/*
* udbg for for zilog scc ports as found on Apple PowerMacs
*
* 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/processor.h>
#include <asm/naca.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pmac_feature.h>
extern u8 real_readb(volatile u8 __iomem *addr);
extern void real_writeb(u8 data, volatile u8 __iomem *addr);
#define SCC_TXRDY 4
#define SCC_RXRDY 1
static volatile u8 __iomem *sccc;
static volatile u8 __iomem *sccd;
static void udbg_scc_putc(unsigned char c)
{
if (sccc) {
while ((in_8(sccc) & SCC_TXRDY) == 0)
;
out_8(sccd, c);
if (c == '\n')
udbg_scc_putc('\r');
}
}
static int udbg_scc_getc_poll(void)
{
if (sccc) {
if ((in_8(sccc) & SCC_RXRDY) != 0)
return in_8(sccd);
else
return -1;
}
return -1;
}
static unsigned char udbg_scc_getc(void)
{
if (sccc) {
while ((in_8(sccc) & SCC_RXRDY) == 0)
;
return in_8(sccd);
}
return 0;
}
static unsigned char scc_inittab[] = {
13, 0, /* set baud rate divisor */
12, 0,
14, 1, /* baud rate gen enable, src=rtxc */
11, 0x50, /* clocks = br gen */
5, 0xea, /* tx 8 bits, assert DTR & RTS */
4, 0x46, /* x16 clock, 1 stop */
3, 0xc1, /* rx enable, 8 bits */
};
void udbg_init_scc(struct device_node *np)
{
u32 *reg;
unsigned long addr;
int i, x;
if (np == NULL)
np = of_find_node_by_name(NULL, "escc");
if (np == NULL || np->parent == NULL)
return;
udbg_printf("found SCC...\n");
/* Get address within mac-io ASIC */
reg = (u32 *)get_property(np, "reg", NULL);
if (reg == NULL)
return;
addr = reg[0];
udbg_printf("local addr: %lx\n", addr);
/* Get address of mac-io PCI itself */
reg = (u32 *)get_property(np->parent, "assigned-addresses", NULL);
if (reg == NULL)
return;
addr += reg[2];
udbg_printf("final addr: %lx\n", addr);
/* Setup for 57600 8N1 */
addr += 0x20;
sccc = (volatile u8 * __iomem) ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
sccc += addr & ~PAGE_MASK;
sccd = sccc + 0x10;
udbg_printf("ioremap result sccc: %p\n", sccc);
mb();
for (i = 20000; i != 0; --i)
x = in_8(sccc);
out_8(sccc, 0x09); /* reset A or B side */
out_8(sccc, 0xc0);
for (i = 0; i < sizeof(scc_inittab); ++i)
out_8(sccc, scc_inittab[i]);
udbg_putc = udbg_scc_putc;
udbg_getc = udbg_scc_getc;
udbg_getc_poll = udbg_scc_getc_poll;
udbg_puts("Hello World !\n");
}
static void udbg_real_scc_putc(unsigned char c)
{
while ((real_readb(sccc) & SCC_TXRDY) == 0)
;
real_writeb(c, sccd);
if (c == '\n')
udbg_real_scc_putc('\r');
}
void udbg_init_pmac_realmode(void)
{
sccc = (volatile u8 __iomem *)0x80013020ul;
sccd = (volatile u8 __iomem *)0x80013030ul;
udbg_putc = udbg_real_scc_putc;
udbg_getc = NULL;
udbg_getc_poll = NULL;
}
