Subject: Re: port-mips/31915: provide centralized wired_map logic
To: None <>
From: Izumi Tsutsui <>
List: port-mips
Date: 10/28/2005 04:01:19
[well, please don't quote whole messages. all messages are filed in gnats]

In artcile <> wrote:

> I've thought some more about this.  I really think, pretty strongly, 
> that it is wrong for the wired_map logic to manage its own extents.

Well, we don't have to map device space always by wired map functions.
The lower wired map layer could have its own extent, and the upper
bus_space(9) layers could also manage their regions by own extents.

If required physical address is already mapped to VA by the other
request, upper layer can choose the VA range already allocated
rather than create another wired map.
In sys/arch/arc/arc/bus_space_{sparse,large}.c, wired_map function is
called only if the requested PA range is too large for KSEG2
mappings and it has not been mapped by another wired_map.
Isn't it okay? (maybe I overlook something though...)
Izumi Tsutsui