[PATCH v10 02/15] FWU: Add FWU metadata structure and driver for accessing metadata

[Sughosh Ganu <sughosh.ganu@linaro.org>]

In the FWU Multi Bank Update feature, the information about the
updatable images is stored as part of the metadata, which is stored on
a dedicated partition. Add the metadata structure, and a driver model
uclass which provides functions to access the metadata. These are
generic API's, and implementations can be added based on parameters
like how the metadata partition is accessed and what type of storage
device houses the metadata.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Etienne Carriere <etienne.carriere@linaro.org>
---
Changes since V9:
* Add a helper function fwu_get_dev_mdata() to get the FWU metadata
  device and read the metadata.
* Rename fwu_get_image_alt_num() as fwu_get_image_image_index() based
  on suggestion from Takahiro.

 drivers/fwu-mdata/fwu-mdata-uclass.c | 107 +++++++++
 include/dm/uclass-id.h               |   1 +
 include/fwu.h                        | 214 +++++++++++++++++
 include/fwu_mdata.h                  |  67 ++++++
 lib/fwu_updates/fwu.c                | 333 +++++++++++++++++++++++++++
 5 files changed, 722 insertions(+)
 create mode 100644 drivers/fwu-mdata/fwu-mdata-uclass.c
 create mode 100644 include/fwu.h
 create mode 100644 include/fwu_mdata.h
 create mode 100644 lib/fwu_updates/fwu.c

diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c b/drivers/fwu-mdata/fwu-mdata-uclass.c
new file mode 100644
index 0000000000..65ae93c21f
--- /dev/null
+++ b/drivers/fwu-mdata/fwu-mdata-uclass.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#define LOG_CATEGORY UCLASS_FWU_MDATA
+
+#include <common.h>
+#include <dm.h>
+#include <efi_loader.h>
+#include <fwu.h>
+#include <fwu_mdata.h>
+#include <log.h>
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <u-boot/crc.h>
+
+/**
+ * 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 bad 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->mdata_check) {
+		log_debug("mdata_check() method not defined\n");
+		return -ENOSYS;
+	}
+
+	return ops->mdata_check(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
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_get_mdata(struct udevice *dev, struct fwu_mdata *mdata)
+{
+	const struct fwu_mdata_ops *ops = device_get_ops(dev);
+
+	if (!ops->get_mdata) {
+		log_debug("get_mdata() method not defined\n");
+		return -ENOSYS;
+	}
+
+	return ops->get_mdata(dev, mdata);
+}
+
+/**
+ * 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()
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_update_mdata(struct udevice *dev, struct fwu_mdata *mdata)
+{
+	void *buf;
+	const struct fwu_mdata_ops *ops = device_get_ops(dev);
+
+	if (!ops->update_mdata) {
+		log_debug("get_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);
+}
+
+UCLASS_DRIVER(fwu_mdata) = {
+	.id		= UCLASS_FWU_MDATA,
+	.name		= "fwu-mdata",
+};
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index a432e43871..598a8c10a0 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -58,6 +58,7 @@ enum uclass_id {
 	UCLASS_FIRMWARE,	/* Firmware */
 	UCLASS_FUZZING_ENGINE,	/* Fuzzing engine */
 	UCLASS_FS_FIRMWARE_LOADER,		/* Generic loader */
+	UCLASS_FWU_MDATA,	/* FWU Metadata Access */
 	UCLASS_GPIO,		/* Bank of general-purpose I/O pins */
 	UCLASS_HASH,		/* Hash device */
 	UCLASS_HWSPINLOCK,	/* Hardware semaphores */
diff --git a/include/fwu.h b/include/fwu.h
new file mode 100644
index 0000000000..745f6225d0
--- /dev/null
+++ b/include/fwu.h
@@ -0,0 +1,214 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#if !defined _FWU_H_
+#define _FWU_H_
+
+#include <blk.h>
+#include <efi.h>
+
+#include <linux/types.h>
+
+struct fwu_mdata;
+struct udevice;
+
+/**
+ * @mdata_check: check the validity of the FWU metadata partitions
+ * @get_mdata() - Get a FWU metadata copy
+ * @update_mdata() - Update the FWU metadata copy
+ */
+struct fwu_mdata_ops {
+	/**
+	 * mdata_check() - Check if the FWU metadata is valid
+	 * @dev:	FWU device
+	 *
+	 * Validate both copies of the FWU metadata. If one of the copies
+	 * has gone bad, restore it from the other bad copy.
