1 /* 2 * Copyright (c) 2013-2015, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #ifndef __BAKERY_LOCK_H__ 8 #define __BAKERY_LOCK_H__ 9 10 #include <platform_def.h> 11 12 #define BAKERY_LOCK_MAX_CPUS PLATFORM_CORE_COUNT 13 14 #ifndef __ASSEMBLY__ 15 #include <stdint.h> 16 17 /***************************************************************************** 18 * Internal helper macros used by the bakery lock implementation. 19 ****************************************************************************/ 20 /* Convert a ticket to priority */ 21 #define PRIORITY(t, pos) (((t) << 8) | (pos)) 22 23 #define CHOOSING_TICKET 0x1 24 #define CHOSEN_TICKET 0x0 25 26 #define bakery_is_choosing(info) (info & 0x1) 27 #define bakery_ticket_number(info) ((info >> 1) & 0x7FFF) 28 #define make_bakery_data(choosing, number) \ 29 (((choosing & 0x1) | (number << 1)) & 0xFFFF) 30 31 /***************************************************************************** 32 * External bakery lock interface. 33 ****************************************************************************/ 34 #if USE_COHERENT_MEM 35 /* 36 * Bakery locks are stored in coherent memory 37 * 38 * Each lock's data is contiguous and fully allocated by the compiler 39 */ 40 41 typedef struct bakery_lock { 42 /* 43 * The lock_data is a bit-field of 2 members: 44 * Bit[0] : choosing. This field is set when the CPU is 45 * choosing its bakery number. 46 * Bits[1 - 15] : number. This is the bakery number allocated. 47 */ 48 volatile uint16_t lock_data[BAKERY_LOCK_MAX_CPUS]; 49 } bakery_lock_t; 50 51 #else 52 /* 53 * Bakery locks are stored in normal .bss memory 54 * 55 * Each lock's data is spread across multiple cache lines, one per CPU, 56 * but multiple locks can share the same cache line. 57 * The compiler will allocate enough memory for one CPU's bakery locks, 58 * the remaining cache lines are allocated by the linker script 59 */ 60 61 typedef struct bakery_info { 62 /* 63 * The lock_data is a bit-field of 2 members: 64 * Bit[0] : choosing. This field is set when the CPU is 65 * choosing its bakery number. 66 * Bits[1 - 15] : number. This is the bakery number allocated. 67 */ 68 volatile uint16_t lock_data; 69 } bakery_info_t; 70 71 typedef bakery_info_t bakery_lock_t; 72 73 #endif /* __USE_COHERENT_MEM__ */ 74 75 static inline void bakery_lock_init(bakery_lock_t *bakery) {} 76 void bakery_lock_get(bakery_lock_t *bakery); 77 void bakery_lock_release(bakery_lock_t *bakery); 78 79 #define DEFINE_BAKERY_LOCK(_name) bakery_lock_t _name __section("bakery_lock") 80 81 #define DECLARE_BAKERY_LOCK(_name) extern bakery_lock_t _name 82 83 84 #endif /* __ASSEMBLY__ */ 85 #endif /* __BAKERY_LOCK_H__ */ 86
