I think that speculative loads may be the answer.
wuming wrote:
----- Original Message -----
From: "Gleb O. Raiko" <raiko@xxxxxxxxxxxx>
To: "wuming" <wuming@xxxxxxxxx>
Cc: <linux-mips@xxxxxxxxxxxxxx>
Sent: Monday, December 20, 2004 4:43 PM
Subject: Re: problem about dma
In 2.4, memcpy's prefetch may (and, in practice, do, no smiles, it cost
me a lot of time to realize) access that memory. I though it has been
fixed in 2.6 someday.
Regards,
Gleb.
Thank you! :)
But I think it is not the only reason, because the CPU on my platform does not
support the "pref" instruction. So, memcpy's prefetch may have no effect on that
arrange of memory.