[linux-2.6-block.git] / arch / powerpc / platforms / powermac / udbg_scc.c

/*
 * udbg 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/types.h>
#include <asm/udbg.h>
#include <asm/processor.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(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 int udbg_scc_getc(void)
{
	if (sccc) {
		while ((in_8(sccc) & SCC_RXRDY) == 0)
			;
		return in_8(sccd);
	}
	return -1;
}

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_scc_init(int force_scc)
{
	const u32 *reg;
	unsigned long addr;
	struct device_node *stdout = NULL, *escc = NULL, *macio = NULL;
	struct device_node *ch, *ch_def = NULL, *ch_a = NULL;
	const char *path;
	int i, x;

	escc = of_find_node_by_name(NULL, "escc");
	if (escc == NULL)
		goto bail;
	macio = of_get_parent(escc);
	if (macio == NULL)
		goto bail;
	path = of_get_property(of_chosen, "linux,stdout-path", NULL);
	if (path != NULL)
		stdout = of_find_node_by_path(path);
	for (ch = NULL; (ch = of_get_next_child(escc, ch)) != NULL;) {
		if (ch == stdout)
			ch_def = of_node_get(ch);
		if (strcmp(ch->name, "ch-a") == 0)
			ch_a = of_node_get(ch);
	}
	if (ch_def == NULL && !force_scc)
		goto bail;

	ch = ch_def ? ch_def : ch_a;

	/* Get address within mac-io ASIC */
	reg = of_get_property(escc, "reg", NULL);
	if (reg == NULL)
		goto bail;
	addr = reg[0];

	/* Get address of mac-io PCI itself */
	reg = of_get_property(macio, "assigned-addresses", NULL);
	if (reg == NULL)
		goto bail;
	addr += reg[2];

	/* Lock the serial port */
	pmac_call_feature(PMAC_FTR_SCC_ENABLE, ch,
			  PMAC_SCC_ASYNC | PMAC_SCC_FLAG_XMON, 1);

	if (ch == ch_a)
		addr += 0x20;
	sccc = ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
	sccc += addr & ~PAGE_MASK;
	sccd = sccc + 0x10;

	mb();

	for (i = 20000; i != 0; --i)
		x = in_8(sccc);
	out_8(sccc, 0x09);		/* reset A or B side */
	out_8(sccc, 0xc0);

	/* If SCC was the OF output port, read the BRG value, else
	 * Setup for 38400 or 57600 8N1 depending on the machine
	 */
	if (ch_def != NULL) {
		out_8(sccc, 13);
		scc_inittab[1] = in_8(sccc);
		out_8(sccc, 12);
		scc_inittab[3] = in_8(sccc);
	} else if (machine_is_compatible("RackMac1,1")
		   || machine_is_compatible("RackMac1,2")
		   || machine_is_compatible("MacRISC4")) {
		/* Xserves and G5s default to 57600 */
		scc_inittab[1] = 0;
		scc_inittab[3] = 0;
	} else {
		/* Others default to 38400 */
		scc_inittab[1] = 0;
		scc_inittab[3] = 1;
	}

	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");

 bail:
	of_node_put(macio);
	of_node_put(escc);
	of_node_put(stdout);
	of_node_put(ch_def);
	of_node_put(ch_a);
}

#ifdef CONFIG_PPC64
static void udbg_real_scc_putc(char c)
{
	while ((real_readb(sccc) & SCC_TXRDY) == 0)
		;
	real_writeb(c, sccd);
	if (c == '\n')
		udbg_real_scc_putc('\r');
}

