Antonio Nino Diaz | 07c13a3 | 2018-11-08 09:21:48 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2018, Arm Limited. All rights reserved. |
| 3 | * |
| 4 | * SPDX-License-Identifier: BSD-3-Clause |
| 5 | */ |
| 6 | |
| 7 | #include <assert.h> |
| 8 | #include <errno.h> |
| 9 | #include <stdint.h> |
| 10 | #include <string.h> |
| 11 | |
| 12 | #include "sprt_queue.h" |
| 13 | |
| 14 | void sprt_queue_init(void *queue_base, uint32_t entry_num, uint32_t entry_size) |
| 15 | { |
| 16 | assert(queue_base != NULL); |
| 17 | assert(entry_size > 0U); |
| 18 | assert(entry_num > 0U); |
| 19 | |
| 20 | struct sprt_queue *queue = (struct sprt_queue *)queue_base; |
| 21 | |
| 22 | queue->entry_num = entry_num; |
| 23 | queue->entry_size = entry_size; |
| 24 | queue->idx_write = 0U; |
| 25 | queue->idx_read = 0U; |
| 26 | |
| 27 | memset(queue->data, 0, entry_num * entry_size); |
| 28 | } |
| 29 | |
| 30 | int sprt_queue_is_empty(void *queue_base) |
| 31 | { |
| 32 | assert(queue_base != NULL); |
| 33 | |
| 34 | struct sprt_queue *queue = (struct sprt_queue *)queue_base; |
| 35 | |
| 36 | return (queue->idx_write == queue->idx_read); |
| 37 | } |
| 38 | |
| 39 | int sprt_queue_is_full(void *queue_base) |
| 40 | { |
| 41 | assert(queue_base != NULL); |
| 42 | |
| 43 | struct sprt_queue *queue = (struct sprt_queue *)queue_base; |
| 44 | |
| 45 | uint32_t idx_next_write = (queue->idx_write + 1) % queue->entry_num; |
| 46 | |
| 47 | return (idx_next_write == queue->idx_read); |
| 48 | } |
| 49 | |
| 50 | int sprt_queue_push(void *queue_base, const void *entry) |
| 51 | { |
| 52 | assert(entry != NULL); |
| 53 | assert(queue_base != NULL); |
| 54 | |
| 55 | if (sprt_queue_is_full(queue_base) != 0) { |
| 56 | return -ENOMEM; |
| 57 | } |
| 58 | |
| 59 | struct sprt_queue *queue = (struct sprt_queue *)queue_base; |
| 60 | |
| 61 | uint8_t *dst_entry = &queue->data[queue->entry_size * queue->idx_write]; |
| 62 | |
| 63 | memcpy(dst_entry, entry, queue->entry_size); |
| 64 | |
| 65 | /* |
| 66 | * Make sure that the message data is visible before increasing the |
| 67 | * counter of available messages. |
| 68 | */ |
| 69 | __asm__ volatile("dmb st" ::: "memory"); |
| 70 | |
| 71 | queue->idx_write = (queue->idx_write + 1) % queue->entry_num; |
| 72 | |
| 73 | __asm__ volatile("dmb st" ::: "memory"); |
| 74 | |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | int sprt_queue_pop(void *queue_base, void *entry) |
| 79 | { |
| 80 | assert(entry != NULL); |
| 81 | assert(queue_base != NULL); |
| 82 | |
| 83 | if (sprt_queue_is_empty(queue_base) != 0) { |
| 84 | return -ENOENT; |
| 85 | } |
| 86 | |
| 87 | struct sprt_queue *queue = (struct sprt_queue *)queue_base; |
| 88 | |
| 89 | uint8_t *src_entry = &queue->data[queue->entry_size * queue->idx_read]; |
| 90 | |
| 91 | memcpy(entry, src_entry, queue->entry_size); |
| 92 | |
| 93 | /* |
| 94 | * Make sure that the message data is visible before increasing the |
| 95 | * counter of read messages. |
| 96 | */ |
| 97 | __asm__ volatile("dmb st" ::: "memory"); |
| 98 | |
| 99 | queue->idx_read = (queue->idx_read + 1) % queue->entry_num; |
| 100 | |
| 101 | __asm__ volatile("dmb st" ::: "memory"); |
| 102 | |
| 103 | return 0; |
| 104 | } |