diff mbox series

[v15,03/15] FWU: Add FWU metadata access driver for GPT partitioned block devices

Message ID 20221021124608.681387-4-sughosh.ganu@linaro.org
State Accepted
Commit 554b38f7a532784c72e57f58877fdd922b7a0d9f
Headers show
Series FWU: Add FWU Multi Bank Update feature support | expand

Commit Message

Sughosh Ganu Oct. 21, 2022, 12:45 p.m. UTC 
In the FWU Multi Bank Update feature, the information about the
updatable images is stored as part of the metadata, on a separate
partition. Add a driver for reading from and writing to the metadata
when the updatable images and the metadata are stored on a block
device which is formatted with GPT based partition scheme.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
---
Changes since V14:
* Remove the check for nparts while iterating over the partitions as
  suggested by Ilias
* Drop the superfluous braces in gpt_get_mdata_disk_part()
* Add a NULL check for mdata in gpt_read_write_mdata()  as
  suggested by Ilias

 drivers/fwu-mdata/Kconfig   |  16 ++
 drivers/fwu-mdata/Makefile  |   8 +
 drivers/fwu-mdata/gpt_blk.c | 290 ++++++++++++++++++++++++++++++++++++
 include/fwu.h               |   4 +
 4 files changed, 318 insertions(+)
 create mode 100644 drivers/fwu-mdata/Kconfig
 create mode 100644 drivers/fwu-mdata/Makefile
 create mode 100644 drivers/fwu-mdata/gpt_blk.c

Comments

Ilias Apalodimas Oct. 21, 2022, 3:03 p.m. UTC | #1 
Hi Sughosh

> +{
> +	int ret;
> +	u32 len, blk_start, blkcnt;
> +	struct disk_partition info;
> +
> +	ALLOC_CACHE_ALIGN_BUFFER_PAD(struct fwu_mdata, mdata_aligned, 1,
> +				     desc->blksz);
> +
> +	if (!mdata)
> +		return -ENOMEM;

ENOMEM is usually for allocation failures this is an -EINVAL

> +
> +	ret = gpt_get_mdata_disk_part(desc, &info, part_num);
> +	if (ret < 0) {
> +		printf("Unable to get the FWU metadata partition\n");
> +		return -ENOENT;
> +	}
> +
> +	len = sizeof(*mdata);
> +	blkcnt = BLOCK_CNT(len, desc);
> +	if (blkcnt > info.size) {
> +		log_debug("Block count exceeds FWU metadata partition size\n");
> +		return -ERANGE;
> +	}
> +
> +	blk_start = info.start;
> +	if (access == MDATA_READ) {
> +		if (blk_dread(desc, blk_start, blkcnt, mdata_aligned) != blkcnt) {
> +			log_debug("Error reading FWU metadata from the device\n");
> +			return -EIO;
> +		}
> +		memcpy(mdata, mdata_aligned, sizeof(struct fwu_mdata));
> +	} else {

else if ?

> +		if (blk_dwrite(desc, blk_start, blkcnt, mdata) != blkcnt) {
> +			log_debug("Error writing FWU metadata to the device\n");
> +			return -EIO;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int fwu_gpt_update_mdata(struct udevice *dev, struct fwu_mdata *mdata)
> +{
> +	int ret;
> +	struct blk_desc *desc;
> +	uint mdata_parts[2];
> +	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> +
> +	desc = dev_get_uclass_plat(priv->blk_dev);

dev_get_uclass_plat might return NULL,  gpt_read_write_mdata() doesn't check
against NULL and then it ends up calling gpt_get_mdata_disk_part() which
then calls part_get_info().  I don't think anyone checks for the desc ptr

And I think this is a problem  overall in all the callbacks belowe that
invoke dev_get_uclass_plat()

