[U-Boot,12/12] x86: Don't spam POST80 codes with slow IO functions

Submitted by Simon Glass on Oct. 20, 2012, 10:33 p.m.

Details

Message ID 1350772396-28946-13-git-send-email-sjg@chromium.org
State Accepted, archived
Delegated to: Simon Glass
Headers show

Commit Message

Simon Glass Oct. 20, 2012, 10:33 p.m.
From: Stefan Reinauer <reinauer@chromium.org>

This patch prevents u-boot from "spamming" random progress codes on
a port 80 "post card".
The previous version of this patch just removed the delays in the "slow"
IO functions, as they do not need to be slow, however, this patch is
less intrusive.

It uses another unused port that is often used by BIOSes (and the Linux
Kernel) for small delay timing purposes.

Signed-off-by: Stefan Reinauer <reinauer@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
---
 arch/x86/include/asm/io.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

Patch hide | download patch | download mbox

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 2214958..84a638d 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -137,7 +137,7 @@  out:
 #ifdef SLOW_IO_BY_JUMPING
 #define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
 #else
-#define __SLOW_DOWN_IO "\noutb %%al,$0x80"
+#define __SLOW_DOWN_IO "\noutb %%al,$0xed"
 #endif
 
 #ifdef REALLY_SLOW_IO