xref: /optee_os/core/include/kernel/dt.h (revision 279bfce83bac403aa516516574af9ca403d31290)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * Copyright (c) 2016-2021, Linaro Limited
4  */
5 
6 #ifndef KERNEL_DT_H
7 #define KERNEL_DT_H
8 
9 #include <compiler.h>
10 #include <kernel/interrupt.h>
11 #include <kernel/panic.h>
12 #include <stdint.h>
13 #include <tee_api_types.h>
14 #include <types_ext.h>
15 #include <util.h>
16 
17 /*
18  * Bitfield to reflect status and secure-status values ("okay", "disabled"
19  * or not present)
20  */
21 #define DT_STATUS_DISABLED		U(0)
22 #define DT_STATUS_OK_NSEC		BIT(0)
23 #define DT_STATUS_OK_SEC		BIT(1)
24 
25 #define DT_INFO_INVALID_REG		((paddr_t)-1)
26 #define DT_INFO_INVALID_REG_SIZE	((size_t)-1)
27 #define DT_INFO_INVALID_CLOCK		-1
28 #define DT_INFO_INVALID_RESET		-1
29 #define DT_INFO_INVALID_INTERRUPT	-1
30 
31 /*
32  * @status: Bit mask for DT_STATUS_*
33  * @reg: Device register physical base address or DT_INFO_INVALID_REG
34  * @reg_size: Device register size or DT_INFO_INVALID_REG_SIZE
35  * @clock: Device identifier (positive value) or DT_INFO_INVALID_CLOCK
36  * @reset: Device reset identifier (positive value) or DT_INFO_INVALID_CLOCK
37  * @interrupt: Device interrupt identifier (positive value) or
38  * DT_INFO_INVALID_INTERRUPT
39  * @type: IRQ_TYPE_* value parsed from interrupts properties or IRQ_TYPE_NONE if
40  * not present
41  * @prio: interrupt priority parsed from interrupts properties or 0 if not
42  * present
43  */
44 struct dt_node_info {
45 	unsigned int status;
46 	paddr_t reg;
47 	size_t reg_size;
48 	int clock;
49 	int reset;
50 	int interrupt;
51 	uint32_t type;
52 	uint32_t prio;
53 };
54 
55 #if defined(CFG_DT)
56 
57 /*
58  * DT-aware drivers
59  */
60 
61 struct dt_device_match {
62 	const char *compatible;
63 	const void *compat_data;
64 };
65 
66 enum dt_driver_type {
67 	DT_DRIVER_NOTYPE,
68 	DT_DRIVER_UART,
69 	DT_DRIVER_CLK,
70 };
71 
72 /*
73  * dt_driver_probe_func - Callback probe function for a driver.
74  *
75  * @fdt: FDT base address
76  * @nodeoffset: Offset of the node in the FDT
77  * @compat_data: Data registered for the compatible that probed the device
78  *
79  * Return TEE_SUCCESS on successful probe,
80  *	TEE_ERROR_DEFER_DRIVER_INIT if probe must be deferred
81  *	TEE_ERROR_ITEM_NOT_FOUND when no driver matched node's compatible string
82  *	Any other TEE_ERROR_* compliant code.
83  */
84 typedef TEE_Result (*dt_driver_probe_func)(const void *fdt, int nodeoffset,
85 					   const void *compat_data);
86 
87 /*
88  * Driver instance registered to be probed on compatible node found in the DT.
89  *
90  * @name: Driver name
91  * @type: Drive type
92  * @match_table: Compatible matching identifiers, null terminated
93  * @driver: Driver private reference or NULL
94  * @probe: Probe callback (see dt_driver_probe_func) or NULL
95  */
96 struct dt_driver {
97 	const char *name;
98 	enum dt_driver_type type;
99 	const struct dt_device_match *match_table; /* null-terminated */
100 	const void *driver;
101 	TEE_Result (*probe)(const void *fdt, int node, const void *compat_data);
102 };
103 
104 #define __dt_driver __section(".rodata.dtdrv" __SECTION_FLAGS_RODATA)
105 
106 /*
107  * Find a driver that is suitable for the given DT node, that is, with
108  * a matching "compatible" property.
