1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Core ACPI (Advanced Configuration and Power Interface) support
4  *
5  * Copyright 2019 Google LLC
6  * Written by Simon Glass <sjg@chromium.org>
7  */
8 
9 #ifndef __DM_ACPI_H__
10 #define __DM_ACPI_H__
11 
12 /* Allow operations to be optional for ACPI */
13 #if CONFIG_IS_ENABLED(ACPIGEN)
14 #define ACPI_OPS_PTR(_ptr)	.acpi_ops	= _ptr,
15 #else
16 #define ACPI_OPS_PTR(_ptr)
17 #endif
18 
19 /* Length of an ACPI name string, excluding null terminator */
20 #define ACPI_NAME_LEN	4
21 
22 /* Length of an ACPI name string including nul terminator */
23 #define ACPI_NAME_MAX	(ACPI_NAME_LEN + 1)
24 
25 /* Number of nested objects supported */
26 #define ACPIGEN_LENSTACK_SIZE 10
27 
28 #if !defined(__ACPI__)
29 
30 struct nhlt;
31 struct udevice;
32 
33 /** enum acpi_dump_option - selects what ACPI information to dump */
34 enum acpi_dump_option {
35 	ACPI_DUMP_LIST,		/* Just the list of items */
36 	ACPI_DUMP_CONTENTS,	/* Include the binary contents also */
37 };
38 
39 /**
40  * struct acpi_ctx - Context used for writing ACPI tables
41  *
42  * This contains a few useful pieces of information used when writing
43  *
44  * @base: Base address of ACPI tables
45  * @current: Current address for writing
46  * @rsdp: Pointer to the Root System Description Pointer, typically used when
47  *	adding a new table. The RSDP holds pointers to the RSDT and XSDT.
48  * @rsdt: Pointer to the Root System Description Table
49  * @xsdt: Pointer to the Extended System Description Table
50  * @nhlt: Intel Non-High-Definition-Audio Link Table (NHLT) pointer, used to
51  *	build up information that audio codecs need to provide in the NHLT ACPI
52  *	table
53  * @len_stack: Stack of 'length' words to fix up later
54  * @ltop: Points to current top of stack (0 = empty)
55  */
56 struct acpi_ctx {
57 	void *base;
58 	void *current;
59 	struct acpi_rsdp *rsdp;
60 	struct acpi_rsdt *rsdt;
61 	struct acpi_xsdt *xsdt;
62 	struct nhlt *nhlt;
63 	char *len_stack[ACPIGEN_LENSTACK_SIZE];
64 	int ltop;
65 };
66 
67 /**
68  * struct acpi_ops - ACPI operations supported by driver model
69  */
70 struct acpi_ops {
71 	/**
72 	 * get_name() - Obtain the ACPI name of a device
73 	 *
74 	 * @dev: Device to check
75 	 * @out_name: Place to put the name, must hold at least ACPI_NAME_MAX
76 	 *	bytes
77 	 * @return 0 if OK, -ENOENT if no name is available, other -ve value on
78 	 *	other error
79 	 */
80 	int (*get_name)(const struct udevice *dev, char *out_name);
81 
82 	/**
83 	 * write_tables() - Write out any tables required by this device
84 	 *
85 	 * @dev: Device to write
86 	 * @ctx: ACPI context to use
87 	 * @return 0 if OK, -ve on error
88 	 */
89 	int (*write_tables)(const struct udevice *dev, struct acpi_ctx *ctx);
90 
91 	/**
92 	 * fill_ssdt() - Generate SSDT code for a device
93 	 *
94 	 * This is called to create the SSDT code. The method should write out
95 	 * whatever ACPI code is needed by this device. It will end up in the
96 	 * SSDT table.
97 	 *
98 	 * Note that this is called 'fill' because the entire contents of the
99 	 * SSDT is build by calling this method on all devices.
100 	 *
101 	 * @dev: Device to write
102 	 * @ctx: ACPI context to use
103 	 * @return 0 if OK, -ve on error
104 	 */
105 	int (*fill_ssdt)(const struct udevice *dev, struct acpi_ctx *ctx);
106 
107 	/**
108 	 * inject_dsdt() - Generate DSDT code for a device
109 	 *
110 	 * This is called to create the DSDT code. The method should write out
111 	 * whatever ACPI code is needed by this device. It will end up in the
112 	 * DSDT table.
113 	 *
114 	 * Note that this is called 'inject' because the output of calling this
115 	 * method on all devices is injected into the DSDT, the bulk of which
116 	 * is written in .asl files for the board.
