Files
atomthreads/platforms/qemu_integratorcp/modules.c

161 lines
4.5 KiB
C

/*
* Copyright (c) 2012, Natie van Rooyen. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. No personal names or organizations' names associated with the
* Atomthreads project may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE ATOMTHREADS PROJECT AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "modules.h"
#include <stdio.h>
#include <stdarg.h>
#include "atomport.h"
#include "atomport-private.h"
#include "atom.h"
#include "atomport.h"
#include "types.h"
/** Imports required by C startup code */
extern unsigned long _end_text, _start_data, _end_data, _start_bss, _end_bss;
extern int main(void);
/** Board-specific registers */
ICP_TIMER_T * const board_timer_0 = (ICP_TIMER_T*)BOARD_BASE_ADDRESS_TIMER_0;
ICP_PIC_T * const board_pic = (ICP_PIC_T*)BOARD_BASE_ADDRESS_PIC;
/** TIMER0 clock speed (Hz) */
#define TIMER0_CLOCK_SPEED 40000000
/**
* \b dbg_format_msg
*
* Same as printf.
*
*/
void
dbg_format_msg (char *format, ...)
{
va_list args;
static char msg[256] ;
CRITICAL_STORE ;
va_start (args, format) ;
CRITICAL_START() ;
vsnprintf ((char*)msg, 256, (char*)format, args) ;
printf (msg) ;
CRITICAL_END() ;
}
/**
* \b _mainCRTStartup
*
* C startup code for environments without a suitable built-in one.
* May be provided by the compiler toolchain in some cases.
*
*/
extern void _mainCRTStartup (void) __attribute__((weak));
void _mainCRTStartup(void)
{
unsigned long *src;
#ifdef ROM
unsigned long *dst;
#endif
#ifdef ROM
// Running from ROM: copy data section to RAM
src = &_end_text;
dst = &_start_data;
while(dst < &_end_data)
*(dst++) = *(src++);
#endif
// Clear BSS
src = &_start_bss;
while(src < &_end_bss)
*(src++) = 0;
// Jump to main application entry point
main();
}
/**
* \b low_level_init
*
* Initializes the PIC and start the system timer tick intrerupt.
*
*/
int
low_level_init (void)
{
board_pic->IRQ_ENABLECLR = ICP_PIC_IRQ_TIMERINT0 ;
board_timer_0->INTCLR = 1 ;
board_pic->IRQ_ENABLESET |= ICP_PIC_IRQ_TIMERINT0 ;
/* Set the timer to go off 100 times per second (input clock speed is 40MHz) */
board_timer_0->LOAD = TIMER0_CLOCK_SPEED / SYSTEM_TICKS_PER_SEC ;
board_timer_0->BGLOAD = TIMER0_CLOCK_SPEED / SYSTEM_TICKS_PER_SEC ;
board_timer_0->CONTROL = ICP_TIMER_CONTROL_ENABLE |
ICP_TIMER_CONTROL_MODE |
ICP_TIMER_CONTROL_IE |
/*ICP_TIMER_CONTROL_PRESCALE_256 |*/
ICP_TIMER_CONTROL_TIMER_SIZE ;
return 0 ;
}
/**
* \b __context_preempt_handler
*
* System timer tic interupt handler.
*
*/
void
__context_preempt_handler (void)
{
unsigned int status = board_pic->IRQ_STATUS ;
if (status | ICP_PIC_IRQ_TIMERINT0) {
atomIntEnter();
/* Call the OS system tick handler */
atomTimerTick();
/* ack the interrupt */
board_timer_0->INTCLR = 0x1 ;
/* Call the interrupt exit routine */
atomIntExit(TRUE);
}
}