> +
> +	ret = gpt_get_mdata_partitions(desc, mdata_parts);
> +	if (ret < 0) {
> +		log_debug("Error getting the FWU metadata partitions\n");
> +		return -ENOENT;
> +	}
> +
> +	/* First write the primary partition */
> +	ret = gpt_read_write_mdata(desc, mdata, MDATA_WRITE, mdata_parts[0]);
> +	if (ret < 0) {
> +		log_debug("Updating primary FWU metadata partition failed\n");
> +		return ret;
> +	}
> +
> +	/* And now the replica */
> +	ret = gpt_read_write_mdata(desc, mdata, MDATA_WRITE, mdata_parts[1]);
> +	if (ret < 0) {
> +		log_debug("Updating secondary FWU metadata partition failed\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int gpt_get_mdata(struct blk_desc *desc, struct fwu_mdata *mdata)
> +{
> +	int ret;
> +	uint mdata_parts[2];
> +
> +	ret = gpt_get_mdata_partitions(desc, mdata_parts);
> +
> +	if (ret < 0) {
> +		log_debug("Error getting the FWU metadata partitions\n");
> +		return -ENOENT;
> +	}
> +
> +	ret = gpt_read_write_mdata(desc, mdata, MDATA_READ, mdata_parts[0]);
> +	if (ret < 0) {
> +		log_debug("Failed to read the FWU metadata from the device\n");
> +		return -EIO;
> +	}
> +
> +	ret = fwu_verify_mdata(mdata, 1);
> +	if (!ret)
> +		return 0;
> +
> +	/*
> +	 * Verification of the primary FWU metadata copy failed.
> +	 * Try to read the replica.
> +	 */
> +	memset(mdata, '\0', sizeof(struct fwu_mdata));
> +	ret = gpt_read_write_mdata(desc, mdata, MDATA_READ, mdata_parts[1]);
> +	if (ret < 0) {
> +		log_debug("Failed to read the FWU metadata from the device\n");
> +		return -EIO;
> +	}
> +
> +	ret = fwu_verify_mdata(mdata, 0);
> +	if (!ret)
> +		return 0;
> +
> +	/* Both the FWU metadata copies are corrupted. */
> +	return -EIO;
> +}
> +
> +static int fwu_gpt_get_mdata(struct udevice *dev, struct fwu_mdata *mdata)
> +{
> +	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> +
> +	return gpt_get_mdata(dev_get_uclass_plat(priv->blk_dev), mdata);
> +}
> +
> +static int fwu_gpt_get_mdata_partitions(struct udevice *dev, uint *mdata_parts)
> +{
> +	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> +
> +	return gpt_get_mdata_partitions(dev_get_uclass_plat(priv->blk_dev),
> +					mdata_parts);
> +}
> +
> +static int fwu_gpt_read_mdata_partition(struct udevice *dev,
> +					struct fwu_mdata *mdata, uint part_num)
> +{
> +	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> +
> +	return gpt_read_write_mdata(dev_get_uclass_plat(priv->blk_dev),
> +				    mdata, MDATA_READ, part_num);
> +}
> +
> +static int fwu_gpt_write_mdata_partition(struct udevice *dev,
> +					struct fwu_mdata *mdata, uint part_num)
> +{
> +	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> +
> +	return gpt_read_write_mdata(dev_get_uclass_plat(priv->blk_dev),
> +				    mdata, MDATA_WRITE, part_num);
> +}
> +
> +static int fwu_get_mdata_device(struct udevice *dev, struct udevice **mdata_dev)
> +{
> +	u32 phandle;
> +	int ret, size;
> +	struct udevice *parent;
> +	const fdt32_t *phandle_p = NULL;
> +
> +	phandle_p = dev_read_prop(dev, "fwu-mdata-store", &size);
> +	if (!phandle_p) {
> +		log_debug("fwu-mdata-store property not found\n");
> +		return -ENOENT;
> +	}
> +
> +	phandle = fdt32_to_cpu(*phandle_p);
> +
> +	ret = device_get_global_by_ofnode(ofnode_get_by_phandle(phandle),
> +					  &parent);
> +	if (ret)
> +		return ret;
> +
> +	return blk_get_from_parent(parent, mdata_dev);
> +}
> +
> +static int fwu_mdata_gpt_blk_probe(struct udevice *dev)
> +{
> +	int ret;
> +	struct udevice *mdata_dev = NULL;
> +	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> +
> +	ret = fwu_get_mdata_device(dev, &mdata_dev);
> +	if (ret)
> +		return ret;
> +
> +	priv->blk_dev = mdata_dev;
> +
> +	return 0;
> +}
> +
> +static const struct fwu_mdata_ops fwu_gpt_blk_ops = {
> +	.get_mdata = fwu_gpt_get_mdata,
> +	.update_mdata = fwu_gpt_update_mdata,
> +	.get_mdata_part_num = fwu_gpt_get_mdata_partitions,
> +	.read_mdata_partition = fwu_gpt_read_mdata_partition,
> +	.write_mdata_partition = fwu_gpt_write_mdata_partition,
> +};
> +
> +static const struct udevice_id fwu_mdata_ids[] = {
> +	{ .compatible = "u-boot,fwu-mdata-gpt" },
> +	{ }
> +};
> +
> +U_BOOT_DRIVER(fwu_mdata_gpt_blk) = {
> +	.name		= "fwu-mdata-gpt-blk",
> +	.id		= UCLASS_FWU_MDATA,
> +	.of_match	= fwu_mdata_ids,
> +	.ops		= &fwu_gpt_blk_ops,
> +	.probe		= fwu_mdata_gpt_blk_probe,
> +	.priv_auto	= sizeof(struct fwu_mdata_gpt_blk_priv),
> +};
> diff --git a/include/fwu.h b/include/fwu.h
> index a83ea19534..ce99c02618 100644
> --- a/include/fwu.h
> +++ b/include/fwu.h
> @@ -14,6 +14,10 @@
>  struct fwu_mdata;
>  struct udevice;
>  
> +struct fwu_mdata_gpt_blk_priv {
> +	struct udevice *blk_dev;
> +};
> +
>  /**
>   * @mdata_check: check the validity of the FWU metadata partitions
>   * @get_mdata() - Get a FWU metadata copy
> -- 
> 2.34.1
> 

