i386: fix machine rebooting

Commit 59f4e7d572980a521b7bdba74ab71b21f5995538 fixed machine rebooting
on Truxton's machine (when no keyboard was present).  But it broke it on
Lee's machine.

The patch reinstates the old (pre-59f4e7d572980a521b7bdba74ab71b21f5995538)
code and if that doesn't work out, try the new,
post-59f4e7d572980a521b7bdba74ab71b21f5995538 code instead.

Cc: Lee Garrett <lee-in-berlin@web.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/asm-i386/mach-default/mach_reboot.h b/include/asm-i386/mach-default/mach_reboot.h
index a955e57ad016a9ce203d90cce3b1f56ad7dbd2c0..e23fd9fbebb3a5b024a9c8c2e155ea02ae51c8a9 100644 (file)
--- a/include/asm-i386/mach-default/mach_reboot.h
+++ b/include/asm-i386/mach-default/mach_reboot.h
@@ -19,14 +19,37 @@ static inline void kb_wait(void)
 static inline void mach_reboot(void)
 {
        int i;
+
+       /* old method, works on most machines */
        for (i = 0; i < 10; i++) {
+               kb_wait();
+               udelay(50);
+               outb(0xfe, 0x64);       /* pulse reset low */
+               udelay(50);
+       }
+
+       /* New method: sets the "System flag" which, when set, indicates
+        * successful completion of the keyboard controller self-test (Basic
+        * Assurance Test, BAT).  This is needed for some machines with no
+        * keyboard plugged in.  This read-modify-write sequence sets only the
+        * system flag
+        */
+       for (i = 0; i < 10; i++) {
+               int cmd;
+
+               outb(0x20, 0x64);       /* read Controller Command Byte */
+               udelay(50);
+               kb_wait();
+               udelay(50);
+               cmd = inb(0x60);
+               udelay(50);
                kb_wait();
                udelay(50);
                outb(0x60, 0x64);       /* write Controller Command Byte */
                udelay(50);
                kb_wait();
                udelay(50);
-               outb(0x14, 0x60);       /* set "System flag" */
+               outb(cmd | 0x04, 0x60); /* set "System flag" */
                udelay(50);
                kb_wait();
                udelay(50);