Subject: Re: kern/19435 and uncached memory
To: None <>
From: Izumi Tsutsui <>
List: tech-kern
Date: 01/17/2003 20:24:01
In article <> wrote:

> A workaround described in [1] is to disable cache of buffers.
> Do we have a standard way to allocate uncached memory on NetBSD?

In general, it _could_ be handled by bus_dmamem_map() API with
BUS_DMA_COHERENT flag if the architecture support it,
but I think there is no MI hook for each driver specific backend.

If you change bus_dmamem_map() on i386 with COHERENT flag
to map memory uncached, all other MI drivers are affected..

(If auich(4) only exists on i386, we could move auich driver
 under sys/arch/i386/pci and could replace bus_dma tag for it?)
Izumi Tsutsui