arch/ppc/xmon/start.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (C) 1996 Paul Mackerras.
  */
 #include <linux/config.h>
 #include <linux/string.h>
 #include <asm/machdep.h>
 #include <asm/io.h>
 #include <asm/page.h>
 #include <linux/adb.h>
 #include <linux/pmu.h>
 #include <linux/cuda.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/sysrq.h>
 #include <linux/bitops.h>
 #include <asm/xmon.h>
 #include <asm/prom.h>
 #include <asm/bootx.h>
 #include <asm/machdep.h>
 #include <asm/errno.h>
 #include <asm/pmac_feature.h>
 #include <asm/processor.h>
 #include <asm/delay.h>
 #include <asm/btext.h>

 static volatile unsigned char *sccc, *sccd;
 unsigned int TXRDY, RXRDY, DLAB;
 static int xmon_expect(const char *str, unsigned int timeout);

 static int use_serial;
 static int use_screen;
 static int via_modem;
 static int xmon_use_sccb;
 static struct device_node *channel_node;

 #define TB_SPEED	25000000

 static inline unsigned int readtb(void)
 {
 	unsigned int ret;

 	asm volatile("mftb %0" : "=r" (ret) :);
 	return ret;
 }

 void buf_access(void)
 {
 	if (DLAB)
 		sccd[3] &= ~DLAB;	/* reset DLAB */
 }

 extern int adb_init(void);

 #ifdef CONFIG_PPC_CHRP
 /*
  * This looks in the "ranges" property for the primary PCI host bridge
  * to find the physical address of the start of PCI/ISA I/O space.
  * It is basically a cut-down version of pci_process_bridge_OF_ranges.
  */
 static unsigned long chrp_find_phys_io_base(void)
 {
 	struct device_node *node;
 	unsigned int *ranges;
 	unsigned long base = CHRP_ISA_IO_BASE;
 	int rlen = 0;
 	int np;

 	node = find_devices("isa");
 	if (node != NULL) {
 		node = node->parent;
 		if (node == NULL || node->type == NULL
 		    || strcmp(node->type, "pci") != 0)
 			node = NULL;
 	}
 	if (node == NULL)
 		node = find_devices("pci");
 	if (node == NULL)
 		return base;

 	ranges = (unsigned int *) get_property(node, "ranges", &rlen);
 	np = prom_n_addr_cells(node) + 5;
 	while ((rlen -= np * sizeof(unsigned int)) >= 0) {
 		if ((ranges[0] >> 24) == 1 && ranges[2] == 0) {
 			/* I/O space starting at 0, grab the phys base */
 			base = ranges[np - 3];
 			break;
 		}
 		ranges += np;
 	}
 	return base;
 }
 #endif /* CONFIG_PPC_CHRP */

 #ifdef CONFIG_MAGIC_SYSRQ
 static void sysrq_handle_xmon(int key, struct pt_regs *regs,
 			      struct tty_struct *tty)
 {
 	xmon(regs);
 }

 static struct sysrq_key_op sysrq_xmon_op =
 {
 	.handler =	sysrq_handle_xmon,
 	.help_msg =	"Xmon",
 	.action_msg =	"Entering xmon",
 };
 #endif

 void
 xmon_map_scc(void)
 {
 #ifdef CONFIG_PPC_MULTIPLATFORM
 	volatile unsigned char *base;

 	if (_machine == _MACH_Pmac) {
 		struct device_node *np;
 		unsigned long addr;
 #ifdef CONFIG_BOOTX_TEXT
 		if (!use_screen && !use_serial
 		    && !machine_is_compatible("iMac")) {
 			/* see if there is a keyboard in the device tree
 			   with a parent of type "adb" */
 			for (np = find_devices("keyboard"); np; np = np->next)
 				if (np->parent && np->parent->type
 				    && strcmp(np->parent->type, "adb") == 0)
 					break;

 			/* needs to be hacked if xmon_printk is to be used
 			   from within find_via_pmu() */
 #ifdef CONFIG_ADB_PMU
 			if (np != NULL && boot_text_mapped && find_via_pmu())
 				use_screen = 1;
 #endif
 #ifdef CONFIG_ADB_CUDA
 			if (np != NULL && boot_text_mapped && find_via_cuda())
 				use_screen = 1;
 #endif
 		}
 		if (!use_screen && (np = find_devices("escc")) != NULL) {
 			/*
 			 * look for the device node for the serial port
 			 * we're using and see if it says it has a modem
 			 */
 			char *name = xmon_use_sccb? "ch-b": "ch-a";
 			char *slots;
 			int l;

