1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef __ISR_H
18#define __ISR_H
19
20#include <stdbool.h>
21#include <stdint.h>
22
23#include <cpu.h>
24#include <list.h>
25#include <util.h>
26#include <seos.h>
27
28struct ChainedInterrupt {
29    link_t isrs;
30
31    void (*const enable)(struct ChainedInterrupt *);
32    void (*const disable)(struct ChainedInterrupt *);
33};
34
35struct ChainedIsr {
36    link_t node;
37
38    uint32_t maxLatencyNs;
39
40    bool (*func)(struct ChainedIsr *);
41    uint16_t tid;
42};
43
44static inline void chainIsr(struct ChainedInterrupt *interrupt, struct ChainedIsr *isr)
45{
46    interrupt->disable(interrupt);
47    isr->tid = osGetCurrentTid();
48    list_add_tail(&interrupt->isrs, &isr->node);
49    interrupt->enable(interrupt);
50}
51
52static inline void unchainIsr(struct ChainedInterrupt *interrupt, struct ChainedIsr *isr)
53{
54    interrupt->disable(interrupt);
55    isr->tid = 0;
56    list_delete(&isr->node);
57    if (!list_is_empty(&interrupt->isrs))
58        interrupt->enable(interrupt);
59}
60
61static inline bool dispatchIsr(struct ChainedInterrupt *interrupt)
62{
63    struct link_t *cur, *tmp;
64    bool handled = false;
65    uint16_t oldTid = osGetCurrentTid();
66
67    list_iterate(&interrupt->isrs, cur, tmp) {
68        struct ChainedIsr *curIsr = container_of(cur, struct ChainedIsr, node);
69        osSetCurrentTid(curIsr->tid);
70        handled = curIsr->func(curIsr);
71        if (handled)
72            break;
73    }
74    osSetCurrentTid(oldTid);
75
76    return handled;
77}
78
79static inline int unchainIsrAll(struct ChainedInterrupt *interrupt, uint32_t tid)
80{
81    int count = 0;
82    struct link_t *cur, *tmp;
83
84    list_iterate(&interrupt->isrs, cur, tmp) {
85        struct ChainedIsr *curIsr = container_of(cur, struct ChainedIsr, node);
86        if (curIsr->tid == tid) {
87            unchainIsr(interrupt, curIsr);
88            count++;
89        }
90    }
91
92    return count;
93}
94
95static inline uint32_t maxLatencyIsr(struct ChainedInterrupt *interrupt)
96{
97    struct link_t *cur, *tmp;
98    uint32_t latency = 0;
99
100    list_iterate(&interrupt->isrs, cur, tmp) {
101        struct ChainedIsr *curIsr = container_of(cur, struct ChainedIsr, node);
102        if (!latency || (curIsr->maxLatencyNs && curIsr->maxLatencyNs < latency))
103            latency = curIsr->maxLatencyNs;
104    }
105
106    return latency;
107}
108
109#endif /* __ISR_H */
110