hw/nvram/aspeed_otp: Add ASPEED OTP memory device model

Introduce a QEMU device model for ASPEED's One-Time Programmable (OTP)
memory.

This model simulates a word-addressable OTP region used for secure
fuse storage. The OTP memory can operate with an internal memory
buffer.

The OTP model provides a memory-like interface through a dedicated
AddressSpace, allowing other device models (e.g., SBC) to issue
transactions as if accessing a memory-mapped region.

Signed-off-by: Kane-Chen-AS <kane_chen@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250812094011.2617526-2-kane_chen@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

include/hw/nvram/aspeed_otp.h

@@ -0,0 +1,33 @@
+/*
+ *  ASPEED OTP (One-Time Programmable) memory
+ *
+ *  Copyright (C) 2025 Aspeed
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef ASPEED_OTP_H
+#define ASPEED_OTP_H
+
+#include "system/memory.h"
+#include "hw/block/block.h"
+#include "system/address-spaces.h"
+
+#define TYPE_ASPEED_OTP "aspeed-otp"
+OBJECT_DECLARE_SIMPLE_TYPE(AspeedOTPState, ASPEED_OTP)
+
+typedef struct AspeedOTPState {
+    DeviceState parent_obj;
+
+    BlockBackend *blk;
+
+    uint64_t size;
+
+    AddressSpace as;
+
+    MemoryRegion mmio;
+
+    uint8_t *storage;
+} AspeedOTPState;
+
+#endif /* ASPEED_OTP_H */