From 6e7c402590b75b6b45138792445ee0f0315a8473 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 30 Jan 2008 13:30:05 +0100 Subject: 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 Signed-off-by: Thomas Gleixner Tested-by: "David P. Reed" --- arch/x86/Kconfig.debug | 79 +++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 72 insertions(+), 7 deletions(-) (limited to 'arch/x86/Kconfig.debug') diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 40aba670fb37..77eda46f97b8 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -112,13 +112,78 @@ config IOMMU_LEAK Add a simple leak tracer to the IOMMU code. This is useful when you are debugging a buggy device driver that leaks IOMMU mappings. -config UDELAY_IO_DELAY - bool "Delay I/O through udelay instead of outb" - depends on DEBUG_KERNEL +# +# IO delay types: +# + +config IO_DELAY_TYPE_0X80 + int + default "0" + +config IO_DELAY_TYPE_0XED + int + default "1" + +config IO_DELAY_TYPE_UDELAY + int + default "2" + +config IO_DELAY_TYPE_NONE + int + default "3" + +choice + prompt "IO delay type" + default IO_DELAY_0X80 + +config IO_DELAY_0X80 + bool "port 0x80 based port-IO delay [recommended]" + help + This is the traditional Linux IO delay used for in/out_p. + It is the most tested hence safest selection here. + +config IO_DELAY_0XED + bool "port 0xed based port-IO delay" + help + Use port 0xed as the IO delay. This frees up port 0x80 which is + often used as a hardware-debug port. + +config IO_DELAY_UDELAY + bool "udelay based port-IO delay" + help + Use udelay(2) as the IO delay method. This provides the delay + while not having any side-effect on the IO port space. + +config IO_DELAY_NONE + bool "no port-IO delay" help - Make inb_p/outb_p use udelay() based delays by default. Please note - that udelay() does not have the same bus-level side-effects that - the normal outb based delay does meaning this could cause drivers - to change behaviour and/or bugs to surface. + No port-IO delay. Will break on old boxes that require port-IO + delay for certain operations. Should work on most new machines. + +endchoice + +if IO_DELAY_0X80 +config DEFAULT_IO_DELAY_TYPE + int + default IO_DELAY_TYPE_0X80 +endif + +if IO_DELAY_0XED +config DEFAULT_IO_DELAY_TYPE + int + default IO_DELAY_TYPE_0XED +endif + +if IO_DELAY_UDELAY +config DEFAULT_IO_DELAY_TYPE + int + default IO_DELAY_TYPE_UDELAY +endif + +if IO_DELAY_NONE +config DEFAULT_IO_DELAY_TYPE + int + default IO_DELAY_TYPE_NONE +endif endmenu -- cgit v1.2.3