x86: various changes and cleanups to in_p/out_p delay details
various changes to the in_p/out_p delay details:
- add the io_delay=none method
- make each method selectable from the kernel config
- simplify the delay code a bit by getting rid of an indirect function call
- add the /proc/sys/kernel/io_delay_type sysctl
- change 'io_delay=standard|alternate' to io_delay=0x80 and io_delay=0xed
- make the io delay config not depend on CONFIG_DEBUG_KERNEL
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: "David P. Reed" <dpreed@reed.com>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 9e60560..b427b7c 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -795,12 +795,14 @@
then look in the higher range.
io_delay= [X86-32,X86-64] I/O delay method
- standard
- Standard port 0x80 delay
- alternate
- Alternate port 0xed delay
+ 0x80
+ Standard port 0x80 based delay
+ 0xed
+ Alternate port 0xed based delay (needed on some systems)
udelay
- Simple two microsecond delay
+ Simple two microseconds delay
+ none
+ No delay
io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in