Regards
/Ilias
Sughosh Ganu Oct. 21, 2022, 4:27 p.m. UTC | #2 
hi Ilias,

On Fri, 21 Oct 2022 at 20:33, Ilias Apalodimas
<ilias.apalodimas@linaro.org> wrote:
>
> Hi Sughosh
>
> > +{
> > +     int ret;
> > +     u32 len, blk_start, blkcnt;
> > +     struct disk_partition info;
> > +
> > +     ALLOC_CACHE_ALIGN_BUFFER_PAD(struct fwu_mdata, mdata_aligned, 1,
> > +                                  desc->blksz);
> > +
> > +     if (!mdata)
> > +             return -ENOMEM;
>
> ENOMEM is usually for allocation failures this is an -EINVAL
>
> > +
> > +     ret = gpt_get_mdata_disk_part(desc, &info, part_num);
> > +     if (ret < 0) {
> > +             printf("Unable to get the FWU metadata partition\n");
> > +             return -ENOENT;
> > +     }
> > +
> > +     len = sizeof(*mdata);
> > +     blkcnt = BLOCK_CNT(len, desc);
> > +     if (blkcnt > info.size) {
> > +             log_debug("Block count exceeds FWU metadata partition size\n");
> > +             return -ERANGE;
> > +     }
> > +
> > +     blk_start = info.start;
> > +     if (access == MDATA_READ) {
> > +             if (blk_dread(desc, blk_start, blkcnt, mdata_aligned) != blkcnt) {
> > +                     log_debug("Error reading FWU metadata from the device\n");
> > +                     return -EIO;
> > +             }
> > +             memcpy(mdata, mdata_aligned, sizeof(struct fwu_mdata));
> > +     } else {
>
> else if ?
>
> > +             if (blk_dwrite(desc, blk_start, blkcnt, mdata) != blkcnt) {
> > +                     log_debug("Error writing FWU metadata to the device\n");
> > +                     return -EIO;
> > +             }
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int fwu_gpt_update_mdata(struct udevice *dev, struct fwu_mdata *mdata)
> > +{
> > +     int ret;
> > +     struct blk_desc *desc;
> > +     uint mdata_parts[2];
> > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > +
> > +     desc = dev_get_uclass_plat(priv->blk_dev);
>
> dev_get_uclass_plat might return NULL,  gpt_read_write_mdata() doesn't check
> against NULL and then it ends up calling gpt_get_mdata_disk_part() which
> then calls part_get_info().  I don't think anyone checks for the desc ptr
>
> And I think this is a problem  overall in all the callbacks belowe that
> invoke dev_get_uclass_plat()

dev_get_uclass_plat() returns NULL only when the dev parameter passed
to the function is NULL. And that won't happen since that would mean
that the mdata_dev is NULL, and in such a scenario the driver's probe
function would fail. So these functions would not get called with desc
being NULL.

