John Rose johnrose at
Tue Feb 22 12:21:34 EST 2005

During init, pSeries_request_regions() blindly requests ioports:
00000000-0000001f : dma1
00000020-0000003f : pic1
00000040-0000005f : timer
00000060-0000006f : reserved (no i8042)
00000080-0000008f : dma page reg
000000a0-000000bf : pic2
000000c0-000000df : dma2

If I understand correctly, this is necessary for legacy ISA support.  A
system with purely virtual I/O would not need these reservations.  If I
should skip their reservation conditionally, should I check for the
mere existence of physical I/O?  Or for the existence of an ISA node?


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