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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NXP LPC18xx/43xx OTP memory NVMEM driver
4 *
5 * Copyright (c) 2016 Joachim Eastwood <manabian@gmail.com>
6 *
7 * Based on the imx ocotp driver,
8 * Copyright (c) 2015 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
9 *
10 * TODO: add support for writing OTP register via API in boot ROM.
11 */
12
13#include <linux/io.h>
14#include <linux/module.h>
15#include <linux/nvmem-provider.h>
16#include <linux/of.h>
17#include <linux/platform_device.h>
18#include <linux/slab.h>
19
20/*
21 * LPC18xx OTP memory contains 4 banks with 4 32-bit words. Bank 0 starts
22 * at offset 0 from the base.
23 *
24 * Bank 0 contains the part ID for Flashless devices and is reserved for
25 * devices with Flash.
26 * Bank 1/2 is generale purpose or AES key storage for secure devices.
27 * Bank 3 contains control data, USB ID and generale purpose words.
28 */
29#define LPC18XX_OTP_NUM_BANKS 4
30#define LPC18XX_OTP_WORDS_PER_BANK 4
31#define LPC18XX_OTP_WORD_SIZE sizeof(u32)
32#define LPC18XX_OTP_SIZE (LPC18XX_OTP_NUM_BANKS * \
33 LPC18XX_OTP_WORDS_PER_BANK * \
34 LPC18XX_OTP_WORD_SIZE)
35
36struct lpc18xx_otp {
37 void __iomem *base;
38};
39
40static int lpc18xx_otp_read(void *context, unsigned int offset,
41 void *val, size_t bytes)
42{
43 struct lpc18xx_otp *otp = context;
44 unsigned int count = bytes >> 2;
45 u32 index = offset >> 2;
46 u32 *buf = val;
47 int i;
48
49 if (count > (LPC18XX_OTP_SIZE - index))
50 count = LPC18XX_OTP_SIZE - index;
51
52 for (i = index; i < (index + count); i++)
53 *buf++ = readl(otp->base + i * LPC18XX_OTP_WORD_SIZE);
54
55 return 0;
56}
57
58static struct nvmem_config lpc18xx_otp_nvmem_config = {
59 .name = "lpc18xx-otp",
60 .read_only = true,
61 .word_size = LPC18XX_OTP_WORD_SIZE,
62 .stride = LPC18XX_OTP_WORD_SIZE,
63 .reg_read = lpc18xx_otp_read,
64};
65
66static int lpc18xx_otp_probe(struct platform_device *pdev)
67{
68 struct nvmem_device *nvmem;
69 struct lpc18xx_otp *otp;
70
71 otp = devm_kzalloc(&pdev->dev, sizeof(*otp), GFP_KERNEL);
72 if (!otp)
73 return -ENOMEM;
74
75 otp->base = devm_platform_ioremap_resource(pdev, 0);
76 if (IS_ERR(otp->base))
77 return PTR_ERR(otp->base);
78
79 lpc18xx_otp_nvmem_config.size = LPC18XX_OTP_SIZE;
80 lpc18xx_otp_nvmem_config.dev = &pdev->dev;
81 lpc18xx_otp_nvmem_config.priv = otp;
82
83 nvmem = devm_nvmem_register(&pdev->dev, &lpc18xx_otp_nvmem_config);
84
85 return PTR_ERR_OR_ZERO(nvmem);
86}
87
88static const struct of_device_id lpc18xx_otp_dt_ids[] = {
89 { .compatible = "nxp,lpc1850-otp" },
90 { },
91};
92MODULE_DEVICE_TABLE(of, lpc18xx_otp_dt_ids);
93
94static struct platform_driver lpc18xx_otp_driver = {
95 .probe = lpc18xx_otp_probe,
96 .driver = {
97 .name = "lpc18xx_otp",
98 .of_match_table = lpc18xx_otp_dt_ids,
99 },
100};
101module_platform_driver(lpc18xx_otp_driver);
102
103MODULE_AUTHOR("Joachim Eastwoood <manabian@gmail.com>");
104MODULE_DESCRIPTION("NXP LPC18xx OTP NVMEM driver");
105MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NXP LPC18xx/43xx OTP memory NVMEM driver
4 *
5 * Copyright (c) 2016 Joachim Eastwood <manabian@gmail.com>
6 *
7 * Based on the imx ocotp driver,
8 * Copyright (c) 2015 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
9 *
10 * TODO: add support for writing OTP register via API in boot ROM.
