xref: /openbmc/qemu/include/hw/nvram/npcm7xx_otp.h (revision b4b9a0e3)
1 /*
2  * Nuvoton NPCM7xx OTP (Fuse Array) Interface
3  *
4  * Copyright 2020 Google LLC
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the
8  * Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14  * for more details.
15  */
16 #ifndef NPCM7XX_OTP_H
17 #define NPCM7XX_OTP_H
18 
19 #include "exec/memory.h"
20 #include "hw/sysbus.h"
21 
22 /* Each OTP module holds 8192 bits of one-time programmable storage */
23 #define NPCM7XX_OTP_ARRAY_BITS (8192)
24 #define NPCM7XX_OTP_ARRAY_BYTES (NPCM7XX_OTP_ARRAY_BITS / BITS_PER_BYTE)
25 
26 /* Fuse array offsets */
27 #define NPCM7XX_FUSE_FUSTRAP (0)
28 #define NPCM7XX_FUSE_CP_FUSTRAP (12)
29 #define NPCM7XX_FUSE_DAC_CALIB (16)
30 #define NPCM7XX_FUSE_ADC_CALIB (24)
31 #define NPCM7XX_FUSE_DERIVATIVE (64)
32 #define NPCM7XX_FUSE_TEST_SIG (72)
33 #define NPCM7XX_FUSE_DIE_LOCATION (74)
34 #define NPCM7XX_FUSE_GP1 (80)
35 #define NPCM7XX_FUSE_GP2 (128)
36 
37 /*
38  * Number of registers in our device state structure. Don't change this without
39  * incrementing the version_id in the vmstate.
40  */
41 #define NPCM7XX_OTP_NR_REGS (0x18 / sizeof(uint32_t))
42 
43 /**
44  * struct NPCM7xxOTPState - Device state for one OTP module.
45  * @parent: System bus device.
46  * @mmio: Memory region through which registers are accessed.
47  * @regs: Register contents.
48  * @array: OTP storage array.
49  */
50 typedef struct NPCM7xxOTPState {
51     SysBusDevice parent;
52 
53     MemoryRegion mmio;
54     uint32_t regs[NPCM7XX_OTP_NR_REGS];
55     uint8_t array[NPCM7XX_OTP_ARRAY_BYTES];
56 } NPCM7xxOTPState;
57 
58 #define TYPE_NPCM7XX_OTP "npcm7xx-otp"
59 #define NPCM7XX_OTP(obj) OBJECT_CHECK(NPCM7xxOTPState, (obj), TYPE_NPCM7XX_OTP)
60 
61 #define TYPE_NPCM7XX_KEY_STORAGE "npcm7xx-key-storage"
62 #define TYPE_NPCM7XX_FUSE_ARRAY "npcm7xx-fuse-array"
63 
64 typedef struct NPCM7xxOTPClass NPCM7xxOTPClass;
65 
66 /**
67  * npcm7xx_otp_array_write - ECC encode and write data to OTP array.
68  * @s: OTP module.
69  * @data: Data to be encoded and written.
70  * @offset: Offset of first byte to be written in the OTP array.
71  * @len: Number of bytes before ECC encoding.
72  *
73  * Each nibble of data is encoded into a byte, so the number of bytes written
74  * to the array will be @len * 2.
75  */
76 extern void npcm7xx_otp_array_write(NPCM7xxOTPState *s, const void *data,
77                                     unsigned int offset, unsigned int len);
78 
79 #endif /* NPCM7XX_OTP_H */
80