253 lines
7 KiB
C
253 lines
7 KiB
C
/*
|
|
* GRUB -- GRand Unified Bootloader
|
|
* Copyright (C) 2000,2001,2002,2003,2004,2005,2007,2008,2009,2010 Free Software Foundation, Inc.
|
|
*
|
|
* GRUB 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.
|
|
*
|
|
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <grub/machine/memory.h>
|
|
#include <grub/serial.h>
|
|
#include <grub/ns8250.h>
|
|
#include <grub/types.h>
|
|
#include <grub/dl.h>
|
|
#include <grub/misc.h>
|
|
#include <grub/cpu/io.h>
|
|
#include <grub/mm.h>
|
|
|
|
#ifdef GRUB_MACHINE_PCBIOS
|
|
static const unsigned short *serial_hw_io_addr = (const unsigned short *) GRUB_MEMORY_MACHINE_BIOS_DATA_AREA_ADDR;
|
|
#define GRUB_SERIAL_PORT_NUM 4
|
|
#else
|
|
#include <grub/machine/serial.h>
|
|
static const grub_port_t serial_hw_io_addr[] = GRUB_MACHINE_SERIAL_PORTS;
|
|
#define GRUB_SERIAL_PORT_NUM (ARRAY_SIZE(serial_hw_io_addr))
|
|
#endif
|
|
|
|
/* Convert speed to divisor. */
|
|
static unsigned short
|
|
serial_get_divisor (unsigned int speed)
|
|
{
|
|
unsigned int i;
|
|
|
|
/* The structure for speed vs. divisor. */
|
|
struct divisor
|
|
{
|
|
unsigned int speed;
|
|
unsigned short div;
|
|
};
|
|
|
|
/* The table which lists common configurations. */
|
|
/* 1843200 / (speed * 16) */
|
|
static struct divisor divisor_tab[] =
|
|
{
|
|
{ 2400, 0x0030 },
|
|
{ 4800, 0x0018 },
|
|
{ 9600, 0x000C },
|
|
{ 19200, 0x0006 },
|
|
{ 38400, 0x0003 },
|
|
{ 57600, 0x0002 },
|
|
{ 115200, 0x0001 }
|
|
};
|
|
|
|
/* Set the baud rate. */
|
|
for (i = 0; i < ARRAY_SIZE (divisor_tab); i++)
|
|
if (divisor_tab[i].speed == speed)
|
|
/* UART in Yeeloong runs twice the usual rate. */
|
|
#ifdef GRUB_MACHINE_MIPS_YEELOONG
|
|
return 2 * divisor_tab[i].div;
|
|
#else
|
|
return divisor_tab[i].div;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
do_real_config (struct grub_serial_port *port)
|
|
{
|
|
int divisor;
|
|
unsigned char status = 0;
|
|
const unsigned char parities[] = {
|
|
[GRUB_SERIAL_PARITY_NONE] = UART_NO_PARITY,
|
|
[GRUB_SERIAL_PARITY_ODD] = UART_ODD_PARITY,
|
|
[GRUB_SERIAL_PARITY_EVEN] = UART_EVEN_PARITY
|
|
};
|
|
const unsigned char stop_bits[] = {
|
|
[GRUB_SERIAL_STOP_BITS_1] = UART_1_STOP_BIT,
|
|
[GRUB_SERIAL_STOP_BITS_2] = UART_2_STOP_BITS,
|
|
};
|
|
|
|
if (port->configured)
|
|
return;
|
|
|
|
divisor = serial_get_divisor (port->config.speed);
|
|
|
|
/* Turn off the interrupt. */
|
|
grub_outb (0, port->port + UART_IER);
|
|
|
|
/* Set DLAB. */
|
|
grub_outb (UART_DLAB, port->port + UART_LCR);
|
|
|
|
/* Set the baud rate. */
|
|
grub_outb (divisor & 0xFF, port->port + UART_DLL);
|
|
grub_outb (divisor >> 8, port->port + UART_DLH);
|
|
|
|
/* Set the line status. */
|
|
status |= (parities[port->config.parity]
|
|
| (port->config.word_len - 5)
|
|
| stop_bits[port->config.stop_bits]);
|
|
grub_outb (status, port->port + UART_LCR);
|
|
|
|
/* In Yeeloong serial port has only 3 wires. */
|
|
#ifndef GRUB_MACHINE_MIPS_YEELOONG
|
|
/* Enable the FIFO. */
|
|
grub_outb (UART_ENABLE_FIFO_TRIGGER1, port->port + UART_FCR);
|
|
|
|
/* Turn on DTR and RTS. */
|
|
grub_outb (UART_ENABLE_DTRRTS, port->port + UART_MCR);
|
|
#else
|
|
/* Enable the FIFO. */
|
|
grub_outb (UART_ENABLE_FIFO_TRIGGER14, port->port + UART_FCR);
|
|
|
|
/* Turn on DTR, RTS, and OUT2. */
|
|
grub_outb (UART_ENABLE_DTRRTS | UART_ENABLE_OUT2, port->port + UART_MCR);
|
|
#endif
|
|
|
|
/* Drain the input buffer. */
|
|
while (grub_inb (port->port + UART_LSR) & UART_DATA_READY)
|
|
grub_inb (port->port + UART_RX);
|
|
|
|
port->configured = 1;
|
|
}
|
|
|
|
/* Fetch a key. */
|
|
static int
|
|
serial_hw_fetch (struct grub_serial_port *port)
|
|
{
|
|
do_real_config (port);
|
|
if (grub_inb (port->port + UART_LSR) & UART_DATA_READY)
|
|
return grub_inb (port->port + UART_RX);
|
|
|
|
return -1;
|
|
}
|
|
|
|
/* Put a character. */
|
|
static void
|
|
serial_hw_put (struct grub_serial_port *port, const int c)
|
|
{
|
|
unsigned int timeout = 100000;
|
|
|
|
do_real_config (port);
|
|
|
|
/* Wait until the transmitter holding register is empty. */
|
|
while ((grub_inb (port->port + UART_LSR) & UART_EMPTY_TRANSMITTER) == 0)
|
|
{
|
|
if (--timeout == 0)
|
|
/* There is something wrong. But what can I do? */
|
|
return;
|
|
}
|
|
|
|
grub_outb (c, port->port + UART_TX);
|
|
}
|
|
|
|
/* Initialize a serial device. PORT is the port number for a serial device.
