Merge tag 'phy-for-4.4-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/kishon...
[firefly-linux-kernel-4.4.55.git] / drivers / misc / sram.c
index 431e1dd528bcb8dd0d662eec74bdc865d663dd4c..736dae715dbf751c4b03eeaae1cd629c422aba96 100644 (file)
 
 #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)
 {
@@ -57,7 +181,8 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
        unsigned long size, cur_start, cur_size;
        struct sram_reserve *rblocks, *block;
        struct list_head reserve_list;
-       unsigned int nblocks;
+       unsigned int nblocks, exports = 0;
+       const char *label;
        int ret = 0;
 
        INIT_LIST_HEAD(&reserve_list);
@@ -69,7 +194,7 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
         * 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);
+       rblocks = kzalloc((nblocks) * sizeof(*rblocks), GFP_KERNEL);
        if (!rblocks)
                return -ENOMEM;
 
@@ -82,7 +207,6 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
                        dev_err(sram->dev,
                                "could not get address for node %s\n",
                                child->full_name);
-                       of_node_put(child);
                        goto err_chunks;
                }
 
@@ -91,7 +215,6 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
                                "reserved block %s outside the sram area\n",
                                child->full_name);
                        ret = -EINVAL;
-                       of_node_put(child);
                        goto err_chunks;
                }
 
@@ -99,11 +222,42 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
                block->size = resource_size(&child_res);
                list_add_tail(&block->list, &reserve_list);
 
-               dev_dbg(sram->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;
@@ -112,8 +266,17 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
 
        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) {
@@ -121,9 +284,19 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
                                "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;
@@ -143,14 +316,19 @@ static int sram_reserve_regions(struct sram_dev *sram, struct resource *res)
                ret = gen_pool_add_virt(sram->pool,
                                (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;
@@ -213,6 +391,8 @@ 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");