binutils-gdb/sim/m68hc11/interrupts.c

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2000-07-27 13:23:39 +02:00
/* interrupts.c -- 68HC11 Interrupts Emulation
Copyright 1999, 2000 Free Software Foundation, Inc.
Written by Stephane Carrez (stcarrez@worldnet.fr)
This file is part of GDB, GAS, and the GNU binutils.
GDB, GAS, and the GNU binutils are free software; you can redistribute
them and/or modify them under the terms of the GNU General Public
License as published by the Free Software Foundation; either version
1, or (at your option) any later version.
GDB, GAS, and the GNU binutils are distributed in the hope that they
will be useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this file; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "sim-main.h"
struct interrupt_def idefs[] = {
/* Serial interrupts. */
{ M6811_INT_SCI, M6811_SCSR, M6811_TDRE, M6811_SCCR2, M6811_TIE },
{ M6811_INT_SCI, M6811_SCSR, M6811_TC, M6811_SCCR2, M6811_TCIE },
{ M6811_INT_SCI, M6811_SCSR, M6811_RDRF, M6811_SCCR2, M6811_RIE },
{ M6811_INT_SCI, M6811_SCSR, M6811_IDLE, M6811_SCCR2, M6811_ILIE },
/* SPI interrupts. */
{ M6811_INT_SPI, M6811_SPSR, M6811_SPIF, M6811_SPCR, M6811_SPIE },
/* Realtime interrupts. */
{ M6811_INT_TCTN, M6811_TFLG2, M6811_TOF, M6811_TMSK2, M6811_TOI },
{ M6811_INT_RT, M6811_TFLG2, M6811_RTIF, M6811_TMSK2, M6811_RTII },
/* Output compare interrupts. */
{ M6811_INT_OUTCMP1, M6811_TFLG1, M6811_OC1F, M6811_TMSK1, M6811_OC1I },
{ M6811_INT_OUTCMP2, M6811_TFLG1, M6811_OC2F, M6811_TMSK1, M6811_OC2I },
{ M6811_INT_OUTCMP3, M6811_TFLG1, M6811_OC3F, M6811_TMSK1, M6811_OC3I },
{ M6811_INT_OUTCMP4, M6811_TFLG1, M6811_OC4F, M6811_TMSK1, M6811_OC4I },
{ M6811_INT_OUTCMP5, M6811_TFLG1, M6811_OC5F, M6811_TMSK1, M6811_OC5I },
/* Input compare interrupts. */
{ M6811_INT_INCMP1, M6811_TFLG1, M6811_IC1F, M6811_TMSK1, M6811_IC1I },
{ M6811_INT_INCMP2, M6811_TFLG1, M6811_IC2F, M6811_TMSK1, M6811_IC2I },
{ M6811_INT_INCMP3, M6811_TFLG1, M6811_IC3F, M6811_TMSK1, M6811_IC3I },
#if 0
{ M6811_INT_COPRESET, M6811_CONFIG, M6811_NOCOP, 0, 0 },
{ M6811_INT_COPFAIL, M6811_CONFIG, M6811_NOCOP, 0, 0 }
#endif
};
#define TableSize(X) (sizeof X / sizeof(X[0]))
#define CYCLES_MAX ((((signed64) 1) << 62) - 1)
/* Initialize the interrupts of the processor. */
int
interrupts_initialize (struct _sim_cpu *proc)
{
struct interrupts *interrupts = &proc->cpu_interrupts;
int i;
interrupts->cpu = proc;
interrupts->pending_mask = 0;
interrupts->vectors_addr = 0xffc0;
interrupts->nb_interrupts_raised = 0;
interrupts->min_mask_cycles = CYCLES_MAX;
interrupts->max_mask_cycles = 0;
interrupts->start_mask_cycle = -1;
interrupts->xirq_start_mask_cycle = -1;
interrupts->xirq_max_mask_cycles = 0;
interrupts->xirq_min_mask_cycles = CYCLES_MAX;
for (i = 0; i < M6811_INT_NUMBER; i++)
{
interrupts->interrupt_order[i] = i;
}
return 0;
}
/* Update the mask of pending interrupts. This operation must be called
when the state of some 68HC11 IO registers changes. It looks the
different registers that indicate a pending interrupt (timer, SCI, SPI,
...) and records the interrupt if it's there and enabled. */
void
interrupts_update_pending (struct interrupts *interrupts)
{
int i;
uint8 *ioregs;
ioregs = &interrupts->cpu->ios[0];
for (i = 0; i < TableSize(idefs); i++)
{
struct interrupt_def *idef = &idefs[i];
uint8 data;
/* Look if the interrupt is enabled. */
if (idef->enable_paddr)
{
data = ioregs[idef->enable_paddr];
if (!(data & idef->enabled_mask))
continue;
}
/* Interrupt is enabled, see if it's there. */
data = ioregs[idef->int_paddr];
if (!(data & idef->int_mask))
continue;
/* Ok, raise it. */
interrupts->pending_mask |= (1 << idef->int_number);
}
}
/* Finds the current active and non-masked interrupt.
Returns the interrupt number (index in the vector table) or -1
if no interrupt can be serviced. */
int
interrupts_get_current (struct interrupts *interrupts)
{
int i;
if (interrupts->pending_mask == 0)
return -1;
/* SWI and illegal instructions are simulated by an interrupt.
