xref: /openbmc/qemu/include/hw/nvram/bcm2835_otp.h (revision c1bf7540)
1 /*
2  * BCM2835 One-Time Programmable (OTP) Memory
3  *
4  * Copyright (c) 2024 Rayhan Faizel <rayhan.faizel@gmail.com>
5  *
6  * SPDX-License-Identifier: MIT
7  */
8 
9 #ifndef BCM2835_OTP_H
10 #define BCM2835_OTP_H
11 
12 #include "hw/sysbus.h"
13 #include "qom/object.h"
14 
15 #define TYPE_BCM2835_OTP "bcm2835-otp"
16 OBJECT_DECLARE_SIMPLE_TYPE(BCM2835OTPState, BCM2835_OTP)
17 
18 #define BCM2835_OTP_ROW_COUNT                              66
19 
20 /* https://elinux.org/BCM2835_registers#OTP */
21 #define BCM2835_OTP_BOOTMODE_REG                         0x00
22 #define BCM2835_OTP_CONFIG_REG                           0x04
23 #define BCM2835_OTP_CTRL_LO_REG                          0x08
24 #define BCM2835_OTP_CTRL_HI_REG                          0x0c
25 #define BCM2835_OTP_STATUS_REG                           0x10
26 #define BCM2835_OTP_BITSEL_REG                           0x14
27 #define BCM2835_OTP_DATA_REG                             0x18
28 #define BCM2835_OTP_ADDR_REG                             0x1c
29 #define BCM2835_OTP_WRITE_DATA_READ_REG                  0x20
30 #define BCM2835_OTP_INIT_STATUS_REG                      0x24
31 
32 
33 /* -- Row 32: Undocumented -- */
34 
35 #define BCM2835_OTP_ROW_32                                 32
36 
37 /* Lock OTP Programming (Customer OTP and private key) */
38 #define BCM2835_OTP_ROW_32_LOCK                        BIT(6)
39 
40 /* -- Row 36-43: Customer OTP -- */
41 
42 #define BCM2835_OTP_CUSTOMER_OTP                           36
43 #define BCM2835_OTP_CUSTOMER_OTP_LEN                        8
44 
45 /* Magic numbers to lock programming of customer OTP and private key */
46 #define BCM2835_OTP_LOCK_NUM1                      0xffffffff
47 #define BCM2835_OTP_LOCK_NUM2                      0xaffe0000
48 
49 /* -- Row 56-63: Device-specific private key -- */
50 
51 #define BCM2835_OTP_PRIVATE_KEY                            56
52 #define BCM2835_OTP_PRIVATE_KEY_LEN                         8
53 
54 
55 struct BCM2835OTPState {
56     /* <private> */
57     SysBusDevice parent_obj;
58 
59     /* <public> */
60     MemoryRegion iomem;
61     uint32_t otp_rows[BCM2835_OTP_ROW_COUNT];
62 };
63 
64 
65 uint32_t bcm2835_otp_get_row(BCM2835OTPState *s, unsigned int row);
66 void bcm2835_otp_set_row(BCM2835OTPState *s, unsigned int row, uint32_t value);
67 
68 #endif
69