On Fri, Nov 17, 2000 at 03:27:28PM -0500, Richard B. Johnson wrote: > Then, you read the port as a WORD (16 bits). If nothing responds, > you get the value of 0xffff. If somebody is responding, you will > read something if it's enabled for writes by devices (reads by the CPU). What guarantees you that: 1- No device will respond 0xffff for an address it decodes 2- No device will crap up on you simply because you've read one particular address If any of these if true for any device out there (I think I have one in my computer that does the 1/ part in some cases), your code is unsafe. OG. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
- Re: VGA PCI IO port reservations H. Peter Anvin
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- Re: VGA PCI IO port reservations Richard B. Johnson
- Re: VGA PCI IO port reservations Russell King
- Re: VGA PCI IO port reservations Alan Cox
- Re: VGA PCI IO port reservations Richard B. Johnson
- Re: VGA PCI IO port reservations Russell King
- Re: VGA PCI IO port reservati... Richard B. Johnson
- Re: VGA PCI IO port reser... Russell King
- Re: VGA PCI IO port reser... Richard B. Johnson
- Re: VGA PCI IO port reser... Olivier Galibert
- Re: VGA PCI IO port reser... H. Peter Anvin
- Re: VGA PCI IO port reser... Alan Cox
- Re: VGA PCI IO port reser... Kai Henningsen
- Re: VGA PCI IO port reser... Marcus Sundberg
- Re: VGA PCI IO port reservati... H. Peter Anvin
- Re: VGA PCI IO port reser... Richard B. Johnson
- Re: VGA PCI IO port reservations Brian Gerst
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- Re: VGA PCI IO port reservations Jeff Garzik
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