acrn-kernel/arch/ppc/syslib/gen550_dbg.c

180 lines
4.4 KiB
C

/*
* A library of polled 16550 serial routines. These are intended to
* be used to support progress messages, xmon, kgdb, etc. on a
* variety of platforms.
*
* Adapted from lots of code ripped from the arch/ppc/boot/ polled
* 16550 support.
*
* Author: Matt Porter <mporter@mvista.com>
*
* 2002-2003 (c) MontaVista Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
#include <linux/types.h>
#include <linux/serial.h>
#include <linux/tty.h> /* For linux/serial_core.h */
#include <linux/serial_core.h>
#include <linux/serialP.h>
#include <linux/serial_reg.h>
#include <asm/machdep.h>
#include <asm/serial.h>
#include <asm/io.h>
#define SERIAL_BAUD 9600
/* SERIAL_PORT_DFNS is defined in <asm/serial.h> */
#ifndef SERIAL_PORT_DFNS
#define SERIAL_PORT_DFNS
#endif
static struct serial_state rs_table[RS_TABLE_SIZE] = {
SERIAL_PORT_DFNS /* defined in <asm/serial.h> */
};
static void (*serial_outb)(unsigned long, unsigned char);
static unsigned long (*serial_inb)(unsigned long);
static int shift;
unsigned long direct_inb(unsigned long addr)
{
return readb((void __iomem *)addr);
}
void direct_outb(unsigned long addr, unsigned char val)
{
writeb(val, (void __iomem *)addr);
}
unsigned long io_inb(unsigned long port)
{
return inb(port);
}
void io_outb(unsigned long port, unsigned char val)
{
outb(val, port);
}
unsigned long serial_init(int chan, void *ignored)
{
unsigned long com_port;
unsigned char lcr, dlm;
/* We need to find out which type io we're expecting. If it's
* 'SERIAL_IO_PORT', we get an offset from the isa_io_base.
* If it's 'SERIAL_IO_MEM', we can the exact location. -- Tom */
switch (rs_table[chan].io_type) {
case SERIAL_IO_PORT:
com_port = rs_table[chan].port;
serial_outb = io_outb;
serial_inb = io_inb;
break;
case SERIAL_IO_MEM:
com_port = (unsigned long)rs_table[chan].iomem_base;
serial_outb = direct_outb;
serial_inb = direct_inb;
break;
default:
/* We can't deal with it. */
return -1;
}
/* How far apart the registers are. */
shift = rs_table[chan].iomem_reg_shift;
/* save the LCR */
lcr = serial_inb(com_port + (UART_LCR << shift));
/* Access baud rate */
serial_outb(com_port + (UART_LCR << shift), UART_LCR_DLAB);
dlm = serial_inb(com_port + (UART_DLM << shift));
/*
* Test if serial port is unconfigured
* We assume that no-one uses less than 110 baud or
* less than 7 bits per character these days.
* -- paulus.
*/
if ((dlm <= 4) && (lcr & 2)) {
/* port is configured, put the old LCR back */
serial_outb(com_port + (UART_LCR << shift), lcr);
}
else {
/* Input clock. */
serial_outb(com_port + (UART_DLL << shift),
(rs_table[chan].baud_base / SERIAL_BAUD) & 0xFF);
serial_outb(com_port + (UART_DLM << shift),
(rs_table[chan].baud_base / SERIAL_BAUD) >> 8);
/* 8 data, 1 stop, no parity */
serial_outb(com_port + (UART_LCR << shift), 0x03);
/* RTS/DTR */
serial_outb(com_port + (UART_MCR << shift), 0x03);
/* Clear & enable FIFOs */
serial_outb(com_port + (UART_FCR << shift), 0x07);
}
return (com_port);
}
void
serial_putc(unsigned long com_port, unsigned char c)
{
while ((serial_inb(com_port + (UART_LSR << shift)) & UART_LSR_THRE) == 0)
;
serial_outb(com_port, c);
}
unsigned char
serial_getc(unsigned long com_port)
{
while ((serial_inb(com_port + (UART_LSR << shift)) & UART_LSR_DR) == 0)
;
return serial_inb(com_port);
}
int
serial_tstc(unsigned long com_port)
{
return ((serial_inb(com_port + (UART_LSR << shift)) & UART_LSR_DR) != 0);
}
void
serial_close(unsigned long com_port)
{
}
void
gen550_init(int i, struct uart_port *serial_req)
{
rs_table[i].io_type = serial_req->iotype;
rs_table[i].port = serial_req->iobase;
rs_table[i].iomem_base = serial_req->membase;
rs_table[i].iomem_reg_shift = serial_req->regshift;
rs_table[i].baud_base = serial_req->uartclk ? serial_req->uartclk / 16 : BASE_BAUD;
}
#ifdef CONFIG_SERIAL_TEXT_DEBUG
void
gen550_progress(char *s, unsigned short hex)
{
volatile unsigned int progress_debugport;
volatile char c;
progress_debugport = serial_init(0, NULL);
serial_putc(progress_debugport, '\r');
while ((c = *s++) != 0)
serial_putc(progress_debugport, c);
serial_putc(progress_debugport, '\n');
serial_putc(progress_debugport, '\r');
}
#endif /* CONFIG_SERIAL_TEXT_DEBUG */