grub-lakitu/grub-core/term/ns8250.c - cos/cobble - Git at Google

 /*
  *  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/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>
 #include <grub/time.h>
 #include <grub/i18n.h>

 #ifdef GRUB_MACHINE_PCBIOS
 #include <grub/machine/memory.h>
 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

 static int dead_ports = 0;

 #ifdef GRUB_MACHINE_MIPS_LOONGSON
 #define DEFAULT_BASE_CLOCK (2 * 115200)
 #else
 #define DEFAULT_BASE_CLOCK 115200
 #endif


 /* Convert speed to divisor.  */
 static unsigned short
 serial_get_divisor (const struct grub_serial_port *port __attribute__ ((unused)),
 		    const struct grub_serial_config *config)
 {
   grub_uint32_t base_clock;
   grub_uint32_t divisor;
   grub_uint32_t actual_speed, error;

   base_clock = config->base_clock ? (config->base_clock >> 4) : DEFAULT_BASE_CLOCK;

   divisor = (base_clock + (config->speed / 2)) / config->speed;
   if (config->speed == 0)
     return 0;
   if (divisor > 0xffff || divisor == 0)
     return 0;
   actual_speed = base_clock / divisor;
   error = actual_speed > config->speed ? (actual_speed - config->speed)
     : (config->speed - actual_speed);
   if (error > (config->speed / 30 + 1))
     return 0;
   return divisor;
 }

 static void
 do_real_config (struct grub_serial_port *port)
 {
   int divisor;
   unsigned char status = 0;
   grub_uint64_t endtime;

   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;

   port->broken = 0;

   divisor = serial_get_divisor (port, &port->config);

   /* 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);

   if (port->config.rtscts)
     {
       /* 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);
     }

   /* Drain the input buffer.  */
   endtime = grub_get_time_ms () + 1000;
   while (grub_inb (port->port + UART_LSR) & UART_DATA_READY)
     {
       grub_inb (port->port + UART_RX);
       if (grub_get_time_ms () > endtime)
 	{
 	  port->broken = 1;
 	  break;
 	}
     }

   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)
 {
   grub_uint64_t endtime;

   do_real_config (port);

   if (port->broken > 5)
     endtime = grub_get_time_ms ();
   else if (port->broken > 1)
     endtime = grub_get_time_ms () + 50;
   else
     endtime = grub_get_time_ms () + 200;
   /* Wait until the transmitter holding register is empty.  */
   while ((grub_inb (port->port + UART_LSR) & UART_EMPTY_TRANSMITTER) == 0)
     {
       if (grub_get_time_ms () > endtime)
 	{
 	  port->broken++;
 	  /* There is something wrong. But what can I do?  */
 	  return;
 	}
     }

   if (port->broken)
     port->broken--;

   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 (port, config);
   if (divisor == 0)
     return grub_error (GRUB_ERR_BAD_ARGUMENT,
 		       N_("unsupported serial port 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,
 		       N_("unsupported serial port 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,
 		       N_("unsupported serial port stop bits number"));

   if (config->word_len < 5 || config->word_len > 8)
     return grub_error (GRUB_ERR_BAD_ARGUMENT,
 		       N_("unsupported serial port word length"));

   port->config = *config;
   port->configured = 0;

   /*  FIXME: should check if the serial terminal was found.  */

   return GRUB_ERR_NONE;
 }

 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)
 {
   unsigned i;
   for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
     if (serial_hw_io_addr[i])
       {
 	grub_err_t err;

 	grub_outb (0x5a, serial_hw_io_addr[i] + UART_SR);
 	if (grub_inb (serial_hw_io_addr[i] + UART_SR) != 0x5a)
 	  {
 	    dead_ports |= (1 << i);
 	    continue;
 	  }
 	grub_outb (0xa5, serial_hw_io_addr[i] + UART_SR);
 	if (grub_inb (serial_hw_io_addr[i] + UART_SR) != 0xa5)
 	  {
 	    dead_ports |= (1 << i);
 	    continue;
 	  }

 	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]);
       }
 }

 /* Return the port number for the UNITth serial device.  */
 grub_port_t
 grub_ns8250_hw_get_port (const unsigned int unit)
 {
   if (unit < GRUB_SERIAL_PORT_NUM
       && !(dead_ports & (1 << unit)))
     return serial_hw_io_addr[unit];
   else
     return 0;
 }

 char *
 grub_serial_ns8250_add_port (grub_port_t port)
 {
   struct grub_serial_port *p;
   unsigned i;
   for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
     if (com_ports[i].port == port)
       {
 	if (dead_ports & (1 << i))
 	  return NULL;
 	return com_names[i];
       }

   grub_outb (0x5a, port + UART_SR);
   if (grub_inb (port + UART_SR) != 0x5a)
     return NULL;

   grub_outb (0xa5, port + UART_SR);
   if (grub_inb (port + UART_SR) != 0xa5)
     return NULL;

