[PATCH v8 06/13] FWU: Add helper functions for accessing FWU metadata

[Sughosh Ganu]

Add weak functions for getting the update index value and dfu
alternate number needed for FWU Multi Bank update
functionality.

The current implementation for getting the update index value is for
platforms with 2 banks. If a platform supports more than 2 banks, it
can implement it's own function. The function to get the dfu alternate
number has been added for platforms with GPT partitioned storage
devices. Platforms with other storage partition scheme need to
implement their own function.

Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
Reviewed-by: Patrick Delaunay <patrick.delaunay at foss.st.com>
---
Changes since V7:
* Moved the API's fwu_plat_get_update_index() and
  fwu_plat_get_alt_num() as weak functions in common code as suggested
  by Ilias.

 include/fwu.h             |   1 +
 lib/fwu_updates/Makefile  |   7 +++
 lib/fwu_updates/fwu.c     |  22 ++++++++
 lib/fwu_updates/fwu_gpt.c | 104 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 134 insertions(+)
 create mode 100644 lib/fwu_updates/Makefile
 create mode 100644 lib/fwu_updates/fwu.c
 create mode 100644 lib/fwu_updates/fwu_gpt.c

diff --git a/include/fwu.h b/include/fwu.h
index 8259c75d12..f14175cc9a 100644
--- a/include/fwu.h
+++ b/include/fwu.h
@@ -51,4 +51,5 @@ int fwu_clear_accept_image(efi_guid_t *img_type_id, u32 bank);
 
 int fwu_plat_get_alt_num(struct udevice *dev, efi_guid_t *image_guid,
 			 int *alt_num);
+int fwu_plat_get_update_index(u32 *update_idx);
 #endif /* _FWU_H_ */
diff --git a/lib/fwu_updates/Makefile b/lib/fwu_updates/Makefile
new file mode 100644
index 0000000000..1993088e5b
--- /dev/null
+++ b/lib/fwu_updates/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Copyright (c) 2022, Linaro Limited
+#
+
+obj-$(CONFIG_FWU_MULTI_BANK_UPDATE) += fwu.o
+obj-$(CONFIG_FWU_MDATA_GPT_BLK) += fwu_gpt.o
diff --git a/lib/fwu_updates/fwu.c b/lib/fwu_updates/fwu.c
new file mode 100644
index 0000000000..9808036eec
--- /dev/null
+++ b/lib/fwu_updates/fwu.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#include <fwu.h>
+#include <fwu_mdata.h>
+
+__weak int fwu_plat_get_update_index(u32 *update_idx)
+{
+	int ret;
+	u32 active_idx;
+
+	ret = fwu_get_active_index(&active_idx);
+
+	if (ret < 0)
+		return -1;
+
+	*update_idx = active_idx ^= 0x1;
+
+	return ret;
+}
diff --git a/lib/fwu_updates/fwu_gpt.c b/lib/fwu_updates/fwu_gpt.c
new file mode 100644
index 0000000000..b7ccca3645
--- /dev/null
+++ b/lib/fwu_updates/fwu_gpt.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2022, Linaro Limited
+ */
+
+#include <blk.h>
+#include <dfu.h>
+#include <efi.h>
+#include <efi_loader.h>
+#include <fwu.h>
+#include <log.h>
+#include <part.h>
+
+#include <linux/errno.h>
+
+static int get_gpt_dfu_identifier(struct blk_desc *desc, efi_guid_t *image_guid)
+{
+	int i;
+	struct disk_partition info;
+	efi_guid_t unique_part_guid;
+
+	for (i = 1; i < MAX_SEARCH_PARTITIONS; i++) {
+		if (part_get_info(desc, i, &info))
+			continue;
+		uuid_str_to_bin(info.uuid, unique_part_guid.b,
+				UUID_STR_FORMAT_GUID);
+
+		if (!guidcmp(&unique_part_guid, image_guid))
+			return i;
+	}
+
+	log_err("No partition found with image_guid %pUs\n", image_guid);
+	return -ENOENT;
+}
+
+static int fwu_gpt_get_alt_num(struct blk_desc *desc, efi_guid_t *image_guid,
+			       int *alt_num, unsigned char dfu_dev)
+{
+	int ret = -1;
+	int i, part, dev_num;
+	int nalt;
+	struct dfu_entity *dfu;
+
+	dev_num = desc->devnum;
+	part = get_gpt_dfu_identifier(desc, image_guid);
+	if (part < 0)
+		return -ENOENT;
+
+	dfu_init_env_entities(NULL, NULL);
+
+	nalt = 0;
+	list_for_each_entry(dfu, &dfu_list, list) {
+		nalt++;
+	}
+
+	if (!nalt) {
+		log_warning("No entities in dfu_alt_info\n");
+		dfu_free_entities();
+		return -ENOENT;
+	}
+
+	for (i = 0; i < nalt; i++) {
+		dfu = dfu_get_entity(i);
+
+		if (!dfu)
+			continue;
+
+		/*
+		 * Currently, Multi Bank update
+		 * feature is being supported
+		 * only on GPT partitioned
+		 * MMC/SD devices.
+		 */
+		if (dfu->dev_type != dfu_dev)
+			continue;
+
+		if (dfu->layout == DFU_RAW_ADDR &&
+		    dfu->data.mmc.dev_num == dev_num &&
+		    dfu->data.mmc.part == part) {
+			*alt_num = dfu->alt;
+			ret = 0;
+			break;
+		}
+	}
+
+	dfu_free_entities();
+
+	return ret;
+}
+
+__weak int fwu_plat_get_alt_num(struct udevice *dev, efi_guid_t *image_guid,
+				int *alt_num)
+{
+	struct blk_desc *desc;
+	struct fwu_mdata_gpt_blk_priv *priv = dev_get_priv(dev);
+
+	desc = dev_get_uclass_plat(priv->blk_dev);
+	if (!desc) {
+		log_err("Block device not found\n");
+		return -ENODEV;
+	}
+
+	return fwu_gpt_get_alt_num(desc, image_guid, alt_num, DFU_DEV_MMC);
+}
-- 
2.34.1