Messages in this thread | | | Date | Sat, 20 Dec 2008 16:25:05 +0300 | From | Sergei Shtylyov <> | Subject | Re: [PATCH] ide: Fix ata_id_has_dword_io to return DWORD I/O support properly |
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Hello.
Robert Hancock wrote:
>>> This seems like a risky assumption... >> >> Its wrong on various counts >> >> - ata_id_major_version can't tell early ATA versions apart >> - on anything later than the early ISA IDE paddles (the ones that >> basically were just bus decoders) its invisible to the drive >> >> Except for legacy ISA bus controllers (and even there it is >> questionable) >> I would favour simply ignoring it. > > 32-bit IO wouldn't work on any ISA controller, would it? What happens > if you do 32-bit IO port access on something on the ISA bus?
TTBOM, depending on what's driven by device on -IOCS16, this will translate into 2, 3, or 4 cycles at the successive addresses. In case of the IDE data register, this should translate into one 16-bit cycle at 0x1x0, one 8-bit cycle at 0x1x1, and one 8-bit cycle at 0x1x2 which is of course not what anybody would want...
WBR, Sergei
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