   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;
 }
	/*
	* 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/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>
	#include <grub/time.h>
	#include <grub/i18n.h>

	#ifdef GRUB_MACHINE_PCBIOS
	#include <grub/machine/memory.h>
	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

	static int dead_ports = 0;

	#ifdef GRUB_MACHINE_MIPS_LOONGSON
	#define DEFAULT_BASE_CLOCK (2 * 115200)
	#else
	#define DEFAULT_BASE_CLOCK 115200
	#endif


	/* Convert speed to divisor. */
	static unsigned short
	serial_get_divisor (const struct grub_serial_port *port __attribute__ ((unused)),
	const struct grub_serial_config *config)
	{
	grub_uint32_t base_clock;
	grub_uint32_t divisor;
	grub_uint32_t actual_speed, error;

	base_clock = config->base_clock ? (config->base_clock >> 4) : DEFAULT_BASE_CLOCK;

	divisor = (base_clock + (config->speed / 2)) / config->speed;
	if (config->speed == 0)
	return 0;
	if (divisor > 0xffff \|\| divisor == 0)
	return 0;
	actual_speed = base_clock / divisor;
	error = actual_speed > config->speed ? (actual_speed - config->speed)
	: (config->speed - actual_speed);
	if (error > (config->speed / 30 + 1))
	return 0;
	return divisor;
	}

	static void
	do_real_config (struct grub_serial_port *port)
	{
	int divisor;
	unsigned char status = 0;
	grub_uint64_t endtime;

	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;

	port->broken = 0;

	divisor = serial_get_divisor (port, &port->config);

	/* 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);

	if (port->config.rtscts)
	{
	/* 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);
	}

	/* Drain the input buffer. */
	endtime = grub_get_time_ms () + 1000;
	while (grub_inb (port->port + UART_LSR) & UART_DATA_READY)
	{
	grub_inb (port->port + UART_RX);
	if (grub_get_time_ms () > endtime)
	{
	port->broken = 1;
	break;
	}
	}

	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)
	{
	grub_uint64_t endtime;

	do_real_config (port);

	if (port->broken > 5)
	endtime = grub_get_time_ms ();
	else if (port->broken > 1)
	endtime = grub_get_time_ms () + 50;
	else
	endtime = grub_get_time_ms () + 200;
	/* Wait until the transmitter holding register is empty. */
	while ((grub_inb (port->port + UART_LSR) & UART_EMPTY_TRANSMITTER) == 0)
	{
	if (grub_get_time_ms () > endtime)
	{
	port->broken++;
	/* There is something wrong. But what can I do? */
	return;
	}
	}

	if (port->broken)
	port->broken--;

	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 (port, config);
	if (divisor == 0)
	return grub_error (GRUB_ERR_BAD_ARGUMENT,
	N_("unsupported serial port 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,
	N_("unsupported serial port 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,
	N_("unsupported serial port stop bits number"));

	if (config->word_len < 5 \|\| config->word_len > 8)
	return grub_error (GRUB_ERR_BAD_ARGUMENT,
	N_("unsupported serial port word length"));

	port->config = *config;
	port->configured = 0;

	/* FIXME: should check if the serial terminal was found. */

	return GRUB_ERR_NONE;
	}

	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)
	{
	unsigned i;
	for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
	if (serial_hw_io_addr[i])
	{
	grub_err_t err;

	grub_outb (0x5a, serial_hw_io_addr[i] + UART_SR);
	if (grub_inb (serial_hw_io_addr[i] + UART_SR) != 0x5a)
	{
	dead_ports \|= (1 << i);
	continue;
	}
	grub_outb (0xa5, serial_hw_io_addr[i] + UART_SR);
	if (grub_inb (serial_hw_io_addr[i] + UART_SR) != 0xa5)
	{
	dead_ports \|= (1 << i);
	continue;
	}

	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]);
	}
	}

	/* Return the port number for the UNITth serial device. */
	grub_port_t
	grub_ns8250_hw_get_port (const unsigned int unit)
	{
	if (unit < GRUB_SERIAL_PORT_NUM
	&& !(dead_ports & (1 << unit)))
	return serial_hw_io_addr[unit];
	else
	return 0;
	}

	char *
	grub_serial_ns8250_add_port (grub_port_t port)
	{
	struct grub_serial_port *p;
	unsigned i;
	for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
	if (com_ports[i].port == port)
	{
	if (dead_ports & (1 << i))
	return NULL;
	return com_names[i];
	}

	grub_outb (0x5a, port + UART_SR);
	if (grub_inb (port + UART_SR) != 0x5a)
	return NULL;

	grub_outb (0xa5, port + UART_SR);
	if (grub_inb (port + UART_SR) != 0xa5)
	return NULL;

	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;
	}