Merge branch '2023-06-09-fwu-updates' into next

Two sets of FWU updates from Jassi Brar.  First:
The patchset reduces ~400 lines of code, while keeping the functionality same and making
meta-data operations much faster (by using cached structures).

Issue:
meta-data copies (primary and secondary) are being handled by the
backend/storage layer instead of the common core in fwu.c (as also noted by
Ilias)  that is, gpt_blk.c manages meta-data and similarly raw_mtd.c will have
to do the same when it arrives. The code could by make smaller, cleaner and
optimised.

Basic idea:
Introduce  .read_mdata() and .write_mdata() in fwu_mdata_ops  that simply
read/write meta-data copy. The core code takes care of integrity and redundancy
of the meta-data, as a result we can get rid of every other callback
.get_mdata() .update_mdata() .get_mdata_part_num()  .read_mdata_partition()
.write_mdata_partition() and the corresponding wrapper functions thereby making
the code 100s of LOC smaller.

Get rid of fwu_check_mdata_validity() and fwu_mdata_check() which expected
underlying layer to manage and verify mdata copies.
Implement  fwu_get_verified_mdata(struct fwu_mdata *mdata) public function that
reads, verifies and, if needed, fixes the meta-data copies.

Verified copy of meta-data is now cached as 'g_mdata' in fwu.c, which avoids
multiple low-level expensive read and parse calls.
gpt meta-data partition numbers are now cached in gpt_blk.c, so that we don't
have to do expensive part_get_info() and uid ops.

And second:
Introduce support for mtd backed storage for FWU feature and enable it on
Synquacer platform based DeveloperBox.

1 files changed, 10 insertions, 141 deletions

diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c b/drivers/fwu-mdata/fwu-mdata-uclass.c
index b477e9603fb..0a8edaaa418 100644
--- a/drivers/fwu-mdata/fwu-mdata-uclass.c
+++ b/drivers/fwu-mdata/fwu-mdata-uclass.c
@@ -14,170 +14,39 @@
 
 #include <linux/errno.h>
 #include <linux/types.h>
-#include <u-boot/crc.h>
 
 /**
- * fwu_get_mdata_part_num() - Get the FWU metadata partition numbers
- * @dev: FWU metadata device
- * @mdata_parts: array for storing the metadata partition numbers
- *
- * Get the partition numbers on the storage device on which the
- * FWU metadata is stored. Two partition numbers will be returned.
- *
- * Return: 0 if OK, -ve on error
- *
- */
-int fwu_get_mdata_part_num(struct udevice *dev, uint *mdata_parts)
-{
-	const struct fwu_mdata_ops *ops = device_get_ops(dev);
-
-	if (!ops->get_mdata_part_num) {
-		log_debug("get_mdata_part_num() method not defined\n");
-		return -ENOSYS;
-	}
-
-	return ops->get_mdata_part_num(dev, mdata_parts);
-}
-
-/**
- * fwu_read_mdata_partition() - Read the FWU metadata from a partition
- * @dev: FWU metadata device
- * @mdata: Copy of the FWU metadata
- * @part_num: Partition number from which FWU metadata is to be read
- *
- * Read the FWU metadata from the specified partition number
- *
- * Return: 0 if OK, -ve on error
- *
- */
-int fwu_read_mdata_partition(struct udevice *dev, struct fwu_mdata *mdata,
-			     uint part_num)
-{
-	const struct fwu_mdata_ops *ops = device_get_ops(dev);
-
-	if (!ops->read_mdata_partition) {
-		log_debug("read_mdata_partition() method not defined\n");
-		return -ENOSYS;
-	}
-
-	return ops->read_mdata_partition(dev, mdata, part_num);
-}
-
-/**
- * fwu_write_mdata_partition() - Write the FWU metadata to a partition
- * @dev: FWU metadata device
- * @mdata: Copy of the FWU metadata
- * @part_num: Partition number to which FWU metadata is to be written
- *
- * Write the FWU metadata to the specified partition number
- *
- * Return: 0 if OK, -ve on error
- *
- */
-int fwu_write_mdata_partition(struct udevice *dev, struct fwu_mdata *mdata,
-			      uint part_num)
-{
-	const struct fwu_mdata_ops *ops = device_get_ops(dev);
-
-	if (!ops->write_mdata_partition) {
-		log_debug("write_mdata_partition() method not defined\n");
-		return -ENOSYS;
-	}
-
-	return ops->write_mdata_partition(dev, mdata, part_num);
-}
-
-/**
- * fwu_mdata_check() - Check if the FWU metadata is valid
- * @dev: FWU metadata device
- *
- * Validate both copies of the FWU metadata. If one of the copies
- * has gone bad, restore it from the other copy.
- *
- * Return: 0 if OK, -ve on error
- *
- */
-int fwu_mdata_check(struct udevice *dev)
-{
-	const struct fwu_mdata_ops *ops = device_get_ops(dev);
-
-	if (!ops->check_mdata) {
-		log_debug("check_mdata() method not defined\n");
-		return -ENOSYS;
-	}
-
-	return ops->check_mdata(dev);
-}
-
-/**
- * fwu_get_mdata() - Get a FWU metadata copy
- * @dev: FWU metadata device
- * @mdata: Copy of the FWU metadata
- *
- * Get a valid copy of the FWU metadata.
- *
- * Note: This function is to be called first when modifying any fields
- * in the metadata. The sequence of calls to modify any field in the
- * metadata would  be 1) fwu_get_mdata 2) Modify metadata, followed by
- * 3) fwu_update_mdata
+ * fwu_read_mdata() - Wrapper around fwu_mdata_ops.read_mdata()
  *
  * Return: 0 if OK, -ve on error
- *
  */
-int fwu_get_mdata(struct udevice *dev, struct fwu_mdata *mdata)
+int fwu_read_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary)
 {
 	const struct fwu_mdata_ops *ops = device_get_ops(dev);
 
