if (block->pool) {
|
||
|
|
ret = sram_add_pool(sram, block, start, part);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
if (block->export) {
|
||
|
|
ret = sram_add_export(sram, block, start, part);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
sram->partitions++;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void sram_free_partitions(struct sram_dev *sram)
|
||
|
|
{
|
||
|
|
struct sram_partition *part;
|
||
|
|
|
||
|
|
if (!sram->partitions)
|
||
|
|
return;
|
||
|
|
|
||
|
|
part = &sram->partition[sram->partitions - 1];
|
||
|
|
for (; sram->partitions; sram->partitions--, part--) {
|
||
|
|
if (part->battr.size)
|
||
|
|
device_remove_bin_file(sram->dev, &part->battr);
|
||
|
|
|
||
|
|
if (part->pool &&
|
||
|
|
gen_pool_avail(part->pool) < gen_pool_size(part->pool))
|
||
|
|
dev_err(sram->dev, "removed pool while SRAM allocated\n");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_reserve_cmp(void *priv, struct list_head *a,
|
||
|
|
struct list_head *b)
|
||
|
|
{
|
||
|
|
struct sram_reserve *ra = list_entry(a, struct sram_reserve, list);
|
||
|
|
struct sram_reserve *rb = list_entry(b, struct sram_reserve, list);
|
||
|
|
|
||
|
|
return ra->start - rb->start;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
|
||
|
|
{
|
||
|
|
struct device_node *np = sram->dev->of_node, *child;
|
||
|
|
unsigned long size, cur_start, cur_size;
|
||
|
|
struct sram_reserve *rblocks, *block;
|
||
|
|
struct list_head reserve_list;
|
||
|
|
unsigned int nblocks, exports = 0;
|
||
|
|
const char *label;
|
||
|
|
int ret = 0;
|
||
|
|
|
||
|
|
INIT_LIST_HEAD(&reserve_list);
|
||
|
|
|
||
|
|
size = resource_size(res);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* We need an additional block to mark the end of the memory region
|
||
|
|
* after the reserved blocks from the dt are processed.
|
||
|
|
*/
|
||
|
|
nblocks = (np) ? of_get_available_child_count(np) + 1 : 1;
|
||
|
|
rblocks = kzalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL);
|
||
|
|
if (!rblocks)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
block = &rblocks[0];
|
||
|
|
for_each_available_child_of_node(np, child) {
|
||
|
|
struct resource child_res;
|
||
|
|
|
||
|
|
ret = of_address_to_resource(child, 0, &child_res);
|
||
|
|
if (ret < 0) {
|
||
|
|
dev_err(sram->dev,
|
||
|
|
"could not get address for node %s\n",
|
||
|
|
child->full_name);
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (child_res.start < res->start || child_res.end > res->end) {
|
||
|
|
dev_err(sram->dev,
|
||
|
|
"reserved block %s outside the sram area\n",
|
||
|
|
child->full_name);
|
||
|
|
ret = -EINVAL;
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
|
||
|
|
block->start = child_res.start - res->start;
|
||
|
|
block->size = resource_size(&child_res);
|
||
|
|
list_add_tail(&block->list, &reserve_list);
|
||
|
|
|
||
|
|
if (of_find_property(child, "export", NULL))
|
||
|
|
block->export = true;
|
||
|
|
|
||
|
|
if (of_find_property(child, "pool", NULL))
|
||
|
|
block->pool = true;
|
||
|
|
|
||
|
|
if ((block->export || block->pool) && block->size) {
|
||
|
|
exports++;
|
||
|
|
|
||
|
|
label = NULL;
|
||
|
|
ret = of_property_read_string(child, "label", &label);
|
||
|
|
if (ret && ret != -EINVAL) {
|
||
|
|
dev_err(sram->dev,
|
||
|
|
"%s has invalid label name\n",
|
||
|
|
child->full_name);
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
if (!label)
|
||
|
|
label = child->name;
|
||
|
|
|
||
|
|
block->label = devm_kstrdup(sram->dev,
|
||
|
|
label, GFP_KERNEL);
|
||
|
|
if (!block->label)
|
||
|
|
goto err_chunks;
|
||
|
|
|
||
|
|
dev_dbg(sram->dev, "found %sblock '%s' 0x%x-0x%x\n",
|
||
|
|
block->export ? "exported " : "", block->label,
|
||
|
|
block->start, block->start + block->size);
|
||
|
|
} else {
|
||
|
|
dev_dbg(sram->dev, "found reserved block 0x%x-0x%x\n",
|
||
|
|
block->start, block->start + block->size);
|
||
|
|
}
|
||
|
|
|
||
|
|
block++;
|
||
|
|
}
|
||
|
|
child = NULL;
|
||
|
|
|
||
|
|
/* the last chunk marks the end of the region */
|
||
|
|
rblocks[nblocks - 1].start = size;
|
||
|
|
rblocks[nblocks - 1].size = 0;
|
||
|
|
list_add_tail(&rblocks[nblocks - 1].list, &reserve_list);
|
||
|
|
|
||
|
|
list_sort(NULL, &reserve_list, sram_reserve_cmp);
|
||
|
|
|
||
|
|
if (exports) {
|
||
|
|
sram->partition = devm_kzalloc(sram->dev,
|
||
|
|
exports * sizeof(*sram->partition),
|
||
|
|
GFP_KERNEL);
|
||
|
|
if (!sram->partition) {
|
||
|
|
ret = -ENOMEM;
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
cur_start = 0;
|
||
|
|
list_for_each_entry(block, &reserve_list, list) {
|
||
|
|
/* can only happen if sections overlap */
|
||
|
|
if (block->start < cur_start) {
|
||
|
|
dev_err(sram->dev,
|
||
|
|
"block at 0x%x starts after current offset 0x%lx\n",
|
||
|
|
block->start, cur_start);
|
||
|
|
ret = -EINVAL;
|
||
|
|
sram_free_partitions(sram);
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ((block->export || block->pool) && block->size) {
|
||
|
|
ret = sram_add_partition(sram, block,
|
||
|
|
res->start + block->start);
|
||
|
|
if (ret) {
|
||
|
|
sram_free_partitions(sram);
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* current start is in a reserved block, so continue after it */
|
||
|
|
if (block->start == cur_start) {
|
||
|
|
cur_start = block->start + block->size;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* allocate the space between the current starting
|
||
|
|
* address and the following reserved block, or the
|
||
|
|
* end of the region.