-sughosh

>
> > +
> > +     ret = gpt_get_mdata_partitions(desc, mdata_parts);
> > +     if (ret < 0) {
> > +             log_debug("Error getting the FWU metadata partitions\n");
> > +             return -ENOENT;
> > +     }
> > +
> > +     /* First write the primary partition */
> > +     ret = gpt_read_write_mdata(desc, mdata, MDATA_WRITE, mdata_parts[0]);
> > +     if (ret < 0) {
> > +             log_debug("Updating primary FWU metadata partition failed\n");
> > +             return ret;
> > +     }
> > +
> > +     /* And now the replica */
> > +     ret = gpt_read_write_mdata(desc, mdata, MDATA_WRITE, mdata_parts[1]);
> > +     if (ret < 0) {
> > +             log_debug("Updating secondary FWU metadata partition failed\n");
> > +             return ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int gpt_get_mdata(struct blk_desc *desc, struct fwu_mdata *mdata)
> > +{
> > +     int ret;
> > +     uint mdata_parts[2];
> > +
> > +     ret = gpt_get_mdata_partitions(desc, mdata_parts);
> > +
> > +     if (ret < 0) {
> > +             log_debug("Error getting the FWU metadata partitions\n");
> > +             return -ENOENT;
> > +     }
> > +
> > +     ret = gpt_read_write_mdata(desc, mdata, MDATA_READ, mdata_parts[0]);
> > +     if (ret < 0) {
> > +             log_debug("Failed to read the FWU metadata from the device\n");
> > +             return -EIO;
> > +     }
> > +
> > +     ret = fwu_verify_mdata(mdata, 1);
> > +     if (!ret)
> > +             return 0;
> > +
> > +     /*
> > +      * Verification of the primary FWU metadata copy failed.
> > +      * Try to read the replica.
> > +      */
> > +     memset(mdata, '\0', sizeof(struct fwu_mdata));
> > +     ret = gpt_read_write_mdata(desc, mdata, MDATA_READ, mdata_parts[1]);
> > +     if (ret < 0) {
> > +             log_debug("Failed to read the FWU metadata from the device\n");
> > +             return -EIO;
> > +     }
> > +
> > +     ret = fwu_verify_mdata(mdata, 0);
> > +     if (!ret)
> > +             return 0;
> > +
> > +     /* Both the FWU metadata copies are corrupted. */
> > +     return -EIO;
> > +}
> > +
> > +static int fwu_gpt_get_mdata(struct udevice *dev, struct fwu_mdata *mdata)
> > +{
> > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > +
> > +     return gpt_get_mdata(dev_get_uclass_plat(priv->blk_dev), mdata);
> > +}
> > +
> > +static int fwu_gpt_get_mdata_partitions(struct udevice *dev, uint *mdata_parts)
> > +{
> > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > +
> > +     return gpt_get_mdata_partitions(dev_get_uclass_plat(priv->blk_dev),
> > +                                     mdata_parts);
> > +}
> > +
> > +static int fwu_gpt_read_mdata_partition(struct udevice *dev,
> > +                                     struct fwu_mdata *mdata, uint part_num)
> > +{
> > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > +
> > +     return gpt_read_write_mdata(dev_get_uclass_plat(priv->blk_dev),
> > +                                 mdata, MDATA_READ, part_num);
> > +}
> > +
> > +static int fwu_gpt_write_mdata_partition(struct udevice *dev,
> > +                                     struct fwu_mdata *mdata, uint part_num)
> > +{
> > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > +
> > +     return gpt_read_write_mdata(dev_get_uclass_plat(priv->blk_dev),
> > +                                 mdata, MDATA_WRITE, part_num);
> > +}
> > +
> > +static int fwu_get_mdata_device(struct udevice *dev, struct udevice **mdata_dev)
> > +{
> > +     u32 phandle;
> > +     int ret, size;
> > +     struct udevice *parent;
> > +     const fdt32_t *phandle_p = NULL;
> > +
> > +     phandle_p = dev_read_prop(dev, "fwu-mdata-store", &size);
> > +     if (!phandle_p) {
> > +             log_debug("fwu-mdata-store property not found\n");
> > +             return -ENOENT;
> > +     }
> > +
> > +     phandle = fdt32_to_cpu(*phandle_p);
> > +
> > +     ret = device_get_global_by_ofnode(ofnode_get_by_phandle(phandle),
> > +                                       &parent);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return blk_get_from_parent(parent, mdata_dev);
> > +}
> > +
> > +static int fwu_mdata_gpt_blk_probe(struct udevice *dev)
> > +{
> > +     int ret;
> > +     struct udevice *mdata_dev = NULL;
> > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > +
> > +     ret = fwu_get_mdata_device(dev, &mdata_dev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     priv->blk_dev = mdata_dev;
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct fwu_mdata_ops fwu_gpt_blk_ops = {
> > +     .get_mdata = fwu_gpt_get_mdata,
> > +     .update_mdata = fwu_gpt_update_mdata,
> > +     .get_mdata_part_num = fwu_gpt_get_mdata_partitions,
> > +     .read_mdata_partition = fwu_gpt_read_mdata_partition,
> > +     .write_mdata_partition = fwu_gpt_write_mdata_partition,
> > +};
> > +
> > +static const struct udevice_id fwu_mdata_ids[] = {
> > +     { .compatible = "u-boot,fwu-mdata-gpt" },
> > +     { }
> > +};
> > +
> > +U_BOOT_DRIVER(fwu_mdata_gpt_blk) = {
> > +     .name           = "fwu-mdata-gpt-blk",
> > +     .id             = UCLASS_FWU_MDATA,
> > +     .of_match       = fwu_mdata_ids,
> > +     .ops            = &fwu_gpt_blk_ops,
> > +     .probe          = fwu_mdata_gpt_blk_probe,
> > +     .priv_auto      = sizeof(struct fwu_mdata_gpt_blk_priv),
> > +};
> > diff --git a/include/fwu.h b/include/fwu.h
> > index a83ea19534..ce99c02618 100644
> > --- a/include/fwu.h
> > +++ b/include/fwu.h
> > @@ -14,6 +14,10 @@
> >  struct fwu_mdata;
> >  struct udevice;
> >
> > +struct fwu_mdata_gpt_blk_priv {
> > +     struct udevice *blk_dev;
> > +};
> > +
> >  /**
> >   * @mdata_check: check the validity of the FWU metadata partitions
> >   * @get_mdata() - Get a FWU metadata copy
> > --
> > 2.34.1
> >
>
> Regards
> /Ilias
Ilias Apalodimas Oct. 21, 2022, 4:38 p.m. UTC | #3 
On Fri, Oct 21, 2022 at 09:57:45PM +0530, Sughosh Ganu wrote:
> hi Ilias,
> 
> On Fri, 21 Oct 2022 at 20:33, Ilias Apalodimas
> <ilias.apalodimas@linaro.org> wrote:
> >
> > Hi Sughosh
> >
> > > +{
> > > +     int ret;
> > > +     u32 len, blk_start, blkcnt;
> > > +     struct disk_partition info;
> > > +
> > > +     ALLOC_CACHE_ALIGN_BUFFER_PAD(struct fwu_mdata, mdata_aligned, 1,
> > > +                                  desc->blksz);
> > > +
> > > +     if (!mdata)
> > > +             return -ENOMEM;
> >
> > ENOMEM is usually for allocation failures this is an -EINVAL
> >
> > > +
> > > +     ret = gpt_get_mdata_disk_part(desc, &info, part_num);
> > > +     if (ret < 0) {
> > > +             printf("Unable to get the FWU metadata partition\n");
> > > +             return -ENOENT;
> > > +     }
> > > +
> > > +     len = sizeof(*mdata);
> > > +     blkcnt = BLOCK_CNT(len, desc);
> > > +     if (blkcnt > info.size) {
> > > +             log_debug("Block count exceeds FWU metadata partition size\n");
> > > +             return -ERANGE;
> > > +     }
> > > +
> > > +     blk_start = info.start;
> > > +     if (access == MDATA_READ) {
> > > +             if (blk_dread(desc, blk_start, blkcnt, mdata_aligned) != blkcnt) {
> > > +                     log_debug("Error reading FWU metadata from the device\n");
> > > +                     return -EIO;
> > > +             }
> > > +             memcpy(mdata, mdata_aligned, sizeof(struct fwu_mdata));
> > > +     } else {
> >
> > else if ?
> >
> > > +             if (blk_dwrite(desc, blk_start, blkcnt, mdata) != blkcnt) {
> > > +                     log_debug("Error writing FWU metadata to the device\n");
> > > +                     return -EIO;
> > > +             }
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int fwu_gpt_update_mdata(struct udevice *dev, struct fwu_mdata *mdata)
> > > +{
> > > +     int ret;
> > > +     struct blk_desc *desc;
> > > +     uint mdata_parts[2];
> > > +     struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
> > > +
> > > +     desc = dev_get_uclass_plat(priv->blk_dev);
> >
> > dev_get_uclass_plat might return NULL,  gpt_read_write_mdata() doesn't check
> > against NULL and then it ends up calling gpt_get_mdata_disk_part() which
> > then calls part_get_info().  I don't think anyone checks for the desc ptr
> >
> > And I think this is a problem  overall in all the callbacks belowe that
> > invoke dev_get_uclass_plat()
> 
> dev_get_uclass_plat() returns NULL only when the dev parameter passed
> to the function is NULL. And that won't happen since that would mean
> that the mdata_dev is NULL, and in such a scenario the driver's probe
> function would fail. So these functions would not get called with desc
> being NULL.
> 
> -sughosh