-	if (!ops->get_mdata) {
-		log_debug("get_mdata() method not defined\n");
+	if (!ops->read_mdata) {
+		log_debug("read_mdata() method not defined\n");
 		return -ENOSYS;
 	}
 
-	return ops->get_mdata(dev, mdata);
+	return ops->read_mdata(dev, mdata, primary);
 }
 
 /**
- * fwu_update_mdata() - Update the FWU metadata
- * @dev: FWU metadata device
- * @mdata: Copy of the FWU metadata
- *
- * Update the FWU metadata structure by writing to the
- * FWU metadata partitions.
- *
- * Note: This function is not to be called directly to update the
- * metadata fields. The sequence of function calls should be
- * 1) fwu_get_mdata() 2) Modify the medata fields 3) fwu_update_mdata()
- *
- * The sequence of updating the partitions should be, update the
- * primary metadata partition (first partition encountered), followed
- * by updating the secondary partition. With this update sequence, in
- * the rare scenario that the two metadata partitions are valid but do
- * not match, maybe due to power outage at the time of updating the
- * metadata copies, the secondary partition can be updated from the
- * primary.
+ * fwu_write_mdata() - Wrapper around fwu_mdata_ops.write_mdata()
  *
  * Return: 0 if OK, -ve on error
- *
  */
-int fwu_update_mdata(struct udevice *dev, struct fwu_mdata *mdata)
+int fwu_write_mdata(struct udevice *dev, struct fwu_mdata *mdata, bool primary)
 {
-	void *buf;
 	const struct fwu_mdata_ops *ops = device_get_ops(dev);
 
-	if (!ops->update_mdata) {
-		log_debug("get_mdata() method not defined\n");
+	if (!ops->write_mdata) {
+		log_debug("write_mdata() method not defined\n");
 		return -ENOSYS;
 	}
 
-	/*
-	 * Calculate the crc32 for the updated FWU metadata
-	 * and put the updated value in the FWU metadata crc32
-	 * field
-	 */
-	buf = &mdata->version;
-	mdata->crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32));
-
-	return ops->update_mdata(dev, mdata);
+	return ops->write_mdata(dev, mdata, primary);
 }
 
 UCLASS_DRIVER(fwu_mdata) = {