aboutsummaryrefslogtreecommitdiff
path: root/sim/ppc/hw_com.c
diff options
context:
space:
mode:
Diffstat (limited to 'sim/ppc/hw_com.c')
-rw-r--r--sim/ppc/hw_com.c559
1 files changed, 559 insertions, 0 deletions
diff --git a/sim/ppc/hw_com.c b/sim/ppc/hw_com.c
new file mode 100644
index 0000000..4362322
--- /dev/null
+++ b/sim/ppc/hw_com.c
@@ -0,0 +1,559 @@
+/* This file is part of the program psim.
+
+ Copyright (C) 1994-1996, 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 _HW_COM_C_
+#define _HW_COM_C_
+
+#ifndef STATIC_INLINE_HW_COM
+#define STATIC_INLINE_HW_COM STATIC_INLINE
+#endif
+
+#include "device_table.h"
+
+#ifdef HAVE_STRING_H
+#include <string.h>
+#else
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+#endif
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+
+/* DEVICE
+
+
+ com - '550 compatible serial device
+
+
+ DESCRIPTION
+
+
+ Models the basics of the 8 register '550 serial device. The model
+ includes an interrupt line, input and output fifos, and status
+ information.
+
+ Independent configuration of the devices input and output streams is
+ allowed: use either the console or a file (buffered or unbuffered) as
+ the data source/sink; specify the real-time delay between each character
+ transfer.
+
+ When the devices input stream is being taken from a file, the end of
+ file is signaled by a loss of carrier (the loss of carrier may be
+ incorrectly proceeded by a single null character).
+
+
+ PROPERTIES
+
+
+ reg = <address> <size> ... (optional - note 1)
+
+ List of <address> <size> pairs. Each pair specifies an address for
+ the devices 8 registers. The address should be 8 byte aligned.
+
+
+ alternate-reg = <address> <size> ... (optional - note 1)
+
+ Alternative addreses for the registers.
+
+
+ assigned-addresses = <address> <size> ... (optional - note 1)
+
+ On a PCI bus, this property specifies the addresses assigned to the
+ device. The values reflect the devices configuration base registers.
+
+ Note 1: At least one of "assigned-addresses", "reg" or "alternative-reg"
+ must be specified. If "assigned-addresses" is specified the other
+ address specifications are ignored.
+
+
+ input-file = <file-name> (optional)
+
+ File to take all serial port input from (instead of the simulation
+ console).
+
+
+ output-file = <file-name> (optional)
+
+ File to send all output to (instead of the simulation console).
+
+
+ input-buffering = "unbuffered" (optional)
+
+ Specifying "unbuffered" buffering disables buffering on the serial
+ devices input stream (all data is immediatly read). In the future,
+ this option may be used to provide input buffering alternatives.
+
+
+ output-buffering = "unbuffered" (optional)
+
+ Specifying "unbuffered" buffering disables buffering on the serial
+ devices output stream (all data is immediatly written). In the future,
+ this option may be extended to include other buffering alternatives.
+
+
+ input-delay = <integer-delay> (optional)
+
+ Specify the number of ticks after the current character has been
+ read from the serial port that the next character becomes
+ available.
+
+
+ output-delay = <integer-delay> (optional)
+
+ Specify the number of ticks after a character has been written to
+ the empty output fifo that the fifo finishes draining. Any
+ characters written to the output fifo before it has drained will
+ not be lost and will still be displayed.
+
+
+ EXAMPLES
+
+
+ | /iobus@0xf0000000/com@0x3000/reg 0x3000 8
+
+ Create a simple console device at address <<0x3000>> within
+ <<iobus>>. Since iobus starts at address <<0xf0000000>> the
+ absolute address of the serial port will be <<0xf0003000>>.
+
+ The device will always be ready for I/O (no delay properties specified)
+ and both the input and output streams will use the simulation console
+ (no file properties).
