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 #include <linker_lists.h>
31 
32 struct nhlt;
33 struct udevice;
34 
35 /** enum acpi_dump_option - selects what ACPI information to dump */
36 enum acpi_dump_option {
37 	ACPI_DUMP_LIST,		/* Just the list of items */
38 	ACPI_DUMP_CONTENTS,	/* Include the binary contents also */
39 };
40 
41 /**
42  * struct acpi_ctx - Context used for writing ACPI tables
43  *
44  * This contains a few useful pieces of information used when writing
45  *
46  * @base: Base address of ACPI tables
47  * @current: Current address for writing
48  * @tab_start: Address of start of the table being written. This is set up
49  * before the writer or driver method is called. It must not be changed by the
50  * method
51  * @rsdp: Pointer to the Root System Description Pointer, typically used when
52  *	adding a new table. The RSDP holds pointers to the RSDT and XSDT.
53  * @rsdt: Pointer to the Root System Description Table
54  * @xsdt: Pointer to the Extended System Description Table
55  * @facs: Pointer to the Firmware ACPI Control Structure
56  * @dsdt: Pointer to the Differentiated System Description Table
57  * @nhlt: Intel Non-High-Definition-Audio Link Table (NHLT) pointer, used to
58  *	build up information that audio codecs need to provide in the NHLT ACPI
59  *	table
60  * @len_stack: Stack of 'length' words to fix up later
61  * @ltop: Points to current top of stack (0 = empty)
62  */
63 struct acpi_ctx {
64 	void *base;
65 	void *current;
66 	void *tab_start;
67 	struct acpi_rsdp *rsdp;
68 	struct acpi_rsdt *rsdt;
69 	struct acpi_xsdt *xsdt;
70 	struct acpi_facs *facs;
71 	struct acpi_table_header *dsdt;
72 	struct nhlt *nhlt;
73 	char *len_stack[ACPIGEN_LENSTACK_SIZE];
74 	int ltop;
75 };
76 
77 /**
78  * enum acpi_writer_flags_t - flags to use for the ACPI writers
79  *
80  * ACPIWF_ALIGN64 - align to 64 bytes after writing this one (default is 16)
81  */
82 enum acpi_writer_flags_t {
83 	ACPIWF_ALIGN64	= 1 << 0,
84 };
85 
86 struct acpi_writer;
87 
88 /**
89  * acpi_writer_func() - Function that can write an ACPI table
90  *
91  * @ctx: ACPI context to use for writing
92  * @entry: Linker-list entry for this writer
93  * @return 0 if OK, -ve on error
94  */
95 typedef int (*acpi_writer_func)(struct acpi_ctx *ctx,
96 				const struct acpi_writer *entry);
97 
98 /**
99  * struct acpi_writer - an ACPI table that can be written
100  *
101  * @name: Name of the writer
102  * @table: Table name that is generated (e.g. "DSDT")
103  * @h_write: Writer function
104  */
105 struct acpi_writer {
106 	const char *name;
107 	const char *table;
108 	acpi_writer_func h_write;
109 	int flags;
110 };
111 
112 /* Declare a new ACPI-table writer */
113 #define ACPI_WRITER(_name, _table, _write, _flags)					\
114 	ll_entry_declare(struct acpi_writer, _name, acpi_writer) = {	\
115 		.name = #_name,						\
116 		.table = _table,					\
117 		.h_write = _write,					\
118 		.flags = _flags,					\
119 	}
120 
121 /* Get a pointer to a given ACPI-table writer */
122 #define ACPI_WRITER_GET(_name)						\
123 	ll_entry_get(struct acpi_writer, _name, acpi_writer)
124 
125 /**
126  * struct acpi_ops - ACPI operations supported by driver model
127  */
128 struct acpi_ops {
129 	/**
130 	 * get_name() - Obtain the ACPI name of a device
131 	 *
132 	 * @dev: Device to check
133 	 * @out_name: Place to put the name, must hold at least ACPI_NAME_MAX
134 	 *	bytes
135 	 * @return 0 if OK, -ENOENT if no name is available, other -ve value on
136 	 *	other error
137 	 */
138 	int (*get_name)(const struct udevice *dev, char *out_name);
139 
140 	/**
141 	 * write_tables() - Write out any tables required by this device
142 	 *
143 	 * @dev: Device to write
144 	 * @ctx: ACPI context to use
145 	 * @return 0 if OK, -ve on error
146 	 */
147 	int (*write_tables)(const struct udevice *dev, struct acpi_ctx *ctx);
148 
149 	/**
150 	 * fill_ssdt() - Generate SSDT code for a device
151 	 *
152 	 * This is called to create the SSDT code. The method should write out
153 	 * whatever ACPI code is needed by this device. It will end up in the
154 	 * SSDT table.
