What do you mean by "synthesizing a jump"?
My CPU is a 5Kc and it has a DIVEC which is set to the mipsIRQ function in
/arch/mips64/mips-boards/generic/mipsIRQ.S to handle interrupts. But I still do
not understand the address manipulation which is done before storing the
function pointer (handler).
Thanks
Lars Munch
On Sat, Sep 01, 2001 at 11:54:26AM -0400, Bradley D. LaRonde wrote:
> Looks like it is synthesizing a jump (j) instruction to forward interrupt
> exceptions to the interrupt handler for cpus that have a dedicated interrupt
> vector (DIVEC). arch/mips/kernel/setup.c sets the DIVEC option for certain
> cpus.
>
> Regards,
> Brad
>
> ----- Original Message -----
> From: "Lars Munch" <lars@segv.dk>
> To: <linux-mips@oss.sgi.com>
> Sent: Saturday, September 01, 2001 10:58 AM
> Subject: set_except_vector question
>
>
> > Hi
> >
> > I have been looking at the set_except_vector function in
> > arch/mips[64]/kernel/traps.c and wondering why the handler
> > address is changed/recalculated before it is stored:
> >
> > *(volatile u32 *)(KSEG0+0x200) = 0x08000000 | (0x03ffffff & (handler >>
> 2));
> >
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >
> > Could someone please enlighten me?
> >
> > Thanks
> > Lars Munch
> >
>
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