/* * 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/delay.h>#include <linux/genalloc.h>#include <linux/io.h>#include <linux/list_sort.h>#include <linux/of_address.h>#include <linux/of_device.h>#include <linux/platform_device.h>#include <linux/regmap.h>#include <linux/slab.h>#include <linux/mfd/syscon.h>#include <soc/at91/atmel-secumod.h> #include "sram.h" #define SRAM_GRANULARITY	32 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;	}	if (block->protect_exec) {		ret = sram_check_protect_exec(sram, block, part);		if (ret)			return ret; 		ret = sram_add_pool(sram, block, start, part);		if (ret)			return ret; 		sram_add_protect_exec(part);	} 	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 (of_find_property(child, "protect-exec", NULL))			block->protect_exec = true; 		if ((block->export || block->pool || block->protect_exec) &&		    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) {				ret = -ENOMEM;				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->protect_exec) &&		    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 atmel_securam_wait(void){	struct regmap *regmap;	u32 val; 	regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-secumod");	if (IS_ERR(regmap))		return -ENODEV; 	return regmap_read_poll_timeout(regmap, AT91_SECUMOD_RAMRDY, val,					val & AT91_SECUMOD_RAMRDY_READY,					10000, 500000);} static const struct of_device_id sram_dt_ids[] = {	{ .compatible = "mmio-sram" },	{ .compatible = "atmel,sama5d2-securam", .data = atmel_securam_wait },	{}}; static int sram_probe(struct platform_device *pdev){	struct sram_dev *sram;	struct resource *res;	size_t size;	int ret;	int (*init_func)(void); 	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); 	init_func = of_device_get_match_data(&pdev->dev);	if (init_func) {		ret = init_func();		if (ret)			return ret;	} 	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;} static struct platform_driver sram_driver = {	.driver = {		.name = "sram",		.of_match_table = 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);