binutils-gdb/sim/lm32/dv-lm32uart.c
Andrew Burgess 1d506c26d9 Update copyright year range in header of all files managed by GDB
This commit is the result of the following actions:

  - Running gdb/copyright.py to update all of the copyright headers to
    include 2024,

  - Manually updating a few files the copyright.py script told me to
    update, these files had copyright headers embedded within the
    file,

  - Regenerating gdbsupport/Makefile.in to refresh it's copyright
    date,

  - Using grep to find other files that still mentioned 2023.  If
    these files were updated last year from 2022 to 2023 then I've
    updated them this year to 2024.

I'm sure I've probably missed some dates.  Feel free to fix them up as
you spot them.
2024-01-12 15:49:57 +00:00

321 lines
7.9 KiB
C

/* Lattice Mico32 UART model.
Contributed by Jon Beniston <jon@beniston.com>
Copyright (C) 2009-2024 Free Software Foundation, Inc.
This file is part of GDB.
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 3 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, see <http://www.gnu.org/licenses/>. */
/* This must come before any other includes. */
#include "defs.h"
#include "sim-main.h"
#include "hw-main.h"
#include "sim-assert.h"
#include <stdio.h>
#include <sys/select.h>
#include <sys/time.h>
struct lm32uart
{
unsigned base; /* Base address of this UART. */
unsigned limit; /* Limit address of this UART. */
unsigned char rbr;
unsigned char thr;
unsigned char ier;
unsigned char iir;
unsigned char lcr;
unsigned char mcr;
unsigned char lsr;
unsigned char msr;
unsigned char div;
struct hw_event *event;
};
/* UART registers. */
#define LM32_UART_RBR 0x0
#define LM32_UART_THR 0x0
#define LM32_UART_IER 0x4
#define LM32_UART_IIR 0x8
#define LM32_UART_LCR 0xc
#define LM32_UART_MCR 0x10
#define LM32_UART_LSR 0x14
#define LM32_UART_MSR 0x18
#define LM32_UART_DIV 0x1c
#define LM32_UART_IER_RX_INT 0x1
#define LM32_UART_IER_TX_INT 0x2
#define MICOUART_IIR_TXRDY 0x2
#define MICOUART_IIR_RXRDY 0x4
#define LM32_UART_LSR_RX_RDY 0x01
#define LM32_UART_LSR_TX_RDY 0x20
#define LM32_UART_LCR_WLS_MASK 0x3
#define LM32_UART_LCR_WLS_5 0x0
#define LM32_UART_LCR_WLS_6 0x1
#define LM32_UART_LCR_WLS_7 0x2
#define LM32_UART_LCR_WLS_8 0x3
/* UART ports. */
enum
{
INT_PORT
};
static const struct hw_port_descriptor lm32uart_ports[] = {
{"int", INT_PORT, 0, output_port},
{}
};
static void
do_uart_tx_event (struct hw *me, void *data)
{
struct lm32uart *uart = hw_data (me);
char c;
/* Generate interrupt when transmission is complete. */
if (uart->ier & LM32_UART_IER_TX_INT)
{
/* Generate interrupt */
hw_port_event (me, INT_PORT, 1);
}
/* Indicate which interrupt has occured. */
uart->iir = MICOUART_IIR_TXRDY;
/* Indicate THR is empty. */
uart->lsr |= LM32_UART_LSR_TX_RDY;
/* Output the character in the THR. */
c = (char) uart->thr;
/* WLS field in LCR register specifies the number of bits to output. */
switch (uart->lcr & LM32_UART_LCR_WLS_MASK)
{
case LM32_UART_LCR_WLS_5:
c &= 0x1f;
break;
case LM32_UART_LCR_WLS_6:
c &= 0x3f;
break;
case LM32_UART_LCR_WLS_7:
c &= 0x7f;
break;
}
printf ("%c", c);
}
static unsigned
lm32uart_io_write_buffer (struct hw *me,
const void *source,
int space, unsigned_word base, unsigned nr_bytes)
{
struct lm32uart *uart = hw_data (me);
int uart_reg;
const unsigned char *source_bytes = source;
int value = 0;
HW_TRACE ((me, "write to 0x%08lx length %d with 0x%x", (long) base,
(int) nr_bytes, value));
if (nr_bytes == 4)
value = (source_bytes[0] << 24)
| (source_bytes[1] << 16) | (source_bytes[2] << 8) | (source_bytes[3]);
else
hw_abort (me, "write of unsupported number of bytes: %d.", nr_bytes);
uart_reg = base - uart->base;
switch (uart_reg)
{
case LM32_UART_THR:
