/*
* This file contains the basic algorithms for all assembly code used
* in an specific CPU port of RTEMS. These algorithms must be implemented
* in assembly language
*
* NOTE: This port uses a C file with inline assembler instructions
*
* 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.
* 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.com/license/LICENSE.
*
* $Id$
*/
/*
* This is supposed to be an assembly file. This means that system.h
* and cpu.h should not be included in a "real" cpu_asm file. An
* implementation in assembly should include "cpu_asm.h"
*/
#include <rtems/system.h>
#include <rtems/score/cpu.h>
#include <rtems/score/isr.h>
#include <rtems/score/thread.h>
#include <rtems/score/sh.h>
#include <rtems/score/ispsh7045.h>
#include <rtems/score/iosh7045.h>
#include <rtems/score/sh_io.h>
/* from cpu_isps.c */
extern proc_ptr _Hardware_isr_Table[];
#if( CPU_HAS_SOFTWARE_INTERRUPT_STACK == TRUE)
unsigned long *_old_stack_ptr;
#endif
register unsigned long *stack_ptr asm("r15");
/*
* sh_set_irq_priority
*
* this function sets the interrupt level of the specified interrupt
*
* parameters:
* - irq : interrupt number
* - prio: priority to set for this interrupt number
*
* returns: 0 if ok
* -1 on error
*/
unsigned int sh_set_irq_priority(
unsigned int irq,
unsigned int prio )
{
uint32_t shiftcount;
uint32_t prioreg;
uint16_t temp16;
uint32_t level;
/*
* first check for valid interrupt
*/
if(( irq > 156) || (irq < 64) || (_Hardware_isr_Table[irq] == _dummy_isp))
return -1;
/*
* check for valid irq priority
*/
if( prio > 15 )
return -1;
/*
* look up appropriate interrupt priority register
*/
if( irq > 71)
{
irq = irq - 72;
shiftcount = 12 - ((irq & ~0x03) % 16);
switch( irq / 16)
{
case 0: { prioreg = INTC_IPRC; break;}
case 1: { prioreg = INTC_IPRD; break;}
case 2: { prioreg = INTC_IPRE; break;}
case 3: { prioreg = INTC_IPRF; break;}
case 4: { prioreg = INTC_IPRG; break;}
case 5: { prioreg = INTC_IPRH; break;}
default: return -1;
}
}
else
{
shiftcount = 12 - 4 * ( irq % 4);
if( irq > 67)
prioreg = INTC_IPRB;
else
prioreg = INTC_IPRA;
}
/*
* Set the interrupt priority register
*/
_CPU_ISR_Disable( level );
temp16 = read16( prioreg);
temp16 &= ~( 15 << shiftcount);
temp16 |= prio << shiftcount;
write16( temp16, prioreg);
_CPU_ISR_Enable( level );
return 0;
}
/*
* _CPU_Context_save_fp_context
*
* This routine is responsible for saving the FP context
* at *fp_context_ptr. If the point to load the FP context
* from is changed then the pointer is modified by this routine.
*
* Sometimes a macro implementation of this is in cpu.h which dereferences
* the ** and a similarly named routine in this file is passed something
* like a (Context_Control_fp *). The general rule on making this decision
* is to avoid writing assembly language.
*/
void _CPU_Context_save_fp(
void **fp_context_ptr
)
{
}
/*
* _CPU_Context_restore_fp_context
*
* This routine is responsible for restoring the FP context
* at *fp_context_ptr. If the point to load the FP context
* from is changed then the pointer is modified by this routine.
*
* Sometimes a macro implementation of this is in cpu.h which dereferences
* the ** and a similarly named routine in this file is passed something
* like a (Context_Control_fp *). The general rule on making this decision
* is to avoid writing assembly language.
*/
void _CPU_Context_restore_fp(
void **fp_context_ptr
)
{
}
/* _CPU_Context_switch
*
* This routine performs a normal non-FP context switch.
