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Re: PCI Address Decode querry!!!
I expect all PCI-bridges will do smart things not to generate dual address
cycle when ad[63:32] == 0.
The following code would save address decode time without loss of any
During address cycle, generate match signal for 32-bit address BAR:
March = ad[31:12] == Bar[31:12];
If a dual address cycle is generated first, never generate match signal for
32-bit address BAR.
I would like to hear other's opinions.
Micro Memory Inc., CA 91311, US.
----- Original Message -----
From: Monish Shah <firstname.lastname@example.org>
To: Narayan Kulshrestha <email@example.com>; <firstname.lastname@example.org>
Sent: Sunday, July 09, 2000 9:18 PM
Subject: Re: PCI Address Decode querry!!!
> > Hello !!
> > When PCI Bus 64 bit Bus is it mendatory for all the BARS to be 64 bit??
> > Or is it like this, for a 32 bit BAR match??
> > match_occured = (ad[63:32] == 0 ) && (mask[31:12] & ad[31:12] ==
> > Bar[31:12])
> Yes, except that if AD[63:32]==0, you won't get a DAC (dual address
> > Please give some real Idea on it!!
> > Best rgds
> > Narayan
> Monish Shah
> Ascent Software