mtd_cpl question

Matthew Dillon dillon at
Tue May 24 18:57:31 PDT 2005

::     unsigned int	mtd_cpl[8];
::so that the mask can represent all 256 vectors defined in IA.
::Chuck Tuffli
::Agilent Technologies
:    It's constrained to 32 bits at the moment, because all the
:    interrupt handling assembly uses a bit-test-and-set (btsl)
:    and bit-test-and-reset (btrl) to mess with it.
:    The cpl will be going away soon anyway.  It's part of the
:    whole spl system and the spl system is going away.  I'm
:    working on fixing the various subsystems that depend on
:    e.g. splimp(), and other places... they will all be
:    replaced by critical sections and other mechanisms.

   I misspoke.  I meant that SPLs are going away soon.  CPLs, however,
   are not.  They are used to control delayed interrupt dispatch.  e.g.
   if an interrupt occurs while we are in a critical section we cannot
   dispatch or schedule the interrupt right then and there, we have to 
   delay the operation.

   So the cpl will have to be extended to 8 32 bit integers.

					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>

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