diff -urpN -X /home/fletch/.diff.exclude 000-virgin/arch/i386/Kconfig 100-early_printk/arch/i386/Kconfig
--- 000-virgin/arch/i386/Kconfig Wed Jul 2 21:59:03 2003
+++ 100-early_printk/arch/i386/Kconfig Wed Jul 2 22:01:57 2003
@@ -1330,6 +1330,26 @@ config MAGIC_SYSRQ
keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
unless you really know what this hack does.
+config EARLY_PRINTK
+ bool "Early console support"
+ default n
+ depends on DEBUG_KERNEL
+ help
+ Write kernel log output directly into the VGA buffer or serial port.
+ This is useful for kernel debugging when your machine crashes very
+ early before the console code is initialized. For normal operation
+ it is not recommended because it looks ugly and doesn't cooperate
+ with klogd/syslogd or the X server.You should normally N here,
+ unless you want to debug such a crash.
+
+ Syntax: earlyprintk=vga
+ earlyprintk=serial[,ttySn[,baudrate]]
+ Append ,keep to not disable it when the real console takes over.
+ Only vga or serial at a time, not both.
+ Currently only ttyS0 and ttyS1 are supported.
+ Interaction with the standard serial driver is not very good.
+ The VGA output is eventually overwritten by the real console.
+
config DEBUG_SPINLOCK
bool "Spinlock debugging"
depends on DEBUG_KERNEL
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/arch/i386/kernel/smpboot.c 100-early_printk/arch/i386/kernel/smpboot.c
--- 000-virgin/arch/i386/kernel/smpboot.c Fri May 30 19:01:59 2003
+++ 100-early_printk/arch/i386/kernel/smpboot.c Wed Jul 2 22:01:57 2003
@@ -62,7 +62,7 @@ int smp_num_siblings = 1;
int phys_proc_id[NR_CPUS]; /* Package ID of each logical CPU */
/* Bitmask of currently online CPUs */
-unsigned long cpu_online_map;
+unsigned long cpu_online_map = 1;
static volatile unsigned long cpu_callin_map;
volatile unsigned long cpu_callout_map;
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/include/asm-i386/early_printk.h 100-early_printk/include/asm-i386/early_printk.h
--- 000-virgin/include/asm-i386/early_printk.h Wed Dec 31 16:00:00 1969
+++ 100-early_printk/include/asm-i386/early_printk.h Wed Jul 2 22:01:57 2003
@@ -0,0 +1,8 @@
+#ifndef __EARLY_PRINTK_H_I386_
+#define __EARLY_PRINTK_H_I386_
+
+#define VGABASE 0xB8000
+#define SERIAL_BASES { 0x3f8, 0x2f8 }
+#define SERIAL_BASES_LEN 2
+
+#endif
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/include/asm-x86_64/early_printk.h 100-early_printk/include/asm-x86_64/early_printk.h
--- 000-virgin/include/asm-x86_64/early_printk.h Wed Dec 31 16:00:00 1969
+++ 100-early_printk/include/asm-x86_64/early_printk.h Wed Jul 2 22:01:57 2003
@@ -0,0 +1,8 @@
+#ifndef __EARLY_PRINTK_H_X86_64_
+#define __EARLY_PRINTK_H_X86_64_
+
+#define VGABASE 0xffffffff800b8000UL
+#define SERIAL_BASES { 0x3f8, 0x2f8 }
+#define SERIAL_BASES_LEN 2
+
+#endif
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/include/linux/early_printk.h 100-early_printk/include/linux/early_printk.h
--- 000-virgin/include/linux/early_printk.h Wed Dec 31 16:00:00 1969
+++ 100-early_printk/include/linux/early_printk.h Wed Jul 2 22:01:57 2003
@@ -0,0 +1,47 @@
+#ifndef __EARLY_PRINTK_H_
+#define __EARLY_PRINTK_H_
+
+#ifdef CONFIG_EARLY_PRINTK
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <asm/io.h>
+#include <asm/early_printk.h>
+
+/* Simple VGA output */
+
+#define MAX_YPOS 25
+#define MAX_XPOS 80
+
+/* Simple serial port output */
+
+#define DEFAULT_BAUD 57600
+#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 */
+
+
+void early_printk(const char *fmt, ...);
+int __init setup_early_printk();
+
+#else
+
+#define early_printk(...) do {} while(0)
+#define setup_early_printk() do {} while(0)
+
+#endif
+
+#endif
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/init/main.c 100-early_printk/init/main.c
--- 000-virgin/init/main.c Tue Jun 17 20:58:54 2003
+++ 100-early_printk/init/main.c Wed Jul 2 22:01:57 2003
@@ -38,6 +38,7 @@
#include <linux/moduleparam.h>
#include <linux/writeback.h>
#include <linux/cpu.h>
+#include <linux/early_printk.h>
#include <asm/io.h>
#include <asm/bugs.h>
@@ -390,6 +391,8 @@ asmlinkage void __init start_kernel(void
*/
lock_kernel();
printk(linux_banner);