|
||
|
|
*/
|
||
|
|
cur_size = block->start - cur_start;
|
||
|
|
|
||
|
|
dev_dbg(sram->dev, "adding chunk 0x%lx-0x%lx\n",
|
||
|
|
cur_start, cur_start + cur_size);
|
||
|
|
|
||
|
|
ret = gen_pool_add_virt(sram->pool,
|
||
|
|
(unsigned long)sram->virt_base + cur_start,
|
||
|
|
res->start + cur_start, cur_size, -1);
|
||
|
|
if (ret < 0) {
|
||
|
|
sram_free_partitions(sram);
|
||
|
|
goto err_chunks;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* next allocation after this reserved block */
|
||
|
|
cur_start = block->start + block->size;
|
||
|
|
}
|
||
|
|
|
||
|
|
err_chunks:
|
||
|
|
if (child)
|
||
|
|
of_node_put(child);
|
||
|
|
|
||
|
|
kfree(rblocks);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_probe(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
struct sram_dev *sram;
|
||
|
|
struct resource *res;
|
||
|
|
size_t size;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL);
|
||
|
|
if (!sram)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
sram->dev = &pdev->dev;
|
||
|
|
|
||
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||
|
|
if (!res) {
|
||
|
|
dev_err(sram->dev, "found no memory resource\n");
|
||
|
|
return -EINVAL;
|
||
|
|
}
|
||
|
|
|
||
|
|
size = resource_size(res);
|
||
|
|
|
||
|
|
if (!devm_request_mem_region(sram->dev, res->start, size, pdev->name)) {
|
||
|
|
dev_err(sram->dev, "could not request region for resource\n");
|
||
|
|
return -EBUSY;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (of_property_read_bool(pdev->dev.of_node, "no-memory-wc"))
|
||
|
|
sram->virt_base = devm_ioremap(sram->dev, res->start, size);
|
||
|
|
else
|
||
|
|
sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size);
|
||
|
|
if (!sram->virt_base)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
sram->pool = devm_gen_pool_create(sram->dev, ilog2(SRAM_GRANULARITY),
|
||
|
|
NUMA_NO_NODE, NULL);
|
||
|
|
if (IS_ERR(sram->pool))
|
||
|
|
return PTR_ERR(sram->pool);
|
||
|
|
|
||
|
|
ret = sram_reserve_regions(sram, res);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
sram->clk = devm_clk_get(sram->dev, NULL);
|
||
|
|
if (IS_ERR(sram->clk))
|
||
|
|
sram->clk = NULL;
|
||
|
|
else
|
||
|
|
clk_prepare_enable(sram->clk);
|
||
|
|
|
||
|
|
platform_set_drvdata(pdev, sram);
|
||
|
|
|
||
|
|
dev_dbg(sram->dev, "SRAM pool: %zu KiB @ 0x%p\n",
|
||
|
|
gen_pool_size(sram->pool) / 1024, sram->virt_base);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sram_remove(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
struct sram_dev *sram = platform_get_drvdata(pdev);
|
||
|
|
|
||
|
|
sram_free_partitions(sram);
|
||
|
|
|
||
|
|
if (gen_pool_avail(sram->pool) < gen_pool_size(sram->pool))
|
||
|
|
dev_err(sram->dev, "removed while SRAM allocated\n");
|
||
|
|
|
||
|
|
if (sram->clk)
|
||
|
|
clk_disable_unprepare(sram->clk);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef CONFIG_OF
|
||
|
|
static const struct of_device_id sram_dt_ids[] = {
|
||
|
|
{ .compatible = "mmio-sram" },
|
||
|
|
{}
|
||
|
|
};
|
||
|
|
#endif
|
||
|
|
|
||
|
|
static struct platform_driver sram_driver = {
|
||
|
|
.driver = {
|
||
|
|
.name = "sram",
|
||
|
|
.of_match_table = of_match_ptr(sram_dt_ids),
|
||
|
|
},
|
||
|
|
.probe = sram_probe,
|
||
|
|
.remove = sram_remove,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int __init sram_init(void)
|
||
|
|
{
|
||
|
|
return platform_driver_register(&sram_driver);
|
||
|
|
}
|
||
|
|
|
||
|
|
postcore_initcall(sram_init);
|