Re: [linux-kernel] Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay override.

!MAILaRCHIVE_VOTE_RePLACE
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
To: David P. Reed <dpreed@...>
Cc: Bodo Eggert <7eggert@...>, Rene Herman <rene.herman@...>, H. Peter Anvin <hpa@...>, Christer Weinigel <christer@...>, Ingo Molnar <mingo@...>, Paul Rolland <rol@...>, Pavel Machek <pavel@...>, Thomas Gleixner <tglx@...>, <linux-kernel@...>, Ingo Molnar <mingo@...>, <rol@...>
Date: Tuesday, January 8, 2008 - 10:37 am

> The last time I heard of a 12 MHz bus in a PC system was in the days of 

It wasn't about clone makers speeding up their busses. The ISA bus
originally ran at the CPU clock - 4.77/8/6/10 .. etc. Quite a few board
makers assumed 8MHz and while faster isn't a big problem at 8bit trying
to do the 8/16 bit decode with logic chips at 8MHz is quite tight and
above that generally broke. 8bit tends to work fine because you've got a
lot more timing headroom.


It is about supporting this properly. Properly for ISA devices means
using I/O delays. Properly for chipset devices is probably using udelay.


Linux runs on x86, it isn't limited to PC type architectures at all. We
don't need a BIOS, we don't need legacy compatible I/O devices.


No point. We've got the 64bit kernel for that. That is a much saner
boundary to throw out all the nutty stuff.

Alan
--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay ove..., Christer Weinigel, (Mon Jan 7, 11:15 pm)
Re: [linux-kernel] Re: [PATCH] x86: provide a DMI based port..., Alan Cox, (Tue Jan 8, 10:37 am)