[RFC 10/22] dm: blk: add read/write interfaces with udevice

AKASHI Takahiro
2021-10-01T05:06:36Z

In include/blk.h, Simon suggested:
===>
/*
* These functions should take struct udevice instead of struct blk_desc,
* but this is convenient for migration to driver model. Add a 'd' prefix
* to the function operations, so that blk_read(), etc. can be reserved for
* functions with the correct arguments.
*/
unsigned long blk_dread(struct blk_desc *block_dev, lbaint_t start,
lbaint_t blkcnt, void *buffer);
unsigned long blk_dwrite(struct blk_desc *block_dev, lbaint_t start,
lbaint_t blkcnt, const void *buffer);
unsigned long blk_derase(struct blk_desc *block_dev, lbaint_t start,
lbaint_t blkcnt);
<===

So new interfaces are provided with this patch.

They are expected to be used everywhere in U-Boot at the end. The exceptions
are block device drivers, partition drivers and efi_disk which should know
details of blk_desc structure.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
drivers/block/blk-uclass.c | 91 ++++++++++++++++++++++++++++++++++++++
include/blk.h | 6 +++
2 files changed, 97 insertions(+)

diff --git a/drivers/block/blk-uclass.c b/drivers/block/blk-uclass.c
index 6ba11a8fa7f7..8fbec8779e1e 100644
--- a/drivers/block/blk-uclass.c
+++ b/drivers/block/blk-uclass.c
@@ -482,6 +482,97 @@ unsigned long blk_derase(struct blk_desc *block_dev, lbaint_t start,
return ops->erase(dev, start, blkcnt);
}

+static struct blk_desc *dev_get_blk(struct udevice *dev)
+{
+ struct blk_desc *block_dev;
+
+ switch (device_get_uclass_id(dev)) {
+ case UCLASS_BLK:
+ block_dev = dev_get_uclass_plat(dev);
+ break;
+ case UCLASS_PARTITION:
+ block_dev = dev_get_uclass_plat(dev_get_parent(dev));
+ break;
+ default:
+ block_dev = NULL;
+ break;
+ }
+
+ return block_dev;
+}
+
+unsigned long blk_read(struct udevice *dev, lbaint_t start,
+ lbaint_t blkcnt, void *buffer)
+{
+ struct blk_desc *block_dev;
+ const struct blk_ops *ops;
+ struct disk_part *part;
+ lbaint_t start_in_disk;
+ ulong blks_read;
+
+ block_dev = dev_get_blk(dev);
+ if (!block_dev)
+ return -ENOSYS;
+
+ ops = blk_get_ops(dev);
+ if (!ops->read)
+ return -ENOSYS;
+
+ start_in_disk = start;
+ if (device_get_uclass_id(dev) == UCLASS_PARTITION) {
+ part = dev_get_uclass_plat(dev);
+ start_in_disk += part->gpt_part_info.start;
+ }
+
+ if (blkcache_read(block_dev->if_type, block_dev->devnum,
+ start_in_disk, blkcnt, block_dev->blksz, buffer))
+ return blkcnt;
+ blks_read = ops->read(dev, start, blkcnt, buffer);
+ if (blks_read == blkcnt)
+ blkcache_fill(block_dev->if_type, block_dev->devnum,
+ start_in_disk, blkcnt, block_dev->blksz, buffer);
+
+ return blks_read;
+}
+
+unsigned long blk_write(struct udevice *dev, lbaint_t start,
+ lbaint_t blkcnt, const void *buffer)
+{
+ struct blk_desc *block_dev;
+ const struct blk_ops *ops;
+
+ block_dev = dev_get_blk(dev);
+ if (!block_dev)
+ return -ENOSYS;
+
+ ops = blk_get_ops(dev);
+ if (!ops->write)
+ return -ENOSYS;
+
+ blkcache_invalidate(block_dev->if_type, block_dev->devnum);
+
+ return ops->write(dev, start, blkcnt, buffer);
+}
+
+unsigned long blk_erase(struct udevice *dev, lbaint_t start,
+ lbaint_t blkcnt)
+{
+ struct blk_desc *block_dev;
+ const struct blk_ops *ops;
+
+ block_dev = dev_get_blk(dev);
+ if (!block_dev)
+ return -ENOSYS;
+
+ ops = blk_get_ops(dev);
+ if (!ops->erase)
+ return -ENOSYS;
+
+ blkcache_invalidate(block_dev->if_type, block_dev->devnum);
+
+ return ops->erase(dev, start, blkcnt);
+}
+
int blk_get_from_parent(struct udevice *parent, struct udevice **devp)
{
struct udevice *dev;
diff --git a/include/blk.h b/include/blk.h
index 3d883eb1db64..f5fdd6633a09 100644
--- a/include/blk.h
+++ b/include/blk.h
@@ -284,6 +284,12 @@ unsigned long blk_dwrite(struct blk_desc *block_dev, lbaint_t start,
unsigned long blk_derase(struct blk_desc *block_dev, lbaint_t start,
lbaint_t blkcnt);

+unsigned long blk_read(struct udevice *dev, lbaint_t start,
+ lbaint_t blkcnt, void *buffer);
+unsigned long blk_write(struct udevice *dev, lbaint_t start,
+ lbaint_t blkcnt, const void *buffer);
+unsigned long blk_erase(struct udevice *dev, lbaint_t start,
+ lbaint_t blkcnt);
/**
* blk_find_device() - Find a block device
*
--
2.33.0