155 	 *
156 	 * Note that this is called 'fill' because the entire contents of the
157 	 * SSDT is build by calling this method on all devices.
158 	 *
159 	 * @dev: Device to write
160 	 * @ctx: ACPI context to use
161 	 * @return 0 if OK, -ve on error
162 	 */
163 	int (*fill_ssdt)(const struct udevice *dev, struct acpi_ctx *ctx);
164 
165 	/**
166 	 * inject_dsdt() - Generate DSDT code for a device
167 	 *
168 	 * This is called to create the DSDT code. The method should write out
169 	 * whatever ACPI code is needed by this device. It will end up in the
170 	 * DSDT table.
171 	 *
172 	 * Note that this is called 'inject' because the output of calling this
173 	 * method on all devices is injected into the DSDT, the bulk of which
174 	 * is written in .asl files for the board.
175 	 *
176 	 * @dev: Device to write
177 	 * @ctx: ACPI context to use
178 	 * @return 0 if OK, -ve on error
179 	 */
180 	int (*inject_dsdt)(const struct udevice *dev, struct acpi_ctx *ctx);
181 
182 	/**
183 	 * setup_nhlt() - Set up audio information for this device
184 	 *
185 	 * The method can add information to ctx->nhlt if it likes
186 	 *
187 	 * @return 0 if OK, -ENODATA if nothing to add, -ve on error
188 	 */
189 	int (*setup_nhlt)(const struct udevice *dev, struct acpi_ctx *ctx);
190 };
191 
192 #define device_get_acpi_ops(dev)	((dev)->driver->acpi_ops)
193 
194 /**
195  * acpi_get_name() - Obtain the ACPI name of a device
196  *
197  * @dev: Device to check
198  * @out_name: Place to put the name, must hold at least ACPI_NAME_MAX
199  *	bytes
200  * Return: 0 if OK, -ENOENT if no name is available, other -ve value on
201  *	other error
202  */
203 int acpi_get_name(const struct udevice *dev, char *out_name);
204 
205 /**
206  * acpi_copy_name() - Copy an ACPI name to an output buffer
207  *
208  * This convenience function can be used to return a literal string as a name
209  * in functions that implement the get_name() method.
210  *
211  * For example:
212  *
213  *	static int mydev_get_name(const struct udevice *dev, char *out_name)
214  *	{
215  *		return acpi_copy_name(out_name, "WIBB");
216  *	}
217  *
218  * @out_name: Place to put the name
219  * @name: Name to copy
220  * Return: 0 (always)
221  */
222 int acpi_copy_name(char *out_name, const char *name);
223 
224 /**
225  * acpi_write_dev_tables() - Write ACPI tables required by devices
226  *
227  * This scans through all devices and tells them to write any tables they want
228  * to write.
229  *
230  * Return: 0 if OK, -ve if any device returned an error
231  */
232 int acpi_write_dev_tables(struct acpi_ctx *ctx);
233 
234 /**
235  * acpi_fill_ssdt() - Generate ACPI tables for SSDT
236  *
237  * This is called to create the SSDT code for all devices.