 			np = np->child;
 			while (np != NULL && strcmp(np->name, name) != 0)
 				np = np->sibling;
 			if (np != NULL) {
 				/* XXX should parse this properly */
 				channel_node = np;
 				slots = get_property(np, "slot-names", &l);
 				if (slots != NULL && l >= 10
 				    && strcmp(slots+4, "Modem") == 0)
 					via_modem = 1;
 			}
 		}
 		btext_drawstring("xmon uses ");
 		if (use_screen)
 			btext_drawstring("screen and keyboard\n");
 		else {
 			if (via_modem)
 				btext_drawstring("modem on ");
 			btext_drawstring(xmon_use_sccb? "printer": "modem");
 			btext_drawstring(" port\n");
 		}

 #endif /* CONFIG_BOOTX_TEXT */

 #ifdef CHRP_ESCC
 		addr = 0xc1013020;
 #else
 		addr = 0xf3013020;
 #endif
 		TXRDY = 4;
 		RXRDY = 1;

 		np = find_devices("mac-io");
 		if (np && np->n_addrs)
 			addr = np->addrs[0].address + 0x13020;
 		base = (volatile unsigned char *) ioremap(addr & PAGE_MASK, PAGE_SIZE);
 		sccc = base + (addr & ~PAGE_MASK);
 		sccd = sccc + 0x10;

 	} else {
 		base = (volatile unsigned char *) isa_io_base;
 		if (_machine == _MACH_chrp)
 			base = (volatile unsigned char *)
 				ioremap(chrp_find_phys_io_base(), 0x1000);

 		sccc = base + 0x3fd;
 		sccd = base + 0x3f8;
 		if (xmon_use_sccb) {
 			sccc -= 0x100;
 			sccd -= 0x100;
 		}
 		TXRDY = 0x20;
 		RXRDY = 1;
 		DLAB = 0x80;
 	}
 #elif defined(CONFIG_GEMINI)
 	/* should already be mapped by the kernel boot */
 	sccc = (volatile unsigned char *) 0xffeffb0d;
 	sccd = (volatile unsigned char *) 0xffeffb08;
 	TXRDY = 0x20;
 	RXRDY = 1;
 	DLAB = 0x80;
 #elif defined(CONFIG_405GP)
 	sccc = (volatile unsigned char *)0xef600305;
 	sccd = (volatile unsigned char *)0xef600300;
 	TXRDY = 0x20;
 	RXRDY = 1;
 	DLAB = 0x80;
 #endif /* platform */

 	register_sysrq_key('x', &sysrq_xmon_op);
 }

 static int scc_initialized = 0;

 void xmon_init_scc(void);
 extern void cuda_poll(void);

 static inline void do_poll_adb(void)
 {
 #ifdef CONFIG_ADB_PMU
 	if (sys_ctrler == SYS_CTRLER_PMU)
 		pmu_poll_adb();
 #endif /* CONFIG_ADB_PMU */
 #ifdef CONFIG_ADB_CUDA
 	if (sys_ctrler == SYS_CTRLER_CUDA)
 		cuda_poll();
 #endif /* CONFIG_ADB_CUDA */
 }

 int
 xmon_write(void *handle, void *ptr, int nb)
 {
 	char *p = ptr;
 	int i, c, ct;

 #ifdef CONFIG_SMP
 	static unsigned long xmon_write_lock;
 	int lock_wait = 1000000;
 	int locked;

 	while ((locked = test_and_set_bit(0, &xmon_write_lock)) != 0)
 		if (--lock_wait == 0)
 			break;
 #endif

 #ifdef CONFIG_BOOTX_TEXT
 	if (use_screen) {
 		/* write it on the screen */
 		for (i = 0; i < nb; ++i)
 			btext_drawchar(*p++);
 		goto out;
 	}
 #endif
 	if (!scc_initialized)
 		xmon_init_scc();
 	ct = 0;
 	for (i = 0; i < nb; ++i) {
 		while ((*sccc & TXRDY) == 0)
 			do_poll_adb();
 		c = p[i];
 		if (c == '\n' && !ct) {
 			c = '\r';
 			ct = 1;
 			--i;
 		} else {
 			ct = 0;
 		}
 		buf_access();
 		*sccd = c;
 		eieio();
 	}

  out:
 #ifdef CONFIG_SMP
 	if (!locked)
 		clear_bit(0, &xmon_write_lock);
 #endif
 	return nb;
 }

 int xmon_wants_key;
 int xmon_adb_keycode;

