On Fri, 2004-06-18 at 19:14, Ian Molton wrote:Bus remote is a red herring in this case. The only difference between this case and the ones supported by the coherent_dma_mask is that the constraint on placement of the allocated memory cannot be encoded as a bitmask.
On 18 Jun 2004 19:04:11 -0500
James Bottomley <James.Bottomley@xxxxxxxxxxxx> wrote:
Because the piece of memory you wish to access is bus remote.No, its *not*
my CPU can write there directly.
no strings attached.
the DMA API just only understands how to map from RAM, not anything
else.
I think you'll actually find that it is. OHCI is a device (representing
a USB hub), it's attached to the system by some interface that
constitutes a bus (the bus interface transforming the CPU access cycles
to device access cycles, translating interrupts etc.).