xref: /optee_os/core/include/kernel/dt.h (revision 61bdedea9452abc1ec1582075fdd9cb9f81953a6)
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 <scattered_array.h>
13 #include <stdint.h>
14 #include <tee_api_types.h>
15 #include <types_ext.h>
16 #include <util.h>
17 
18 /*
19  * Bitfield to reflect status and secure-status values ("okay", "disabled"
20  * or not present)
21  */
22 #define DT_STATUS_DISABLED		U(0)
23 #define DT_STATUS_OK_NSEC		BIT(0)
24 #define DT_STATUS_OK_SEC		BIT(1)
25 
26 #define DT_INFO_INVALID_REG		((paddr_t)-1)
27 #define DT_INFO_INVALID_REG_SIZE	((size_t)-1)
28 #define DT_INFO_INVALID_CLOCK		-1
29 #define DT_INFO_INVALID_RESET		-1
30 #define DT_INFO_INVALID_INTERRUPT	-1
31 
32 /*
33  * @status: Bit mask for DT_STATUS_*
34  * @reg: Device register physical base address or DT_INFO_INVALID_REG
35  * @reg_size: Device register size or DT_INFO_INVALID_REG_SIZE
36  * @clock: Device identifier (positive value) or DT_INFO_INVALID_CLOCK
37  * @reset: Device reset identifier (positive value) or DT_INFO_INVALID_CLOCK
38  * @interrupt: Device interrupt identifier (positive value) or
39  * DT_INFO_INVALID_INTERRUPT
40  * @type: IRQ_TYPE_* value parsed from interrupts properties or IRQ_TYPE_NONE if
41  * not present
42  * @prio: interrupt priority parsed from interrupts properties or 0 if not
43  * present
44  */
45 struct dt_node_info {
46 	unsigned int status;
47 	paddr_t reg;
48 	size_t reg_size;
49 	int clock;
50 	int reset;
51 	int interrupt;
52 	uint32_t type;
53 	uint32_t prio;
54 };
55 
56 /*
57  * DT-aware drivers
58  */
59 
60 struct dt_device_match {
61 	const char *compatible;
62 	const void *compat_data;
63 };
64 
65 enum dt_driver_type {
66 	DT_DRIVER_NOTYPE,
67 	DT_DRIVER_UART,
68 	DT_DRIVER_CLK,
69 };
70 
71 /*
72  * dt_driver_probe_func - Callback probe function for a driver.
73  *
74  * @fdt: FDT base address
75  * @nodeoffset: Offset of the node in the FDT
76  * @compat_data: Data registered for the compatible that probed the device
77  *
78  * Return TEE_SUCCESS on successful probe,
79  *	TEE_ERROR_DEFER_DRIVER_INIT if probe must be deferred
80  *	TEE_ERROR_ITEM_NOT_FOUND when no driver matched node's compatible string
81  *	Any other TEE_ERROR_* compliant code.
82  */
83 typedef TEE_Result (*dt_driver_probe_func)(const void *fdt, int nodeoffset,
84 					   const void *compat_data);
85 
86 #if defined(CFG_DT)
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 DEFINE_DT_DRIVER(name) \
105 		SCATTERED_ARRAY_DEFINE_ITEM(dt_drivers, struct dt_driver)
106 
107 /*
108  * Find a driver that is suitable for the given DT node, that is, with
109  * a matching "compatible" property.
110  *
111  * @fdt: pointer to the device tree
112  * @offs: node offset
113  */
114 const struct dt_driver *dt_find_compatible_driver(const void *fdt, int offs);
115 
116 /*
117  * Map a device into secure or non-secure memory and return the base VA and
118  * the mapping size. The mapping is done with type MEM_AREA_IO_SEC or
119  * MEM_AREA_IO_NSEC, depending on the device status.
120  * If the mapping already exists, the function simply returns the @vbase and
121  * @size information.
122  *
123  * @offs is the offset of the node that describes the device in @fdt.
