>>>>> "Maciej" == Maciej W Rozycki <macro@xxxxxxxxxxxxxx> writes: Maciej> On Mon, 18 Oct 2004, Jes Sorensen wrote: >> Dual address cycles, ie. 64 bit addressing is fscked on the 1250 >> from what I remember. Correct way to work around this is to stick >> all physical memory outside the 32 bit space into ZONE_HIGHMEM - >> had a patch for 2.4, but I lost it ages ago ;-( Maciej> The BCM1250A's PCI is obviously 32-bit only (the host bridge Maciej> is explicitly documented not to support DACs), but you need to Maciej> use 64-bit addressing to access the whole 4GB range -- the bus Maciej> is decoded starting from 0xf800000000 and 0xf900000000, with a Maciej> different byte lane swapping policy for each of these areas. Maciej> For limited access for 32-bit software, you can use alternate Maciej> mappings at 0x40000000 and 0x60000000, but they provide only Maciej> 512MB of space each. Yeah it seems to be documented, it's highly unfortunate that anybody will release a chip which doesn't support DAC but will support memory outside the 4GB range. I'd be highly embarrassed if I had done the chip, but thats just me. I think you are right about the HT part. Cheers, JEs
