xref: /rk3399_ARM-atf/include/bl31/ehf.h (revision 091f39675a98ee9e22ed78f52e239880bedf8911)
1 /*
2  * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #ifndef EHF_H
8 #define EHF_H
9 
10 #ifndef __ASSEMBLY__
11 
12 #include <stdint.h>
13 #include <utils_def.h>
14 
15 /* Valid priorities set bit 0 of the priority handler. */
16 #define EHF_PRI_VALID_	(((uintptr_t) 1) << 0)
17 
18 /* Marker for no handler registered for a valid priority */
19 #define EHF_NO_HANDLER_	(0U | EHF_PRI_VALID_)
20 
21 /* Extract the specified number of top bits from 7 lower bits of priority */
22 #define EHF_PRI_TO_IDX(pri, plat_bits) \
23 	((((unsigned) (pri)) & 0x7fu) >> (7u - (plat_bits)))
24 
25 /* Install exception priority descriptor at a suitable index */
26 #define EHF_PRI_DESC(plat_bits, priority) \
27 	[EHF_PRI_TO_IDX(priority, plat_bits)] = { \
28 		.ehf_handler = EHF_NO_HANDLER_, \
29 	}
30 
31 /* Macro for platforms to regiter its exception priorities */
32 #define EHF_REGISTER_PRIORITIES(priorities, num, bits) \
33 	const ehf_priorities_t exception_data = { \
34 		.num_priorities = (num), \
35 		.ehf_priorities = (priorities), \
36 		.pri_bits = (bits), \
37 	}
38 
39 /*
40  * Priority stack, managed as a bitmap.
41  *
42  * Currently only supports 32 priority levels, allowing platforms to use up to 5
43  * top bits of priority. But the type can be changed to uint64_t should need
44  * arise to support 64 priority levels, allowing platforms to use up to 6 top
45  * bits of priority.
46  */
47 typedef uint32_t ehf_pri_bits_t;
48 
49 /*
50  * Per-PE exception data. The data for each PE is kept as a per-CPU data field.
51  * See cpu_data.h.
52  */
53 typedef struct {
54 	ehf_pri_bits_t active_pri_bits;
55 
56 	/* Priority mask value before any priority levels were active */
57 	uint8_t init_pri_mask;
58 
59 	/* Non-secure priority mask value stashed during Secure execution */
60 	uint8_t ns_pri_mask;
61 } __aligned(sizeof(uint64_t)) pe_exc_data_t;
62 
63 typedef int (*ehf_handler_t)(uint32_t intr_raw, uint32_t flags, void *handle,
64 		void *cookie);
65 
66 typedef struct ehf_pri_desc {
67 	/*
68 	 * 4-byte-aligned exception handler. Bit 0 indicates the corresponding
69 	 * priority level is valid. This is effectively of ehf_handler_t type,
70 	 * but left as uintptr_t in order to make pointer arithmetic convenient.
71 	 */
72 	uintptr_t ehf_handler;
73 } ehf_pri_desc_t;
74 
75 typedef struct ehf_priority_type {
76 	ehf_pri_desc_t *ehf_priorities;
77 	unsigned int num_priorities;
78 	unsigned int pri_bits;
79 } ehf_priorities_t;
80 
81 void ehf_init(void);
82 void ehf_activate_priority(unsigned int priority);
83 void ehf_deactivate_priority(unsigned int priority);
84 void ehf_register_priority_handler(unsigned int pri, ehf_handler_t handler);
85 void ehf_allow_ns_preemption(uint64_t preempt_ret_code);
86 unsigned int ehf_is_ns_preemption_allowed(void);
87 
88 #endif /* __ASSEMBLY__ */
89 
90 #endif /* EHF_H */
91