124  * @base receives the base virtual address corresponding to the base physical
125  * address of the "reg" property
126  * @size receives the size of the mapping
127  *
128  * Returns 0 on success or -1 in case of error.
129  */
130 int dt_map_dev(const void *fdt, int offs, vaddr_t *base, size_t *size);
131 
132 /*
133  * Check whether the node at @offs contains the property with propname or not.
134  *
135  * @offs is the offset of the node that describes the device in @fdt.
136  * @propname is the property that need to check
137  *
138  * Returns true on success or false if no propname.
139  */
140 bool dt_have_prop(const void *fdt, int offs, const char *propname);
141 
142 /*
143  * Modify or add "status" property to "disabled"
144  *
145  * @fdt reference to the Device Tree
146  * @node is the node offset to modify
147  *
148  * Returns 0 on success or -1 on failure
149  */
150 int dt_disable_status(void *fdt, int node);
151 
152 /*
153  * Force secure-status = "okay" and status="disabled" for the target node.
154  *
155  * @fdt reference to the Device Tree
156  * @node is the node offset to modify
157  *
158  * Returns 0 on success or -1 on failure
159  */
160 int dt_enable_secure_status(void *fdt, int node);
161 
162 /*
163  * FDT manipulation functions, not provided by <libfdt.h>
164  */
165 
166 /*
167  * Return the base address for the "reg" property of the specified node or
168  * (paddr_t)-1 in case of error
169  */
170 paddr_t _fdt_reg_base_address(const void *fdt, int offs);
171 
172 /*
173  * Return the reg size for the reg property of the specified node or -1 in case
174  * of error
175  */
176 size_t _fdt_reg_size(const void *fdt, int offs);
177 
178 /*
179  * Read the status and secure-status properties into a bitfield.
180  * Return -1 on failure, DT_STATUS_DISABLED if the node is disabled,
181  * otherwise return a combination of DT_STATUS_OK_NSEC and DT_STATUS_OK_SEC.
182  */
183 int _fdt_get_status(const void *fdt, int offs);
184 
185 /*
186  * fdt_fill_device_info - Get generic device info from a node
187  *
188  * This function fills the generic information from a given node.
189  * Currently supports a single base register, a single clock,
190  * a single reset ID line and a single interrupt ID.
191  * Default DT_INFO_* macros are used when the relate property is not found.
192  */
193 void _fdt_fill_device_info(const void *fdt, struct dt_node_info *info,
194 			   int node);
195 
196 #else /* !CFG_DT */
197 
198 static inline const struct dt_driver *dt_find_compatible_driver(
199 					const void *fdt __unused,
200 					int offs __unused)
201 {
202 	return NULL;
203 }
204 
205 static inline int dt_map_dev(const void *fdt __unused, int offs __unused,
206 			     vaddr_t *vbase __unused, size_t *size __unused)
207 {
208 	return -1;
209 }
210 
211 static inline paddr_t _fdt_reg_base_address(const void *fdt __unused,
212 					    int offs __unused)
213 {
214 	return (paddr_t)-1;
215 }
216 
217 static inline size_t _fdt_reg_size(const void *fdt __unused,
218 				   int offs __unused)
219 {
220 	return (size_t)-1;
221 }
222 
223 static inline int _fdt_get_status(const void *fdt __unused, int offs __unused)
224 {
225 	return -1;
226 }
227 
228 __noreturn
229 static inline void _fdt_fill_device_info(const void *fdt __unused,
230 					 struct dt_node_info *info __unused,
231 					 int node __unused)
232 {
233 	panic();
234 }
235 #endif /* !CFG_DT */
236 
237 #define for_each_dt_driver(drv) \
238 	for (drv = SCATTERED_ARRAY_BEGIN(dt_drivers, struct dt_driver); \
239 	     drv < SCATTERED_ARRAY_END(dt_drivers, struct dt_driver); \
240 	     drv++)
241 
242 #endif /* KERNEL_DT_H */
243