 #ifdef CONFIG_BOOTX_TEXT
 static int xmon_adb_shiftstate;

 static unsigned char xmon_keytab[128] =
 	"asdfhgzxcv\000bqwer"				/* 0x00 - 0x0f */
 	"yt123465=97-80]o"				/* 0x10 - 0x1f */
 	"u[ip\rlj'k;\\,/nm."				/* 0x20 - 0x2f */
 	"\t `\177\0\033\0\0\0\0\0\0\0\0\0\0"		/* 0x30 - 0x3f */
 	"\0.\0*\0+\0\0\0\0\0/\r\0-\0"			/* 0x40 - 0x4f */
 	"\0\0000123456789\0\0\0";			/* 0x50 - 0x5f */

 static unsigned char xmon_shift_keytab[128] =
 	"ASDFHGZXCV\000BQWER"				/* 0x00 - 0x0f */
 	"YT!@#$^%+(&_*)}O"				/* 0x10 - 0x1f */
 	"U{IP\rLJ\"K:|<?NM>"				/* 0x20 - 0x2f */
 	"\t ~\177\0\033\0\0\0\0\0\0\0\0\0\0"		/* 0x30 - 0x3f */
 	"\0.\0*\0+\0\0\0\0\0/\r\0-\0"			/* 0x40 - 0x4f */
 	"\0\0000123456789\0\0\0";			/* 0x50 - 0x5f */

 static int
 xmon_get_adb_key(void)
 {
 	int k, t, on;

 	xmon_wants_key = 1;
 	for (;;) {
 		xmon_adb_keycode = -1;
 		t = 0;
 		on = 0;
 		do {
 			if (--t < 0) {
 				on = 1 - on;
 				btext_drawchar(on? 0xdb: 0x20);
 				btext_drawchar('\b');
 				t = 200000;
 			}
 			do_poll_adb();
 		} while (xmon_adb_keycode == -1);
 		k = xmon_adb_keycode;
 		if (on)
 			btext_drawstring(" \b");

 		/* test for shift keys */
 		if ((k & 0x7f) == 0x38 || (k & 0x7f) == 0x7b) {
 			xmon_adb_shiftstate = (k & 0x80) == 0;
 			continue;
 		}
 		if (k >= 0x80)
 			continue;	/* ignore up transitions */
 		k = (xmon_adb_shiftstate? xmon_shift_keytab: xmon_keytab)[k];
 		if (k != 0)
 			break;
 	}
 	xmon_wants_key = 0;
 	return k;
 }
 #endif /* CONFIG_BOOTX_TEXT */

 int
 xmon_read(void *handle, void *ptr, int nb)
 {
     char *p = ptr;
     int i;

 #ifdef CONFIG_BOOTX_TEXT
     if (use_screen) {
 	for (i = 0; i < nb; ++i)
 	    *p++ = xmon_get_adb_key();
 	return i;
     }
 #endif
     if (!scc_initialized)
 	xmon_init_scc();
     for (i = 0; i < nb; ++i) {
 	while ((*sccc & RXRDY) == 0)
 	    do_poll_adb();
 	buf_access();
 	*p++ = *sccd;
     }
     return i;
 }

 int
 xmon_read_poll(void)
 {
 	if ((*sccc & RXRDY) == 0) {
 		do_poll_adb();
 		return -1;
 	}
 	buf_access();
 	return *sccd;
 }

 static unsigned char scc_inittab[] = {
     13, 0,		/* set baud rate divisor */
     12, 1,
     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
 xmon_init_scc(void)
 {
 	if ( _machine == _MACH_chrp )
 	{
 		sccd[3] = 0x83; eieio();	/* LCR = 8N1 + DLAB */
 		sccd[0] = 12; eieio();		/* DLL = 9600 baud */
 		sccd[1] = 0; eieio();
 		sccd[2] = 0; eieio();		/* FCR = 0 */
 		sccd[3] = 3; eieio();		/* LCR = 8N1 */
 		sccd[1] = 0; eieio();		/* IER = 0 */
 	}
 	else if ( _machine == _MACH_Pmac )
 	{
 		int i, x;

 		if (channel_node != 0)
 			pmac_call_feature(
 				PMAC_FTR_SCC_ENABLE,
 				channel_node,
 				PMAC_SCC_ASYNC | PMAC_SCC_FLAG_XMON, 1);
 			printk(KERN_INFO "Serial port locked ON by debugger !\n");
 		if (via_modem && channel_node != 0) {
 			unsigned int t0;

