gint/src/mpu/gint_sh7705.c

126 lines
2.4 KiB
C

//---
//
// gint core module: sh7705 interrupt handler
//
// Of course all the work related to interrupts is heavily platform-
// dependent. This module handles interrupts and configures the MPU to
// save and restore the system's configuration when execution ends.
//
//---
#include <gint.h>
#include <timer.h>
#include <7705.h>
//---
// Interrupt codes.
//---
#define IC_RTC_PRI 0x4a0
#define IC_PINT07 0x700
#define IC_TMU0_TUNI0 0x400
#define IC_TMU1_TUNI1 0x420
#define IC_TMU2_TUNI2 0x440
//---
// Interrupt handler.
//---
void gint_7705(void)
{
volatile unsigned int *intevt2 = (unsigned int *)0xa4000000;
unsigned int code = *intevt2;
switch(code)
{
case IC_RTC_PRI:
RTC.RCR2.BIT.PEF = 0;
break;
case IC_TMU0_TUNI0:
timer_interrupt(TIMER_TMU0);
break;
case IC_TMU1_TUNI1:
timer_interrupt(TIMER_TMU1);
break;
case IC_TMU2_TUNI2:
timer_interrupt(TIMER_TMU2);
break;
}
}
//---
// Setup.
//---
static unsigned short iprs[8];
static unsigned char rcr2;
static void gint_priority_lock_7705(void)
{
// Saving the interrupt masks from registers IPRA to IPRH.
iprs[0] = INTC.IPRA.WORD;
iprs[1] = INTC.IPRB.WORD;
iprs[2] = INTX.IPRC.WORD;
iprs[3] = INTX.IPRD.WORD;
iprs[4] = INTX.IPRE.WORD;
iprs[5] = INTX.IPRF.WORD;
iprs[6] = INTX.IPRG.WORD;
iprs[7] = INTX.IPRH.WORD;
// Disabling everything by default to avoid receiving an interrupt that
// the handler doesn't handle, which would cause the user program to
// freeze.
INTC.IPRA.WORD = 0x0000;
INTC.IPRB.WORD = 0x0000;
INTX.IPRC.WORD = 0x0000;
INTX.IPRD.WORD = 0x0000;
INTX.IPRE.WORD = 0x0000;
INTX.IPRF.WORD = 0x0000;
INTX.IPRG.WORD = 0x0000;
INTX.IPRH.WORD = 0x0000;
// Allowing RTC, which handles keyboard.
INTC.IPRA.BIT._RTC = GINT_INTP_RTC;
INTC.IPRA.BIT._TMU0 = GINT_INTP_KEY;
INTC.IPRA.BIT._TMU1 = GINT_INTP_GRAY;
INTC.IPRA.BIT._TMU2 = GINT_INTP_TIMER;
}
static void gint_priority_unlock_7705(void)
{
// Restoring the saved states.
INTC.IPRA.WORD = iprs[0];
INTC.IPRB.WORD = iprs[1];
INTX.IPRC.WORD = iprs[2];
INTX.IPRD.WORD = iprs[3];
INTX.IPRE.WORD = iprs[4];
INTX.IPRF.WORD = iprs[5];
INTX.IPRG.WORD = iprs[6];
INTX.IPRH.WORD = iprs[7];
}
void gint_setup_7705(void)
{
gint_priority_lock_7705();
// Saving the RTC configuration.
rcr2 = RTC.RCR2.BYTE;
// Disabling RTC interrupts by default.
RTC.RCR2.BYTE = 0x09;
}
void gint_stop_7705(void)
{
gint_priority_unlock_7705();
// Restoring the RTC configuration.
RTC.RCR2.BYTE = rcr2;
}