+	 *
+	 * Return: 0 if OK, -ve on error
+	 */
+	int (*mdata_check)(struct udevice *dev);
+
+	/**
+	 * get_mdata() - Get a FWU metadata copy
+	 * @dev:	FWU device
+	 * @mdata:	Pointer to FWU metadata
+	 *
+	 * Get a valid copy of the FWU metadata.
+	 *
+	 * Return: 0 if OK, -ve on error
+	 */
+	int (*get_mdata)(struct udevice *dev, struct fwu_mdata *mdata);
+
+	/**
+	 * fwu_update_mdata() - Update the FWU metadata
+	 * @dev:	FWU device
+	 * @mdata:	Copy of the FWU metadata
+	 *
+	 * Update the FWU metadata structure by writing to the
+	 * FWU metadata partitions.
+	 *
+	 * Return: 0 if OK, -ve on error
+	 */
+	int (*update_mdata)(struct udevice *dev, struct fwu_mdata *mdata);
+};
+
+#define FWU_MDATA_VERSION	0x1
+
+/*
+* GUID value defined in the FWU specification for identification
+* of the FWU metadata partition.
+*/
+#define FWU_MDATA_GUID \
+	EFI_GUID(0x8a7a84a0, 0x8387, 0x40f6, 0xab, 0x41, \
+		 0xa8, 0xb9, 0xa5, 0xa6, 0x0d, 0x23)
+
+/**
+ * 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
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_get_mdata(struct udevice *dev, struct fwu_mdata *mdata);
+
+/**
+ * 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()
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_update_mdata(struct udevice *dev, struct fwu_mdata *mdata);
+
+/**
+ * fwu_get_active_index() - Get active_index from the FWU metadata
+ * @active_idxp: active_index value to be read
+ *
+ * Read the active_index field from the FWU metadata and place it in
+ * the variable pointed to be the function argument.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_get_active_index(u32 *active_idxp);
+
+/**
+ * fwu_update_active_index() - Update active_index from the FWU metadata
+ * @active_idx: active_index value to be updated
+ *
+ * Update the active_index field in the FWU metadata
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_update_active_index(uint active_idx);
+
+/**
+ * fwu_get_image_index() - Get the Image Index to be used for capsule update
+ * @image_type_id: pointer to the image GUID as passed in the capsule
+ * @update_bank: Bank to which the update is to be made
+ * @image_index: The Image Index for the image
+ *
+ * Based on the GUID value passed in the capsule, along with the bank to which the
+ * image needs to be updated, get the Image Index value which will be used for the
+ * capsule update.
+ *
+ * Currently, the capsule update driver uses the DFU framework for
+ * the updates. This function gets the DFU alt number which is to
+ * be used as the Image Index
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_get_image_index(efi_guid_t *image_type_id, u32 update_bank,
+			u8 *image_index);
+
+/**
+ * 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 bad copy.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_mdata_check(struct udevice *dev);
+
+/**
+ * fwu_revert_boot_index() - Revert the active index in the FWU metadata
+ *
+ * Revert the active_index value in the FWU metadata, by swapping the values
+ * of active_index and previous_active_index in both copies of the
+ * FWU metadata.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_revert_boot_index(void);
+
+/**
+ * fwu_verify_mdata() - Verify the FWU metadata
+ * @mdata: FWU metadata structure
+ * @pri_part: FWU metadata partition is primary or secondary
+ *
+ * Verify the FWU metadata by computing the CRC32 for the metadata
+ * structure and comparing it against the CRC32 value stored as part
+ * of the structure.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_verify_mdata(struct fwu_mdata *mdata, bool pri_part);
+
+/**
+ * fwu_accept_image() - Set the Acceptance bit for the image
+ * @img_type_id: GUID of the image type for which the accepted bit is to be
+ *               cleared
+ * @bank: Bank of which the image's Accept bit is to be set
+ *
+ * Set the accepted bit for the image specified by the img_guid parameter. This
+ * indicates acceptance of image for subsequent boots by some governing component
+ * like OS(or firmware).