*/
/* within __CPU_Context_switch:
* _CPU_Context_switch
* _CPU_Context_restore
*
* This routine is generally used only to restart self in an
* efficient manner. It may simply be a label in _CPU_Context_switch.
*
* NOTE: It should be safe not to store r4, r5
*
* NOTE: It is doubtful if r0 is really needed to be stored
*
* NOTE: gbr is added, but should not be necessary, as it is
* only used globally in this port.
*/
/*
* FIXME: This is an ugly hack, but we wanted to avoid recalculating
* the offset each time Context_Control is changed
*/
void __CPU_Context_switch(
Context_Control *run, /* r4 */
Context_Control *heir /* r5 */
)
{
asm volatile("\n\
.global __CPU_Context_switch\n\
__CPU_Context_switch:\n\
\n\
add %0,r4\n\
\n\
stc.l sr,@-r4\n\
stc.l gbr,@-r4\n\
mov.l r0,@-r4\n\
mov.l r1,@-r4\n\
mov.l r2,@-r4\n\
mov.l r3,@-r4\n\
\n\
mov.l r6,@-r4\n\
mov.l r7,@-r4\n\
mov.l r8,@-r4\n\
mov.l r9,@-r4\n\
mov.l r10,@-r4\n\
mov.l r11,@-r4\n\
mov.l r12,@-r4\n\
mov.l r13,@-r4\n\
mov.l r14,@-r4\n\
sts.l pr,@-r4\n\
sts.l mach,@-r4\n\
sts.l macl,@-r4\n\
mov.l r15,@-r4\n\
\n\
mov r5, r4"
:: "i" (sizeof(Context_Control))
);
asm volatile("\n\
.global __CPU_Context_restore\n\
__CPU_Context_restore:\n\
mov.l @r4+,r15\n\
lds.l @r4+,macl\n\
lds.l @r4+,mach\n\
lds.l @r4+,pr\n\
mov.l @r4+,r14\n\
mov.l @r4+,r13\n\
mov.l @r4+,r12\n\
mov.l @r4+,r11\n\
mov.l @r4+,r10\n\
mov.l @r4+,r9\n\
mov.l @r4+,r8\n\
mov.l @r4+,r7\n\
mov.l @r4+,r6\n\
\n\
mov.l @r4+,r3\n\
mov.l @r4+,r2\n\
mov.l @r4+,r1\n\
mov.l @r4+,r0\n\
ldc.l @r4+,gbr\n\
ldc.l @r4+,sr\n\
\n\
rts\n\
nop" );
}
/*
* This routine provides the RTEMS interrupt management.
*/
void __ISR_Handler( uint32_t vector)
{
register uint32_t level;
_CPU_ISR_Disable( level );
_Thread_Dispatch_disable_level++;
#if( CPU_HAS_SOFTWARE_INTERRUPT_STACK == TRUE)
if( _ISR_Nest_level == 0 )
{
/* Install irq stack */
_old_stack_ptr = stack_ptr;
stack_ptr = _CPU_Interrupt_stack_high;
}
#endif
_ISR_Nest_level++;
_CPU_ISR_Enable( level );
/* call isp */
if( _ISR_Vector_table[ vector])
(*_ISR_Vector_table[ vector ])( vector );
_CPU_ISR_Disable( level );
_Thread_Dispatch_disable_level--;
_ISR_Nest_level--;
#if( CPU_HAS_SOFTWARE_INTERRUPT_STACK == TRUE)
if( _ISR_Nest_level == 0 )
/* restore old stack pointer */
stack_ptr = _old_stack_ptr;
#endif
_CPU_ISR_Enable( level );
if ( _ISR_Nest_level )
return;
if ( _Thread_Dispatch_disable_level ) {
_ISR_Signals_to_thread_executing = FALSE;
return;
}
if ( _Context_Switch_necessary || _ISR_Signals_to_thread_executing ) {
_ISR_Signals_to_thread_executing = FALSE;
_Thread_Dispatch();
}
}
