Subject: Re: port-mips/31915: provide centralized wired_map logic
To: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
From: SODA Noriyuki <soda@sra.co.jp>
List: port-mips
Date: 11/02/2005 00:16:56
>>>>> On Tue, 1 Nov 2005 23:30:27 +0900,
      Izumi Tsutsui <tsutsui@ceres.dti.ne.jp> said:

> which could use the functions in Garrett's patch.

If I recally correctly it couldn't.

> (hmm, it assumes bus_space functions won't use uvm/pmap functions?)

Yes. That's the main reason that it uses a wired mapping.
(Another reason is to reduce number of necessary TLB entries.)

> I'm not sure whether tga uses a new wired mapping or the PCI region
> already mapped in c_nec_pci.c:c_nec_pci_init(), though.

If I recall correctly, it doesn't use already mapped entry.
Rather, it use a new wired entry which is mapped via
arc_large_bus_space_compose_handle(), because the region of the
already mapped entry is	0x100000000 ... 0x100ffffff,
but the address of framebuffer begins from 0x108200000.
--
soda