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 __ASSEMBLER__ 11 12 #include <cdefs.h> 13 #include <stdint.h> 14 15 #include <lib/utils_def.h> 16 17 /* Valid priorities set bit 0 of the priority handler. */ 18 #define EHF_PRI_VALID_ BIT(0) 19 20 /* Marker for no handler registered for a valid priority */ 21 #define EHF_NO_HANDLER_ (0U | EHF_PRI_VALID_) 22 23 /* Extract the specified number of top bits from 7 lower bits of priority */ 24 #define EHF_PRI_TO_IDX(pri, plat_bits) \ 25 ((((unsigned) (pri)) & 0x7fu) >> (7u - (plat_bits))) 26 27 /* Install exception priority descriptor at a suitable index */ 28 #define EHF_PRI_DESC(plat_bits, priority) \ 29 [EHF_PRI_TO_IDX(priority, plat_bits)] = { \ 30 .ehf_handler = EHF_NO_HANDLER_, \ 31 } 32 33 /* Macro for platforms to regiter its exception priorities */ 34 #define EHF_REGISTER_PRIORITIES(priorities, num, bits) \ 35 const ehf_priorities_t exception_data = { \ 36 .num_priorities = (num), \ 37 .ehf_priorities = (priorities), \ 38 .pri_bits = (bits), \ 39 } 40 41 /* 42 * Priority stack, managed as a bitmap. 43 * 44 * Currently only supports 32 priority levels, allowing platforms to use up to 5 45 * top bits of priority. But the type can be changed to uint64_t should need 46 * arise to support 64 priority levels, allowing platforms to use up to 6 top 47 * bits of priority. 48 */ 49 typedef uint32_t ehf_pri_bits_t; 50 51 /* 52 * Per-PE exception data. The data for each PE is kept as a per-CPU data field. 53 * See cpu_data.h. 54 */ 55 typedef struct { 56 ehf_pri_bits_t active_pri_bits; 57 58 /* Priority mask value before any priority levels were active */ 59 uint8_t init_pri_mask; 60 61 /* Non-secure priority mask value stashed during Secure execution */ 62 uint8_t ns_pri_mask; 63 } __aligned(sizeof(uint64_t)) pe_exc_data_t; 64 65 typedef int (*ehf_handler_t)(uint32_t intr_raw, uint32_t flags, void *handle, 66 void *cookie); 67 68 typedef struct ehf_pri_desc { 69 /* 70 * 4-byte-aligned exception handler. Bit 0 indicates the corresponding 71 * priority level is valid. This is effectively of ehf_handler_t type, 72 * but left as uintptr_t in order to make pointer arithmetic convenient. 73 */ 74 uintptr_t ehf_handler; 75 } ehf_pri_desc_t; 76 77 typedef struct ehf_priority_type { 78 ehf_pri_desc_t *ehf_priorities; 79 unsigned int num_priorities; 80 unsigned int pri_bits; 81 } ehf_priorities_t; 82 83 void ehf_init(void); 84 void ehf_activate_priority(unsigned int priority); 85 void ehf_deactivate_priority(unsigned int priority); 86 void ehf_register_priority_handler(unsigned int pri, ehf_handler_t handler); 87 void ehf_allow_ns_preemption(uint64_t preempt_ret_code); 88 unsigned int ehf_is_ns_preemption_allowed(void); 89 90 #endif /* __ASSEMBLER__ */ 91 92 #endif /* EHF_H */ 93