xref: /optee_os/core/include/kernel/dt.h (revision 45f25897f4bcac14dc13e2adee7f1f96f117fcde)
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 /*
56  * DT-aware drivers
57  */
58 
59 struct dt_device_match {
60 	const char *compatible;
61 	const void *compat_data;
62 };
63 
64 enum dt_driver_type {
65 	DT_DRIVER_NOTYPE,
66 	DT_DRIVER_UART,
67 	DT_DRIVER_CLK,
68 };
69 
70 /*
71  * dt_driver_probe_func - Callback probe function for a driver.
72  *
73  * @fdt: FDT base address
74  * @nodeoffset: Offset of the node in the FDT
75  * @compat_data: Data registered for the compatible that probed the device
76  *
77  * Return TEE_SUCCESS on successful probe,
78  *	TEE_ERROR_DEFER_DRIVER_INIT if probe must be deferred
79  *	TEE_ERROR_ITEM_NOT_FOUND when no driver matched node's compatible string
80  *	Any other TEE_ERROR_* compliant code.
81  */
82 typedef TEE_Result (*dt_driver_probe_func)(const void *fdt, int nodeoffset,
83 					   const void *compat_data);
84 
85 #if defined(CFG_DT)
86 /*
87  * Driver instance registered to be probed on compatible node found in the DT.
88  *
89  * @name: Driver name
90  * @type: Drive type
91  * @match_table: Compatible matching identifiers, null terminated
92  * @driver: Driver private reference or NULL
93  * @probe: Probe callback (see dt_driver_probe_func) or NULL
94  */
95 struct dt_driver {
96 	const char *name;
97 	enum dt_driver_type type;
98 	const struct dt_device_match *match_table; /* null-terminated */
99 	const void *driver;
100 	TEE_Result (*probe)(const void *fdt, int node, const void *compat_data);
101 };
102 
103 #define __dt_driver __section(".rodata.dtdrv" __SECTION_FLAGS_RODATA)
104 
105 /*
106  * Find a driver that is suitable for the given DT node, that is, with
107  * a matching "compatible" property.
108  *
109  * @fdt: pointer to the device tree
110  * @offs: node offset
111  */
112 const struct dt_driver *dt_find_compatible_driver(const void *fdt, int offs);
113 
114 const struct dt_driver *__dt_driver_start(void);
115 
116 const struct dt_driver *__dt_driver_end(void);
117 
118 /*
119  * Map a device into secure or non-secure memory and return the base VA and
120  * the mapping size. The mapping is done with type MEM_AREA_IO_SEC or
121  * MEM_AREA_IO_NSEC, depending on the device status.
122  * If the mapping already exists, the function simply returns the @vbase and
123  * @size information.
124  *
125  * @offs is the offset of the node that describes the device in @fdt.
126  * @base receives the base virtual address corresponding to the base physical
127  * address of the "reg" property
128  * @size receives the size of the mapping
129  *
130  * Returns 0 on success or -1 in case of error.
131  */
132 int dt_map_dev(const void *fdt, int offs, vaddr_t *base, size_t *size);
133 
134 /*
135  * Check whether the node at @offs contains the property with propname or not.
136  *
137  * @offs is the offset of the node that describes the device in @fdt.
138  * @propname is the property that need to check
139  *
140  * Returns true on success or false if no propname.
141  */
142 bool dt_have_prop(const void *fdt, int offs, const char *propname);
143 
144 /*
145  * Modify or add "status" property to "disabled"
146  *
147  * @fdt reference to the Device Tree
148  * @node is the node offset to modify
149  *
150  * Returns 0 on success or -1 on failure
151  */
152 int dt_disable_status(void *fdt, int node);
153 
154 /*
155  * Force secure-status = "okay" and status="disabled" for the target node.
156  *
157  * @fdt reference to the Device Tree
158  * @node is the node offset to modify
159  *
160  * Returns 0 on success or -1 on failure
161  */
162 int dt_enable_secure_status(void *fdt, int node);
163 
164 /*
165  * FDT manipulation functions, not provided by <libfdt.h>
166  */
167 
168 /*
169  * Return the base address for the "reg" property of the specified node or
170  * (paddr_t)-1 in case of error
171  */
172 paddr_t _fdt_reg_base_address(const void *fdt, int offs);
173 
174 /*
175  * Return the reg size for the reg property of the specified node or -1 in case
176  * of error
177  */
178 size_t _fdt_reg_size(const void *fdt, int offs);
179 
180 /*
181  * Read the status and secure-status properties into a bitfield.
182  * Return -1 on failure, DT_STATUS_DISABLED if the node is disabled,
183  * otherwise return a combination of DT_STATUS_OK_NSEC and DT_STATUS_OK_SEC.
184  */
185 int _fdt_get_status(const void *fdt, int offs);
186 
187 /*
188  * fdt_fill_device_info - Get generic device info from a node
189  *
190  * This function fills the generic information from a given node.
191  * Currently supports a single base register, a single clock,
192  * a single reset ID line and a single interrupt ID.
193  * Default DT_INFO_* macros are used when the relate property is not found.
194  */
195 void _fdt_fill_device_info(const void *fdt, struct dt_node_info *info,
196 			   int node);
197 
198 #else /* !CFG_DT */
199 
200 static inline const struct dt_driver *__dt_driver_start(void)
201 {
202 	return NULL;
203 }
204 
205 static inline const struct dt_driver *__dt_driver_end(void)
206 {
207 	return NULL;
208 }
209 
210 static inline const struct dt_driver *dt_find_compatible_driver(
211 					const void *fdt __unused,
212 					int offs __unused)
213 {
214 	return NULL;
215 }
216 
217 static inline int dt_map_dev(const void *fdt __unused, int offs __unused,
218 			     vaddr_t *vbase __unused, size_t *size __unused)
219 {
220 	return -1;
221 }
222 
223 static inline paddr_t _fdt_reg_base_address(const void *fdt __unused,
224 					    int offs __unused)
225 {
226 	return (paddr_t)-1;
227 }
228 
229 static inline size_t _fdt_reg_size(const void *fdt __unused,
230 				   int offs __unused)
231 {
232 	return (size_t)-1;
233 }
234 
235 static inline int _fdt_get_status(const void *fdt __unused, int offs __unused)
236 {
237 	return -1;
238 }
239 
240 __noreturn
241 static inline void _fdt_fill_device_info(const void *fdt __unused,
242 					 struct dt_node_info *info __unused,
243 					 int node __unused)
244 {
245 	panic();
246 }
247 #endif /* !CFG_DT */
248 
249 #define for_each_dt_driver(drv) \
250 	for (drv = __dt_driver_start(); drv < __dt_driver_end(); drv++)
251 
252 #endif /* KERNEL_DT_H */
253