Time to kill fdc ?

John Baldwin jhb at freebsd.org
Fri Feb 15 13:47:39 UTC 2013


On Thursday, February 14, 2013 9:45:22 pm Adrian Chadd wrote:
> On 14 February 2013 13:35, John Baldwin <jhb at freebsd.org> wrote:
> 
> > ISA bounces anything above 16GB.  They are bouncing.  I know it works for some
> > people as I fixed a bug in the ISA bounce buffer code somewhat recentish:
> 
> You mean 16MB, right?

Yes, doh!

> There's a secondary bounce buffer thing needed for 32 bit PCI devices
> on a 64 bit machine with > 4 GB of physical RAM, right?

That is handled via the tags passed to bus_dma.  ISA DMA doesn't currently
use bus_dma but reimplements its own bounce handling.

-- 
John Baldwin


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