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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 22:15:15 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 22:15:15 -0800
commit8e483ed1342a4ea45b70f0f33ac54eff7a33d918 (patch)
tree66c9f9ad196581966bdb06802e11e9856b1c0779 /drivers/misc/sram.c
parente880e87488d5bbf630dd716e6de8a53585614568 (diff)
parente2d8680741edec84f843f783a7f4a44418b818d7 (diff)
downloadlinux-8e483ed1342a4ea45b70f0f33ac54eff7a33d918.tar.bz2
Merge tag 'char-misc-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH: "Here is the big char/misc driver update for 4.4-rc1. Lots of different driver and subsystem updates, hwtracing being the largest with the addition of some new platforms that are now supported. Full details in the shortlog. All of these have been in linux-next for a long time with no reported issues" * tag 'char-misc-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (181 commits) fpga: socfpga: Fix check of return value of devm_request_irq lkdtm: fix ACCESS_USERSPACE test mcb: Destroy IDA on module unload mcb: Do not return zero on error path in mcb_pci_probe() mei: bus: set the device name before running fixup mei: bus: use correct lock ordering mei: Fix debugfs filename in error output char: ipmi: ipmi_ssif: Replace timeval with timespec64 fpga: zynq-fpga: Fix issue with drvdata being overwritten. fpga manager: remove unnecessary null pointer checks fpga manager: ensure lifetime with of_fpga_mgr_get fpga: zynq-fpga: Change fw format to handle bin instead of bit. fpga: zynq-fpga: Fix unbalanced clock handling misc: sram: partition base address belongs to __iomem space coresight: etm3x: adding documentation for sysFS's cpu interface vme: 8-bit status/id takes 256 values, not 255 fpga manager: Adding FPGA Manager support for Xilinx Zynq 7000 ARM: zynq: dt: Updated devicetree for Zynq 7000 platform. ARM: dt: fpga: Added binding docs for Xilinx Zynq FPGA manager. ver_linux: proc/modules, limit text processing to 'sed' ...
Diffstat (limited to 'drivers/misc/sram.c')
-rw-r--r--drivers/misc/sram.c196
1 files changed, 188 insertions, 8 deletions
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
index 431e1dd528bc..736dae715dbf 100644
--- a/drivers/misc/sram.c
+++ b/drivers/misc/sram.c
@@ -28,20 +28,144 @@
#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");