Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 26 Feb 2003 15:29:06 -0500 (EST) | From | "Richard B. Johnson" <> | Subject | Re: [2.5.63 PATCH][TRIVIAL]Change rtc.c ioport extend from 10h to 8h |
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On 26 Feb 2003, Rusty Lynch wrote:
> On Wed, 2003-02-26 at 11:35, Richard B. Johnson wrote: > > On 26 Feb 2003, Rusty Lynch wrote: > > > > > The real time clock only needs 8 bytes, but rtc.c is reserving 10h bytes. > > [SNIPPED...] > > > > It only needs two bytes port 0x70 and port 0x71 in ix86. Since the Sparc > > gets addressed differently and can only read/write words, it needs 8 > > bytes. Please, if you are going to fix it, please fix it only once by > > setting a different length for the different machines! > > Cheers, > > Dick Johnson > > Actually, it's finer grain then x86, it's a chipset issue. As Randy > pointed out in the original thread ==> > > Some Intel chipset specs list RTC as using 0x70 - 0x77, probably with > > some aliasing in there, so it looks to me like an EXTENT of 8 would be > > safer and still allow you access to 0x79. > > > > I'm looking at 82801BA-ICH2, 82801-ICH3, and 82801AA-ICH0 specs. > > > > --
Can't see what an IDE chip-set has to do with it. The RTC can only be accessed as an offset-location and a data-location. You write an offset at one location and you read/write data at another location. On an ix86, the locations are adjacent byte-wide ports. On the Sparc they are adjacent dword-wide memory locations.
Cheers, Dick Johnson Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips). Why is the government concerned about the lunatic fringe? Think about it.
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