/* Buffer the character to output. */
uart->thr = value;
/* Indicate the THR is full. */
uart->lsr &= ~LM32_UART_LSR_TX_RDY;
/* deassert interrupt when IER is loaded. */
uart->iir &= ~MICOUART_IIR_TXRDY;
/* schedule an event to output the character. */
hw_event_queue_schedule (me, 1, do_uart_tx_event, 0);
break;
case LM32_UART_IER:
uart->ier = value;
if ((value & LM32_UART_IER_TX_INT)
&& (uart->lsr & LM32_UART_LSR_TX_RDY))
{
/* hw_event_queue_schedule (me, 1, do_uart_tx_event, 0); */
uart->lsr |= LM32_UART_LSR_TX_RDY;
uart->iir |= MICOUART_IIR_TXRDY;
hw_port_event (me, INT_PORT, 1);
}
else if ((value & LM32_UART_IER_TX_INT) == 0)
{
hw_port_event (me, INT_PORT, 0);
}
break;
case LM32_UART_IIR:
uart->iir = value;
break;
case LM32_UART_LCR:
uart->lcr = value;
break;
case LM32_UART_MCR:
uart->mcr = value;
break;
case LM32_UART_LSR:
uart->lsr = value;
break;
case LM32_UART_MSR:
uart->msr = value;
break;
case LM32_UART_DIV:
uart->div = value;
break;
default:
hw_abort (me, "write to invalid register address: 0x%x.", uart_reg);
}
return nr_bytes;
}
static unsigned
lm32uart_io_read_buffer (struct hw *me,
void *dest,
int space, unsigned_word base, unsigned nr_bytes)
{
struct lm32uart *uart = hw_data (me);
int uart_reg;
int value;
unsigned char *dest_bytes = dest;
fd_set fd;
struct timeval tv;
HW_TRACE ((me, "read 0x%08lx length %d", (long) base, (int) nr_bytes));
uart_reg = base - uart->base;
switch (uart_reg)
{
case LM32_UART_RBR:
value = getchar ();
uart->lsr &= ~LM32_UART_LSR_RX_RDY;
break;
case LM32_UART_IER:
value = uart->ier;
break;
case LM32_UART_IIR:
value = uart->iir;
break;
case LM32_UART_LCR:
value = uart->lcr;
break;
case LM32_UART_MCR:
value = uart->mcr;
break;
case LM32_UART_LSR:
/* Check to see if any data waiting in stdin. */
FD_ZERO (&fd);
FD_SET (fileno (stdin), &fd);
tv.tv_sec = 0;
tv.tv_usec = 1;
if (select (fileno (stdin) + 1, &fd, NULL, NULL, &tv))
uart->lsr |= LM32_UART_LSR_RX_RDY;
value = uart->lsr;
break;
case LM32_UART_MSR:
value = uart->msr;
break;
case LM32_UART_DIV:
value = uart->div;
break;
default:
hw_abort (me, "read from invalid register address: 0x%x.", uart_reg);
}
if (nr_bytes == 4)
{
dest_bytes[0] = value >> 24;
dest_bytes[1] = value >> 16;
dest_bytes[2] = value >> 8;
dest_bytes[3] = value;
}
else
hw_abort (me, "read of unsupported number of bytes: %d", nr_bytes);
return nr_bytes;
}
static void
attach_lm32uart_regs (struct hw *me, struct lm32uart *uart)
{
unsigned_word attach_address;
int attach_space;
unsigned attach_size;
reg_property_spec reg;
if (hw_find_property (me, "reg") == NULL)
hw_abort (me, "Missing \"reg\" property");
if (!hw_find_reg_array_property (me, "reg", 0, &reg))
hw_abort (me, "\"reg\" property must contain three addr/size entries");
hw_unit_address_to_attach_address (hw_parent (me),
&reg.address,
&attach_space, &attach_address, me);
uart->base = attach_address;
hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
uart->limit = attach_address + (attach_size - 1);
hw_attach_address (hw_parent (me),
0, attach_space, attach_address, attach_size, me);
}
static void
lm32uart_finish (struct hw *me)
{
struct lm32uart *uart;
uart = HW_ZALLOC (me, struct lm32uart);
set_hw_data (me, uart);
set_hw_io_read_buffer (me, lm32uart_io_read_buffer);
set_hw_io_write_buffer (me, lm32uart_io_write_buffer);
set_hw_ports (me, lm32uart_ports);
/* Attach ourself to our parent bus. */
attach_lm32uart_regs (me, uart);
/* Initialize the UART. */
uart->rbr = 0;
uart->thr = 0;
uart->ier = 0;
uart->iir = 0;
uart->lcr = 0;
uart->mcr = 0;
uart->lsr = LM32_UART_LSR_TX_RDY;
uart->msr = 0;
uart->div = 0; /* By setting to zero, characters are output immediately. */
}
const struct hw_descriptor dv_lm32uart_descriptor[] = {
{"lm32uart", lm32uart_finish,},
{NULL},
};