#include <linux/console.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/screen_info.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/fcntl.h>
#include <asm/setup.h>
#include <xen/hvc-console.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 int 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,
};
/* Console interface to a host file on AMD's SimNow! */
static int simnow_fd;
enum {
MAGIC1 = 0xBACCD00A,
MAGIC2 = 0xCA110000,
XOPEN = 5,
XWRITE = 4,
};
static noinline long simnow(long cmd, long a, long b, long c)
{
long ret;
asm volatile("cpuid" :
"=a" (ret) :
"b" (a), "c" (b), "d" (c), "0" (MAGIC1), "D" (cmd + MAGIC2));
return ret;
}
static void __init simnow_init(char *str)
{
char *fn = "klog";
if (*str == '=')
fn = ++str;
/* error ignored */
simnow_fd = simnow(XOPEN, (unsigned long)fn, O_WRONLY|O_APPEND|O_CREAT, 0644);
}
static void simnow_write(struct console *con, const char *s, unsigned n)
{
simnow(XWRITE, simnow_fd, (unsigned long)s, n);
}
static struct console simnow_console = {
.name = "simnow",
.write = simnow_write,
.flags = CON_PRINTBUFFER,
.index = -1,
};
/* Direct interface for emergencies */
static struct console *early_console = &early_vga_console;
static int 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, 512, fmt, ap);
early_console->write(early_console, buf, n);
va_end(ap);
}
static int __initdata keep_early;
static int __init setup_early_printk(char *buf)
{
if (!buf)
return 0;
if (early_console_initialized)
return 0;
early_console_initialized = 1;
if (strstr(buf, "keep"))
keep_early = 1;
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;
} else if (!strncmp(buf, "simnow", 6)) {
simnow_init(buf + 6);
early_console = &simnow_console;
keep_early = 1;
#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);
