[mirror_ubuntu-artful-kernel.git] / arch / x86 / kernel / early_printk.c

#include <linux/console.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/screen_info.h>
#include <linux/usb/ch9.h>
#include <linux/pci_regs.h>
#include <linux/pci_ids.h>
#include <linux/errno.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/fcntl.h>
#include <asm/setup.h>
#include <xen/hvc-console.h>
#include <asm/pci-direct.h>
#include <asm/fixmap.h>
#include <asm/pgtable.h>
#include <linux/usb/ehci_def.h>

/* Simple VGA output */
#define VGABASE		(__ISA_IO_base + 0xb8000)

static int max_ypos = 25, max_xpos = 80;
static int current_ypos = 25, current_xpos;

static void early_vga_write(struct console *con, const char *str, unsigned n)
{
	char c;
	int  i, k, j;

	while ((c = *str++) != '\0' && n-- > 0) {
		if (current_ypos >= max_ypos) {
			/* scroll 1 line up */
			for (k = 1, j = 0; k < max_ypos; k++, j++) {
				for (i = 0; i < max_xpos; i++) {
					writew(readw(VGABASE+2*(max_xpos*k+i)),
					       VGABASE + 2*(max_xpos*j + i));
				}
			}
			for (i = 0; i < max_xpos; i++)
				writew(0x720, VGABASE + 2*(max_xpos*j + i));
			current_ypos = max_ypos-1;
		}
		if (c == '\n') {
			current_xpos = 0;
			current_ypos++;
		} else if (c != '\r')  {
			writew(((0x7 << 8) | (unsigned short) c),
			       VGABASE + 2*(max_xpos*current_ypos +
						current_xpos++));
			if (current_xpos >= max_xpos) {
				current_xpos = 0;
				current_ypos++;
			}
		}
	}
}

static struct console early_vga_console = {
	.name =		"earlyvga",
	.write =	early_vga_write,
	.flags =	CON_PRINTBUFFER,
	.index =	-1,
};

/* Serial functions loosely based on a similar package from Klaus P. Gerlicher */

static int early_serial_base = 0x3f8;  /* ttyS0 */

#define XMTRDY          0x20

#define DLAB		0x80

#define TXR             0       /*  Transmit register (WRITE) */
#define RXR             0       /*  Receive register  (READ)  */
#define IER             1       /*  Interrupt Enable          */
#define IIR             2       /*  Interrupt ID              */
#define FCR             2       /*  FIFO control              */
#define LCR             3       /*  Line control              */
#define MCR             4       /*  Modem control             */
#define LSR             5       /*  Line Status               */
#define MSR             6       /*  Modem Status              */
#define DLL             0       /*  Divisor Latch Low         */
#define DLH             1       /*  Divisor latch High        */

static int early_serial_putc(unsigned char ch)
{
	unsigned timeout = 0xffff;

	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
		cpu_relax();
	outb(ch, early_serial_base + TXR);
	return timeout ? 0 : -1;
}

static void early_serial_write(struct console *con, const char *s, unsigned n)
{
	while (*s && n-- > 0) {
		if (*s == '\n')
			early_serial_putc('\r');
		early_serial_putc(*s);
		s++;
	}
}

#define DEFAULT_BAUD 9600

static __init void early_serial_init(char *s)
{
	unsigned char c;
	unsigned divisor;
	unsigned baud = DEFAULT_BAUD;
	char *e;

	if (*s == ',')
		++s;

	if (*s) {
		unsigned port;
		if (!strncmp(s, "0x", 2)) {
			early_serial_base = simple_strtoul(s, &e, 16);
		} else {
			static const int __initconst bases[] = { 0x3f8, 0x2f8 };

			if (!strncmp(s, "ttyS", 4))
				s += 4;
			port = simple_strtoul(s, &e, 10);
			if (port > 1 || s == e)
				port = 0;
			early_serial_base = bases[port];
		}
		s += strcspn(s, ",");
		if (*s == ',')
			s++;
	}

