1 files changed, 81 insertions, 0 deletions

diff --git a/arch/x86/kernel/acpi/realmode/wakemain.c b/arch/x86/kernel/acpi/realmode/wakemain.c
new file mode 100644
index 000000000000..883962d9eef2
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/wakemain.c
@@ -0,0 +1,81 @@
+#include "wakeup.h"
+#include "boot.h"
+
+static void udelay(int loops)
+{
+        while (loops--)
+                io_delay();     /* Approximately 1 us */
+}
+
+static void beep(unsigned int hz)
+{
+        u8 enable;
+
+        if (!hz) {
+                enable = 0x00;          /* Turn off speaker */
+        } else {
+                u16 div = 1193181/hz;
+
+                outb(0xb6, 0x43);       /* Ctr 2, squarewave, load, binary */
+                io_delay();
+                outb(div, 0x42);        /* LSB of counter */
+                io_delay();
+                outb(div >> 8, 0x42);   /* MSB of counter */
+                io_delay();
+
+                enable = 0x03;          /* Turn on speaker */
+        }
+        inb(0x61);              /* Dummy read of System Control Port B */
+        io_delay();
+        outb(enable, 0x61);     /* Enable timer 2 output to speaker */
+        io_delay();
+}
+
+#define DOT_HZ          880
+#define DASH_HZ         587
+#define US_PER_DOT      125000
+
+/* Okay, this is totally silly, but it's kind of fun. */
+static void send_morse(const char *pattern)
+{
+        char s;
+
+        while ((s = *pattern++)) {
+                switch (s) {
+                case '.':
+                        beep(DOT_HZ);
+                        udelay(US_PER_DOT);
+                        beep(0);
+                        udelay(US_PER_DOT);
+                        break;
+                case '-':
+                        beep(DASH_HZ);
+                        udelay(US_PER_DOT * 3);
+                        beep(0);
+                        udelay(US_PER_DOT);
+                        break;
+                default:        /* Assume it's a space */
+                        udelay(US_PER_DOT * 3);
+                        break;
+                }
+        }
+}
+
+void main(void)
+{
+        /* Kill machine if structures are wrong */
+        if (wakeup_header.real_magic != 0x12345678)
+                while (1);
+
+        if (wakeup_header.realmode_flags & 4)
+                send_morse("...-");
+
+        if (wakeup_header.realmode_flags & 1)
+                asm volatile("lcallw   $0xc000,$3");
+
+        if (wakeup_header.realmode_flags & 2) {
+                /* Need to call BIOS */
+                probe_cards(0);
+                set_mode(wakeup_header.video_mode);
+        }
+}