1 |
572 |
jeremybenn |
/*
|
2 |
|
|
FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.
|
3 |
|
|
|
4 |
|
|
***************************************************************************
|
5 |
|
|
* *
|
6 |
|
|
* If you are: *
|
7 |
|
|
* *
|
8 |
|
|
* + New to FreeRTOS, *
|
9 |
|
|
* + Wanting to learn FreeRTOS or multitasking in general quickly *
|
10 |
|
|
* + Looking for basic training, *
|
11 |
|
|
* + Wanting to improve your FreeRTOS skills and productivity *
|
12 |
|
|
* *
|
13 |
|
|
* then take a look at the FreeRTOS books - available as PDF or paperback *
|
14 |
|
|
* *
|
15 |
|
|
* "Using the FreeRTOS Real Time Kernel - a Practical Guide" *
|
16 |
|
|
* http://www.FreeRTOS.org/Documentation *
|
17 |
|
|
* *
|
18 |
|
|
* A pdf reference manual is also available. Both are usually delivered *
|
19 |
|
|
* to your inbox within 20 minutes to two hours when purchased between 8am *
|
20 |
|
|
* and 8pm GMT (although please allow up to 24 hours in case of *
|
21 |
|
|
* exceptional circumstances). Thank you for your support! *
|
22 |
|
|
* *
|
23 |
|
|
***************************************************************************
|
24 |
|
|
|
25 |
|
|
This file is part of the FreeRTOS distribution.
|
26 |
|
|
|
27 |
|
|
FreeRTOS is free software; you can redistribute it and/or modify it under
|
28 |
|
|
the terms of the GNU General Public License (version 2) as published by the
|
29 |
|
|
Free Software Foundation AND MODIFIED BY the FreeRTOS exception.
|
30 |
|
|
***NOTE*** The exception to the GPL is included to allow you to distribute
|
31 |
|
|
a combined work that includes FreeRTOS without being obliged to provide the
|
32 |
|
|
source code for proprietary components outside of the FreeRTOS kernel.
|
33 |
|
|
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT
|
34 |
|
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
35 |
|
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
36 |
|
|
more details. You should have received a copy of the GNU General Public
|
37 |
|
|
License and the FreeRTOS license exception along with FreeRTOS; if not it
|
38 |
|
|
can be viewed here: http://www.freertos.org/a00114.html and also obtained
|
39 |
|
|
by writing to Richard Barry, contact details for whom are available on the
|
40 |
|
|
FreeRTOS WEB site.
|
41 |
|
|
|
42 |
|
|
1 tab == 4 spaces!
|
43 |
|
|
|
44 |
|
|
http://www.FreeRTOS.org - Documentation, latest information, license and
|
45 |
|
|
contact details.
|
46 |
|
|
|
47 |
|
|
http://www.SafeRTOS.com - A version that is certified for use in safety
|
48 |
|
|
critical systems.
|
49 |
|
|
|
50 |
|
|
http://www.OpenRTOS.com - Commercial support, development, porting,
|
51 |
|
|
licensing and training services.
|
52 |
|
|
*/
|
53 |
|
|
|
54 |
|
|
/*-----------------------------------------------------------
|
55 |
|
|
* Implementation of functions defined in portable.h for the NIOS2 port.
|
56 |
|
|
*----------------------------------------------------------*/
|
57 |
|
|
|
58 |
|
|
/* Standard Includes. */
|
59 |
|
|
#include <string.h>
|
60 |
|
|
#include <errno.h>
|
61 |
|
|
|
62 |
|
|
/* Altera includes. */
|
63 |
|
|
#include "sys/alt_irq.h"
|
64 |
|
|
#include "altera_avalon_timer_regs.h"
|
65 |
|
|
#include "priv/alt_irq_table.h"
|
66 |
|
|
|
67 |
|
|
/* Scheduler includes. */
|
68 |
|
|
#include "FreeRTOS.h"
|
69 |
|
|
#include "task.h"
|
70 |
|
|
|
71 |
|
|
/* Interrupts are enabled. */
|
72 |
|
|
#define portINITIAL_ESTATUS ( portSTACK_TYPE ) 0x01
|
73 |
|
|
|
74 |
|
|
/*-----------------------------------------------------------*/
|
75 |
|
|
|
76 |
|
|
/*
|
77 |
|
|
* Setup the timer to generate the tick interrupts.