|
|
SPEED is a DTE-DTE speed which must be one of these: 2400, 4800, 9600,
|
|
19200, 38400, 57600 and 115200. WORD_LEN is the word length to be used
|
|
for the device. Likewise, PARITY is the type of the parity and
|
|
STOP_BIT_LEN is the length of the stop bit. The possible values for
|
|
WORD_LEN, PARITY and STOP_BIT_LEN are defined in the header file as
|
|
macros. */
|
|
static grub_err_t
|
|
serial_hw_configure (struct grub_serial_port *port,
|
|
struct grub_serial_config *config)
|
|
{
|
|
unsigned short divisor;
|
|
|
|
divisor = serial_get_divisor (config->speed);
|
|
if (divisor == 0)
|
|
return grub_error (GRUB_ERR_BAD_ARGUMENT, "bad speed");
|
|
|
|
if (config->parity != GRUB_SERIAL_PARITY_NONE
|
|
&& config->parity != GRUB_SERIAL_PARITY_ODD
|
|
&& config->parity != GRUB_SERIAL_PARITY_EVEN)
|
|
return grub_error (GRUB_ERR_BAD_ARGUMENT, "unsupported parity");
|
|
|
|
if (config->stop_bits != GRUB_SERIAL_STOP_BITS_1
|
|
&& config->stop_bits != GRUB_SERIAL_STOP_BITS_2)
|
|
return grub_error (GRUB_ERR_BAD_ARGUMENT, "unsupported stop bits");
|
|
|
|
if (config->word_len < 5 || config->word_len > 8)
|
|
return grub_error (GRUB_ERR_BAD_ARGUMENT, "unsupported word length");
|
|
|
|
port->config = *config;
|
|
port->configured = 0;
|
|
|
|
/* FIXME: should check if the serial terminal was found. */
|
|
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
|
|
static struct grub_serial_driver grub_ns8250_driver =
|
|
{
|
|
.configure = serial_hw_configure,
|
|
.fetch = serial_hw_fetch,
|
|
.put = serial_hw_put
|
|
};
|
|
|
|
static char com_names[GRUB_SERIAL_PORT_NUM][20];
|
|
static struct grub_serial_port com_ports[GRUB_SERIAL_PORT_NUM];
|
|
|
|
void
|
|
grub_ns8250_init (void)
|
|
{
|
|
int i;
|
|
for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
|
|
if (serial_hw_io_addr[i])
|
|
{
|
|
grub_err_t err;
|
|
grub_snprintf (com_names[i], sizeof (com_names[i]), "com%d", i);
|
|
com_ports[i].name = com_names[i];
|
|
com_ports[i].driver = &grub_ns8250_driver;
|
|
com_ports[i].port = serial_hw_io_addr[i];
|
|
err = grub_serial_config_defaults (&com_ports[i]);
|
|
if (err)
|
|
grub_print_error ();
|
|
|
|
grub_serial_register (&com_ports[i]);
|
|
}
|
|
}
|
|
|
|
char *
|
|
grub_serial_ns8250_add_port (grub_port_t port)
|
|
{
|
|
struct grub_serial_port *p;
|
|
int i;
|
|
for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
|
|
if (com_ports[i].port == port)
|
|
return com_names[i];
|
|
p = grub_malloc (sizeof (*p));
|
|
if (!p)
|
|
return NULL;
|
|
p->name = grub_xasprintf ("port%lx", (unsigned long) port);
|
|
if (!p->name)
|
|
{
|
|
grub_free (p);
|
|
return NULL;
|
|
}
|
|
p->driver = &grub_ns8250_driver;
|
|
grub_serial_config_defaults (p);
|
|
p->port = port;
|
|
grub_serial_register (p);
|
|
|
|
return p->name;
|
|
}
|