Subject: Re: netbooting an OF 1.0.5 macppc with SUNW,hme on PCI
To: None <email@example.com>
From: Izumi Tsutsui <firstname.lastname@example.org>
Date: 04/05/2000 20:58:54
> Does PCI isp SCSI support DMA with big endian hosts?
> If no, some byte-swap macros are needed in /sys/dev/isp.c
> for DMA transfers, but they would break SBUS isp code.
> I think hme_pci might have the same problem.
> UltraSPARC PCI already does various dances to get accesses
> performed in the correct manner...
Well, then does the PCI-host bridge on sparc64 do byte-swapping
even when the PCI bus-master accesses memory on its host via DMA?
Other PCI drivers which contain byte-swapping code would not
work on sparc64?
BTW, it seems that /sys/dev/ic/hme.c has bus_dmamem_alloc() and
bus_dmamem_map() but no bus_dmamap_load() nor bus_dmamap_sync()...
Anyway, does hme pass non byte-stream (like u_int32_t) data via DMA?
if no, no byte-swapping code is needed even on other big endian archs.