1 /**************************************************************************//**
2 * @file os_tick_ptim.c
3 * @brief CMSIS OS Tick implementation for Private Timer
4 * @version V1.0.2
5 * @date 02. March 2018
6 ******************************************************************************/
7 /*
8 * Copyright (c) 2017-2018 Arm Limited. All rights reserved.
9 *
10 * SPDX-License-Identifier: Apache-2.0
11 *
12 * Licensed under the Apache License, Version 2.0 (the License); you may
13 * not use this file except in compliance with the License.
14 * You may obtain a copy of the License at
15 *
16 * www.apache.org/licenses/LICENSE-2.0
17 *
18 * Unless required by applicable law or agreed to in writing, software
19 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
20 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
21 * See the License for the specific language governing permissions and
22 * limitations under the License.
23 */
24
25 #include "RTE_Components.h"
26 #include CMSIS_device_header
27
28 #if defined(PTIM)
29
30 #include "os_tick.h"
31 #include "irq_ctrl.h"
32
33 #ifndef PTIM_IRQ_PRIORITY
34 #define PTIM_IRQ_PRIORITY 0xFFU
35 #endif
36
37 static uint8_t PTIM_PendIRQ; // Timer interrupt pending flag
38
39 // Setup OS Tick.
OS_Tick_Setup(uint32_t freq,IRQHandler_t handler)40 int32_t OS_Tick_Setup (uint32_t freq, IRQHandler_t handler) {
41 uint32_t load;
42 uint32_t prio;
43 uint32_t bits;
44
45 if (freq == 0U) {
46 return (-1);
47 }
48
49 PTIM_PendIRQ = 0U;
50
51 // Private Timer runs with the system frequency
52 load = (SystemCoreClock / freq) - 1U;
53
54 // Disable Private Timer and set load value
55 PTIM_SetControl (0U);
56 PTIM_SetLoadValue (load);
57
58 // Disable corresponding IRQ
59 IRQ_Disable (PrivTimer_IRQn);
60 IRQ_ClearPending(PrivTimer_IRQn);
61
62 // Determine number of implemented priority bits
63 IRQ_SetPriority (PrivTimer_IRQn, 0xFFU);
64
65 prio = IRQ_GetPriority (PrivTimer_IRQn);
66
67 // At least bits [7:4] must be implemented
68 if ((prio & 0xF0U) == 0U) {
69 return (-1);
70 }
71
72 for (bits = 0; bits < 4; bits++) {
73 if ((prio & 0x01) != 0) {
74 break;
75 }
76 prio >>= 1;
77 }
78
79 // Adjust configured priority to the number of implemented priority bits
80 prio = (PTIM_IRQ_PRIORITY << bits) & 0xFFUL;
81
82 // Set Private Timer interrupt priority
83 IRQ_SetPriority(PrivTimer_IRQn, prio-1U);
84
85 // Set edge-triggered IRQ
86 IRQ_SetMode(PrivTimer_IRQn, IRQ_MODE_TRIG_EDGE);
87
88 // Register tick interrupt handler function
89 IRQ_SetHandler(PrivTimer_IRQn, handler);
90
91 // Enable corresponding interrupt
92 IRQ_Enable (PrivTimer_IRQn);
93
94 // Set bits: IRQ enable and Auto reload
95 PTIM_SetControl (0x06U);
96
97 return (0);
98 }
99
100 /// Enable OS Tick.
OS_Tick_Enable(void)101 void OS_Tick_Enable (void) {
102 uint32_t ctrl;
103
104 // Set pending interrupt if flag set
105 if (PTIM_PendIRQ != 0U) {
106 PTIM_PendIRQ = 0U;
107 IRQ_SetPending (PrivTimer_IRQn);
108 }
109
110 // Start the Private Timer
111 ctrl = PTIM_GetControl();
112 // Set bit: Timer enable
113 ctrl |= 1U;
114 PTIM_SetControl (ctrl);
115 }
116
117 /// Disable OS Tick.
OS_Tick_Disable(void)118 void OS_Tick_Disable (void) {
119 uint32_t ctrl;
120
121 // Stop the Private Timer
122 ctrl = PTIM_GetControl();
123 // Clear bit: Timer enable
124 ctrl &= ~1U;
125 PTIM_SetControl (ctrl);
126
127 // Remember pending interrupt flag
128 if (IRQ_GetPending(PrivTimer_IRQn) != 0) {
129 IRQ_ClearPending (PrivTimer_IRQn);
130 PTIM_PendIRQ = 1U;
131 }
132 }
133
134 // Acknowledge OS Tick IRQ.
OS_Tick_AcknowledgeIRQ(void)135 void OS_Tick_AcknowledgeIRQ (void) {
136 PTIM_ClearEventFlag();
137 }
138
139 // Get OS Tick IRQ number.
OS_Tick_GetIRQn(void)140 int32_t OS_Tick_GetIRQn (void) {
141 return (PrivTimer_IRQn);
142 }
143
144 // Get OS Tick clock.
OS_Tick_GetClock(void)145 uint32_t OS_Tick_GetClock (void) {
146 return (SystemCoreClock);
147 }
148
149 // Get OS Tick interval.
OS_Tick_GetInterval(void)150 uint32_t OS_Tick_GetInterval (void) {
151 return (PTIM_GetLoadValue() + 1U);
152 }
153
154 // Get OS Tick count value.
OS_Tick_GetCount(void)155 uint32_t OS_Tick_GetCount (void) {
156 uint32_t load = PTIM_GetLoadValue();
157 return (load - PTIM_GetCurrentValue());
158 }
159
160 // Get OS Tick overflow status.
OS_Tick_GetOverflow(void)161 uint32_t OS_Tick_GetOverflow (void) {
162 return (PTIM->ISR & 1);
163 }
164
165 #endif // PTIM
166
