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* x86: io_delay.c cleanupJaswinder Singh Rajput2009-03-211-14/+13
| | | | | | | | Impact: cleanup - fix header file issues Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
* x86: add io delay quirk for Presario F700Chuck Ebbert2008-09-031-0/+8
| | | | | | | | | | | | | | | | | | | Manually adding "io_delay=0xed" fixes system lockups in ioapic mode on this machine. System Information Manufacturer: Hewlett-Packard Product Name: Presario F700 (KA695EA#ABF) Base Board Information Manufacturer: Quanta Product Name: 30D3 Reference: https://bugzilla.redhat.com/show_bug.cgi?id=459546 Signed-off-by: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86: io delay - add checking for NULL early paramCyrill Gorcunov2008-07-091-0/+3
| | | | | | | Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Cc: akpm@linux-foundation.org Cc: andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: add dmi quirk for io_delayIngo Molnar2008-03-261-0/+8
| | | | | | | | | reported by mereandor@gmail.com, in: http://bugzilla.kernel.org/show_bug.cgi?id=6307 Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: unexport io_delay_typeAdrian Bunk2008-02-191-1/+0
| | | | | | | Signed-off-by: Adrian Bunk <bunk@kernel.org> Cc: hpa@zytor.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: add DMI quirk for io-delay hangs on Compaq Presario V6000 laptopsIngo Molnar2008-01-301-0/+16
| | | | | | | | add the DMI strings provided by Islam Amer <pharon@gmail.com>, for the Compaq Presario V6000 (Quanta/30B7). Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: various changes and cleanups to in_p/out_p delay detailsIngo Molnar2008-01-301-57/+49
| | | | | | | | | | | | | | | 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>
* x86: provide a DMI based port 0x80 I/O delay override.Rene Herman2008-01-301-0/+106
x86: provide a DMI based port 0x80 I/O delay override. Certain (HP) laptops experience trouble from our port 0x80 I/O delay writes. This patch provides for a DMI based switch to the "alternate diagnostic port" 0xed (as used by some BIOSes as well) for these. David P. Reed confirmed that port 0xed works for him and provides a proper delay. The symptoms of _not_ working are a hanging machine, with "hwclock" use being a direct trigger. Earlier versions of this attempted to simply use udelay(2), with the 2 being a value tested to be a nicely conservative upper-bound with help from many on the linux-kernel mailinglist but that approach has two problems. First, pre-loops_per_jiffy calibration (which is post PIT init while some implementations of the PIT are actually one of the historically problematic devices that need the delay) udelay() isn't particularly well-defined. We could initialise loops_per_jiffy conservatively (and based on CPU family so as to not unduly delay old machines) which would sort of work, but... Second, delaying isn't the only effect that a write to port 0x80 has. It's also a PCI posting barrier which some devices may be explicitly or implicitly relying on. Alan Cox did a survey and found evidence that additionally some drivers may be racy on SMP without the bus locking outb. Switching to an inb() makes the timing too unpredictable and as such, this DMI based switch should be the safest approach for now. Any more invasive changes should get more rigid testing first. It's moreover only very few machines with the problem and a DMI based hack seems to fit that situation. This also introduces a command-line parameter "io_delay" to override the DMI based choice again: io_delay=<standard|alternate> where "standard" means using the standard port 0x80 and "alternate" port 0xed. This retains the udelay method as a config (CONFIG_UDELAY_IO_DELAY) and command-line ("io_delay=udelay") choice for testing purposes as well. This does not change the io_delay() in the boot code which is using the same port 0x80 I/O delay but those do not appear to be a problem as David P. Reed reported the problem was already gone after using the udelay version. He moreover reported that booting with "acpi=off" also fixed things and seeing as how ACPI isn't touched until after this DMI based I/O port switch I believe it's safe to leave the ones in the boot code be. The DMI strings from David's HP Pavilion dv9000z are in there already and we need to get/verify the DMI info from other machines with the problem, notably the HP Pavilion dv6000z. This patch is partly based on earlier patches from Pavel Machek and David P. Reed. Signed-off-by: Rene Herman <rene.herman@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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