 			pmac_call_feature(
 				PMAC_FTR_MODEM_ENABLE,
 				channel_node, 0, 1);
 			printk(KERN_INFO "Modem powered up by debugger !\n");
 			t0 = readtb();
 			while (readtb() - t0 < 3*TB_SPEED)
 				eieio();
 		}
 		/* use the B channel if requested */
 		if (xmon_use_sccb) {
 			sccc = (volatile unsigned char *)
 				((unsigned long)sccc & ~0x20);
 			sccd = sccc + 0x10;
 		}
 		for (i = 20000; i != 0; --i) {
 			x = *sccc; eieio();
 		}
 		*sccc = 9; eieio();		/* reset A or B side */
 		*sccc = ((unsigned long)sccc & 0x20)? 0x80: 0x40; eieio();
 		for (i = 0; i < sizeof(scc_inittab); ++i) {
 			*sccc = scc_inittab[i];
 			eieio();
 		}
 	}
 	scc_initialized = 1;
 	if (via_modem) {
 		for (;;) {
 			xmon_write(NULL, "ATE1V1\r", 7);
 			if (xmon_expect("OK", 5)) {
 				xmon_write(NULL, "ATA\r", 4);
 				if (xmon_expect("CONNECT", 40))
 					break;
 			}
 			xmon_write(NULL, "+++", 3);
 			xmon_expect("OK", 3);
 		}
 	}
 }

 #if 0
 extern int (*prom_entry)(void *);

 int
 xmon_exit(void)
 {
     struct prom_args {
 	char *service;
     } args;

     for (;;) {
 	args.service = "exit";
 	(*prom_entry)(&args);
     }
 }
 #endif

 void *xmon_stdin;
 void *xmon_stdout;
 void *xmon_stderr;

 void
 xmon_init(int arg)
 {
 	xmon_map_scc();
 }

 int
 xmon_putc(int c, void *f)
 {
     char ch = c;

     if (c == '\n')
 	xmon_putc('\r', f);
     return xmon_write(f, &ch, 1) == 1? c: -1;
 }

 int
 xmon_putchar(int c)
 {
     return xmon_putc(c, xmon_stdout);
 }

 int
 xmon_fputs(char *str, void *f)
 {
     int n = strlen(str);

     return xmon_write(f, str, n) == n? 0: -1;
 }

 int
 xmon_readchar(void)
 {
     char ch;

     for (;;) {
 	switch (xmon_read(xmon_stdin, &ch, 1)) {
 	case 1:
 	    return ch;
 	case -1:
 	    xmon_printf("read(stdin) returned -1\r\n", 0, 0);
 	    return -1;
 	}
     }
 }

 static char line[256];
 static char *lineptr;
 static int lineleft;

 int xmon_expect(const char *str, unsigned int timeout)
 {
 	int c;
 	unsigned int t0;

 	timeout *= TB_SPEED;
 	t0 = readtb();
 	do {
 		lineptr = line;
 		for (;;) {
 			c = xmon_read_poll();
 			if (c == -1) {
 				if (readtb() - t0 > timeout)
 					return 0;
 				continue;
 			}
 			if (c == '\n')
 				break;
 			if (c != '\r' && lineptr < &line[sizeof(line) - 1])
 				*lineptr++ = c;
 		}
 		*lineptr = 0;
 	} while (strstr(line, str) == NULL);
 	return 1;
 }

 int
 xmon_getchar(void)
 {
     int c;

     if (lineleft == 0) {
 	lineptr = line;
 	for (;;) {
 	    c = xmon_readchar();
 	    if (c == -1 || c == 4)
 		break;
 	    if (c == '\r' || c == '\n') {
 		*lineptr++ = '\n';
 		xmon_putchar('\n');
 		break;
 	    }
 	    switch (c) {
 	    case 0177:
 	    case '\b':
 		if (lineptr > line) {
 		    xmon_putchar('\b');
 		    xmon_putchar(' ');
 		    xmon_putchar('\b');
 		    --lineptr;
 		}
 		break;
 	    case 'U' & 0x1F:
 		while (lineptr > line) {
 		    xmon_putchar('\b');
 		    xmon_putchar(' ');
 		    xmon_putchar('\b');
 		    --lineptr;
 		}
 		break;
 	    default:
 		if (lineptr >= &line[sizeof(line) - 1])
 		    xmon_putchar('\a');
 		else {
 		    xmon_putchar(c);
 		    *lineptr++ = c;
 		}
 	    }
 	}
 	lineleft = lineptr - line;
 	lineptr = line;
     }
     if (lineleft == 0)
 	return -1;
     --lineleft;
     return *lineptr++;
 }

 char *
 xmon_fgets(char *str, int nb, void *f)
 {
     char *p;
     int c;

     for (p = str; p < str + nb - 1; ) {
 	c = xmon_getchar();
 	if (c == -1) {
 	    if (p == str)
 		return NULL;
 	    break;
 	}
 	*p++ = c;
 	if (c == '\n')
 	    break;
     }
     *p = 0;
     return str;
 }

