>> 1) Figure out what exactly is going on; > > I thought we were past that.
We are not. > The startup sequence leaves the device in a > bad > state (writing 1000 times per second to memory that the kernel believes is > not in use), so it needs to be given a reset command before the kernel > tries > to use that memory. The question now is what causes the firmware to do that, and then what is the best way to stop it from doing that. >> > The big question that I'm still stumbling over is how to access the >> device >> > registers. The "reg" property looks like this: >> >> You should look at "assigned-addresses", not "reg". Well, >> you first need to look at "reg" to figure out what entry >> in "assigned-addresses" to use. Ignore this part, I was confused. > The properties look like this: > > /p...@80000000/u...@5/assigned-addresses > 02002810 00000000 80000000 00000000 00001000 Lovely, incorrect data (it should start with 82002810, i.e., not relocatable -- it is already an assigned address!). This means: 32-bit MMIO address space for bus 0 dev 5 fn 0, first BAR; assigned to address 80000000; size is 1000. You could try a boot script like this: dev /pci 0 ffff04 DO 0 i config-w! -100 +LOOP device-end which should disable all PCI devices on all busses, on that PCI host bus (it disables every device behind pci-pci bridges separately, as long as every such bridge has a higher secondary bus number than primary bus number; if you only want to disable everything on the root bus (which should be sufficient), use ff04 instead of ffff04). Segher _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
