old-cross-binutils/sim/ppc/devices.c

442 lines
10 KiB
C

/* This file is part of the program psim.
Copyright (C) 1994-1995, Andrew Cagney <cagney@highland.com.au>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
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. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _DEVICES_C_
#define _DEVICES_C_
#ifndef STATIC_INLINE_DEVICES
#define STATIC_INLINE_DEVICES STATIC_INLINE
#endif
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <fcntl.h>
#include "basics.h"
#include "device_tree.h"
#include "devices.h"
#include "events.h"
#include "cpu.h" /* drats */
/* Helper functions */
STATIC_INLINE_DEVICES void
parse_device_address(char *name,
unsigned *base,
unsigned *flags)
{
/* extract the two arguments */
name = strchr(name, '@');
if (name == NULL)
error("missing address for device %s\n", name);
name++;
*base = strtol(name, &name, 0);
*flags = (*name == ','
? strtol(name+1, &name, 0)
: 0);
}
/* Simple console device:
Implements a simple text output device that is attached to stdout
of the process running the simulation. The devices has four
word registers:
0: read
4: read-status
8: write
c: write-status
Where a nonzero status register indicates that the device is ready
(input fifo contains a character or output fifo has space).
Illustrates: Mapping read/write to device operations onto actual
registers.
*/
typedef struct _console_buffer {
char buffer;
int status;
event_entry_tag event_tag;
} console_buffer;
typedef struct _console_device {
unsigned_word my_base_address;
int interrupt_delay;
console_buffer input;
console_buffer output;
} console_device;
typedef enum {
console_read_buffer = 0,
console_read_status = 4,
console_write_buffer = 8,
console_write_status = 12,
console_offset_mask = 0xc,
console_size = 16,
} console_offsets;
STATIC_INLINE_DEVICES unsigned64
console_read_callback(device_node *device,
unsigned_word base,
unsigned nr_bytes,
cpu *processor,
unsigned_word cia)
{
console_device *con = (console_device*)device->data;
TRACE(trace_console_device,
("device=0x%x, base=0x%x, nr_bytes=%d\n",
device, base, nr_bytes));
/* handle the request */
switch (base & console_offset_mask) {
case console_read_buffer:
return con->input.buffer;
case console_read_status:
{ /* check for input */
int flags;
int status;
/* get the old status */
flags = fcntl(0, F_GETFL, 0);
if (flags == -1) {
perror("console");
return 0;
}
/* temp, disable blocking IO */
status = fcntl(0, F_SETFL, flags | O_NDELAY);
if (status == -1) {
perror("console");
return 0;
}
/* try for input */
status = read(0, &con->input.buffer, 1);
if (status == 1) {
con->input.status = 1;
}
else {
con->input.status = 0;
}
/* return to regular vewing */
fcntl(0, F_SETFL, flags);
}
return con->input.status;
case console_write_buffer:
return con->output.buffer;
case console_write_status:
return con->output.status;
default:
error("console_read_callback() internal error\n");
return 0;
}
}
STATIC_INLINE_DEVICES void
console_write_callback(device_node *device,
unsigned_word base,
unsigned nr_bytes,
unsigned64 val,
cpu *processor,
unsigned_word cia)
{
console_device *con = (console_device*)device->data;
TRACE(trace_console_device,
("device=0x%x, base=0x%x, nr_bytes=%d, val=0x%x\n",
device, base, nr_bytes, val));
/* check for bus error */
if (base & 0x3) {
error("%s - misaligned base address, base=0x%x, nr_bytes=%d\n",
"console_write_callback", base, nr_bytes);
}
switch (base & console_offset_mask) {
case console_read_buffer: con->input.buffer = val; break;
case console_read_status: con->input.status = val; break;
case console_write_buffer:
TRACE(trace_console_device,
("<%c:%d>", val, val));
printf_filtered("%c", val);
con->output.buffer = val;
con->output.status = 1;
break;
case console_write_status:
con->output.status = val;
break;
}
}
static device_callbacks console_callbacks = {
console_read_callback,
console_write_callback,
};
STATIC_INLINE_DEVICES device_node *
console_create(device_node *parent,
char *name)
{
device_node *device;
unsigned address_base;
unsigned address_flags;
/* create the descriptor */
console_device *console = ZALLOC(console_device);
/* extract the two arguments */
parse_device_address(name, &address_base, &address_flags);
/* fill in the details */
console->my_base_address = address_base;
console->interrupt_delay = address_flags;
console->output.status = 1;
console->output.buffer = '\0';
console->input.status = 0;
console->input.buffer = '\0';
/* insert into the device tree along with its address info */
device = device_node_create(parent, name, sequential_device,
&console_callbacks, console);
device_node_add_address(device,
address_base,
console_size,
device_is_read_write_exec,
NULL);
return device;
}
static device_descriptor console_descriptor = {
"console",
console_create,
};
/* ICU device:
Single 4 byte register. Read returns processor number. Write
interrupts specified processor.