Ok makes sense.

Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Thanks
/Ilias


> 
> >
[...]
diff mbox series

Patch

diff --git a/drivers/fwu-mdata/Kconfig b/drivers/fwu-mdata/Kconfig
new file mode 100644
index 0000000000..36c4479a59
--- /dev/null
+++ b/drivers/fwu-mdata/Kconfig
@@ -0,0 +1,16 @@ 
+config FWU_MDATA
+	bool "Driver support for accessing FWU Metadata"
+	depends on DM
+	help
+	  Enable support for accessing FWU Metadata partitions. The
+	  FWU Metadata partitions reside on the same storage device
+	  which contains the other FWU updatable firmware images.
+
+config FWU_MDATA_GPT_BLK
+	bool "FWU Metadata access for GPT partitioned Block devices"
+	select PARTITION_TYPE_GUID
+	select PARTITION_UUIDS
+	depends on FWU_MDATA && BLK && EFI_PARTITION
+	help
+	  Enable support for accessing FWU Metadata on GPT partitioned
+	  block devices.
diff --git a/drivers/fwu-mdata/Makefile b/drivers/fwu-mdata/Makefile
new file mode 100644
index 0000000000..3fee64c10c
--- /dev/null
+++ b/drivers/fwu-mdata/Makefile
@@ -0,0 +1,8 @@ 
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright (c) 2022, Linaro Limited
+#
+
+
+obj-$(CONFIG_FWU_MDATA) += fwu-mdata-uclass.o
+obj-$(CONFIG_FWU_MDATA_GPT_BLK) += gpt_blk.o
diff --git a/drivers/fwu-mdata/gpt_blk.c b/drivers/fwu-mdata/gpt_blk.c
new file mode 100644
index 0000000000..d35ce49c5c
--- /dev/null
+++ b/drivers/fwu-mdata/gpt_blk.c
@@ -0,0 +1,290 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#define LOG_CATEGORY UCLASS_FWU_MDATA
+
+#include <blk.h>
+#include <dm.h>
+#include <efi_loader.h>
+#include <fwu.h>
+#include <fwu_mdata.h>
+#include <log.h>
+#include <memalign.h>
+#include <part.h>
+#include <part_efi.h>
+
+#include <dm/device-internal.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+
+enum {
+	MDATA_READ = 1,
+	MDATA_WRITE,
+};
+
+static int gpt_get_mdata_partitions(struct blk_desc *desc,
+				    uint mdata_parts[2])
+{
+	int i, ret;
+	u32 nparts;
+	efi_guid_t part_type_guid;
+	struct disk_partition info;
+	const efi_guid_t fwu_mdata_guid = FWU_MDATA_GUID;
+
+	nparts = 0;
+	for (i = 1; i < MAX_SEARCH_PARTITIONS; i++) {
+		if (part_get_info(desc, i, &info))
+			continue;
+		uuid_str_to_bin(info.type_guid, part_type_guid.b,
+				UUID_STR_FORMAT_GUID);
+
+		if (!guidcmp(&fwu_mdata_guid, &part_type_guid)) {
+			if (nparts < 2)
+				mdata_parts[nparts] = i;
+			++nparts;
+		}
+	}
+
+	if (nparts != 2) {
+		log_debug("Expect two copies of the FWU metadata instead of %d\n",
+			  nparts);
+		ret = -EINVAL;
+	} else {
+		ret = 0;
+	}
+
+	return ret;
+}
+
+static int gpt_get_mdata_disk_part(struct blk_desc *desc,
+				   struct disk_partition *info,
+				   u32 part_num)
+{
+	int ret;
+	char *mdata_guid_str = "8a7a84a0-8387-40f6-ab41-a8b9a5a60d23";
+
+	ret = part_get_info(desc, part_num, info);
+	if (ret < 0) {
+		log_debug("Unable to get the partition info for the FWU metadata part %d\n",
+			  part_num);
+		return -ENOENT;
+	}
+