	outb(0x3, early_serial_base + LCR);	/* 8n1 */
	outb(0, early_serial_base + IER);	/* no interrupt */
	outb(0, early_serial_base + FCR);	/* no fifo */
	outb(0x3, early_serial_base + MCR);	/* DTR + RTS */

	if (*s) {
		baud = simple_strtoul(s, &e, 0);
		if (baud == 0 || s == e)
			baud = DEFAULT_BAUD;
	}

	divisor = 115200 / baud;
	c = inb(early_serial_base + LCR);
	outb(c | DLAB, early_serial_base + LCR);
	outb(divisor & 0xff, early_serial_base + DLL);
	outb((divisor >> 8) & 0xff, early_serial_base + DLH);
	outb(c & ~DLAB, early_serial_base + LCR);
}

static struct console early_serial_console = {
	.name =		"earlyser",
	.write =	early_serial_write,
	.flags =	CON_PRINTBUFFER,
	.index =	-1,
};

/* Direct interface for emergencies */
static struct console *early_console = &early_vga_console;
static int __initdata early_console_initialized;

asmlinkage void early_printk(const char *fmt, ...)
{
	char buf[512];
	int n;
	va_list ap;

	va_start(ap, fmt);
	n = vscnprintf(buf, sizeof(buf), fmt, ap);
	early_console->write(early_console, buf, n);
	va_end(ap);
}


static int __init setup_early_printk(char *buf)
{
	int keep_early;

	if (!buf)
		return 0;

	if (early_console_initialized)
		return 0;
	early_console_initialized = 1;

	keep_early = (strstr(buf, "keep") != NULL);

	if (!strncmp(buf, "serial", 6)) {
		early_serial_init(buf + 6);
		early_console = &early_serial_console;
	} else if (!strncmp(buf, "ttyS", 4)) {
		early_serial_init(buf);
		early_console = &early_serial_console;
	} else if (!strncmp(buf, "vga", 3)
		&& boot_params.screen_info.orig_video_isVGA == 1) {
		max_xpos = boot_params.screen_info.orig_video_cols;
		max_ypos = boot_params.screen_info.orig_video_lines;
		current_ypos = boot_params.screen_info.orig_y;
		early_console = &early_vga_console;
#ifdef CONFIG_EARLY_PRINTK_DBGP
	} else if (!strncmp(buf, "dbgp", 4)) {
		if (early_dbgp_init(buf+4) < 0)
			return 0;
		early_console = &early_dbgp_console;
		/*
		 * usb subsys will reset ehci controller, so don't keep
		 * that early console
		 */
		keep_early = 0;
#endif
#ifdef CONFIG_HVC_XEN
	} else if (!strncmp(buf, "xen", 3)) {
		early_console = &xenboot_console;
#endif
	}

	if (keep_early)
		early_console->flags &= ~CON_BOOT;
	else
		early_console->flags |= CON_BOOT;
	register_console(early_console);
	return 0;
}