They are not maskable. */
if (interrupts->pending_mask & (1 << M6811_INT_SWI))
{
interrupts->pending_mask &= ~(1 << M6811_INT_SWI);
return M6811_INT_SWI;
}
if (interrupts->pending_mask & (1 << M6811_INT_ILLEGAL))
{
interrupts->pending_mask &= ~(1 << M6811_INT_ILLEGAL);
return M6811_INT_ILLEGAL;
}
/* If there is a non maskable interrupt, go for it (unless we are masked
by the X-bit. */
if (interrupts->pending_mask & (1 << M6811_INT_XIRQ))
{
if (cpu_get_ccr_X (interrupts->cpu) == 0)
{
interrupts->pending_mask &= ~(1 << M6811_INT_XIRQ);
return M6811_INT_XIRQ;
}
return -1;
}
/* Interrupts are masked, do nothing. */
if (cpu_get_ccr_I (interrupts->cpu) == 1)
{
return -1;
}
/* Returns the first interrupt number which is pending.
The interrupt priority is specified by the table `interrupt_order'. */
for (i = 0; i < M6811_INT_NUMBER; i++)
{
enum M6811_INT int_number = interrupts->interrupt_order[i];
if (interrupts->pending_mask & (1 << int_number))
{
interrupts->pending_mask &= ~(1 << int_number);
return int_number;
}
}
return -1;
}
/* Process the current interrupt if there is one. This operation must
be called after each instruction to handle the interrupts. If interrupts
are masked, it does nothing. */
int
interrupts_process (struct interrupts *interrupts)
{
int id;
uint8 ccr;
/* See if interrupts are enabled/disabled and keep track of the
number of cycles the interrupts are masked. Such information is
then reported by the info command. */
ccr = cpu_get_ccr (interrupts->cpu);
if (ccr & M6811_I_BIT)
{
if (interrupts->start_mask_cycle < 0)
interrupts->start_mask_cycle = cpu_current_cycle (interrupts->cpu);
}
else if (interrupts->start_mask_cycle >= 0
&& (ccr & M6811_I_BIT) == 0)
{
signed64 t = cpu_current_cycle (interrupts->cpu);
t -= interrupts->start_mask_cycle;
if (t < interrupts->min_mask_cycles)
interrupts->min_mask_cycles = t;
if (t > interrupts->max_mask_cycles)
interrupts->max_mask_cycles = t;
interrupts->start_mask_cycle = -1;
}
if (ccr & M6811_X_BIT)
{
if (interrupts->xirq_start_mask_cycle < 0)
interrupts->xirq_start_mask_cycle
= cpu_current_cycle (interrupts->cpu);
}
else if (interrupts->xirq_start_mask_cycle >= 0
&& (ccr & M6811_X_BIT) == 0)
{
signed64 t = cpu_current_cycle (interrupts->cpu);
t -= interrupts->xirq_start_mask_cycle;
if (t < interrupts->xirq_min_mask_cycles)
interrupts->xirq_min_mask_cycles = t;
if (t > interrupts->xirq_max_mask_cycles)
interrupts->xirq_max_mask_cycles = t;
interrupts->xirq_start_mask_cycle = -1;
}
id = interrupts_get_current (interrupts);
if (id >= 0)
{
uint16 addr;
cpu_push_all (interrupts->cpu);
addr = memory_read16 (interrupts->cpu,
interrupts->vectors_addr + id * 2);
cpu_call (interrupts->cpu, addr);
/* Now, protect from nested interrupts. */
if (id == M6811_INT_XIRQ)
{
cpu_set_ccr_X (interrupts->cpu, 1);
}
else
{
cpu_set_ccr_I (interrupts->cpu, 1);
}
interrupts->nb_interrupts_raised++;
cpu_add_cycles (interrupts->cpu, 14);
return 1;
}
return 0;
}
void
interrupts_raise (struct interrupts *interrupts, enum M6811_INT number)
{
interrupts->pending_mask |= (1 << number);
interrupts->nb_interrupts_raised ++;
}
void
interrupts_info (SIM_DESC sd, struct interrupts *interrupts)
{
if (interrupts->start_mask_cycle >= 0)
{
signed64 t = cpu_current_cycle (interrupts->cpu);
t -= interrupts->start_mask_cycle;
if (t > interrupts->max_mask_cycles)
interrupts->max_mask_cycles = t;
}
if (interrupts->xirq_start_mask_cycle >= 0)
{
signed64 t = cpu_current_cycle (interrupts->cpu);
t -= interrupts->xirq_start_mask_cycle;
if (t > interrupts->xirq_max_mask_cycles)
interrupts->xirq_max_mask_cycles = t;
}
sim_io_printf (sd, "Interrupts Info:\n");
sim_io_printf (sd, " Interrupts raised: %lu\n",
interrupts->nb_interrupts_raised);
sim_io_printf (sd, " Min interrupts masked sequence: %llu cycles\n",
interrupts->min_mask_cycles == CYCLES_MAX ?
interrupts->max_mask_cycles :
interrupts->min_mask_cycles);
sim_io_printf (sd, " Max interrupts masked sequence: %llu cycles\n",
interrupts->max_mask_cycles);
sim_io_printf (sd, " XIRQ Min interrupts masked sequence: %llu cycles\n",
interrupts->xirq_min_mask_cycles == CYCLES_MAX ?
interrupts->xirq_max_mask_cycles :
interrupts->xirq_min_mask_cycles);
sim_io_printf (sd, " XIRQ Max interrupts masked sequence: %llu cycles\n",
interrupts->xirq_max_mask_cycles);
}