 void
 xmon_enter(void)
 {
 #ifdef CONFIG_ADB_PMU
 	if (_machine == _MACH_Pmac) {
 		pmu_suspend();
 	}
 #endif
 }

 void
 xmon_leave(void)
 {
 #ifdef CONFIG_ADB_PMU
 	if (_machine == _MACH_Pmac) {
 		pmu_resume();
 	}
 #endif
 }
	/*
	* Copyright (C) 1996 Paul Mackerras.
	*/
	#include <linux/config.h>
	#include <linux/string.h>
	#include <asm/machdep.h>
	#include <asm/io.h>
	#include <asm/page.h>
	#include <linux/adb.h>
	#include <linux/pmu.h>
	#include <linux/cuda.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/sysrq.h>
	#include <linux/bitops.h>
	#include <asm/xmon.h>
	#include <asm/prom.h>
	#include <asm/bootx.h>
	#include <asm/machdep.h>
	#include <asm/errno.h>
	#include <asm/pmac_feature.h>
	#include <asm/processor.h>
	#include <asm/delay.h>
	#include <asm/btext.h>

	static volatile unsigned char sccc, sccd;
	unsigned int TXRDY, RXRDY, DLAB;
	static int xmon_expect(const char *str, unsigned int timeout);

	static int use_serial;
	static int use_screen;
	static int via_modem;
	static int xmon_use_sccb;
	static struct device_node *channel_node;

	#define TB_SPEED 25000000

	static inline unsigned int readtb(void)
	{
	unsigned int ret;

	asm volatile("mftb %0" : "=r" (ret) :);
	return ret;
	}

	void buf_access(void)
	{
	if (DLAB)
	sccd[3] &= ~DLAB; /* reset DLAB */
	}

	extern int adb_init(void);

	#ifdef CONFIG_PPC_CHRP
	/*
	* This looks in the "ranges" property for the primary PCI host bridge
	* to find the physical address of the start of PCI/ISA I/O space.
	* It is basically a cut-down version of pci_process_bridge_OF_ranges.
	*/
	static unsigned long chrp_find_phys_io_base(void)
	{
	struct device_node *node;
	unsigned int *ranges;
	unsigned long base = CHRP_ISA_IO_BASE;
	int rlen = 0;
	int np;

	node = find_devices("isa");
	if (node != NULL) {
	node = node->parent;
	if (node == NULL \|\| node->type == NULL
	\|\| strcmp(node->type, "pci") != 0)
	node = NULL;
	}
	if (node == NULL)
	node = find_devices("pci");
	if (node == NULL)
	return base;

	ranges = (unsigned int *) get_property(node, "ranges", &rlen);
	np = prom_n_addr_cells(node) + 5;
	while ((rlen -= np * sizeof(unsigned int)) >= 0) {
	if ((ranges[0] >> 24) == 1 && ranges[2] == 0) {
	/* I/O space starting at 0, grab the phys base */
	base = ranges[np - 3];
	break;
	}
	ranges += np;
	}
	return base;
	}
	#endif /* CONFIG_PPC_CHRP */

	#ifdef CONFIG_MAGIC_SYSRQ
	static void sysrq_handle_xmon(int key, struct pt_regs *regs,
	struct tty_struct *tty)
	{
	xmon(regs);
	}

	static struct sysrq_key_op sysrq_xmon_op =
	{
	.handler = sysrq_handle_xmon,
	.help_msg = "Xmon",
	.action_msg = "Entering xmon",
	};
	#endif

	void
	xmon_map_scc(void)
	{
	#ifdef CONFIG_PPC_MULTIPLATFORM
	volatile unsigned char *base;

	if (_machine == _MACH_Pmac) {
	struct device_node *np;
	unsigned long addr;
	#ifdef CONFIG_BOOTX_TEXT
	if (!use_screen && !use_serial
	&& !machine_is_compatible("iMac")) {
	/* see if there is a keyboard in the device tree
	with a parent of type "adb" */
	for (np = find_devices("keyboard"); np; np = np->next)
	if (np->parent && np->parent->type
	&& strcmp(np->parent->type, "adb") == 0)
	break;