+
+
+ | $ psim \
+ | -o '/cpus/cpu@0' \
+ | -o '/iobus@0xf0000000/com@0x4000/reg 0x4000 8' \
+ | -o '/iobus@0xf0000000/com@0x4000/input-file /etc/passwd' \
+ | -o '/iobus@0xf0000000/com@0x4000/input-delay 1000' \
+ | -o '/iobus@0xf0000000/com@0x4000 > 0 int /cpus/cpu@0x0' \
+ | psim-test/hw-com/cat.be 0xf0004000
+
+ The serial port (at address <<0xf0004000>> is configured so that it
+ takes its input from the file <</etc/passwd>> while its output is
+ allowed to appear on the simulation console.
+
+ The node <</cpus/cpu@0>> was explicitly specified to ensure that it had
+ been created before any interrupts were attached to it.
+
+ The program <<psim-test/hw-com/cat>> copies any characters on the serial
+ port's input (<</etc/passwd>>) to its output (the console).
+ Consequently, the aove program will display the contents of the file
+ <</etc/passwd>> on the screen.
+
+
+ BUGS
+
+
+ IEEE 1275 requires that a device on a PCI bus have, as its first reg
+ entry, the address of its configuration space registers. Currently,
+ this device does not even implement configuration registers.
+
+ This model does not attempt to model the '550's input and output fifos.
+ Instead, the input fifo is limited to a single character at a time,
+ while the output fifo is effectivly infinite. Consequently, unlike the
+ '550, this device will not discard output characters once a stream of 16
+ have been written to the data output register.
+
+ The input and output can only be taken from a file (or the current
+ terminal device). In the future, the <<com>> device should allow the
+ specification of other data streams (such as an xterm or TK window).
+
+ The input blocks if no data is available.
+
+ Interrupts have not been tested.
+
+ */
+
+enum {
+ max_hw_com_registers = 8,
+};
+
+typedef struct _com_port {
+ int ready;
+ int delay;
+ int interrupting;
+ FILE *file;
+} com_port;
+
+typedef struct _com_modem {
+ int carrier;
+ int carrier_changed;
+ int interrupting;
+} com_modem;
+
+typedef struct _hw_com_device {
+ com_port input;
+ com_port output;
+ com_modem modem;
+ char dlab[2];
+ char reg[max_hw_com_registers];
+ int interrupting;
+} hw_com_device;
+
+
+static void
+hw_com_device_init_data(device *me)
+{
+ hw_com_device *com = (hw_com_device*)device_data(me);
+ /* clean up */
+ if (com->output.file != NULL)
+ fclose(com->output.file);
+ if (com->input.file != NULL)
+ fclose(com->input.file);
+ memset(com, 0, sizeof(hw_com_device));
+
+ /* the fifo speed */
+ com->output.delay = (device_find_property(me, "output-delay") != NULL
+ ? device_find_integer_property(me, "output-delay")
+ : 0);
+ com->input.delay = (device_find_property(me, "input-delay") != NULL
+ ? device_find_integer_property(me, "input-delay")
+ : 0);
+
+ /* the data source/sink */
+ if (device_find_property(me, "input-file") != NULL) {
+ const char *input_file = device_find_string_property(me, "input-file");
+ com->input.file = fopen(input_file, "r");
+ if (com->input.file == NULL)
+ device_error(me, "Problem opening input file %s\n", input_file);
+ if (device_find_property(me, "input-buffering") != NULL) {
+ const char *buffering = device_find_string_property(me, "input-buffering");
+ if (strcmp(buffering, "unbuffered") == 0)
+ setbuf(com->input.file, NULL);
+ }
+ }
+ if (device_find_property(me, "output-file") != NULL) {