|
78 |
|
|
*/
|
79 |
|
|
static void prvSetupTimerInterrupt( void );
|
80 |
|
|
|
81 |
|
|
/*
|
82 |
|
|
* Call back for the alarm function.
|
83 |
|
|
*/
|
84 |
|
|
void vPortSysTickHandler( void * context, alt_u32 id );
|
85 |
|
|
|
86 |
|
|
/*-----------------------------------------------------------*/
|
87 |
|
|
|
88 |
|
|
void prvReadGp( unsigned long *ulValue )
|
89 |
|
|
{
|
90 |
|
|
asm( "stw gp, (r4) " );
|
91 |
|
|
};
|
92 |
|
|
/*-----------------------------------------------------------*/
|
93 |
|
|
|
94 |
|
|
/*
|
95 |
|
|
* See header file for description.
|
96 |
|
|
*/
|
97 |
|
|
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
|
98 |
|
|
{
|
99 |
|
|
portSTACK_TYPE *pxFramePointer = pxTopOfStack - 1;
|
100 |
|
|
portSTACK_TYPE xGlobalPointer;
|
101 |
|
|
|
102 |
|
|
prvReadGp( &xGlobalPointer );
|
103 |
|
|
|
104 |
|
|
/* End of stack marker. */
|
105 |
|
|
*pxTopOfStack = 0xdeadbeef;
|
106 |
|
|
pxTopOfStack--;
|
107 |
|
|
|
108 |
|
|
*pxTopOfStack = ( portSTACK_TYPE ) pxFramePointer;
|
109 |
|
|
pxTopOfStack--;
|
110 |
|
|
|
111 |
|
|
*pxTopOfStack = xGlobalPointer;
|
112 |
|
|
|
113 |
|
|
/* Space for R23 to R16. */
|
114 |
|
|
pxTopOfStack -= 9;
|
115 |
|
|
|
116 |
|
|
*pxTopOfStack = ( portSTACK_TYPE ) pxCode;
|
117 |
|
|
pxTopOfStack--;
|
118 |
|
|
|
119 |
|
|
*pxTopOfStack = portINITIAL_ESTATUS;
|
120 |
|
|
|
121 |
|
|
/* Space for R15 to R5. */
|
122 |
|
|
pxTopOfStack -= 12;
|
123 |
|
|
|
124 |
|
|
*pxTopOfStack = ( portSTACK_TYPE ) pvParameters;
|
125 |
|
|
|
126 |
|
|
/* Space for R3 to R1, muldiv and RA. */
|
127 |
|
|
pxTopOfStack -= 5;
|
128 |
|
|
|
129 |
|
|
return pxTopOfStack;
|
130 |
|
|
}
|
131 |
|
|
/*-----------------------------------------------------------*/
|
132 |
|
|
|
133 |
|
|
/*
|
134 |
|
|
* See header file for description.
|
135 |
|
|
*/
|
136 |
|
|
portBASE_TYPE xPortStartScheduler( void )
|
137 |
|
|
{
|
138 |
|
|
/* Start the timer that generates the tick ISR. Interrupts are disabled
|
139 |
|
|
here already. */
|
140 |
|
|
prvSetupTimerInterrupt();
|
141 |
|
|
|
142 |
|
|
/* Start the first task. */
|
143 |
|
|
asm volatile ( " movia r2, restore_sp_from_pxCurrentTCB \n"
|
144 |
|
|
" jmp r2 " );
|
145 |
|
|
|
146 |
|
|
/* Should not get here! */
|
147 |
|
|
return 0;
|
148 |
|
|
}
|
149 |
|
|
/*-----------------------------------------------------------*/
|
150 |
|
|
|
151 |
|
|
void vPortEndScheduler( void )
|
152 |
|
|
{
|
153 |
|
|
/* It is unlikely that the NIOS2 port will require this function as there
|
154 |
|
|
is nothing to return to. */
|
155 |
|
|
}
|
156 |
|
|
/*-----------------------------------------------------------*/
|
157 |
|
|
|
158 |
|
|
/*
|
159 |
|
|
* Setup the systick timer to generate the tick interrupts at the required
|
160 |
|
|
* frequency.
