1 files changed, 256 insertions, 69 deletions

diff --git a/kernel/drivers/misc/sram.c b/kernel/drivers/misc/sram.c
index eeaaf5fca..736dae715 100644
--- a/kernel/drivers/misc/sram.c
+++ b/kernel/drivers/misc/sram.c
@@ -18,33 +18,154 @@
  * MA 02110-1301, USA.
  */
 
-#include <linux/kernel.h>
-#include <linux/init.h>
 #include <linux/clk.h>
-#include <linux/err.h>
+#include <linux/genalloc.h>
 #include <linux/io.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/list.h>
 #include <linux/list_sort.h>
+#include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/genalloc.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)
 {
@@ -54,62 +175,28 @@ static int sram_reserve_cmp(void *priv, struct list_head *a,
 	return ra->start - rb->start;
 }
 
-static int sram_probe(struct platform_device *pdev)
+static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
 {
-	void __iomem *virt_base;
-	struct sram_dev *sram;
-	struct resource *res;
-	struct device_node *np = pdev->dev.of_node, *child;
+	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;
-	int ret;
+	unsigned int nblocks, exports = 0;
+	const char *label;
+	int ret = 0;
 
 	INIT_LIST_HEAD(&reserve_list);
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_err(&pdev->dev, "found no memory resource\n");
-		return -EINVAL;
-	}
-
 	size = resource_size(res);
 
-	if (!devm_request_mem_region(&pdev->dev,
-			res->start, size, pdev->name)) {
-		dev_err(&pdev->dev, "could not request region for resource\n");
-		return -EBUSY;
-	}
-
-	virt_base = devm_ioremap_wc(&pdev->dev, res->start, size);
-	if (IS_ERR(virt_base))
-		return PTR_ERR(virt_base);
-
-	sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL);
-	if (!sram)
-		return -ENOMEM;
-
-	sram->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(sram->clk))
-		sram->clk = NULL;
-	else
-		clk_prepare_enable(sram->clk);
-
-	sram->pool = devm_gen_pool_create(&pdev->dev, ilog2(SRAM_GRANULARITY), -1);
-	if (!sram->pool)
-		return -ENOMEM;
-
 	/*
 	 * 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 = kmalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL);
-	if (!rblocks) {
-		ret = -ENOMEM;
-		goto err_alloc;
-	}
+	rblocks = kzalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL);
+	if (!rblocks)
+		return -ENOMEM;
 
 	block = &rblocks[0];
 	for_each_available_child_of_node(np, child) {
@@ -117,14 +204,14 @@ static int sram_probe(struct platform_device *pdev)
 
 		ret = of_address_to_resource(child, 0, &child_res);
 		if (ret < 0) {
-			dev_err(&pdev->dev,
+			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(&pdev->dev,
+			dev_err(sram->dev,
 				"reserved block %s outside the sram area\n",
 				child->full_name);
 			ret = -EINVAL;
@@ -135,12 +222,42 @@ static int sram_probe(struct platform_device *pdev)
 		block->size = resource_size(&child_res);
 		list_add_tail(&block->list, &reserve_list);
 
-		dev_dbg(&pdev->dev, "found reserved block 0x%x-0x%x\n",
-			block->start,
-			block->start + block->size);
+		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;
@@ -149,18 +266,37 @@ static int sram_probe(struct platform_device *pdev)
 
 	list_sort(NULL, &reserve_list, sram_reserve_cmp);
 
-	cur_start = 0;
+	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(&pdev->dev,
+			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;
@@ -174,40 +310,91 @@ static int sram_probe(struct platform_device *pdev)
 		 */
 		cur_size = block->start - cur_start;
 
-		dev_dbg(&pdev->dev, "adding chunk 0x%lx-0x%lx\n",
+		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)virt_base + cur_start,
+				(unsigned long)sram->virt_base + cur_start,
 				res->start + cur_start, cur_size, -1);
-		if (ret < 0)
+		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;
+	}
+
+	sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size);
+	if (IS_ERR(sram->virt_base))
+		return PTR_ERR(sram->virt_base);
+
+	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(&pdev->dev, "SRAM pool: %ld KiB @ 0x%p\n", size / 1024, virt_base);
+	dev_dbg(sram->dev, "SRAM pool: %zu KiB @ 0x%p\n",
+		gen_pool_size(sram->pool) / 1024, sram->virt_base);
 
 	return 0;
-
-err_chunks:
-	kfree(rblocks);
-err_alloc:
-	if (sram->clk)
-		clk_disable_unprepare(sram->clk);
-	return ret;
 }
 
 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_dbg(&pdev->dev, "removed while SRAM allocated\n");
+		dev_err(sram->dev, "removed while SRAM allocated\n");
 
 	if (sram->clk)
 		clk_disable_unprepare(sram->clk);