1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * (C) Copyright 2017
4  * Mario Six,  Guntermann & Drunck GmbH, mario.six@gdsys.cc
5  */
6 
7 struct udevice;
8 
9 /*
10  * This uclass encapsulates hardware methods to gather information about a
11  * sysinfo or a specific device such as hard-wired GPIOs on GPIO expanders,
12  * read-only data in flash ICs, or similar.
13  *
14  * The interface offers functions to read the usual standard data types (bool,
15  * int, string) from the device, each of which is identified by a static
16  * numeric ID (which will usually be defined as a enum in a header file).
17  *
18  * If for example the sysinfo had a read-only serial number flash IC, we could
19  * call
20  *
21  * ret = sysinfo_detect(dev);
22  * if (ret) {
23  *	debug("sysinfo device not found.");
24  *	return ret;
25  * }
26  *
27  * ret = sysinfo_get_int(dev, ID_SERIAL_NUMBER, &serial);
28  * if (ret) {
29  *	debug("Error when reading serial number from device.");
30  *	return ret;
31  * }
32  *
33  * to read the serial number.
34  */
35 
36 /** enum sysinfo_id - Standard IDs defined by U-Boot */
37 enum sysinfo_id {
38 	SYSINFO_ID_NONE,
39 
40 	SYSINFO_ID_SMBIOS_SYSTEM_VERSION,
41 	SYSINFO_ID_SMBIOS_BASEBOARD_VERSION,
42 
43 	/* First value available for downstream/board used */
44 	SYSINFO_ID_USER = 0x1000,
45 };
46 
47 struct sysinfo_ops {
48 	/**
49 	 * detect() - Run the hardware info detection procedure for this
50 	 *	      device.
51 	 * @dev:      The device containing the information
52 	 *
53 	 * This operation might take a long time (e.g. read from EEPROM,
54 	 * check the presence of a device on a bus etc.), hence this is not
55 	 * done in the probe() method, but later during operation in this
56 	 * dedicated method.
57 	 *
58 	 * Return: 0 if OK, -ve on error.
59 	 */
60 	int (*detect)(struct udevice *dev);
61 
62 	/**
63 	 * get_bool() - Read a specific bool data value that describes the
64 	 *		hardware setup.
65 	 * @dev:	The sysinfo instance to gather the data.
66 	 * @id:		A unique identifier for the bool value to be read.
67 	 * @val:	Pointer to a buffer that receives the value read.
68 	 *
69 	 * Return: 0 if OK, -ve on error.
70 	 */
71 	int (*get_bool)(struct udevice *dev, int id, bool *val);
72 
73 	/**
74 	 * get_int() - Read a specific int data value that describes the
75 	 *	       hardware setup.
76 	 * @dev:       The sysinfo instance to gather the data.
77 	 * @id:        A unique identifier for the int value to be read.
78 	 * @val:       Pointer to a buffer that receives the value read.
79 	 *
80 	 * Return: 0 if OK, -ve on error.
81 	 */
82 	int (*get_int)(struct udevice *dev, int id, int *val);
83 
84 	/**
85 	 * get_str() - Read a specific string data value that describes the
86 	 *	       hardware setup.
87 	 * @dev:	The sysinfo instance to gather the data.
88 	 * @id:		A unique identifier for the string value to be read.
89 	 * @size:	The size of the buffer to receive the string data.
90 	 * @val:	Pointer to a buffer that receives the value read.
91 	 *
92 	 * Return: 0 if OK, -ve on error.
93 	 */
94 	int (*get_str)(struct udevice *dev, int id, size_t size, char *val);
95 
96 	/**
97 	 * get_fit_loadable - Get the name of an image to load from FIT
98 	 * This function can be used to provide the image names based on runtime
99 	 * detection. A classic use-case would when DTBOs are used to describe
100 	 * additionnal daughter cards.
101 	 *
102 	 * @dev:	The sysinfo instance to gather the data.
103 	 * @index:	Index of the image. Starts at 0 and gets incremented
104 	 *		after each call to this function.
105 	 * @type:	The type of image. For example, "fdt" for DTBs
106 	 * @strp:	A pointer to string. Untouched if the function fails
107 	 *
108 	 * Return: 0 if OK, -ENOENT if no loadable is available else -ve on
109 	 * error.