|
161 |
|
|
*/
|
162 |
|
|
void prvSetupTimerInterrupt( void )
|
163 |
|
|
{
|
164 |
|
|
/* Try to register the interrupt handler. */
|
165 |
|
|
if ( -EINVAL == alt_irq_register( SYS_CLK_IRQ, 0x0, vPortSysTickHandler ) )
|
166 |
|
|
{
|
167 |
|
|
/* Failed to install the Interrupt Handler. */
|
168 |
|
|
asm( "break" );
|
169 |
|
|
}
|
170 |
|
|
else
|
171 |
|
|
{
|
172 |
|
|
/* Configure SysTick to interrupt at the requested rate. */
|
173 |
|
|
IOWR_ALTERA_AVALON_TIMER_CONTROL( SYS_CLK_BASE, ALTERA_AVALON_TIMER_CONTROL_STOP_MSK );
|
174 |
|
|
IOWR_ALTERA_AVALON_TIMER_PERIODL( SYS_CLK_BASE, ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) & 0xFFFF );
|
175 |
|
|
IOWR_ALTERA_AVALON_TIMER_PERIODH( SYS_CLK_BASE, ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) >> 16 );
|
176 |
|
|
IOWR_ALTERA_AVALON_TIMER_CONTROL( SYS_CLK_BASE, ALTERA_AVALON_TIMER_CONTROL_CONT_MSK | ALTERA_AVALON_TIMER_CONTROL_START_MSK | ALTERA_AVALON_TIMER_CONTROL_ITO_MSK );
|
177 |
|
|
}
|
178 |
|
|
|
179 |
|
|
/* Clear any already pending interrupts generated by the Timer. */
|
180 |
|
|
IOWR_ALTERA_AVALON_TIMER_STATUS( SYS_CLK_BASE, ~ALTERA_AVALON_TIMER_STATUS_TO_MSK );
|
181 |
|
|
}
|
182 |
|
|
/*-----------------------------------------------------------*/
|
183 |
|
|
|
184 |
|
|
void vPortSysTickHandler( void * context, alt_u32 id )
|
185 |
|
|
{
|
186 |
|
|
/* Increment the Kernel Tick. */
|
187 |
|
|
vTaskIncrementTick();
|
188 |
|
|
|
189 |
|
|
/* If using preemption, also force a context switch. */
|
190 |
|
|
#if configUSE_PREEMPTION == 1
|
191 |
|
|
vTaskSwitchContext();
|
192 |
|
|
#endif
|
193 |
|
|
|
194 |
|
|
/* Clear the interrupt. */
|
195 |
|
|
IOWR_ALTERA_AVALON_TIMER_STATUS( SYS_CLK_BASE, ~ALTERA_AVALON_TIMER_STATUS_TO_MSK );
|
196 |
|
|
}
|
197 |
|
|
/*-----------------------------------------------------------*/
|
198 |
|
|
|
199 |
|
|
/** This function is a re-implementation of the Altera provided function.
|
200 |
|
|
* The function is re-implemented to prevent it from enabling an interrupt
|
201 |
|
|
* when it is registered. Interrupts should only be enabled after the FreeRTOS.org
|
202 |
|
|
* kernel has its scheduler started so that contexts are saved and switched
|
203 |
|
|
* correctly.
|
204 |
|
|
*/
|
205 |
|
|
int alt_irq_register( alt_u32 id, void* context, void (*handler)(void*, alt_u32) )
|
206 |
|
|
{
|
207 |
|
|
int rc = -EINVAL;
|
208 |
|
|
alt_irq_context status;
|
209 |
|
|
|
210 |
|
|
if (id < ALT_NIRQ)
|
211 |
|
|
{
|
212 |
|
|
/*
|
213 |
|
|
* interrupts are disabled while the handler tables are updated to ensure
|
214 |
|
|
* that an interrupt doesn't occur while the tables are in an inconsistent
|
215 |
|
|
* state.
|
216 |
|
|
*/
|
217 |
|
|
|
218 |
|
|
status = alt_irq_disable_all ();
|
219 |
|
|
|
220 |
|
|
alt_irq[id].handler = handler;
|
221 |
|
|
alt_irq[id].context = context;
|
222 |
|
|
|
223 |
|
|
rc = (handler) ? alt_irq_enable (id): alt_irq_disable (id);
|
224 |
|
|
|
225 |
|
|
/* alt_irq_enable_all(status); This line is removed to prevent the interrupt from being immediately enabled. */
|
226 |
|
|
}
|
227 |
|
|
|
228 |
|
|
return rc;
|
229 |
|
|
}
|
230 |
|
|
/*-----------------------------------------------------------*/
|
231 |
|
|
|