On 16-11-24 01:34 PM, Mark Lord wrote: >From tracing through the powerpc arch code, this is the buffer that > is being directly DMA'd into. And the USB layer does an invalidate_dcache > on that entire buffer before initiating the DMA (confirmed via printk).
Slight correction: the invalidate_dcache_range() is only done when using kmalloc'd buffers. I have converted the driver here to use usb_alloc_coherent() instead, so that now gets skipped since the memory is never cached.