110 	 */
111 	int (*get_fit_loadable)(struct udevice *dev, int index,
112 				const char *type, const char **strp);
113 };
114 
115 #define sysinfo_get_ops(dev)	((struct sysinfo_ops *)(dev)->driver->ops)
116 
117 #if CONFIG_IS_ENABLED(SYSINFO)
118 /**
119  * sysinfo_detect() - Run the hardware info detection procedure for this device.
120  *
121  * @dev:	The device containing the information
122  *
123  * Return: 0 if OK, -ve on error.
124  */
125 int sysinfo_detect(struct udevice *dev);
126 
127 /**
128  * sysinfo_get_bool() - Read a specific bool data value that describes the
129  *		      hardware setup.
130  * @dev:	The sysinfo instance to gather the data.
131  * @id:		A unique identifier for the bool value to be read.
132  * @val:	Pointer to a buffer that receives the value read.
133  *
134  * Return: 0 if OK, -ve on error.
135  */
136 int sysinfo_get_bool(struct udevice *dev, int id, bool *val);
137 
138 /**
139  * sysinfo_get_int() - Read a specific int data value that describes the
140  *		     hardware setup.
141  * @dev:	The sysinfo instance to gather the data.
142  * @id:		A unique identifier for the int value to be read.
143  * @val:	Pointer to a buffer that receives the value read.
144  *
145  * Return: 0 if OK, -ve on error.
146  */
147 int sysinfo_get_int(struct udevice *dev, int id, int *val);
148 
149 /**
150  * sysinfo_get_str() - Read a specific string data value that describes the
151  *		     hardware setup.
152  * @dev:	The sysinfo instance to gather the data.
153  * @id:		A unique identifier for the string value to be read.
154  * @size:	The size of the buffer to receive the string data.
155  * @val:	Pointer to a buffer that receives the value read.
156  *
157  * Return: 0 if OK, -ve on error.
158  */
159 int sysinfo_get_str(struct udevice *dev, int id, size_t size, char *val);
160 
161 /**
162  * sysinfo_get() - Return the sysinfo device for the sysinfo in question.
163  * @devp: Pointer to structure to receive the sysinfo device.
164  *
165  * Since there can only be at most one sysinfo instance, the API can supply a
166  * function that returns the unique device. This is especially useful for use
167  * in sysinfo files.
168  *
169  * Return: 0 if OK, -ve on error.
170  */
171 int sysinfo_get(struct udevice **devp);
172 
173 /**
174  * sysinfo_get_fit_loadable - Get the name of an image to load from FIT
175  * This function can be used to provide the image names based on runtime
176  * detection. A classic use-case would when DTBOs are used to describe
177  * additionnal daughter cards.
178  *
179  * @dev:	The sysinfo instance to gather the data.
180  * @index:	Index of the image. Starts at 0 and gets incremented
181  *		after each call to this function.
182  * @type:	The type of image. For example, "fdt" for DTBs
183  * @strp:	A pointer to string. Untouched if the function fails
184  *
185  *
186  * Return: 0 if OK, -ENOENT if no loadable is available else -ve on
187  * error.
188  */
189 int sysinfo_get_fit_loadable(struct udevice *dev, int index, const char *type,
190 			     const char **strp);
191 
192 #else
193 
sysinfo_detect(struct udevice * dev)194 static inline int sysinfo_detect(struct udevice *dev)
195 {
196 	return -ENOSYS;
197 }
198 
sysinfo_get_bool(struct udevice * dev,int id,bool * val)199 static inline int sysinfo_get_bool(struct udevice *dev, int id, bool *val)
200 {
201 	return -ENOSYS;
202 }
203 
sysinfo_get_int(struct udevice * dev,int id,int * val)204 static inline int sysinfo_get_int(struct udevice *dev, int id, int *val)
205 {
206 	return -ENOSYS;
207 }
208 
sysinfo_get_str(struct udevice * dev,int id,size_t size,char * val)209 static inline int sysinfo_get_str(struct udevice *dev, int id, size_t size,
210 				  char *val)
211 {
212 	return -ENOSYS;
213 }
214 
sysinfo_get(struct udevice ** devp)215 static inline int sysinfo_get(struct udevice **devp)
216 {
217 	return -ENOSYS;
218 }
219 
sysinfo_get_fit_loadable(struct udevice * dev,int index,const char * type,const char ** strp)220 static inline int sysinfo_get_fit_loadable(struct udevice *dev, int index,
221 					   const char *type, const char **strp)
222 {
223 	return -ENOSYS;
224 }
225 
226 #endif
227