1 files changed, 141 insertions, 0 deletions
diff --git a/disk/disk-uclass.c b/disk/disk-uclass.c
new file mode 100644
index 00000000000..ee3cc4407d7
--- /dev/null
+++ b/disk/disk-uclass.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Software partition device (UCLASS_PARTITION)
+ *
+ *  Copyright (c) 2021 Linaro Limited
+ *			Author: AKASHI Takahiro
+ */
+
+#define LOG_CATEGORY UCLASS_PARTITION
+
+#include <blk.h>
+#include <dm.h>
+#include <log.h>
+#include <part.h>
+#include <vsprintf.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+
+/**
+ * disk_blk_part_validate() - Check whether access to partition is within limits
+ *
+ * @dev: Device (partition udevice)
+ * @start: Start block for the access(from start of partition)
+ * @blkcnt: Number of blocks to access (within the partition)
+ * @return 0 on valid block range, or -ve on error.
+ */
+static int disk_blk_part_validate(struct udevice *dev, lbaint_t start, lbaint_t blkcnt)
+{
+	struct disk_part *part = dev_get_uclass_plat(dev);
+
+	if (device_get_uclass_id(dev) != UCLASS_PARTITION)
+		return -ENOSYS;
+
+	if (start >= part->gpt_part_info.size)
+		return -E2BIG;
+
+	if ((start + blkcnt) > part->gpt_part_info.size)
+		return -ERANGE;
+
+	return 0;
+}
+
+/**
+ * disk_blk_part_offset() - Compute offset from start of block device
+ *
+ * @dev: Device (partition udevice)
+ * @start: Start block for the access (from start of partition)
+ * @return Start block for the access (from start of block device)
+ */
+static lbaint_t disk_blk_part_offset(struct udevice *dev, lbaint_t start)
+{
+	struct disk_part *part = dev_get_uclass_plat(dev);
+
+	return start + part->gpt_part_info.start;
+}
+
+/*
+ * BLOCK IO APIs
+ */
+/**
+ * disk_blk_read() - Read from a block device partition
+ *
+ * @dev: Device to read from (partition udevice)
+ * @start: Start block for the read (from start of partition)
+ * @blkcnt: Number of blocks to read (within the partition)
+ * @buffer: Place to put the data
+ * @return number of blocks read (which may be less than @blkcnt),
+ * or -ve on error. This never returns 0 unless @blkcnt is 0
+ */
+unsigned long disk_blk_read(struct udevice *dev, lbaint_t start,
+			    lbaint_t blkcnt, void *buffer)
+{
+	int ret = disk_blk_part_validate(dev, start, blkcnt);
+
+	if (ret)
+		return ret;
+
+	return blk_read(dev_get_parent(dev), disk_blk_part_offset(dev, start),
+			blkcnt, buffer);
+}
+
+/**
+ * disk_blk_write() - Write to a block device
+ *
+ * @dev: Device to write to (partition udevice)
+ * @start: Start block for the write (from start of partition)
+ * @blkcnt: Number of blocks to write (within the partition)
+ * @buffer: Data to write
+ * @return number of blocks written (which may be less than @blkcnt),
+ * or -ve on error. This never returns 0 unless @blkcnt is 0
+ */
+unsigned long disk_blk_write(struct udevice *dev, lbaint_t start,
+			     lbaint_t blkcnt, const void *buffer)
+{
+	int ret = disk_blk_part_validate(dev, start, blkcnt);
+
+	if (ret)
+		return ret;
+
+	return blk_write(dev_get_parent(dev), disk_blk_part_offset(dev, start),
+			 blkcnt, buffer);
+}
+
+/**
+ * disk_blk_erase() - Erase part of a block device
+ *
+ * @dev: Device to erase (partition udevice)
+ * @start: Start block for the erase (from start of partition)
+ * @blkcnt: Number of blocks to erase (within the partition)
+ * @return number of blocks erased (which may be less than @blkcnt),
+ * or -ve on error. This never returns 0 unless @blkcnt is 0
+ */
+unsigned long disk_blk_erase(struct udevice *dev, lbaint_t start,
+			     lbaint_t blkcnt)
+{
+	int ret = disk_blk_part_validate(dev, start, blkcnt);
+
+	if (ret)
+		return ret;
+
+	return blk_erase(dev_get_parent(dev), disk_blk_part_offset(dev, start),
+			 blkcnt);
+}
+
+UCLASS_DRIVER(partition) = {
+	.id		= UCLASS_PARTITION,
+	.per_device_plat_auto	= sizeof(struct disk_part),
+	.name		= "partition",
+};
+
+static const struct blk_ops blk_part_ops = {
+	.read	= disk_blk_read,
+	.write	= disk_blk_write,
+	.erase	= disk_blk_erase,
+};
+
+U_BOOT_DRIVER(blk_partition) = {
+	.name		= "blk_partition",
+	.id		= UCLASS_PARTITION,
+	.ops		= &blk_part_ops,
+};