early_param("earlyprintk", setup_early_printk);
Commit	Line	Data
250c2277 TG	1	#include <linux/console.h>
	2	#include <linux/kernel.h>
	3	#include <linux/init.h>
	4	#include <linux/string.h>
	5	#include <linux/screen_info.h>
5c05917e YL	6	#include <linux/usb/ch9.h>
	7	#include <linux/pci_regs.h>
	8	#include <linux/pci_ids.h>
	9	#include <linux/errno.h>
250c2277 TG	10	#include <asm/io.h>
	11	#include <asm/processor.h>
	12	#include <asm/fcntl.h>
30c82645	13	#include <asm/setup.h>
250c2277	14	#include <xen/hvc-console.h>
5c05917e	15	#include <asm/pci-direct.h>
5c05917e	16	#include <asm/fixmap.h>
726c0d95	17	#include <asm/pgtable.h>
5c05917e	18	#include <linux/usb/ehci_def.h>
1da177e4	19
250c2277	20	/* Simple VGA output */
250c2277 TG	21	#define VGABASE (__ISA_IO_base + 0xb8000)
	22
	23	static int max_ypos = 25, max_xpos = 80;
c9cf39ae	24	static int current_ypos = 25, current_xpos;
250c2277 TG	25
	26	static void early_vga_write(struct console con, const char str, unsigned n)
	27	{
	28	char c;
	29	int i, k, j;
	30
	31	while ((c = *str++) != '\0' && n-- > 0) {
	32	if (current_ypos >= max_ypos) {
	33	/* scroll 1 line up */
	34	for (k = 1, j = 0; k < max_ypos; k++, j++) {
	35	for (i = 0; i < max_xpos; i++) {
	36	writew(readw(VGABASE+2(max_xposk+i)),
	37	VGABASE + 2(max_xposj + i));
	38	}
	39	}
	40	for (i = 0; i < max_xpos; i++)
	41	writew(0x720, VGABASE + 2(max_xposj + i));
	42	current_ypos = max_ypos-1;
	43	}
	44	if (c == '\n') {
	45	current_xpos = 0;
	46	current_ypos++;
	47	} else if (c != '\r') {
	48	writew(((0x7 << 8) \| (unsigned short) c),
	49	VGABASE + 2(max_xposcurrent_ypos +
	50	current_xpos++));
	51	if (current_xpos >= max_xpos) {
	52	current_xpos = 0;
	53	current_ypos++;
	54	}
	55	}
	56	}
	57	}
	58
	59	static struct console early_vga_console = {
	60	.name = "earlyvga",
	61	.write = early_vga_write,
	62	.flags = CON_PRINTBUFFER,
	63	.index = -1,
	64	};
	65
	66	/* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
	67
	68	static int early_serial_base = 0x3f8; /* ttyS0 */
	69
	70	#define XMTRDY 0x20
	71
	72	#define DLAB 0x80
	73
	74	#define TXR 0 /* Transmit register (WRITE) */
	75	#define RXR 0 /* Receive register (READ) */
	76	#define IER 1 /* Interrupt Enable */
	77	#define IIR 2 /* Interrupt ID */
	78	#define FCR 2 /* FIFO control */
	79	#define LCR 3 /* Line control */
	80	#define MCR 4 /* Modem control */
	81	#define LSR 5 /* Line Status */
	82	#define MSR 6 /* Modem Status */
	83	#define DLL 0 /* Divisor Latch Low */
	84	#define DLH 1 /* Divisor latch High */
	85
	86	static int early_serial_putc(unsigned char ch)
	87	{
	88	unsigned timeout = 0xffff;
5c05917e	89
250c2277 TG	90	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
	91	cpu_relax();
	92	outb(ch, early_serial_base + TXR);
	93	return timeout ? 0 : -1;
	94	}
	95
	96	static void early_serial_write(struct console con, const char s, unsigned n)
	97	{
	98	while (*s && n-- > 0) {
	99	if (*s == '\n')
	100	early_serial_putc('\r');
	101	early_serial_putc(*s);
	102	s++;
	103	}
	104	}
	105
	106	#define DEFAULT_BAUD 9600
	107
	108	static __init void early_serial_init(char *s)
	109	{
	110	unsigned char c;
	111	unsigned divisor;
	112	unsigned baud = DEFAULT_BAUD;
	113	char *e;
	114
	115	if (*s == ',')
	116	++s;
	117
	118	if (*s) {
	119	unsigned port;
e941f27a	120	if (!strncmp(s, "0x", 2)) {
250c2277 TG	121	early_serial_base = simple_strtoul(s, &e, 16);
