[pci] Question about PCI 2.2 Spec

["llbutcher" <llbutcher@veriomail.com>]

Anyone want to help me try to understand an obscure detail of
the PCI spec?

Assume that you have a Target Interface.  That interface sees
a read, and ends it with retry because it should be serviced as
a delayed read.

Now assume that a Config Reference comes in and turns off
Target Mode.

After a while, Target Mode is turned back on with another Config
Write.

Should the Delayed Read in progress be ditched when the Config
bit tirhs off target references, or should it be placed into suspended
animation and restarted when the Target is re-enabled.

If it is suspended and restarted, what can the PCI Configuration
Master do totally shut down the target, to make sure that it starts
from scratch.


Similar question for the Master.  Assume that the Master starts a
PCI reference which partially completes, then gets a Retry.

Now the Master Enable bit in the Config Register is turned off.

Should the Burst be remembered, to be completed when the
Master is enabled later?  Or should it be ditched?  (This might
result in a Target hang and Delayed Read Timeout much later,
another bad thing.)

If the Master is suspended and restarted, what can the Configuration
Master do to totally punt all PCI Master Activity?

Can anyone help me out by quoting the PCI version 2.2 Section
Number which addresses this issue?

Thanks:

Blue Beaver


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