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