	/* needs to be hacked if xmon_printk is to be used
	from within find_via_pmu() */
	#ifdef CONFIG_ADB_PMU
	if (np != NULL && boot_text_mapped && find_via_pmu())
	use_screen = 1;
	#endif
	#ifdef CONFIG_ADB_CUDA
	if (np != NULL && boot_text_mapped && find_via_cuda())
	use_screen = 1;
	#endif
	}
	if (!use_screen && (np = find_devices("escc")) != NULL) {
	/*
	* look for the device node for the serial port
	* we're using and see if it says it has a modem
	*/
	char *name = xmon_use_sccb? "ch-b": "ch-a";
	char *slots;
	int l;

	np = np->child;
	while (np != NULL && strcmp(np->name, name) != 0)
	np = np->sibling;
	if (np != NULL) {
	/* XXX should parse this properly */
	channel_node = np;
	slots = get_property(np, "slot-names", &l);
	if (slots != NULL && l >= 10
	&& strcmp(slots+4, "Modem") == 0)
	via_modem = 1;
	}
	}
	btext_drawstring("xmon uses ");
	if (use_screen)
	btext_drawstring("screen and keyboard\n");
	else {
	if (via_modem)
	btext_drawstring("modem on ");
	btext_drawstring(xmon_use_sccb? "printer": "modem");
	btext_drawstring(" port\n");
	}

	#endif /* CONFIG_BOOTX_TEXT */

	#ifdef CHRP_ESCC
	addr = 0xc1013020;
	#else
	addr = 0xf3013020;
	#endif
	TXRDY = 4;
	RXRDY = 1;

	np = find_devices("mac-io");
	if (np && np->n_addrs)
	addr = np->addrs[0].address + 0x13020;
	base = (volatile unsigned char *) ioremap(addr & PAGE_MASK, PAGE_SIZE);
	sccc = base + (addr & ~PAGE_MASK);
	sccd = sccc + 0x10;

	} else {
	base = (volatile unsigned char *) isa_io_base;
	if (_machine == _MACH_chrp)
	base = (volatile unsigned char *)
	ioremap(chrp_find_phys_io_base(), 0x1000);

	sccc = base + 0x3fd;
	sccd = base + 0x3f8;
	if (xmon_use_sccb) {
	sccc -= 0x100;
	sccd -= 0x100;
	}
	TXRDY = 0x20;
	RXRDY = 1;
	DLAB = 0x80;
	}
	#elif defined(CONFIG_GEMINI)
	/* should already be mapped by the kernel boot */
	sccc = (volatile unsigned char *) 0xffeffb0d;
	sccd = (volatile unsigned char *) 0xffeffb08;
	TXRDY = 0x20;
	RXRDY = 1;
	DLAB = 0x80;
	#elif defined(CONFIG_405GP)
	sccc = (volatile unsigned char *)0xef600305;
	sccd = (volatile unsigned char *)0xef600300;
	TXRDY = 0x20;
	RXRDY = 1;
	DLAB = 0x80;
	#endif /* platform */

	register_sysrq_key('x', &sysrq_xmon_op);
	}

	static int scc_initialized = 0;

	void xmon_init_scc(void);
	extern void cuda_poll(void);

	static inline void do_poll_adb(void)
	{
	#ifdef CONFIG_ADB_PMU
	if (sys_ctrler == SYS_CTRLER_PMU)
	pmu_poll_adb();
	#endif /* CONFIG_ADB_PMU */
	#ifdef CONFIG_ADB_CUDA
	if (sys_ctrler == SYS_CTRLER_CUDA)
	cuda_poll();
	#endif /* CONFIG_ADB_CUDA */
	}

	int
	xmon_write(void handle, void ptr, int nb)
	{
	char *p = ptr;
	int i, c, ct;

	#ifdef CONFIG_SMP
	static unsigned long xmon_write_lock;
	int lock_wait = 1000000;
	int locked;

	while ((locked = test_and_set_bit(0, &xmon_write_lock)) != 0)
	if (--lock_wait == 0)
	break;
	#endif

	#ifdef CONFIG_BOOTX_TEXT
	if (use_screen) {
	/* write it on the screen */
	for (i = 0; i < nb; ++i)
	btext_drawchar(*p++);
	goto out;
	}
	#endif
	if (!scc_initialized)
	xmon_init_scc();
	ct = 0;
	for (i = 0; i < nb; ++i) {
	while ((*sccc & TXRDY) == 0)
	do_poll_adb();
	c = p[i];
	if (c == '\n' && !ct) {
	c = '\r';
	ct = 1;
	--i;
	} else {
	ct = 0;
	}
	buf_access();
	*sccd = c;
	eieio();
	}

	out:
	#ifdef CONFIG_SMP
	if (!locked)
	clear_bit(0, &xmon_write_lock);
	#endif
	return nb;
	}

	int xmon_wants_key;
	int xmon_adb_keycode;

