Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 220 insertions, 0 deletions

diff --git a/arch/x86_64/kernel/early_printk.c b/arch/x86_64/kernel/early_printk.c
new file mode 100644
index 000000000000..750bcd0655dc
--- /dev/null
+++ b/arch/x86_64/kernel/early_printk.c
@@ -0,0 +1,220 @@
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+
+/* Simple VGA output */
+
+#ifdef __i386__
+#define VGABASE         (__ISA_IO_base + 0xb8000)
+#else
+#define VGABASE         ((void __iomem *)0xffffffff800b8000UL)
+#endif
+
+#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 loosely based on a similar package from Klaus P. Gerlicher */ 
+
+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) { 
+                early_serial_putc(*s); 
+                if (*s == '\n') 
+                        early_serial_putc('\r'); 
+                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,
+};
+
+/* 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 = vscnprintf(buf,512,fmt,ap);
+        early_console->write(early_console,buf,n);
+        va_end(ap); 
+} 
+
+static int keep_early; 
+
+int __init setup_early_printk(char *opt) 
+{  
+        char *space;
+        char buf[256]; 
+
+        if (early_console_initialized)
+                return -1;
+
+        opt = strchr(opt, '=') + 1;
+
+        strlcpy(buf,opt,sizeof(buf)); 
+        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; 
+        }
+        early_console_initialized = 1;
+        register_console(early_console);       
+        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");
+        }
+} 
+
+__setup("earlyprintk=", setup_early_printk);