jkh weird problem (reading pci device memory)
John-Mark Gurney
gurney_j at resnet.uoregon.edu
Mon Aug 7 22:05:52 UTC 2006
John Baldwin wrote this message on Mon, Aug 07, 2006 at 15:27 -0400:
> sc->cfg_table.signature = letoh32(bus_read_4(sc->bar.res, 0));
> sc->cfg_table.version = letoh16(bus_read_2(sc->bar.res, 4));
> sc->cfg_table.dummy = bus_read_1(sc->bar.res, 5);
Note that this may or may not be correct... the bus_read_X macros
do endian conversion if the bus is of different endianness than the
processor arch... So if the device is on a PCI bus, and the machine
is sparc64, the bus_read_X will already be swapped as necessary... If
you don't want the byte swapping to be done for you, there are the
_stream versions... The are useful for transfering data like disk
data that needs to maintain the same order...
--
John-Mark Gurney Voice: +1 415 225 5579
"All that I will do, has been done, All that I have, has not."
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