	#ifdef CONFIG_BOOTX_TEXT
	static int xmon_adb_shiftstate;

	static unsigned char xmon_keytab[128] =
	"asdfhgzxcv\000bqwer" /* 0x00 - 0x0f */
	"yt123465=97-80]o" /* 0x10 - 0x1f */
	"u[ip\rlj'k;\\,/nm." /* 0x20 - 0x2f */
	"\t `\177\0\033\0\0\0\0\0\0\0\0\0\0" /* 0x30 - 0x3f */
	"\0.\0\0+\0\0\0\0\0/\r\0-\0" / 0x40 - 0x4f */
	"\0\0000123456789\0\0\0"; /* 0x50 - 0x5f */

	static unsigned char xmon_shift_keytab[128] =
	"ASDFHGZXCV\000BQWER" /* 0x00 - 0x0f */
	"YT!@#$^%+(&_)}O" / 0x10 - 0x1f */
	"U{IP\rLJ\"K:\|<?NM>" /* 0x20 - 0x2f */
	"\t ~\177\0\033\0\0\0\0\0\0\0\0\0\0" /* 0x30 - 0x3f */
	"\0.\0\0+\0\0\0\0\0/\r\0-\0" / 0x40 - 0x4f */
	"\0\0000123456789\0\0\0"; /* 0x50 - 0x5f */

	static int
	xmon_get_adb_key(void)
	{
	int k, t, on;

	xmon_wants_key = 1;
	for (;;) {
	xmon_adb_keycode = -1;
	t = 0;
	on = 0;
	do {
	if (--t < 0) {
	on = 1 - on;
	btext_drawchar(on? 0xdb: 0x20);
	btext_drawchar('\b');
	t = 200000;
	}
	do_poll_adb();
	} while (xmon_adb_keycode == -1);
	k = xmon_adb_keycode;
	if (on)
	btext_drawstring(" \b");

	/* test for shift keys */
	if ((k & 0x7f) == 0x38 \|\| (k & 0x7f) == 0x7b) {
	xmon_adb_shiftstate = (k & 0x80) == 0;
	continue;
	}
	if (k >= 0x80)
	continue; /* ignore up transitions */
	k = (xmon_adb_shiftstate? xmon_shift_keytab: xmon_keytab)[k];
	if (k != 0)
	break;
	}
	xmon_wants_key = 0;
	return k;
	}
	#endif /* CONFIG_BOOTX_TEXT */

	int
	xmon_read(void handle, void ptr, int nb)
	{
	char *p = ptr;
	int i;

	#ifdef CONFIG_BOOTX_TEXT
	if (use_screen) {
	for (i = 0; i < nb; ++i)
	*p++ = xmon_get_adb_key();
	return i;
	}
	#endif
	if (!scc_initialized)
	xmon_init_scc();
	for (i = 0; i < nb; ++i) {
	while ((*sccc & RXRDY) == 0)
	do_poll_adb();
	buf_access();
	p++ = sccd;
	}
	return i;
	}

	int
	xmon_read_poll(void)
	{
	if ((*sccc & RXRDY) == 0) {
	do_poll_adb();
	return -1;
	}
	buf_access();
	return *sccd;
	}

	static unsigned char scc_inittab[] = {
	13, 0, /* set baud rate divisor */
	12, 1,
	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
	xmon_init_scc(void)
	{
	if ( _machine == _MACH_chrp )
	{
	sccd[3] = 0x83; eieio(); /* LCR = 8N1 + DLAB */
	sccd[0] = 12; eieio(); /* DLL = 9600 baud */
	sccd[1] = 0; eieio();
	sccd[2] = 0; eieio(); /* FCR = 0 */
	sccd[3] = 3; eieio(); /* LCR = 8N1 */
	sccd[1] = 0; eieio(); /* IER = 0 */
	}
	else if ( _machine == _MACH_Pmac )
	{
	int i, x;

	if (channel_node != 0)
	pmac_call_feature(
	PMAC_FTR_SCC_ENABLE,
	channel_node,
	PMAC_SCC_ASYNC \| PMAC_SCC_FLAG_XMON, 1);
	printk(KERN_INFO "Serial port locked ON by debugger !\n");
	if (via_modem && channel_node != 0) {
	unsigned int t0;