Illustrates passing of events to parent device. Passing of
interrupts to parent bus.
NB: For the sake of illustrating the passing of interrupts. This
device doesn't pass interrupt events to its parent. Instead it
passes them back to its self. */
STATIC_INLINE_DEVICES unsigned64
icu_read_callback(device_node *device,
unsigned_word base,
unsigned nr_bytes,
cpu *processor,
unsigned_word cia)
{
TRACE(trace_icu_device,
("device=0x%x, base=0x%x, nr_bytes=%d\n",
device, base, nr_bytes));
return cpu_nr(processor);
}
STATIC_INLINE_DEVICES void
icu_write_callback(device_node *device,
unsigned_word base,
unsigned nr_bytes,
unsigned64 val,
cpu *processor,
unsigned_word cia)
{
psim *system = cpu_system(processor);
device_node *parent = device; /* NB: normally would be device->parent */
TRACE(trace_icu_device,
("device=0x%x, base=0x%x, nr_bytes=%d, val=0x%x\n",
device, base, nr_bytes, val));
/* tell the parent device that the interrupt lines have changed.
For this fake ICU. The interrupt lines just indicate the cpu to
interrupt next */
parent->callbacks->interrupt_callback(parent, val, device, processor, cia);
}
STATIC_INLINE_DEVICES void
icu_do_interrupt(event_queue *queue,
void *data)
{
cpu *target = (cpu*)data;
/* try to interrupt the processor. If the attempt fails, try again
on the next tick */
if (!external_interrupt(target))
event_queue_schedule(queue, 1, icu_do_interrupt, target);
}
STATIC_INLINE_DEVICES void
icu_interrupt_callback(device_node *me,
int interrupt_status,
device_node *device,
cpu *processor,
unsigned_word cia)
{
/* the interrupt controler can't interrupt a cpu at any time.
Rather it must synchronize with the system clock before
performing an interrupt on the given processor */
psim *system = cpu_system(processor);
cpu *target = psim_cpu(system, interrupt_status);
if (target != NULL) {
event_queue *events = cpu_event_queue(target);
event_queue_schedule(events, 1, icu_do_interrupt, target);
}
}
static device_callbacks icu_callbacks = {
icu_read_callback,
icu_write_callback,
icu_interrupt_callback,
};
STATIC_INLINE_DEVICES device_node *
icu_create(device_node *parent,
char *name)
{
device_node *device;
unsigned address_base;
unsigned address_flags;
/* extract the two arguments */
parse_device_address(name, &address_base, &address_flags);
/* insert into the device tree along with its address info */
device = device_node_create(parent, name, sequential_device,
&icu_callbacks, 0);
device_node_add_address(device,
address_base,
4,
device_is_read_write_exec,
NULL);
return device;
}
static device_descriptor icu_descriptor = {
"icu",
icu_create,
};
/* HALT device:
With real hardware, the processor operation is normally terminated
through a reset. This device illustrates how a reset device could
be attached to an address */
STATIC_INLINE_DEVICES unsigned64
halt_read_callback(device_node *device,
unsigned_word base,
unsigned nr_bytes,
cpu *processor,
unsigned_word cia)
{
cpu_halt(processor, cia, was_exited, 0);
return 0;
}
STATIC_INLINE_DEVICES void
halt_write_callback(device_node *device,
unsigned_word base,
unsigned nr_bytes,
unsigned64 val,
cpu *processor,
unsigned_word cia)
{
cpu_halt(processor, cia, was_exited, 0);
}
static device_callbacks halt_callbacks = {
halt_read_callback,
halt_write_callback,
};
STATIC_INLINE_DEVICES device_node *
halt_create(device_node *parent,
char *name)
{
device_node *device;
unsigned address_base;
unsigned address_flags;
parse_device_address(name, &address_base, &address_flags);
device = device_node_create(parent, name, other_device,
&halt_callbacks, NULL);
device_node_add_address(device,
address_base,
4,
device_is_read_write_exec,
NULL);
return device;
}
static device_descriptor halt_descriptor = {
"halt",
halt_create,
};
static device_descriptor *devices[] = {
&console_descriptor,
&halt_descriptor,
&icu_descriptor,
NULL,
};
INLINE_DEVICES device_descriptor *
find_device_descriptor(char *name)
{
device_descriptor **device;
int name_len;
char *chp;
chp = strchr(name, '@');
name_len = (chp == NULL ? strlen(name) : chp - name);
for (device = devices; *device != NULL; device++) {
if (strncmp(name, (*device)->name, name_len) == 0
&& ((*device)->name[name_len] == '\0'
|| (*device)->name[name_len] == '@'))
return *device;
}
return NULL;
}
#endif /* _DEVICES_C_ */