+	/* Check that it is indeed the FWU metadata partition */
+	if (!strncmp(info->type_guid, mdata_guid_str, UUID_STR_LEN))
+		return 0;
+
+	return -ENOENT;
+}
+
+static int gpt_read_write_mdata(struct blk_desc *desc,
+				struct fwu_mdata *mdata,
+				u8 access, u32 part_num)
+{
+	int ret;
+	u32 len, blk_start, blkcnt;
+	struct disk_partition info;
+
+	ALLOC_CACHE_ALIGN_BUFFER_PAD(struct fwu_mdata, mdata_aligned, 1,
+				     desc->blksz);
+
+	if (!mdata)
+		return -ENOMEM;
+
+	ret = gpt_get_mdata_disk_part(desc, &info, part_num);
+	if (ret < 0) {
+		printf("Unable to get the FWU metadata partition\n");
+		return -ENOENT;
+	}
+
+	len = sizeof(*mdata);
+	blkcnt = BLOCK_CNT(len, desc);
+	if (blkcnt > info.size) {
+		log_debug("Block count exceeds FWU metadata partition size\n");
+		return -ERANGE;
+	}
+
+	blk_start = info.start;
+	if (access == MDATA_READ) {
+		if (blk_dread(desc, blk_start, blkcnt, mdata_aligned) != blkcnt) {
+			log_debug("Error reading FWU metadata from the device\n");
+			return -EIO;
+		}
+		memcpy(mdata, mdata_aligned, sizeof(struct fwu_mdata));
+	} else {
+		if (blk_dwrite(desc, blk_start, blkcnt, mdata) != blkcnt) {
+			log_debug("Error writing FWU metadata to the device\n");
+			return -EIO;
+		}
+	}
+
+	return 0;
+}
+
+static int fwu_gpt_update_mdata(struct udevice *dev, struct fwu_mdata *mdata)
+{
+	int ret;
+	struct blk_desc *desc;
+	uint mdata_parts[2];
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	desc = dev_get_uclass_plat(priv->blk_dev);
+
+	ret = gpt_get_mdata_partitions(desc, mdata_parts);
+	if (ret < 0) {
+		log_debug("Error getting the FWU metadata partitions\n");
+		return -ENOENT;
+	}
+
+	/* First write the primary partition */
+	ret = gpt_read_write_mdata(desc, mdata, MDATA_WRITE, mdata_parts[0]);
+	if (ret < 0) {
+		log_debug("Updating primary FWU metadata partition failed\n");
+		return ret;
+	}
+
+	/* And now the replica */
+	ret = gpt_read_write_mdata(desc, mdata, MDATA_WRITE, mdata_parts[1]);
+	if (ret < 0) {
+		log_debug("Updating secondary FWU metadata partition failed\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int gpt_get_mdata(struct blk_desc *desc, struct fwu_mdata *mdata)
+{
+	int ret;
+	uint mdata_parts[2];
+
+	ret = gpt_get_mdata_partitions(desc, mdata_parts);
+
+	if (ret < 0) {
+		log_debug("Error getting the FWU metadata partitions\n");
+		return -ENOENT;
+	}
+
+	ret = gpt_read_write_mdata(desc, mdata, MDATA_READ, mdata_parts[0]);
+	if (ret < 0) {
+		log_debug("Failed to read the FWU metadata from the device\n");
+		return -EIO;
+	}
+
+	ret = fwu_verify_mdata(mdata, 1);
+	if (!ret)
+		return 0;
+
+	/*
+	 * Verification of the primary FWU metadata copy failed.
+	 * Try to read the replica.
+	 */
+	memset(mdata, '\0', sizeof(struct fwu_mdata));
+	ret = gpt_read_write_mdata(desc, mdata, MDATA_READ, mdata_parts[1]);
+	if (ret < 0) {
+		log_debug("Failed to read the FWU metadata from the device\n");
+		return -EIO;
+	}
+