	pmac_call_feature(
	PMAC_FTR_MODEM_ENABLE,
	channel_node, 0, 1);
	printk(KERN_INFO "Modem powered up by debugger !\n");
	t0 = readtb();
	while (readtb() - t0 < 3*TB_SPEED)
	eieio();
	}
	/* use the B channel if requested */
	if (xmon_use_sccb) {
	sccc = (volatile unsigned char *)
	((unsigned long)sccc & ~0x20);
	sccd = sccc + 0x10;
	}
	for (i = 20000; i != 0; --i) {
	x = *sccc; eieio();
	}
	sccc = 9; eieio(); / reset A or B side */
	*sccc = ((unsigned long)sccc & 0x20)? 0x80: 0x40; eieio();
	for (i = 0; i < sizeof(scc_inittab); ++i) {
	*sccc = scc_inittab[i];
	eieio();
	}
	}
	scc_initialized = 1;
	if (via_modem) {
	for (;;) {
	xmon_write(NULL, "ATE1V1\r", 7);
	if (xmon_expect("OK", 5)) {
	xmon_write(NULL, "ATA\r", 4);
	if (xmon_expect("CONNECT", 40))
	break;
	}
	xmon_write(NULL, "+++", 3);
	xmon_expect("OK", 3);
	}
	}
	}

	#if 0
	extern int (prom_entry)(void );

	int
	xmon_exit(void)
	{
	struct prom_args {
	char *service;
	} args;

	for (;;) {
	args.service = "exit";
	(*prom_entry)(&args);
	}
	}
	#endif

	void *xmon_stdin;
	void *xmon_stdout;
	void *xmon_stderr;

	void
	xmon_init(int arg)
	{
	xmon_map_scc();
	}

	int
	xmon_putc(int c, void *f)
	{
	char ch = c;

	if (c == '\n')
	xmon_putc('\r', f);
	return xmon_write(f, &ch, 1) == 1? c: -1;
	}

	int
	xmon_putchar(int c)
	{
	return xmon_putc(c, xmon_stdout);
	}

	int
	xmon_fputs(char str, void f)
	{
	int n = strlen(str);

	return xmon_write(f, str, n) == n? 0: -1;
	}

	int
	xmon_readchar(void)
	{
	char ch;

	for (;;) {
	switch (xmon_read(xmon_stdin, &ch, 1)) {
	case 1:
	return ch;
	case -1:
	xmon_printf("read(stdin) returned -1\r\n", 0, 0);
	return -1;
	}
	}
	}

	static char line[256];
	static char *lineptr;
	static int lineleft;

	int xmon_expect(const char *str, unsigned int timeout)
	{
	int c;
	unsigned int t0;

	timeout *= TB_SPEED;
	t0 = readtb();
	do {
	lineptr = line;
	for (;;) {
	c = xmon_read_poll();
	if (c == -1) {
	if (readtb() - t0 > timeout)
	return 0;
	continue;
	}
	if (c == '\n')
	break;
	if (c != '\r' && lineptr < &line[sizeof(line) - 1])
	*lineptr++ = c;
	}
	*lineptr = 0;
	} while (strstr(line, str) == NULL);
	return 1;
	}

	int
	xmon_getchar(void)
	{
	int c;

	if (lineleft == 0) {
	lineptr = line;
	for (;;) {
	c = xmon_readchar();
	if (c == -1 \|\| c == 4)
	break;
	if (c == '\r' \|\| c == '\n') {
	*lineptr++ = '\n';
	xmon_putchar('\n');
	break;
	}
	switch (c) {
	case 0177:
	case '\b':
	if (lineptr > line) {
	xmon_putchar('\b');
	xmon_putchar(' ');
	xmon_putchar('\b');
	--lineptr;
	}
	break;
	case 'U' & 0x1F:
	while (lineptr > line) {
	xmon_putchar('\b');
	xmon_putchar(' ');
	xmon_putchar('\b');
	--lineptr;
	}
	break;
	default:
	if (lineptr >= &line[sizeof(line) - 1])
	xmon_putchar('\a');
	else {
	xmon_putchar(c);
	*lineptr++ = c;
	}
	}
	}
	lineleft = lineptr - line;
	lineptr = line;
	}
	if (lineleft == 0)
	return -1;
	--lineleft;
	return *lineptr++;
	}

	char *
	xmon_fgets(char str, int nb, void f)
	{
	char *p;
	int c;

	for (p = str; p < str + nb - 1; ) {
	c = xmon_getchar();
	if (c == -1) {
	if (p == str)
	return NULL;
	break;
	}
	*p++ = c;
	if (c == '\n')
	break;
	}
	*p = 0;
	return str;
	}

	void
	xmon_enter(void)
	{
	#ifdef CONFIG_ADB_PMU
	if (_machine == _MACH_Pmac) {
	pmu_suspend();
	}
	#endif
	}

	void
	xmon_leave(void)
	{
	#ifdef CONFIG_ADB_PMU
	if (_machine == _MACH_Pmac) {
	pmu_resume();
	}
	#endif
	}