Nforce2 66MHz IDE without idebus=xx and "Athlon-xp powersaving system lock"

If all Nvidia Nforce2 based systems have 2 pci buses (First is 66mhz for onboard devices and second is 33mhz for pci expansion slots) and IDE controller work in 66mhz, will be change kernel to start IDE controller in 66mhz mode automatic?

Athlon-xp powersaving lock-up: mm series disable 'Halt Disconnect and Stop Grant Disconnect' on boot!

Without mm patchs I disable it with "athcool" tool, kernel developers maybe include automatic disable 'Halt Disconnect and Stop Grant Disconnect' on Linus tree?

from athcool menssages
=====================================
!!!WARNING!!!
Depending on your motherboard and/or hardware components, enabling Athlon powersaving mode sometimes causes that
* noisy or distorted sound playback
* a slowdown in harddisk performance
* system locks or instability
=======================================

dmesg
================================================
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
NFORCE2: IDE controller at PCI slot 0000:00:09.0
NFORCE2: chipset revision 162
NFORCE2: not 100% native mode: will probe irqs later
NFORCE2: BIOS didn't set cable bits correctly. Enabling workaround.
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
NFORCE2: 0000:00:09.0 (rev a2) UDMA133 controller

    ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hda:DMA, hdb:DMA
    ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdc:DMA, hdd:DMA

hda: Maxtor 6E040L0, ATA DISK drive
hdb: HL-DT-ST GCE-8525B, ATAPI CD/DVD-ROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
hda: max request size: 128KiB
hda: 80293248 sectors (41110 MB) w/2048KiB Cache, CHS=65535/16/63, UDMA(133)
==================================================

lspci -v
===================================================
00:09.0 IDE interface: nVidia Corporation nForce2 IDE (rev a2) (prog-if 8a [Master SecP PriP])
Subsystem: Micro-Star International Co., Ltd.: Unknown device 5700
Flags: bus master, 66Mhz, fast devsel, latency 0
I/O ports at f000 [size=16]
Capabilities: [44] Power Management version 2
====================================================

Thanks

Those patches are no longer included in -mm kernels.

As you can probably guess, enabling the C1 disconnect bit should not cause system instability. Simply disabling the C1 disconnect bit is not a very good way of solving the problem. Thats why those earlier "fixes" are no longer included in the -mm tree.

Ross Dickson has been doing some good research here - it does seem to be a hardware/firmware related bug, the CPU acting too soon after coming out of a disconnect (not too sure on the details here, its a little over my head). The lockup bug (for me) only shows itself when I enable APIC/IO-APIC in my kernel configuration, the older XTPIC interrupt paths are slower and tend not to trigger this bug as much.

With Ross's patches, you can boot with an apic_tack argument. When this argument is "1" it will introduce a delay to get rid of the problem. When you use "2" it will only enable the delay when a lockup is predicted. For me, apic_tack=2 has solved the problem, with C1 disconnect on, and APIC/IO-APIC enabled.

There's one side effect that a few people have reported: The clock appears to skew, gains about 15 mins over the period of 4-5 days. I have experienced this too.

See this thread for more info:
http://marc.theaimsgroup.com/?l=linux-kernel&m=107199838022614&w=2

Daniel.

The IDE controller base clock is 33MHz on the NForce2, although the ide controller itself is connected to the HyperTransport link, running at 200 MHz or so.

This 66 MHz and the above 33 MHz numbers are completely unrelated. Just forget about setting idebus to anything else than it is default. Bigger numbers mean _slower_ performance anyway.

Vojtech Pavlik
SuSE Labs, SuSE CR