Re: [Qemu-devel] Re: [PATCH 0/5] *** SUBJECT HERE ***

[Paul Brook]

> >  One example is the openpic page size pointed out downthread.
> >
> >  What about something like this (doesn't change all the places affected
> >  by your series, compile-tested only)?
> 
> In general (with vmport and maybe virtio as the only exceptions), the
> devices have no business knowing _any_ CPU properties, like page size
> or endianness. If there really was a device that really cared about
> CPU page size, the size should be also known by the board and should
> be passed down from there via qdev property. Byte swapping should be
> handled by the bus, bus controller or memory controller.

I agree. Most of the uses of TARGET_PAGE_SIZE are simply an optimization - 
it's a convenient buffer size for DMA transfers. Other uses are probably 
incorrect.

None of virtio.c, virtio-{blk,net,serial} or virtio-{pci,syborg} should know 
about CPU properties. Virtio-s390 might because it's implementing magic CPU 
instructions.

Paul