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_accept_image(efi_guid_t *img_type_id, u32 bank);
+
+/**
+ * fwu_clear_accept_image() - Clear the Acceptance bit for the image
+ * @img_type_id: GUID of the image type for which the accepted bit is to be
+ *               cleared
+ * @bank: Bank of which the image's Accept bit is to be cleared
+ *
+ * Clear the accepted bit for the image type specified by the img_type_id parameter.
+ * This function is called after the image has been updated. The accepted bit is
+ * cleared to be set subsequently after passing the image acceptance criteria, by
+ * either the OS(or firmware)
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_clear_accept_image(efi_guid_t *img_type_id, u32 bank);
+
+#endif /* _FWU_H_ */
diff --git a/include/fwu_mdata.h b/include/fwu_mdata.h
new file mode 100644
index 0000000000..8fda4f4ac2
--- /dev/null
+++ b/include/fwu_mdata.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#if !defined _FWU_MDATA_H_
+#define _FWU_MDATA_H_
+
+#include <efi.h>
+
+/**
+ * struct fwu_image_bank_info - firmware image information
+ * @image_uuid: Guid value of the image in this bank
+ * @accepted: Acceptance status of the image
+ * @reserved: Reserved
+ *
+ * The structure contains image specific fields which are
+ * used to identify the image and to specify the image's
+ * acceptance status
+ */
+struct fwu_image_bank_info {
+	efi_guid_t  image_uuid;
+	uint32_t accepted;
+	uint32_t reserved;
+};
+
+/**
+ * struct fwu_image_entry - information for a particular type of image
+ * @image_type_uuid: Guid value for identifying the image type
+ * @location_uuid: Guid of the storage volume where the image is located
+ * @img_bank_info: Array containing properties of images
+ *
+ * This structure contains information on various types of updatable
+ * firmware images. Each image type then contains an array of image
+ * information per bank.
+ */
+struct fwu_image_entry {
+	efi_guid_t image_type_uuid;
+	efi_guid_t location_uuid;
+	struct fwu_image_bank_info img_bank_info[CONFIG_FWU_NUM_BANKS];
+};
+
+/**
+ * struct fwu_mdata - FWU metadata structure for multi-bank updates
+ * @crc32: crc32 value for the FWU metadata
+ * @version: FWU metadata version
+ * @active_index: Index of the bank currently used for booting images
+ * @previous_active_inde: Index of the bank used before the current bank
+ *                        being used for booting
+ * @img_entry: Array of information on various firmware images that can
+ *             be updated
+ *
+ * This structure is used to store all the needed information for performing
+ * multi bank updates on the platform. This contains info on the bank being
+ * used to boot along with the information needed for identification of
+ * individual images
+ */
+struct fwu_mdata {
+	uint32_t crc32;
+	uint32_t version;
+	uint32_t active_index;
+	uint32_t previous_active_index;
+
+	struct fwu_image_entry img_entry[CONFIG_FWU_NUM_IMAGES_PER_BANK];
+};
+
+#endif /* _FWU_MDATA_H_ */
diff --git a/lib/fwu_updates/fwu.c b/lib/fwu_updates/fwu.c
new file mode 100644
index 0000000000..fb9dbca307
--- /dev/null
+++ b/lib/fwu_updates/fwu.c
@@ -0,0 +1,333 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#include <dm.h>
+#include <efi_loader.h>
+#include <fwu.h>
+#include <fwu_mdata.h>
+#include <log.h>
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <u-boot/crc.h>
+
+#define IMAGE_ACCEPT_SET	BIT(0)
+#define IMAGE_ACCEPT_CLEAR	BIT(1)
+
+static int fwu_get_dev_mdata(struct udevice **dev, struct fwu_mdata *mdata)
+
+{
+	int ret;
+
+	ret = uclass_first_device(UCLASS_FWU_MDATA, dev);
+	if (ret) {
+		log_debug("Cannot find fwu device\n");
+		return ret;
+	}
+
+	ret = fwu_get_mdata(*dev, mdata);
+	if (ret < 0)
+		log_debug("Unable to get valid FWU metadata\n");
+
+	return ret;
+}
+
+/**
+ * fwu_verify_mdata() - Verify the FWU metadata
+ * @mdata: FWU metadata structure
+ * @pri_part: FWU metadata partition is primary or secondary
+ *
+ * Verify the FWU metadata by computing the CRC32 for the metadata
+ * structure and comparing it against the CRC32 value stored as part
+ * of the structure.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_verify_mdata(struct fwu_mdata *mdata, bool pri_part)