+	ret = fwu_verify_mdata(mdata, 0);
+	if (!ret)
+		return 0;
+
+	/* Both the FWU metadata copies are corrupted. */
+	return -EIO;
+}
+
+static int fwu_gpt_get_mdata(struct udevice *dev, struct fwu_mdata *mdata)
+{
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	return gpt_get_mdata(dev_get_uclass_plat(priv->blk_dev), mdata);
+}
+
+static int fwu_gpt_get_mdata_partitions(struct udevice *dev, uint *mdata_parts)
+{
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	return gpt_get_mdata_partitions(dev_get_uclass_plat(priv->blk_dev),
+					mdata_parts);
+}
+
+static int fwu_gpt_read_mdata_partition(struct udevice *dev,
+					struct fwu_mdata *mdata, uint part_num)
+{
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	return gpt_read_write_mdata(dev_get_uclass_plat(priv->blk_dev),
+				    mdata, MDATA_READ, part_num);
+}
+
+static int fwu_gpt_write_mdata_partition(struct udevice *dev,
+					struct fwu_mdata *mdata, uint part_num)
+{
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	return gpt_read_write_mdata(dev_get_uclass_plat(priv->blk_dev),
+				    mdata, MDATA_WRITE, part_num);
+}
+
+static int fwu_get_mdata_device(struct udevice *dev, struct udevice **mdata_dev)
+{
+	u32 phandle;
+	int ret, size;
+	struct udevice *parent;
+	const fdt32_t *phandle_p = NULL;
+
+	phandle_p = dev_read_prop(dev, "fwu-mdata-store", &size);
+	if (!phandle_p) {
+		log_debug("fwu-mdata-store property not found\n");
+		return -ENOENT;
+	}
+
+	phandle = fdt32_to_cpu(*phandle_p);
+
+	ret = device_get_global_by_ofnode(ofnode_get_by_phandle(phandle),
+					  &parent);
+	if (ret)
+		return ret;
+
+	return blk_get_from_parent(parent, mdata_dev);
+}
+
+static int fwu_mdata_gpt_blk_probe(struct udevice *dev)
+{
+	int ret;
+	struct udevice *mdata_dev = NULL;
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	ret = fwu_get_mdata_device(dev, &mdata_dev);
+	if (ret)
+		return ret;
+
+	priv->blk_dev = mdata_dev;
+
+	return 0;
+}
+
+static const struct fwu_mdata_ops fwu_gpt_blk_ops = {
+	.get_mdata = fwu_gpt_get_mdata,
+	.update_mdata = fwu_gpt_update_mdata,
+	.get_mdata_part_num = fwu_gpt_get_mdata_partitions,
+	.read_mdata_partition = fwu_gpt_read_mdata_partition,
+	.write_mdata_partition = fwu_gpt_write_mdata_partition,
+};
+
+static const struct udevice_id fwu_mdata_ids[] = {
+	{ .compatible = "u-boot,fwu-mdata-gpt" },
+	{ }
+};
+
+U_BOOT_DRIVER(fwu_mdata_gpt_blk) = {
+	.name		= "fwu-mdata-gpt-blk",
+	.id		= UCLASS_FWU_MDATA,
+	.of_match	= fwu_mdata_ids,
+	.ops		= &fwu_gpt_blk_ops,
+	.probe		= fwu_mdata_gpt_blk_probe,
+	.priv_auto	= sizeof(struct fwu_mdata_gpt_blk_priv),
+};
diff --git a/include/fwu.h b/include/fwu.h
index a83ea19534..ce99c02618 100644
--- a/include/fwu.h
+++ b/include/fwu.h
@@ -14,6 +14,10 @@ 
 struct fwu_mdata;
 struct udevice;
 
+struct fwu_mdata_gpt_blk_priv {
+	struct udevice *blk_dev;
+};
+
 /**
  * @mdata_check: check the validity of the FWU metadata partitions
  * @get_mdata() - Get a FWU metadata copy