+ const char *output_file = device_find_string_property(me, "output-file");
+ com->output.file = fopen(output_file, "w");
+ if (com->input.file == NULL)
+ device_error(me, "Problem opening output file %s\n", output_file);
+ if (device_find_property(me, "output-buffering") != NULL) {
+ const char *buffering = device_find_string_property(me, "output-buffering");
+ if (strcmp(buffering, "unbuffered") == 0)
+ setbuf(com->output.file, NULL);
+ }
+ }
+
+ /* ready from the start */
+ com->input.ready = 1;
+ com->modem.carrier = 1;
+ com->output.ready = 1;
+}
+
+
+static void
+update_com_interrupts(device *me,
+ hw_com_device *com)
+{
+ int interrupting;
+ com->modem.interrupting = (com->modem.carrier_changed && (com->reg[1] & 0x80));
+ com->input.interrupting = (com->input.ready && (com->reg[1] & 0x1));
+ com->output.interrupting = (com->output.ready && (com->reg[1] & 0x2));
+ interrupting = (com->input.interrupting
+ || com->output.interrupting
+ || com->modem.interrupting);
+
+ if (interrupting) {
+ if (!com->interrupting) {
+ device_interrupt_event(me, 0 /*port*/, 1 /*value*/, NULL, 0);
+ }
+ }
+ else /*!interrupting*/ {
+ if (com->interrupting)
+ device_interrupt_event(me, 0 /*port*/, 0 /*value*/, NULL, 0);
+ }
+ com->interrupting = interrupting;
+}
+
+
+static void
+make_read_ready(void *data)
+{
+ device *me = (device*)data;
+ hw_com_device *com = (hw_com_device*)device_data(me);
+ com->input.ready = 1;
+ update_com_interrupts(me, com);
+}
+
+static void
+read_com(device *me,
+ hw_com_device *com,
+ unsigned_word a,
+ char val[1])
+{
+ unsigned_word addr = a % 8;
+
+ /* the divisor latch is special */
+ if (com->reg[3] & 0x8 && addr < 2) {
+ *val = com->dlab[addr];
+ return;
+ }
+
+ switch (addr) {
+
+ case 0:
+ /* fifo */
+ if (!com->modem.carrier)
+ *val = '\0';
+ if (com->input.ready) {
+ /* read the char in */
+ if (com->input.file == NULL) {
+ if (sim_io_read_stdin(val, 1) < 0)
+ com->modem.carrier_changed = 1;
+ }
+ else {
+ if (fread(val, 1, 1, com->input.file) == 0)
+ com->modem.carrier_changed = 1;
+ }
+ /* setup for next read */
+ if (com->modem.carrier_changed) {
+ /* once lost carrier, never ready */
+ com->modem.carrier = 0;
+ com->input.ready = 0;
+ *val = '\0';
+ }
+ else if (com->input.delay > 0) {
+ com->input.ready = 0;
+ device_event_queue_schedule(me, com->input.delay, make_read_ready, me);
+ }
+ }
+ else {
+ /* discard it? */
+ /* overflow input fifo? */
+ *val = '\0';
+ }
+ break;
+
+ case 2:
+ /* interrupt ident */
+ if (com->interrupting) {
+ if (com->input.interrupting)
+ *val = 0x4;
+ else if (com->output.interrupting)
+ *val = 0x2;
+ else if (com->modem.interrupting == 0)
+ *val = 0;
+ else
+ device_error(me, "bad elif for interrupts\n");
+ }
+ else
+ *val = 0x1;
+ break;
+
+ case 5:
+ /* line status */
+ *val = ((com->input.ready ? 0x1 : 0)
+ | (com->output.ready ? 0x60 : 0)
+ );
+ break;
+
+ case 6:
+ /* modem status */
+ *val = ((com->modem.carrier_changed ? 0x08 : 0)
+ | (com->modem.carrier ? 0x80 : 0)
+ );
+ com->modem.carrier_changed = 0;
+ break;
+
+ default:
+ *val = com->reg[addr];
+ break;
+
+ }
+ update_com_interrupts(me, com);
+}
+
+static unsigned
+hw_com_io_read_buffer_callback(device *me,
+ void *dest,
+ int space,
+ unsigned_word addr,
+ unsigned nr_bytes,
+ cpu *processor,
+ unsigned_word cia)
+{