+{
+	u32 calc_crc32;
+	void *buf;
+
+	buf = &mdata->version;
+	calc_crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32));
+
+	if (calc_crc32 != mdata->crc32) {
+		log_debug("crc32 check failed for %s FWU metadata partition\n",
+			  pri_part ? "primary" : "secondary");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * fwu_get_active_index() - Get active_index from the FWU metadata
+ * @active_idx: active_index value to be read
+ *
+ * Read the active_index field from the FWU metadata and place it in
+ * the variable pointed to be the function argument.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_get_active_index(u32 *active_idx)
+{
+	int ret;
+	struct udevice *dev;
+	struct fwu_mdata mdata = { 0 };
+
+	ret = fwu_get_dev_mdata(&dev, &mdata);
+	if (ret)
+		return ret;
+
+	/*
+	 * Found the FWU metadata partition, now read the active_index
+	 * value
+	 */
+	*active_idx = mdata.active_index;
+	if (*active_idx >= CONFIG_FWU_NUM_BANKS) {
+		log_debug("Active index value read is incorrect\n");
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+/**
+ * fwu_update_active_index() - Update active_index from the FWU metadata
+ * @active_idx: active_index value to be updated
+ *
+ * Update the active_index field in the FWU metadata
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_update_active_index(uint active_idx)
+{
+	int ret;
+	struct udevice *dev;
+	struct fwu_mdata mdata = { 0 };
+
+	if (active_idx >= CONFIG_FWU_NUM_BANKS) {
+		log_debug("Invalid active index value\n");
+		return -EINVAL;
+	}
+
+	ret = fwu_get_dev_mdata(&dev, &mdata);
+	if (ret)
+		return ret;
+
+	/*
+	 * Update the active index and previous_active_index fields
+	 * in the FWU metadata
+	 */
+	mdata.previous_active_index = mdata.active_index;
+	mdata.active_index = active_idx;
+
+	/*
+	 * Now write this updated FWU metadata to both the
+	 * FWU metadata partitions
+	 */
+	ret = fwu_update_mdata(dev, &mdata);
+	if (ret < 0) {
+		log_debug("Failed to update FWU metadata partitions\n");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+/**
+ * fwu_get_image_index() - Get the Image Index to be used for capsule update
+ * @image_type_id: pointer to the image GUID as passed in the capsule
+ * @update_bank: Bank to which the update is to be made
+ * @image_index: The Image Index for the image
+ *
+ * Based on the GUID value passed in the capsule, along with the bank to which the
+ * image needs to be updated, get the Image Index value which will be used for the
+ * capsule update.
+ *
+ * Currently, the capsule update driver uses the DFU framework for
+ * the updates. This function gets the DFU alt number which is to
+ * be used as the Image Index
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_get_image_index(efi_guid_t *image_type_id, u32 update_bank,
+			u8 *image_index)
+{
+	int ret, i;
+	efi_guid_t *image_guid;
+	struct udevice *dev;
+	struct fwu_mdata mdata = { 0 };
+	struct fwu_image_entry *img_entry;
+	struct fwu_image_bank_info *img_bank_info;
+
+	ret = fwu_get_dev_mdata(&dev, &mdata);
+	if (ret)
+		return ret;
+
+	ret = -EINVAL;
+	/*
+	 * The FWU metadata has been read. Now get the image_uuid for the
+	 * image with the update_bank.
+	 */
+	for (i = 0; i < CONFIG_FWU_NUM_IMAGES_PER_BANK; i++) {
+		if (!guidcmp(image_type_id,
+			     &mdata.img_entry[i].image_type_uuid)) {
+			img_entry = &mdata.img_entry[i];
+			img_bank_info = &img_entry->img_bank_info[update_bank];
+			image_guid = &img_bank_info->image_uuid;
+			ret = fwu_plat_get_alt_num(dev, image_guid, image_index);
+			if (ret) {
+				log_debug("alt_num not found for partition with GUID %pUs\n",
+					  image_guid);
+			} else {
+				log_debug("alt_num %d for partition %pUs\n",
+					  *image_index, image_guid);
+				++*image_index;
+			}
+
+			goto out;
+		}
+	}
+
+	log_debug("Partition with the image type %pUs not found\n",
+		  image_type_id);
+
+out:
+	return ret;
+}
+
+/**
+ * fwu_revert_boot_index() - Revert the active index in the FWU metadata
+ *
+ * Revert the active_index value in the FWU metadata, by swapping the values
+ * of active_index and previous_active_index in both copies of the
+ * FWU metadata.