109  *
110  * @fdt: pointer to the device tree
111  * @offs: node offset
112  */
113 const struct dt_driver *dt_find_compatible_driver(const void *fdt, int offs);
114 
115 const struct dt_driver *__dt_driver_start(void);
116 
117 const struct dt_driver *__dt_driver_end(void);
118 
119 /*
120  * Map a device into secure or non-secure memory and return the base VA and
121  * the mapping size. The mapping is done with type MEM_AREA_IO_SEC or
122  * MEM_AREA_IO_NSEC, depending on the device status.
123  * If the mapping already exists, the function simply returns the @vbase and
124  * @size information.
125  *
126  * @offs is the offset of the node that describes the device in @fdt.
127  * @base receives the base virtual address corresponding to the base physical
128  * address of the "reg" property
129  * @size receives the size of the mapping
130  *
131  * Returns 0 on success or -1 in case of error.
132  */
133 int dt_map_dev(const void *fdt, int offs, vaddr_t *base, size_t *size);
134 
135 /*
136  * Check whether the node at @offs contains the property with propname or not.
137  *
138  * @offs is the offset of the node that describes the device in @fdt.
139  * @propname is the property that need to check
140  *
141  * Returns true on success or false if no propname.
142  */
143 bool dt_have_prop(const void *fdt, int offs, const char *propname);
144 
145 /*
146  * Modify or add "status" property to "disabled"
147  *
148  * @fdt reference to the Device Tree
149  * @node is the node offset to modify
150  *
151  * Returns 0 on success or -1 on failure
152  */
153 int dt_disable_status(void *fdt, int node);
154 
155 /*
156  * Force secure-status = "okay" and status="disabled" for the target node.
157  *
158  * @fdt reference to the Device Tree
159  * @node is the node offset to modify
160  *
161  * Returns 0 on success or -1 on failure
162  */
163 int dt_enable_secure_status(void *fdt, int node);
164 
165 /*
166  * FDT manipulation functions, not provided by <libfdt.h>
167  */
168 
169 /*
170  * Return the base address for the "reg" property of the specified node or
171  * (paddr_t)-1 in case of error
172  */
173 paddr_t _fdt_reg_base_address(const void *fdt, int offs);
174 
175 /*
176  * Return the reg size for the reg property of the specified node or -1 in case
177  * of error
178  */
179 size_t _fdt_reg_size(const void *fdt, int offs);
180 
181 /*
182  * Read the status and secure-status properties into a bitfield.
183  * @status is set to DT_STATUS_DISABLED or a combination of DT_STATUS_OK_NSEC
184  * and DT_STATUS_OK_SEC.
185  */
186 int _fdt_get_status(const void *fdt, int offs);
187 
188 /*
189  * fdt_fill_device_info - Get generic device info from a node
190  *
191  * This function fills the generic information from a given node.
192  * Currently supports a single base register, a single clock,
193  * a single reset ID line and a single interrupt ID.
194  * Default DT_INFO_* macros are used when the relate property is not found.
195  */
196 void _fdt_fill_device_info(const void *fdt, struct dt_node_info *info,
197 			   int node);
198 
199 #else /* !CFG_DT */
200 
201 static inline const struct dt_driver *__dt_driver_start(void)
202 {
203 	return NULL;
204 }
205 
206 static inline const struct dt_driver *__dt_driver_end(void)
207 {
208 	return NULL;
209 }
210 
211 static inline const struct dt_driver *dt_find_compatible_driver(
212 					const void *fdt __unused,
213 					int offs __unused)
214 {
215 	return NULL;
216 }
217 
218 static inline int dt_map_dev(const void *fdt __unused, int offs __unused,
219 			     vaddr_t *vbase __unused, size_t *size __unused)
220 {
221 	return -1;
222 }
223 
224 static inline paddr_t _fdt_reg_base_address(const void *fdt __unused,
225 					    int offs __unused)
226 {
227 	return (paddr_t)-1;
228 }
229 
230 static inline size_t _fdt_reg_size(const void *fdt __unused,
231 				   int offs __unused)
232 {
233 	return (size_t)-1;
234 }
235 
236 static inline int _fdt_get_status(const void *fdt __unused, int offs __unused)
237 {
238 	return -1;
239 }
240 
241 __noreturn
242 static inline void _fdt_fill_device_info(const void *fdt __unused,
243 					 struct dt_node_info *info __unused,
244 					 int node __unused)
245 {
246 	panic();
247 }
248 #endif /* !CFG_DT */
249 
250 #define for_each_dt_driver(drv) \
251 	for (drv = __dt_driver_start(); drv < __dt_driver_end(); drv++)
252 
253 #endif /* KERNEL_DT_H */
254