11 */
12
13#include <linux/io.h>
14#include <linux/module.h>
15#include <linux/nvmem-provider.h>
16#include <linux/of.h>
17#include <linux/of_device.h>
18#include <linux/platform_device.h>
19#include <linux/slab.h>
20
21/*
22 * LPC18xx OTP memory contains 4 banks with 4 32-bit words. Bank 0 starts
23 * at offset 0 from the base.
24 *
25 * Bank 0 contains the part ID for Flashless devices and is reseverd for
26 * devices with Flash.
27 * Bank 1/2 is generale purpose or AES key storage for secure devices.
28 * Bank 3 contains control data, USB ID and generale purpose words.
29 */
30#define LPC18XX_OTP_NUM_BANKS 4
31#define LPC18XX_OTP_WORDS_PER_BANK 4
32#define LPC18XX_OTP_WORD_SIZE sizeof(u32)
33#define LPC18XX_OTP_SIZE (LPC18XX_OTP_NUM_BANKS * \
34 LPC18XX_OTP_WORDS_PER_BANK * \
35 LPC18XX_OTP_WORD_SIZE)
36
37struct lpc18xx_otp {
38 void __iomem *base;
39};
40
41static int lpc18xx_otp_read(void *context, unsigned int offset,
42 void *val, size_t bytes)
43{
44 struct lpc18xx_otp *otp = context;
45 unsigned int count = bytes >> 2;
46 u32 index = offset >> 2;
47 u32 *buf = val;
48 int i;
49
50 if (count > (LPC18XX_OTP_SIZE - index))
51 count = LPC18XX_OTP_SIZE - index;
52
53 for (i = index; i < (index + count); i++)
54 *buf++ = readl(otp->base + i * LPC18XX_OTP_WORD_SIZE);
55
56 return 0;
57}
58
59static struct nvmem_config lpc18xx_otp_nvmem_config = {
60 .name = "lpc18xx-otp",
61 .read_only = true,
62 .word_size = LPC18XX_OTP_WORD_SIZE,
63 .stride = LPC18XX_OTP_WORD_SIZE,
64 .reg_read = lpc18xx_otp_read,
65};
66
67static int lpc18xx_otp_probe(struct platform_device *pdev)
68{
69 struct nvmem_device *nvmem;
70 struct lpc18xx_otp *otp;
71 struct resource *res;
72
73 otp = devm_kzalloc(&pdev->dev, sizeof(*otp), GFP_KERNEL);
74 if (!otp)
75 return -ENOMEM;
76
77 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
78 otp->base = devm_ioremap_resource(&pdev->dev, res);
79 if (IS_ERR(otp->base))
80 return PTR_ERR(otp->base);
81
82 lpc18xx_otp_nvmem_config.size = LPC18XX_OTP_SIZE;
83 lpc18xx_otp_nvmem_config.dev = &pdev->dev;
84 lpc18xx_otp_nvmem_config.priv = otp;
85
86 nvmem = devm_nvmem_register(&pdev->dev, &lpc18xx_otp_nvmem_config);
87
88 return PTR_ERR_OR_ZERO(nvmem);
89}
90
91static const struct of_device_id lpc18xx_otp_dt_ids[] = {
92 { .compatible = "nxp,lpc1850-otp" },
93 { },
94};
95MODULE_DEVICE_TABLE(of, lpc18xx_otp_dt_ids);
96
97static struct platform_driver lpc18xx_otp_driver = {
98 .probe = lpc18xx_otp_probe,
99 .driver = {
100 .name = "lpc18xx_otp",
101 .of_match_table = lpc18xx_otp_dt_ids,
102 },
103};
104module_platform_driver(lpc18xx_otp_driver);
105
106MODULE_AUTHOR("Joachim Eastwoood <manabian@gmail.com>");
107MODULE_DESCRIPTION("NXP LPC18xx OTP NVMEM driver");
108MODULE_LICENSE("GPL v2");