+ hw_com_device *com = device_data(me);
+ int i;
+ for (i = 0; i < nr_bytes; i++) {
+ read_com(me, com, addr + i, &((char*)dest)[i]);
+ }
+ return nr_bytes;
+}
+
+
+static void
+make_write_ready(void *data)
+{
+ device *me = (device*)data;
+ hw_com_device *com = (hw_com_device*)device_data(me);
+ com->output.ready = 1;
+ update_com_interrupts(me, com);
+}
+
+static void
+write_com(device *me,
+ hw_com_device *com,
+ unsigned_word a,
+ char val)
+{
+ unsigned_word addr = a % 8;
+
+ /* the divisor latch is special */
+ if (com->reg[3] & 0x8 && addr < 2) {
+ com->dlab[addr] = val;
+ return;
+ }
+
+ switch (addr) {
+
+ case 0:
+ /* fifo */
+ if (com->output.file == NULL) {
+ sim_io_write_stdout(&val, 1);
+ }
+ else {
+ fwrite(&val, 1, 1, com->output.file);
+ }
+ /* setup for next write */
+ if (com->output.ready && com->output.delay > 0) {
+ com->output.ready = 0;
+ device_event_queue_schedule(me, com->output.delay, make_write_ready, me);
+ }
+ break;
+
+ default:
+ com->reg[addr] = val;
+ break;
+
+ }
+ update_com_interrupts(me, com);
+}
+
+static unsigned
+hw_com_io_write_buffer_callback(device *me,
+ const void *source,
+ int space,
+ unsigned_word addr,
+ unsigned nr_bytes,
+ cpu *processor,
+ unsigned_word cia)
+{
+ hw_com_device *com = device_data(me);
+ int i;
+ for (i = 0; i < nr_bytes; i++) {
+ write_com(me, com, addr + i, ((char*)source)[i]);
+ }
+ return nr_bytes;
+}
+
+
+/* instances of the hw_com device */
+
+static void
+hw_com_instance_delete(device_instance *instance)
+{
+ /* nothing to delete, the hw_com is attached to the device */
+ return;
+}
+
+static int
+hw_com_instance_read(device_instance *instance,
+ void *buf,
+ unsigned_word len)
+{
+ device *me = device_instance_device(instance);
+ hw_com_device *com = device_data(me);
+ if (com->input.file == NULL)
+ return sim_io_read_stdin(buf, len);
+ else {
+ return fread(buf, 1, len, com->input.file);
+ }
+}
+
+static int
+hw_com_instance_write(device_instance *instance,
+ const void *buf,
+ unsigned_word len)
+{
+ device *me = device_instance_device(instance);
+ hw_com_device *com = device_data(me);
+ if (com->output.file == NULL)
+ return sim_io_write_stdout(buf, len);
+ else {
+ return fwrite(buf, 1, len, com->output.file);
+ }
+}
+
+static const device_instance_callbacks hw_com_instance_callbacks = {
+ hw_com_instance_delete,
+ hw_com_instance_read,
+ hw_com_instance_write,
+};
+
+static device_instance *
+hw_com_create_instance(device *me,
+ const char *path,
+ const char *args)
+{
+ /* point an instance directly at the device */
+ return device_create_instance_from(me, NULL,
+ device_data(me),
+ path, args,
+ &hw_com_instance_callbacks);
+}
+
+
+static device_callbacks const hw_com_callbacks = {
+ { generic_device_init_address,
+ hw_com_device_init_data },
+ { NULL, }, /* address */
+ { hw_com_io_read_buffer_callback,
+ hw_com_io_write_buffer_callback, },
+ { NULL, }, /* DMA */
+ { NULL, }, /* interrupt */
+ { NULL, }, /* unit */
+ hw_com_create_instance,
+};
+
+
+static void *
+hw_com_create(const char *name,
+ const device_unit *unit_address,
+ const char *args)
+{
+ /* create the descriptor */
+ hw_com_device *hw_com = ZALLOC(hw_com_device);
+ return hw_com;
+}
+
+
+const device_descriptor hw_com_device_descriptor[] = {
+ { "com", hw_com_create, &hw_com_callbacks },
+ { NULL },
+};
+
+#endif /* _HW_COM_C_ */