/*
* udbg for for NS16550 compatable serial ports
*
* Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
*
* 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.
*/
#include <linux/config.h>
#include <linux/types.h>
#include <asm/udbg.h>
#include <asm/io.h>
extern u8 real_readb(volatile u8 __iomem *addr);
extern void real_writeb(u8 data, volatile u8 __iomem *addr);
struct NS16550 {
/* this struct must be packed */
unsigned char rbr; /* 0 */
unsigned char ier; /* 1 */
unsigned char fcr; /* 2 */
unsigned char lcr; /* 3 */
unsigned char mcr; /* 4 */
unsigned char lsr; /* 5 */
unsigned char msr; /* 6 */
unsigned char scr; /* 7 */
};
#define thr rbr
#define iir fcr
#define dll rbr
#define dlm ier
#define dlab lcr
#define LSR_DR 0x01 /* Data ready */
#define LSR_OE 0x02 /* Overrun */
#define LSR_PE 0x04 /* Parity error */
#define LSR_FE 0x08 /* Framing error */
#define LSR_BI 0x10 /* Break */
#define LSR_THRE 0x20 /* Xmit holding register empty */
#define LSR_TEMT 0x40 /* Xmitter empty */
#define LSR_ERR 0x80 /* Error */
static volatile struct NS16550 __iomem *udbg_comport;
static void udbg_550_putc(unsigned char c)
{
if (udbg_comport) {
while ((in_8(&udbg_comport->lsr) & LSR_THRE) == 0)
/* wait for idle */;
out_8(&udbg_comport->thr, c);
if (c == '\n')
udbg_550_putc('\r');
}
}
static int udbg_550_getc_poll(void)
{
if (udbg_comport) {
if ((in_8(&udbg_comport->lsr) & LSR_DR) != 0)
return in_8(&udbg_comport->rbr);
else
return -1;
}
return -1;
}
static unsigned char udbg_550_getc(void)
{
if (udbg_comport) {
while ((in_8(&udbg_comport->lsr) & LSR_DR) == 0)
/* wait for char */;
return in_8(&udbg_comport->rbr);
}
return 0;
}
void udbg_init_uart(void __iomem *comport, unsigned int speed)
{
u16 dll = speed ? (115200 / speed) : 12;
if (comport) {
udbg_comport = (struct NS16550 __iomem *)comport;
out_8(&udbg_comport->lcr, 0x00);
out_8(&udbg_comport->ier, 0xff);
out_8(&udbg_comport->ier, 0x00);
out_8(&udbg_comport->lcr, 0x80); /* Access baud rate */
out_8(&udbg_comport->dll, dll & 0xff); /* 1 = 115200, 2 = 57600,
3 = 38400, 12 = 9600 baud */
out_8(&udbg_comport->dlm, dll >> 8); /* dll >> 8 which should be zero
for fast rates; */
out_8(&udbg_comport->lcr, 0x03); /* 8 data, 1 stop, no parity */
out_8(&udbg_comport->mcr, 0x03); /* RTS/DTR */
out_8(&udbg_comport->fcr ,0x07); /* Clear & enable FIFOs */
udbg_putc = udbg_550_putc;
udbg_getc = udbg_550_getc;
udbg_getc_poll = udbg_550_getc_poll;
}
}
#ifdef CONFIG_PPC_MAPLE
void udbg_maple_real_putc(unsigned char c)
{
if (udbg_comport) {
while ((real_readb(&udbg_comport->lsr) & LSR_THRE) == 0)
/* wait for idle */;
real_writeb(c, &udbg_comport->thr); eieio();
if (c == '\n')
udbg_maple_real_putc('\r');
}
}
void udbg_init_maple_realmode(void)
{
udbg_comport = (volatile struct NS16550 __iomem *)0xf40003f8;
udbg_putc = udbg_maple_real_putc;
udbg_getc = NULL;
udbg_getc_poll = NULL;
}
#endif /* CONFIG_PPC_MAPLE */