+ setup_early_printk();
+
setup_arch(&command_line);
setup_per_zone_pages_min();
setup_per_cpu_areas();
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/kernel/Makefile 100-early_printk/kernel/Makefile
--- 000-virgin/kernel/Makefile Fri May 30 19:02:24 2003
+++ 100-early_printk/kernel/Makefile Wed Jul 2 22:01:57 2003
@@ -19,6 +19,7 @@ obj-$(CONFIG_CPU_FREQ) += cpufreq.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
obj-$(CONFIG_SOFTWARE_SUSPEND) += suspend.o
obj-$(CONFIG_COMPAT) += compat.o
+obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
ifneq ($(CONFIG_IA64),y)
# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
diff -urpN -X /home/fletch/.diff.exclude 000-virgin/kernel/early_printk.c 100-early_printk/kernel/early_printk.c
--- 000-virgin/kernel/early_printk.c Wed Dec 31 16:00:00 1969
+++ 100-early_printk/kernel/early_printk.c Wed Jul 2 22:01:57 2003
@@ -0,0 +1,218 @@
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/early_printk.h>
+#include <asm/io.h>
+#include <asm/setup.h>
+#include <asm/pgtable.h>
+
+/* Simple VGA output */
+
+#define MAX_YPOS 25
+#define MAX_XPOS 80
+
+static int current_ypos = 1, current_xpos = 0;
+
+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 losely based on a similar package from Klaus P. Gerlicher */
+
+int early_serial_base; /* ttyS0 */
+
+static int early_serial_putc(unsigned char ch)
+{
+ unsigned timeout = 0xffff;
+ while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+ rep_nop();
+ 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) {
+ early_serial_putc(*s);
+ if (*s == '\n')
+ early_serial_putc('\r');
+ s++;
+ }
+}
+
+static __init void early_serial_init(char *opt)
+{
+ unsigned char c;
+ unsigned divisor, baud = DEFAULT_BAUD;
+ static int bases[] = SERIAL_BASES;
+ char *s, *e;
+
+ early_serial_base = bases[0];
+
+ if (*opt == ',')
+ ++opt;
+
+ s = strsep(&opt, ",");
+ if (s != NULL) {
+ unsigned port;
+ if (!strncmp(s,"0x",2))
+ early_serial_base = simple_strtoul(s, &e, 16);
+ else {
+ if (!strncmp(s,"ttyS",4))
+ s+=4;
+ port = simple_strtoul(s, &e, 10);
+ if (port > (SERIAL_BASES_LEN-1) || s == e)
+ port = 0;
+ early_serial_base = bases[port];
+ }
+ }
+
+ 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 */
+
+ s = strsep(&opt, ",");
+ if (s != NULL) {
+ 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 */
+struct console *early_console = &early_vga_console;
+static int early_console_initialized = 0;
+
+void early_printk(const char *fmt, ...)
+{
+ char buf[512];
+ int n;
+ va_list ap;
+ va_start(ap,fmt);
+ n = vsnprintf(buf,512,fmt,ap);
+ early_console->write(early_console,buf,n);
+ va_end(ap);
+}
+
+static int keep_early;
+
+int __init setup_early_printk(void)
+{
+ char *space, *s;
+ char buf[256];
+ char cmd[COMMAND_LINE_SIZE];
+ char *opt;
+
+ /* Get our own copy of the cmd line */
+ memcpy(cmd, COMMAND_LINE, COMMAND_LINE_SIZE);
+ cmd[COMMAND_LINE_SIZE-1] = '\0';
+ opt = cmd;
+
+ s = strstr(opt, "earlyprintk=");
+ if (s == NULL)
+ return -1;
+ opt = s+12;
+
+ if (early_console_initialized)
+ return -1;
+
+ strncpy(buf,opt,256);
+ buf[255] = 0;
+ space = strchr(buf, ' ');
+ if (space)
+ *space = 0;
+
+ 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)) {
+ early_console = &early_vga_console;
+ } else {
+ early_console = NULL;
+ return -1;
+ }
+ early_console_initialized = 1;
+ register_console(early_console);
+ printk("early printk console registered\n");
+ return 0;
+}
+
+void __init disable_early_printk(void)
+{
+ if (!early_console_initialized || !early_console)
+ return;
+ if (!keep_early) {
+ printk("disabling early console...\n");
+ unregister_console(early_console);
+ early_console_initialized = 0;
+ } else {
+ printk("keeping early console.\n");
+ }
+}
+
+/* syntax: earlyprintk=vga
+ earlyprintk=serial[,ttySn[,baudrate]]
+ Append ,keep to not disable it when the real console takes over.
+ Only vga or serial at a time, not both.
+ Currently only ttyS0 and ttyS1 are supported.
+ Interaction with the standard serial driver is not very good.
+ The VGA output is eventually overwritten by the real console. */
+__setup("earlyprintk=", setup_early_printk);