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Diffstat (limited to 'sim/ppc/hw_com.c')
| -rw-r--r-- | sim/ppc/hw_com.c | 559 |
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_ */ |