void __init 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;
}
#endif /* CONFIG_PPC64 */
Commit	Line	Data
7f853352	1	/*
411c9403	2	* udbg for zilog scc ports as found on Apple PowerMacs
7f853352 MM	3	*
	4	* Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
7f853352	11	#include <linux/types.h>
188d2ce7	12	#include <asm/udbg.h>
7f853352	13	#include <asm/processor.h>
7f853352 MM	14	#include <asm/io.h>
	15	#include <asm/prom.h>
	16	#include <asm/pmac_feature.h>
	17
	18	extern u8 real_readb(volatile u8 __iomem *addr);
	19	extern void real_writeb(u8 data, volatile u8 __iomem *addr);
	20
	21	#define SCC_TXRDY 4
	22	#define SCC_RXRDY 1
	23
	24	static volatile u8 __iomem *sccc;
	25	static volatile u8 __iomem *sccd;
	26
51d3082f	27	static void udbg_scc_putc(char c)
7f853352 MM	28	{
	29	if (sccc) {
	30	while ((in_8(sccc) & SCC_TXRDY) == 0)
	31	;
	32	out_8(sccd, c);
	33	if (c == '\n')
	34	udbg_scc_putc('\r');
	35	}
	36	}
	37
	38	static int udbg_scc_getc_poll(void)
	39	{
	40	if (sccc) {
	41	if ((in_8(sccc) & SCC_RXRDY) != 0)
	42	return in_8(sccd);
	43	else
	44	return -1;
	45	}
	46	return -1;
	47	}
	48
bb6b9b28	49	static int udbg_scc_getc(void)
7f853352 MM	50	{
	51	if (sccc) {
	52	while ((in_8(sccc) & SCC_RXRDY) == 0)
	53	;
	54	return in_8(sccd);
	55	}
bb6b9b28	56	return -1;
7f853352 MM	57	}
	58
	59	static unsigned char scc_inittab[] = {
	60	13, 0, /* set baud rate divisor */
	61	12, 0,
	62	14, 1, /* baud rate gen enable, src=rtxc */
	63	11, 0x50, /* clocks = br gen */
	64	5, 0xea, /* tx 8 bits, assert DTR & RTS */
	65	4, 0x46, /* x16 clock, 1 stop */
	66	3, 0xc1, /* rx enable, 8 bits */
	67	};
	68
51d3082f	69	void udbg_scc_init(int force_scc)
7f853352	70	{
018a3d1d	71	const u32 *reg;
7f853352	72	unsigned long addr;
51d3082f BH	73	struct device_node stdout = NULL, escc = NULL, *macio = NULL;
51d3082f BH	74	struct device_node ch, ch_def = NULL, *ch_a = NULL;
018a3d1d	75	const char *path;
7f853352 MM	76	int i, x;
7f853352 MM	77
51d3082f BH	78	escc = of_find_node_by_name(NULL, "escc");
	79	if (escc == NULL)
	80	goto bail;
	81	macio = of_get_parent(escc);
	82	if (macio == NULL)
	83	goto bail;
e2eb6392	84	path = of_get_property(of_chosen, "linux,stdout-path", NULL);
51d3082f BH	85	if (path != NULL)
	86	stdout = of_find_node_by_path(path);
	87	for (ch = NULL; (ch = of_get_next_child(escc, ch)) != NULL;) {
	88	if (ch == stdout)
	89	ch_def = of_node_get(ch);
	90	if (strcmp(ch->name, "ch-a") == 0)
	91	ch_a = of_node_get(ch);
	92	}
	93	if (ch_def == NULL && !force_scc)
	94	goto bail;
	95
	96	ch = ch_def ? ch_def : ch_a;
7f853352	97
7f853352	98	/* Get address within mac-io ASIC */
e2eb6392	99	reg = of_get_property(escc, "reg", NULL);
7f853352	100	if (reg == NULL)
51d3082f	101	goto bail;
7f853352	102	addr = reg[0];
51d3082f	103
7f853352	104	/* Get address of mac-io PCI itself */
e2eb6392	105	reg = of_get_property(macio, "assigned-addresses", NULL);
7f853352	106	if (reg == NULL)
51d3082f	107	goto bail;
7f853352	108	addr += reg[2];
51d3082f BH	109
	110	/* Lock the serial port */
	111	pmac_call_feature(PMAC_FTR_SCC_ENABLE, ch,
	112	PMAC_SCC_ASYNC \| PMAC_SCC_FLAG_XMON, 1);
	113
51d3082f BH	114	if (ch == ch_a)
51d3082f BH	115	addr += 0x20;
af308377	116	sccc = ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
7f853352 MM	117	sccc += addr & ~PAGE_MASK;
	118	sccd = sccc + 0x10;
	119
7f853352 MM	120	mb();
	121
	122	for (i = 20000; i != 0; --i)
	123	x = in_8(sccc);
	124	out_8(sccc, 0x09); /* reset A or B side */
	125	out_8(sccc, 0xc0);
2ec6ef10 BH	126
2ec6ef10 BH	127	/* If SCC was the OF output port, read the BRG value, else
f023bf0f	128	* Setup for 38400 or 57600 8N1 depending on the machine
2ec6ef10 BH	129	*/
	130	if (ch_def != NULL) {
	131	out_8(sccc, 13);
	132	scc_inittab[1] = in_8(sccc);
	133	out_8(sccc, 12);
	134	scc_inittab[3] = in_8(sccc);
f023bf0f BH	135	} else if (machine_is_compatible("RackMac1,1")
	136	\|\| machine_is_compatible("RackMac1,2")
	137	\|\| machine_is_compatible("MacRISC4")) {
	138	/* Xserves and G5s default to 57600 */
	139	scc_inittab[1] = 0;
	140	scc_inittab[3] = 0;
	141	} else {
	142	/* Others default to 38400 */
	143	scc_inittab[1] = 0;
	144	scc_inittab[3] = 1;
2ec6ef10 BH	145	}
2ec6ef10 BH	146
7f853352 MM	147	for (i = 0; i < sizeof(scc_inittab); ++i)
	148	out_8(sccc, scc_inittab[i]);
	149
2ec6ef10	150
c8f1c8be MM	151	udbg_putc = udbg_scc_putc;
	152	udbg_getc = udbg_scc_getc;
	153	udbg_getc_poll = udbg_scc_getc_poll;
7f853352 MM	154
7f853352 MM	155	udbg_puts("Hello World !\n");
51d3082f BH	156
	157	bail:
	158	of_node_put(macio);
	159	of_node_put(escc);
	160	of_node_put(stdout);
	161	of_node_put(ch_def);
	162	of_node_put(ch_a);
7f853352 MM	163	}
7f853352 MM	164
51d3082f BH	165	#ifdef CONFIG_PPC64
51d3082f BH	166	static void udbg_real_scc_putc(char c)
7f853352 MM	167	{
	168	while ((real_readb(sccc) & SCC_TXRDY) == 0)
	169	;
	170	real_writeb(c, sccd);
	171	if (c == '\n')
	172	udbg_real_scc_putc('\r');
	173	}
	174
296167ae	175	void __init udbg_init_pmac_realmode(void)
7f853352 MM	176	{
	177	sccc = (volatile u8 __iomem *)0x80013020ul;
	178	sccd = (volatile u8 __iomem *)0x80013030ul;
	179
c8f1c8be MM	180	udbg_putc = udbg_real_scc_putc;
	181	udbg_getc = NULL;
	182	udbg_getc_poll = NULL;
7f853352	183	}
51d3082f	184	#endif /* CONFIG_PPC64 */