linux-mips
[Top] [All Lists]

Re: Re : where to set the BEV to normal of status in kernel source?

To: Florian DELIZY <florian.delizy@sagem.com>
Subject: Re: Re : where to set the BEV to normal of status in kernel source?
From: "Kevin D. Kissell" <kevink@mips.com>
Date: Fri, 02 Dec 2005 14:52:53 +0100
Cc: linux-mips@linux-mips.org
In-reply-to: <OF5E474B6B.A94FD801-ONC12570CB.004B3FC5-C12570CB.004B4D6D@sagem.com>
Original-recipient: rfc822;linux-mips@linux-mips.org
References: <OF5E474B6B.A94FD801-ONC12570CB.004B3FC5-C12570CB.004B4D6D@sagem.com>
Sender: linux-mips-bounce@linux-mips.org
User-agent: Mozilla Thunderbird 1.0.6 (X11/20050716)
The BEV bit of Status is cleared by the macro setup_c0_status_pri which
is invoked in kernel_entry.  See arch/mips/kernel/head.S.  It's of course
possible that a bootloader will already have cleared it, but it should not
be necessary.  grep is your friend.  ;o)

                Regards,

                Kevin K.

Florian DELIZY wrote:
Subject : where to set the BEV to normal of status in kernel source?

i don't find it in load_mmu(), who can point out for me?
thanks!


Well, if you are speaking about the BEV flag from the Status (SR) register (CP0_STATUS aka $12 of the 1st coprocessor) then it controls the interruption/exception handler place, I don't see the relation with mmu ...

is that must be set in bootloader?


OK, I see, it should be set to 0 by the boot loader so that the TLB exceptions (related to the MMU) goes in RAM. So the kernel does not change it actually and hope the boot loader did.

-- Florian Delizy








<Prev in Thread] Current Thread [Next in Thread>