--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2020 Linaro Limited
+ */
+
+#include <common.h>
+#include <dfu.h>
+#include <env.h>
+#include <memalign.h>
+#include <mtd.h>
+
+#define DFU_ALT_BUF_LEN SZ_1K
+
+static void board_get_alt_info(struct mtd_info *mtd, char *buf)
+{
+ struct mtd_info *part;
+ bool first = true;
+ const char *name;
+ int len, partnum = 0;
+
+ name = mtd->name;
+ len = strlen(buf);
+
+ if (buf[0] != '\0')
+ len += snprintf(buf + len, DFU_ALT_BUF_LEN - len, "&");
+ len += snprintf(buf + len, DFU_ALT_BUF_LEN - len,
+ "mtd %s=", name);
+
+ list_for_each_entry(part, &mtd->partitions, node) {
+ partnum++;
+ if (!first)
+ len += snprintf(buf + len, DFU_ALT_BUF_LEN - len, ";");
+ first = false;
+
+ len += snprintf(buf + len, DFU_ALT_BUF_LEN - len,
+ "%s part %d",
+ part->name, partnum);
+ }
+}
+
+void set_dfu_alt_info(char *interface, char *devstr)
+{
+ struct mtd_info *mtd;
+
+ ALLOC_CACHE_ALIGN_BUFFER(char, buf, DFU_ALT_BUF_LEN);
+
+ if (env_get("dfu_alt_info"))
+ return;
+
+ memset(buf, 0, sizeof(buf));
+
+ /*
+ * Currently dfu_alt_info is needed on Qemu ARM64 for
+ * capsule updates
+ */
+ if (IS_ENABLED(CONFIG_EFI_CAPSULE_FIRMWARE_MANAGEMENT) &&
+ IS_ENABLED(CONFIG_TARGET_QEMU_ARM_64BIT)) {
+ /* probe all MTD devices */
+ mtd_probe_devices();
+
+ mtd = get_mtd_device_nm("nor0");
+ if (!IS_ERR_OR_NULL(mtd))
+ board_get_alt_info(mtd, buf);
+ }
+
+ env_set("dfu_alt_info", buf);
+ printf("dfu_alt_info set\n");
+}