Re: [PATCH v5 03/23] FWU: Add FWU metadata access driver for GPT partitioned block devices

Patrick DELAUNAY
2022-06-21T09:34:22Z

Hi,

On 6/9/22 14:29, Sughosh Ganu wrote:
> 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 formated with GPT based partition scheme.
>
> Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
> ---
> drivers/fwu-mdata/Kconfig | 9 +
> drivers/fwu-mdata/Makefile | 1 +
> drivers/fwu-mdata/fwu_mdata_gpt_blk.c | 404 ++++++++++++++++++++++++++
> include/fwu.h | 2 +
> 4 files changed, 416 insertions(+)
> create mode 100644 drivers/fwu-mdata/fwu_mdata_gpt_blk.c
>
> diff --git a/drivers/fwu-mdata/Kconfig b/drivers/fwu-mdata/Kconfig
> index d6a21c8e19..d5edef19d6 100644
> --- a/drivers/fwu-mdata/Kconfig
> +++ b/drivers/fwu-mdata/Kconfig
> @@ -5,3 +5,12 @@ config DM_FWU_MDATA
> 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 DM && HAVE_BLOCK_DEVICE && 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
> index 7fec7171f4..12a5b4fe04 100644
> --- a/drivers/fwu-mdata/Makefile
> +++ b/drivers/fwu-mdata/Makefile
> @@ -4,3 +4,4 @@
> #
>
> obj-$(CONFIG_DM_FWU_MDATA) += fwu-mdata-uclass.o
> +obj-$(CONFIG_FWU_MDATA_GPT_BLK) += fwu_mdata_gpt_blk.o

It is strange to have '_' and '-' in file name for the same directory

=> to be coherent = fwu-mdata-gpt-blk.c

> diff --git a/drivers/fwu-mdata/fwu_mdata_gpt_blk.c b/drivers/fwu-mdata/fwu_mdata_gpt_blk.c
> new file mode 100644
> index 0000000000..329bd3779b
> --- /dev/null
> +++ b/drivers/fwu-mdata/fwu_mdata_gpt_blk.c
> @@ -0,0 +1,404 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) 2022, Linaro Limited
> + */
> +
> +#include <blk.h>
> +#include <dm.h>
> +#include <efi_loader.h>
> +#include <fwu.h>
> +#include <fwu_mdata.h>
> +#include <log.h>
> +#include <malloc.h>
> +#include <memalign.h>
> +#include <part.h>
> +#include <part_efi.h>
> +
> +#include <dm/device-internal.h>
> +#include <linux/errno.h>
> +#include <linux/types.h>
> +#include <u-boot/crc.h>
> +
> +#define PRIMARY_PART BIT(0)
> +#define SECONDARY_PART BIT(1)
> +#define BOTH_PARTS (PRIMARY_PART | SECONDARY_PART)
> +
> +#define MDATA_READ BIT(0)
> +#define MDATA_WRITE BIT(1)
> +
> +

[...]

> +
> +int fwu_gpt_mdata_check(struct udevice *dev)
> +{
> + /*
> + * Check if both the copies of the FWU metadata are
> + * valid. If one has gone bad, restore it from the
> + * other good copy.
> + */
> + return gpt_check_mdata_validity(dev);
> +}
> +
> +int fwu_gpt_get_mdata(struct udevice *dev, struct fwu_mdata **mdata)
> +{
> + struct blk_desc *desc;
> +
> + desc = dev_get_uclass_plat(dev_get_priv(dev));

as dev = fwu_mdata_gpt_blk(UCLASS_FWU_MDATA)

dev_get_priv(dev) => get value saved in dev_set_priv(dev, mdata_dev);

even if it is OK, it not clear here.

can you add a struct to prepare addition of other elements in privdata:

struct fwu_mdata_gpt_blk_priv {
struct udevice *blk_dev;
}

+ struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);

+ struct blk_desc *desc;

+ desc = dev_get_uclass_plat(priv->blk_dev);

> + if (!desc) {
> + log_err("Block device not found\n");
> + return -ENODEV;
> + }
> +
> + return gpt_get_mdata(desc, mdata);
> +}
> +
> +int fwu_get_mdata_device(struct udevice *dev, struct udevice **mdata_dev)
> +{
> + u32 phandle;
> + int ret, size;
> + struct udevice *parent, *child;
> + const fdt32_t *phandle_p = NULL;
> +
> + phandle_p = ofnode_get_property(dev_ofnode(dev), "fwu-mdata-store",
> + &size);

phandle_p = dev_read_prop(dev, "fwu-mdata-store", &size);

it is more simple

> + if (!phandle_p) {
> + log_err("fwu-mdata-store property not found\n");
> + return -ENOENT;
> + }
> +
> + phandle = fdt32_to_cpu(*phandle_p);

or phandle can be read directly by

+ ret =dev_read_phandle_with_args(dev, "fwu-mdata-store", NULL, 0, 0,
phandle_p)

+ if (ret) {
+ log_err("fwu-mdata-store property not found\n");
+ return ret;
+ }

> +
> + ret = device_get_global_by_ofnode(ofnode_get_by_phandle(phandle),
> + &parent);
> + if (ret)
> + return ret;
> +
> + ret = -ENODEV;
> + for (device_find_first_child(parent, &child); child;
> + device_find_next_child(&child)) {
> + if (device_get_uclass_id(child) == UCLASS_BLK) {
> + *mdata_dev = child;
> + ret = 0;
> + }
> + }
> +
> + return ret;
> +}
> +
> +static int fwu_mdata_gpt_blk_probe(struct udevice *dev)
> +{
> + int ret;
> + struct udevice *mdata_dev = NULL;
> +
> + ret = fwu_get_mdata_device(dev, &mdata_dev);
> + if (ret)
> + return ret;
> +
> + dev_set_priv(dev, mdata_dev);

Avoid to use dev_set_priv() in driver :

/**
* dev_set_priv() - Set the private data for a device
*
* This is normally handled by driver model, which automatically allocates
* private data when an 'auto' size if provided by the driver.
*
* Use this function to override normal operation for special
situations, such
* as needing to allocate a variable amount of data.
*

...

+ struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);

+ priv->blk_dev = mdata_dev;

> +
> + return 0;
> +}
> +
> +static const struct fwu_mdata_ops fwu_gpt_blk_ops = {
> + .mdata_check = fwu_gpt_mdata_check,
> + .get_mdata = fwu_gpt_get_mdata,
> + .update_mdata = fwu_gpt_update_mdata,
> +};
> +
> +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 f9e44e7b39..3b1ee4e83e 100644
> --- a/include/fwu.h
> +++ b/include/fwu.h
> @@ -39,6 +39,8 @@ int fwu_get_active_index(u32 *active_idx);
> int fwu_update_active_index(u32 active_idx);
> int fwu_get_image_alt_num(efi_guid_t *image_type_id, u32 update_bank,
> int *alt_num);
> +int fwu_get_mdata_device(struct udevice *dev, struct udevice **mdata_dev);
> +int fwu_verify_mdata(struct fwu_mdata *mdata, bool pri_part);
> int fwu_mdata_check(void);
> int fwu_revert_boot_index(void);
> int fwu_accept_image(efi_guid_t *img_type_id, u32 bank);

Regards

Patrick