117 	 *
118 	 * @dev: Device to write
119 	 * @ctx: ACPI context to use
120 	 * @return 0 if OK, -ve on error
121 	 */
122 	int (*inject_dsdt)(const struct udevice *dev, struct acpi_ctx *ctx);
123 
124 	/**
125 	 * setup_nhlt() - Set up audio information for this device
126 	 *
127 	 * The method can add information to ctx->nhlt if it likes
128 	 *
129 	 * @return 0 if OK, -ENODATA if nothing to add, -ve on error
130 	 */
131 	int (*setup_nhlt)(const struct udevice *dev, struct acpi_ctx *ctx);
132 };
133 
134 #define device_get_acpi_ops(dev)	((dev)->driver->acpi_ops)
135 
136 /**
137  * acpi_get_name() - Obtain the ACPI name of a device
138  *
139  * @dev: Device to check
140  * @out_name: Place to put the name, must hold at least ACPI_NAME_MAX
141  *	bytes
142  * @return 0 if OK, -ENOENT if no name is available, other -ve value on
143  *	other error
144  */
145 int acpi_get_name(const struct udevice *dev, char *out_name);
146 
147 /**
148  * acpi_copy_name() - Copy an ACPI name to an output buffer
149  *
150  * This convenience function can be used to return a literal string as a name
151  * in functions that implement the get_name() method.
152  *
153  * For example:
154  *
155  *	static int mydev_get_name(const struct udevice *dev, char *out_name)
156  *	{
157  *		return acpi_copy_name(out_name, "WIBB");
158  *	}
159  *
160  * @out_name: Place to put the name
161  * @name: Name to copy
162  * @return 0 (always)
163  */
164 int acpi_copy_name(char *out_name, const char *name);
165 
166 /**
167  * acpi_write_dev_tables() - Write ACPI tables required by devices
168  *
169  * This scans through all devices and tells them to write any tables they want
170  * to write.
171  *
172  * @return 0 if OK, -ve if any device returned an error
173  */
174 int acpi_write_dev_tables(struct acpi_ctx *ctx);
175 
176 /**
177  * acpi_fill_ssdt() - Generate ACPI tables for SSDT
178  *
179  * This is called to create the SSDT code for all devices.
180  *
181  * @ctx: ACPI context to use
182  * @return 0 if OK, -ve on error
183  */
184 int acpi_fill_ssdt(struct acpi_ctx *ctx);
185 
186 /**
187  * acpi_inject_dsdt() - Generate ACPI tables for DSDT
188  *
189  * This is called to create the DSDT code for all devices.
190  *
191  * @ctx: ACPI context to use
192  * @return 0 if OK, -ve on error
193  */
194 int acpi_inject_dsdt(struct acpi_ctx *ctx);
195 
196 /**
197  * acpi_setup_nhlt() - Set up audio information
198  *
199  * This is called to set up the nhlt information for all devices.
200  *
201  * @ctx: ACPI context to use
202  * @nhlt: Pointer to nhlt information to add to
203  * @return 0 if OK, -ve on error
204  */
205 int acpi_setup_nhlt(struct acpi_ctx *ctx, struct nhlt *nhlt);
206 
207 /**
208  * acpi_dump_items() - Dump out the collected ACPI items
209  *
210  * This lists the ACPI DSDT and SSDT items generated by the various U-Boot
211  * drivers.
212  *
213  * @option: Sets what should be dumpyed
214  */
215 void acpi_dump_items(enum acpi_dump_option option);
216 
217 /**
218  * acpi_get_path() - Get the full ACPI path for a device
219  *
220  * This checks for any override in the device tree and calls acpi_device_path()
221  * if not
222  *
223  * @dev: Device to check
224  * @out_path: Buffer to place the path in (should be ACPI_PATH_MAX long)
225  * @maxlen: Size of buffer (typically ACPI_PATH_MAX)
226  * @return 0 if OK, -ve on error
227  */
228 int acpi_get_path(const struct udevice *dev, char *out_path, int maxlen);
229 
230 /**
231  * acpi_reset_items() - Reset the list of ACPI items to empty
232  *
233  * This list keeps track of DSDT and SSDT items that are generated
234  * programmatically. The 'acpi items' command shows the list. Use this function
235  * to empty the list, before writing new items.
236  */
237 void acpi_reset_items(void);
238 
239 #endif /* __ACPI__ */
240 
241 #endif
242