1 /*
2 * Copyright (c) 2023, Nordic Semiconductor ASA
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #define DT_DRV_COMPAT zephyr_retained_ram
8
9 #include <string.h>
10 #include <zephyr/device.h>
11 #include <zephyr/devicetree.h>
12 #include <zephyr/drivers/retained_mem.h>
13 #include <zephyr/kernel.h>
14 #include <zephyr/sys/util.h>
15 #include <zephyr/logging/log.h>
16
17 LOG_MODULE_REGISTER(retained_mem_zephyr_ram, CONFIG_RETAINED_MEM_LOG_LEVEL);
18
19 #ifdef CONFIG_RETAINED_MEM_MUTEXES
20 struct zephyr_retained_mem_ram_data {
21 struct k_mutex lock;
22 };
23 #endif
24
25 struct zephyr_retained_mem_ram_config {
26 uint8_t *address;
27 size_t size;
28 };
29
zephyr_retained_mem_ram_lock_take(const struct device * dev)30 static inline void zephyr_retained_mem_ram_lock_take(const struct device *dev)
31 {
32 #ifdef CONFIG_RETAINED_MEM_MUTEXES
33 struct zephyr_retained_mem_ram_data *data = dev->data;
34
35 k_mutex_lock(&data->lock, K_FOREVER);
36 #else
37 ARG_UNUSED(dev);
38 #endif
39 }
40
zephyr_retained_mem_ram_lock_release(const struct device * dev)41 static inline void zephyr_retained_mem_ram_lock_release(const struct device *dev)
42 {
43 #ifdef CONFIG_RETAINED_MEM_MUTEXES
44 struct zephyr_retained_mem_ram_data *data = dev->data;
45
46 k_mutex_unlock(&data->lock);
47 #else
48 ARG_UNUSED(dev);
49 #endif
50 }
51
zephyr_retained_mem_ram_init(const struct device * dev)52 static int zephyr_retained_mem_ram_init(const struct device *dev)
53 {
54 #ifdef CONFIG_RETAINED_MEM_MUTEXES
55 struct zephyr_retained_mem_ram_data *data = dev->data;
56
57 k_mutex_init(&data->lock);
58 #endif
59
60 return 0;
61 }
62
zephyr_retained_mem_ram_size(const struct device * dev)63 static ssize_t zephyr_retained_mem_ram_size(const struct device *dev)
64 {
65 const struct zephyr_retained_mem_ram_config *config = dev->config;
66
67 return (ssize_t)config->size;
68 }
69
zephyr_retained_mem_ram_read(const struct device * dev,off_t offset,uint8_t * buffer,size_t size)70 static int zephyr_retained_mem_ram_read(const struct device *dev, off_t offset, uint8_t *buffer,
71 size_t size)
72 {
73 const struct zephyr_retained_mem_ram_config *config = dev->config;
74
75 zephyr_retained_mem_ram_lock_take(dev);
76
77 memcpy(buffer, (config->address + offset), size);
78
79 zephyr_retained_mem_ram_lock_release(dev);
80
81 return 0;
82 }
83
zephyr_retained_mem_ram_write(const struct device * dev,off_t offset,const uint8_t * buffer,size_t size)84 static int zephyr_retained_mem_ram_write(const struct device *dev, off_t offset,
85 const uint8_t *buffer, size_t size)
86 {
87 const struct zephyr_retained_mem_ram_config *config = dev->config;
88
89 zephyr_retained_mem_ram_lock_take(dev);
90
91 memcpy((config->address + offset), buffer, size);
92
93 zephyr_retained_mem_ram_lock_release(dev);
94
95 return 0;
96 }
97
zephyr_retained_mem_ram_clear(const struct device * dev)98 static int zephyr_retained_mem_ram_clear(const struct device *dev)
99 {
100 const struct zephyr_retained_mem_ram_config *config = dev->config;
101
102 zephyr_retained_mem_ram_lock_take(dev);
103
104 memset(config->address, 0, config->size);
105
106 zephyr_retained_mem_ram_lock_release(dev);
107
108 return 0;
109 }
110
111 static const struct retained_mem_driver_api zephyr_retained_mem_ram_api = {
112 .size = zephyr_retained_mem_ram_size,
113 .read = zephyr_retained_mem_ram_read,
114 .write = zephyr_retained_mem_ram_write,
115 .clear = zephyr_retained_mem_ram_clear,
116 };
117
118 #define ZEPHYR_RETAINED_MEM_RAM_DEVICE(inst) \
119 IF_ENABLED(CONFIG_RETAINED_MEM_MUTEXES, \
120 (static struct zephyr_retained_mem_ram_data \
121 zephyr_retained_mem_ram_data_##inst;) \
122 ) \
123 static const struct zephyr_retained_mem_ram_config \
124 zephyr_retained_mem_ram_config_##inst = { \
125 .address = (uint8_t *)DT_REG_ADDR(DT_PARENT(DT_INST(inst, DT_DRV_COMPAT))), \
126 .size = DT_REG_SIZE(DT_PARENT(DT_INST(inst, DT_DRV_COMPAT))), \
127 }; \
128 DEVICE_DT_INST_DEFINE(inst, \
129 &zephyr_retained_mem_ram_init, \
130 NULL, \
131 COND_CODE_1(CONFIG_RETAINED_MEM_MUTEXES, \
132 (&zephyr_retained_mem_ram_data_##inst), (NULL) \
133 ), \
134 &zephyr_retained_mem_ram_config_##inst, \
135 POST_KERNEL, \
136 CONFIG_RETAINED_MEM_INIT_PRIORITY, \
137 &zephyr_retained_mem_ram_api);
138
139 DT_INST_FOREACH_STATUS_OKAY(ZEPHYR_RETAINED_MEM_RAM_DEVICE)
140
