while doing the block store workaround so we restore the correct
floating-point registers state in case of nested floating-point
operations resulting from nested interrupts. This allows the
VIS-based block copy/zero functions to be used on machines
requiring this workaround. Alternatively, we could take care of
saving the floating-point registers here, which would be more
inefficiently though and also involves turning off interrupts.
- It turns out that the SCZ_PCI_DMA_SYNC register doesn't work
like the TOMXMS_PCI_DMA_SYNC_PEND one (but more like the
corresponding register in of Hummingbird and Sabre bridges)
and writing the INO of the respective device to it causes a
Safari bus error. However, due to the Schizo errata I-23,
SCZ_PCI_DMA_SYNC can't be used as intended either, so remove
consistent DMA syncing for Schzio bridges for now, which means
that add-on cards with non-"sun4u compliant" (whatever that
means exactly) PCI-PCI-bridges should be avoided until the
proper workaround is implemented. [1]
Reported by: Michael Moll [1]