[U-Boot-Users] SII IDE and u-boot on MPC8540?

John Clemens john at deater.net
Sun Nov 23 20:46:44 CET 2003

This is along shot, I know, but I'm running out of ideas so I figured i'd
ask anyway..

So, my questions:
- has u-boot IDE ever been made to work with MMAP'd registers?
- how does one put a pci ide card into native pci mode, when the prog-if
  bits don't appear to be correct?
- does anyone have any experience doing something similar, or is everyone
  just using an isa bridge and legacy ports?
- please tell me i'm missing something obvious and all walk away in shame

And now, why i ask..

I'm using an MPC 8540 board and a SII 0680A PCI ide controller.. but I
can't get u-boot to talk to the IDE at all... It's almost as if the card
is insisting on coming up in "compatability mode" (i.e., listening at
ports 0x1f0 and 0x170) instead of "PCI-Native" mode where it should be
listening for PCI I/O cycles at PCI BAR0/1.  This is a problem because
there is no ISA space on this board, just a pci bridge.  (that is, if i'm
understanding things correctly, which is a big "if" at this point)

To make matters worse, the card is one of these cheepo software raid
controllers, so it identifies itself as class-code RAID instead of IDE, so
I'm not certain if the prog-if bits the ATA spec calls out apply or not
(prog-if is all 0, which would mean, via the spec, this chip can't do
pci-native mode, which just doesn't make sense.)

u-boot maps BAR0-3 at [IO] 0xe8000001, 0xe8000009, 0xe8000011, 0xe8000019.
According to the PCI ide controller programming interface document, in pci
native mode, these should be the base address of the ATA command blocks
and ATA control/dev blocks when the controller is in pci native mode.
It also maps BAR5 at [MEM] 0xe0000000.  dumping memory at e8000000 reveals
nothing interesting (mostly zero).  dumping memory at 0xe0000000 does
reveal something interesting (it appears to be memory mapped registers,
confirmed by the fact the Linux SII driver uses this as its mmio space)),
but trying several offsets there has led me nowhere.

any help, pointers to docs, anything would be greatly appreciated..
thanks in advance.

John Clemens          http://www.deater.net/john
john at deater.net     ICQ: 7175925, IM: PianoManO8
      "I Hate Quotes" -- Samuel L. Clemens

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