250c2277 TG	122	} else {
30cec979	123	static const int __initconst bases[] = { 0x3f8, 0x2f8 };
250c2277	124
e941f27a	125	if (!strncmp(s, "ttyS", 4))
250c2277 TG	126	s += 4;
	127	port = simple_strtoul(s, &e, 10);
	128	if (port > 1 \|\| s == e)
	129	port = 0;
	130	early_serial_base = bases[port];
	131	}
	132	s += strcspn(s, ",");
	133	if (*s == ',')
	134	s++;
	135	}
	136
	137	outb(0x3, early_serial_base + LCR); /* 8n1 */
	138	outb(0, early_serial_base + IER); /* no interrupt */
	139	outb(0, early_serial_base + FCR); /* no fifo */
	140	outb(0x3, early_serial_base + MCR); /* DTR + RTS */
	141
	142	if (*s) {
	143	baud = simple_strtoul(s, &e, 0);
	144	if (baud == 0 \|\| s == e)
	145	baud = DEFAULT_BAUD;
	146	}
	147
	148	divisor = 115200 / baud;
	149	c = inb(early_serial_base + LCR);
	150	outb(c \| DLAB, early_serial_base + LCR);
	151	outb(divisor & 0xff, early_serial_base + DLL);
	152	outb((divisor >> 8) & 0xff, early_serial_base + DLH);
	153	outb(c & ~DLAB, early_serial_base + LCR);
	154	}
	155
	156	static struct console early_serial_console = {
	157	.name = "earlyser",
	158	.write = early_serial_write,
	159	.flags = CON_PRINTBUFFER,
	160	.index = -1,
	161	};
	162
250c2277	163	/* Direct interface for emergencies */
bb0e1290	164	static struct console *early_console = &early_vga_console;
30cec979	165	static int __initdata early_console_initialized;
250c2277	166
e17ba73b	167	asmlinkage void early_printk(const char *fmt, ...)
250c2277 TG	168	{
	169	char buf[512];
	170	int n;
	171	va_list ap;
	172
e941f27a	173	va_start(ap, fmt);
c64d8996	174	n = vscnprintf(buf, sizeof(buf), fmt, ap);
e941f27a	175	early_console->write(early_console, buf, n);
250c2277 TG	176	va_end(ap);
	177	}
	178
250c2277 TG	179
	180	static int __init setup_early_printk(char *buf)
	181	{
5c05917e YL	182	int keep_early;
5c05917e YL	183
250c2277 TG	184	if (!buf)
	185	return 0;
	186
	187	if (early_console_initialized)
	188	return 0;
	189	early_console_initialized = 1;
	190
5c05917e	191	keep_early = (strstr(buf, "keep") != NULL);
250c2277 TG	192
	193	if (!strncmp(buf, "serial", 6)) {
	194	early_serial_init(buf + 6);
	195	early_console = &early_serial_console;
	196	} else if (!strncmp(buf, "ttyS", 4)) {
	197	early_serial_init(buf);
	198	early_console = &early_serial_console;
	199	} else if (!strncmp(buf, "vga", 3)
e941f27a	200	&& boot_params.screen_info.orig_video_isVGA == 1) {
30c82645 PA	201	max_xpos = boot_params.screen_info.orig_video_cols;
	202	max_ypos = boot_params.screen_info.orig_video_lines;
	203	current_ypos = boot_params.screen_info.orig_y;
250c2277	204	early_console = &early_vga_console;
5c05917e YL	205	#ifdef CONFIG_EARLY_PRINTK_DBGP
	206	} else if (!strncmp(buf, "dbgp", 4)) {
	207	if (early_dbgp_init(buf+4) < 0)
	208	return 0;
	209	early_console = &early_dbgp_console;
	210	/*
	211	* usb subsys will reset ehci controller, so don't keep
	212	* that early console
	213	*/
	214	keep_early = 0;
	215	#endif
250c2277 TG	216	#ifdef CONFIG_HVC_XEN
	217	} else if (!strncmp(buf, "xen", 3)) {
	218	early_console = &xenboot_console;
	219	#endif
	220	}
	221
	222	if (keep_early)
	223	early_console->flags &= ~CON_BOOT;
	224	else
	225	early_console->flags \|= CON_BOOT;
	226	register_console(early_console);
	227	return 0;
	228	}
5c05917e	229
250c2277	230	early_param("earlyprintk", setup_early_printk);