From: Peter DOT Henn AT t-online DOT de (Peter)
Newsgroups: comp.os.msdos.djgpp,comp.sys.intel
Subject: PCI read burst from CPU
Date: 22 Feb 1998 15:32:19 GMT
Organization: T-Online
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To: djgpp AT delorie DOT com
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Hello PCI freaks,
I want to read the memory from a PCI adapter (e.g. Graphic card)
as fast as possible via PCI read bursts. Does there exist any
C or Assembler source?

Write burst no problem:
If I use the "_movedatal" from the "sys/movedata.h" of the DJGPP
package for PCI write transactions, I see PCI write bursts on a LA. 
The interface chip saves the address/data pairs and put them as
burst transaction on the PCI bus.
But this will not work during a read transfer, because the PCI
interface chip waits after sending the address to PCI bus until
it gets the target answer - the requested read data.

Problem read burst:
Possible there exist a way to use the CPUs cache to generate PCI
burst transfers. Naturally this requires a invalidation of the
cacheline before using them.

Please send hints and short code examples only to this newsgroup
and do not try my email.

Thanks & regards,
Peter