Re: struct page to 36 (or 64) bit bus address?

From: Gerd Knorr (kraxel@bytesex.org)
Date: Sat Aug 11 2001 - 02:09:02 EST

Next message: Nick Kurshev: "Can't compile linux-2.4.8"
Previous message: H. Peter Anvin: "Re: [ANNOUNCE] Gujin graphical bootloader 0.4"
In reply to: David S. Miller: "Re: struct page to 36 (or 64) bit bus address?"
Next in thread: Steffen Persvold: "Write Combining (Write Coalescing) on memory mapped I/O on IA64."
Reply: Steffen Persvold: "Write Combining (Write Coalescing) on memory mapped I/O on IA64."
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Fri, Aug 10, 2001 at 02:58:36PM -0700, David S. Miller wrote:
>
> I'm using the patch below (pulled out of Jens Axboe's bio
> patches, i386 only).
>
> Are you sure you aren't missing anything in this patch? For example,
> one can't use the patch you've provided for 64-bit DMA unless the
> dma_addr_t type is made larger.

It only allows to use the full 32 bit address range for DMA. Without
the patch I'm limited to direct mapped memory (i.e. < ~900MB on i386).
With the patch highmem below 4GB can be used too.

Jens's bio patches don't have support for 64-bit DMA (at least not the
version I've used to build that patch). Because the bt848/878 chips
are 32-bit devices only I havn't even tried to fix that...

Gerd

-- 
Damn lot people confuse usability and eye-candy.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Next message: Nick Kurshev: "Can't compile linux-2.4.8"
Previous message: H. Peter Anvin: "Re: [ANNOUNCE] Gujin graphical bootloader 0.4"
In reply to: David S. Miller: "Re: struct page to 36 (or 64) bit bus address?"
Next in thread: Steffen Persvold: "Write Combining (Write Coalescing) on memory mapped I/O on IA64."
Reply: Steffen Persvold: "Write Combining (Write Coalescing) on memory mapped I/O on IA64."
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

This archive was generated by hypermail 2b29 : Wed Aug 15 2001 - 21:00:37 EST