Subject: Re: port-mips/31915: provide centralized wired_map logic
To: None <tsutsui@netbsd.org, gnats-admin@netbsd.org,>
From: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
List: netbsd-bugs
Date: 10/27/2005 19:02:02
The following reply was made to PR port-mips/31915; it has been noted by GNATS.

From: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
To: garrett_damore@tadpole.com
Cc: gnats-bugs@NetBSD.org, port-mips@NetBSD.org,
	tsutsui@ceres.dti.ne.jp
Subject: Re: port-mips/31915: provide centralized wired_map logic
Date: Fri, 28 Oct 2005 04:01:19 +0900

 [well, please don't quote whole messages. all messages are filed in gnats]
 
 In artcile <43611BFA.3030306@tadpole.com>
 garrett_damore@tadpole.com 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