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_revert_boot_index(void)
+{
+	int ret;
+	u32 cur_active_index;
+	struct udevice *dev;
+	struct fwu_mdata mdata = { 0 };
+
+	ret = fwu_get_dev_mdata(&dev, &mdata);
+	if (ret)
+		return ret;
+
+	/*
+	 * Swap the active index and previous_active_index fields
+	 * in the FWU metadata
+	 */
+	cur_active_index = mdata.active_index;
+	mdata.active_index = mdata.previous_active_index;
+	mdata.previous_active_index = cur_active_index;
+
+	/*
+	 * Now write this updated FWU metadata to both the
+	 * FWU metadata partitions
+	 */
+	ret = fwu_update_mdata(dev, &mdata);
+	if (ret < 0) {
+		log_debug("Failed to update FWU metadata partitions\n");
+		ret = -EIO;
+	}
+
+	return ret;
+}
+
+/**
+ * fwu_clrset_image_accept() - Set or Clear the Acceptance bit for the image
+ * @img_type_id: GUID of the image type for which the accepted bit is to be
+ *               set or cleared
+ * @bank: Bank of which the image's Accept bit is to be set or cleared
+ * @action: Action which specifies whether image's Accept bit is to be set or
+ *          cleared
+ *
+ * Set/Clear the accepted bit for the image specified by the img_guid parameter.
+ * This indicates acceptance or rejection of image for subsequent boots by some
+ * governing component like OS(or firmware).
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+static int fwu_clrset_image_accept(efi_guid_t *img_type_id, u32 bank, u8 action)
+{
+	int ret, i;
+	struct udevice *dev;
+	struct fwu_mdata mdata = { 0 };
+	struct fwu_image_entry *img_entry;
+	struct fwu_image_bank_info *img_bank_info;
+
+	ret = fwu_get_dev_mdata(&dev, &mdata);
+	if (ret)
+		return ret;
+
+	img_entry = &mdata.img_entry[0];
+	for (i = 0; i < CONFIG_FWU_NUM_IMAGES_PER_BANK; i++) {
+		if (!guidcmp(&img_entry[i].image_type_uuid, img_type_id)) {
+			img_bank_info = &img_entry[i].img_bank_info[bank];
+			if (action == IMAGE_ACCEPT_SET)
+				img_bank_info->accepted |= FWU_IMAGE_ACCEPTED;
+			else
+				img_bank_info->accepted = 0;
+
+			ret = fwu_update_mdata(dev, &mdata);
+			goto out;
+		}
+	}
+
+	/* Image not found */
+	ret = -ENOENT;
+
+out:
+	return ret;
+}
+
+/**
+ * fwu_accept_image() - Set the Acceptance bit for the image
+ * @img_type_id: GUID of the image type for which the accepted bit is to be
+ *               cleared
+ * @bank: Bank of which the image's Accept bit is to be set
+ *
+ * Set the accepted bit for the image specified by the img_guid parameter. This
+ * indicates acceptance of image for subsequent boots by some governing component
+ * like OS(or firmware).
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_accept_image(efi_guid_t *img_type_id, u32 bank)
+{
+	return fwu_clrset_image_accept(img_type_id, bank,
+				       IMAGE_ACCEPT_SET);
+}
+
+/**
+ * fwu_clear_accept_image() - Clear the Acceptance bit for the image
+ * @img_type_id: GUID of the image type for which the accepted bit is to be
+ *               cleared
+ * @bank: Bank of which the image's Accept bit is to be cleared
+ *
+ * Clear the accepted bit for the image type specified by the img_type_id parameter.
+ * This function is called after the image has been updated. The accepted bit is
+ * cleared to be set subsequently after passing the image acceptance criteria, by
+ * either the OS(or firmware)
+ *
+ * Return: 0 if OK, -ve on error
+ *
+ */
+int fwu_clear_accept_image(efi_guid_t *img_type_id, u32 bank)
+{
+	return fwu_clrset_image_accept(img_type_id, bank,
+				       IMAGE_ACCEPT_CLEAR);
+}
-- 
2.34.1