/**
* @file
*
* @brief SuperH CPU Support
*
* This file contains information pertaining to the Hitachi SH
* processor.
*/
/*
* Authors: Ralf Corsepius (corsepiu@faw.uni-ulm.de) and
* Bernd Becker (becker@faw.uni-ulm.de)
*
* COPYRIGHT (c) 1997-1998, FAW Ulm, Germany
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
*
* COPYRIGHT (c) 1998-2001.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/system.h>
#include <rtems/score/isr.h>
#include <rtems/score/sh_io.h>
#include <rtems/score/cpu.h>
#include <rtems/score/sh.h>
/* referenced in start.S */
extern proc_ptr vectab[] ;
proc_ptr vectab[256] ;
extern proc_ptr _Hardware_isr_Table[];
#if SH_HAS_FPU
Context_Control_fp _CPU_Null_fp_context;
#endif
/* _CPU_Initialize
*
* This routine performs processor dependent initialization.
*
* INPUT PARAMETERS: NONE
*/
void _CPU_Initialize(void)
{
register uint32_t level = 0;
/*
* If there is not an easy way to initialize the FP context
* during Context_Initialize, then it is usually easier to
* save an "uninitialized" FP context here and copy it to
* the task's during Context_Initialize.
*/
/* FP context initialization support goes here */
#if SH_HAS_FPU
/* FIXME: When not to use SH4_FPSCR_PR ? */
#ifdef __SH4__
_CPU_Null_fp_context.fpscr = SH4_FPSCR_DN | SH4_FPSCR_RM | SH4_FPSCR_PR;
#endif
#ifdef __SH3E__
/* FIXME: Wild guess :) */
_CPU_Null_fp_context.fpscr = SH4_FPSCR_DN | SH4_FPSCR_RM;
#endif
#endif
/* enable interrupts */
_CPU_ISR_Set_level( level ) ;
}
/*
* _CPU_ISR_Get_level
*/
uint32_t _CPU_ISR_Get_level( void )
{
/*
* This routine returns the current interrupt level.
*/
register uint32_t _mask ;
sh_get_interrupt_level( _mask );
return ( _mask);
}
/*
* _CPU_ISR_install_raw_handler
*/
void _CPU_ISR_install_raw_handler(
uint32_t vector,
proc_ptr new_handler,
proc_ptr *old_handler
)
{
/*
* This is where we install the interrupt handler into the "raw" interrupt
* table used by the CPU to dispatch interrupt handlers.
*/
volatile proc_ptr *vbr ;
#if SH_PARANOID_ISR
uint32_t level ;
sh_disable_interrupts( level );
#endif
/* get vbr */
__asm__ ( "stc vbr,%0" : "=r" (vbr) );
*old_handler = vbr[vector] ;
vbr[vector] = new_handler ;
#if SH_PARANOID_ISR
sh_enable_interrupts( level );
#endif
}
/*
* _CPU_ISR_install_vector
*
* This kernel routine installs the RTEMS handler for the
* specified vector.
*
* Input parameters:
* vector - interrupt vector number
* old_handler - former ISR for this vector number
* new_handler - replacement ISR for this vector number
*
* Output parameters: NONE
*
*/
void _CPU_ISR_install_vector(
uint32_t vector,
proc_ptr new_handler,
proc_ptr *old_handler
)
{
#if defined(__sh1__) || defined(__sh2__)
proc_ptr ignored ;
#endif
*old_handler = _ISR_Vector_table[ vector ];
/*
* If the interrupt vector table is a table of pointer to isr entry
* points, then we need to install the appropriate RTEMS interrupt
* handler for this vector number.
*/
#if defined(__sh1__) || defined(__sh2__)
_CPU_ISR_install_raw_handler(vector, _Hardware_isr_Table[vector], &ignored );
#endif
/*
* We put the actual user ISR address in '_ISR_Vector_table'.
* This will be used by __ISR_Handler so the user gets control.
*/
_ISR_Vector_table[ vector ] = new_handler;
}
/*
* _CPU_Thread_Idle_body
*
* NOTES:
*
* 1. This is the same as the regular CPU independent algorithm.
*
* 2. If you implement this using a "halt", "idle", or "shutdown"
* instruction, then don't forget to put it in an infinite loop.
*
* 3. Be warned. Some processors with onboard DMA have been known
* to stop the DMA if the CPU were put in IDLE mode. This might
* also be a problem with other on-chip peripherals. So use this
* hook with caution.
*/
#if (CPU_PROVIDES_IDLE_THREAD_BODY == TRUE)
void *_CPU_Thread_Idle_body( uintptr_t ignored )
{
for( ; ; )
{
__asm__ volatile("nop");
}
/* insert your "halt" instruction here */ ;
}
#endif
void _CPU_Context_Initialize(
Context_Control *_the_context,
void *_stack_base,
uint32_t _size,
uint32_t _isr,
void (*_entry_point)(void),
int _is_fp,
void *_tls_base)
{
_the_context->r15 = (uint32_t *) ((uint32_t) (_stack_base) + (_size) );
#if defined(__sh1__) || defined(__sh2__) || defined(__SH2E__)
_the_context->sr = (_isr << 4) & 0x00f0 ;
#else
_the_context->sr = SH4_SR_MD | ((_isr << 4) & 0x00f0);
#endif
_the_context->pr = (uint32_t *) _entry_point ;
#if 0 && SH_HAS_FPU
/* Disable FPU if it is non-fp task */
if(!_is_fp)
_the_context->sr |= SH4_SR_FD;
#endif
}