238  *
239  * @ctx: ACPI context to use
240  * Return: 0 if OK, -ve on error
241  */
242 int acpi_fill_ssdt(struct acpi_ctx *ctx);
243 
244 /**
245  * acpi_inject_dsdt() - Generate ACPI tables for DSDT
246  *
247  * This is called to create the DSDT code for all devices.
248  *
249  * @ctx: ACPI context to use
250  * Return: 0 if OK, -ve on error
251  */
252 int acpi_inject_dsdt(struct acpi_ctx *ctx);
253 
254 /**
255  * acpi_setup_nhlt() - Set up audio information
256  *
257  * This is called to set up the nhlt information for all devices.
258  *
259  * @ctx: ACPI context to use
260  * @nhlt: Pointer to nhlt information to add to
261  * Return: 0 if OK, -ve on error
262  */
263 int acpi_setup_nhlt(struct acpi_ctx *ctx, struct nhlt *nhlt);
264 
265 /**
266  * acpi_add_other_item() - Add a new table to the list of ACPI tables
267  *
268  * This adds an entry of type ACPIT_TYPE_OTHER
269  *
270  * @ctx: ACPI context
271  * @writer: Writer entry that generated the data
272  * @type: Table type it refers to
273  * @start: The start of the data (the end is obtained from ctx->current)
274  * @return 0 if OK, -ENOSPC if too many items, -ENOMEM if out of memory
275  */
276 int acpi_add_other_item(struct acpi_ctx *ctx, const struct acpi_writer *writer,
277 			void *start);
278 
279 /**
280  * acpi_dump_items() - Dump out the collected ACPI items
281  *
282  * This lists the ACPI DSDT and SSDT items generated by the various U-Boot
283  * drivers.
284  *
285  * @option: Sets what should be dumpyed
286  */
287 void acpi_dump_items(enum acpi_dump_option option);
288 
289 /**
290  * acpi_get_path() - Get the full ACPI path for a device
291  *
292  * This checks for any override in the device tree and calls acpi_device_path()
293  * if not
294  *
295  * @dev: Device to check
296  * @out_path: Buffer to place the path in (should be ACPI_PATH_MAX long)
297  * @maxlen: Size of buffer (typically ACPI_PATH_MAX)
298  * Return: 0 if OK, -ve on error
299  */
300 int acpi_get_path(const struct udevice *dev, char *out_path, int maxlen);
301 
302 /**
303  * acpi_reset_items() - Reset the list of ACPI items to empty
304  *
305  * This list keeps track of DSDT and SSDT items that are generated
306  * programmatically. The 'acpi items' command shows the list. Use this function
307  * to empty the list, before writing new items.
308  */
309 void acpi_reset_items(void);
310 
311 /**
312  * acpi_write_one() - Call a single ACPI writer entry
313  *
314  * This handles aligning the context afterwards, if the entry flags indicate
315  * that.
316  *
317  * @ctx: ACPI context to use
318  * @entry: Entry to call
319  * @return 0 if OK, -ENOENT if this writer produced an empty entry, other -ve
320  * value on error
321  */
322 int acpi_write_one(struct acpi_ctx *ctx, const struct acpi_writer *entry);
323 
324 /**
325  * acpi_setup_ctx() - Set up a new ACPI context
326  *
327  * This zeros the context and sets up the base and current pointers, ensuring
328  * that they are aligned. Then it writes the acpi_start and acpi_ctx values in
329  * global_data
330  *
331  * @ctx: ACPI context to set up
332  * @start: Start address for ACPI table
333  */
334 void acpi_setup_ctx(struct acpi_ctx *ctx, ulong start);
335 
336 /**
337  * acpi_write_one() - Call a single ACPI writer entry
338  *
339  * This handles aligning the context afterwards, if the entry flags indicate
340  * that.
341  *
342  * @ctx: ACPI context to use
343  * @entry: Entry to call
344  * @return 0 if OK, -ENOENT if this writer produced an empty entry, other -ve
345  * value on error
346  */
347 int acpi_write_one(struct acpi_ctx *ctx, const struct acpi_writer *entry);
348 
349 #endif /* __ACPI__ */
350 
351 #endif
352