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List:       linux1394-devel
Subject:    OHCI physical upper bound
From:       Steve Kinneberg <kinnebergsteve () acmsystems ! com>
Date:       2004-01-26 23:47:57
Message-ID: 1075160877.6862.230.camel () stevek ! sncorp ! intranet ! com
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Is there a reason why ohci1394.c sets the physical upper bound register
to 0xffff0000 (for an address of 0xffff00000000?  It effectively makes
the majority of the 1394 address space useless as requests to addresses
in the range 0x000000000000 to 0xffff00000000 are not passed on through
the async receive context.

Also, the OHCI spec says the the physical upper bound register is
optional, and if not present, it is effectively set to 0x00010000 (for
an address of 0x000100000000).  The value 0xffff0000 is maximum allowed
to be set by software.  Wouldn't it make more sense to set it to the
same value as OHCI chips that don't support writes to the physical upper
bound register?
 
-- 
Steve Kinneberg
ACM Systems
(916) 463-7987
kinnebergsteve at acmsystems dot com




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