Re: Problem with IRQ0 in SH7705

[Magnus D. <mag...@gm...>]

Hi there,

On 10/3/07, Cmmn Ml <cm...@ya...> wrote:
> This may not be something interesting to the general community, because
> SH7705 is not now widley used. But if someone can give some thoughts, it
> will be a great help for me.

[snip]

> The value 32 is the irq number I'm requesting (which is relevent to IRQ0)
> and I don't know what is 7. FYI : I'm setting the priority of IRQ0 as 7 in
> IPRC register.
>
> Were there any known problems in 2.6.16 kernel with IRQ0 in 7705, If anyone
> can give some thoughts on this, it'll be a great.

I recommend you to use a more recent kernel to begin with. Many things
have changed since 2.6.16.

I suspect that older kernels didn't provide any masking and unmasking
code for IRQ0. There is at least no such code in this old version:

http://git.kernel.org/?p=linux/kernel/git/lethal/sh-2.6.git;a=blob;f=arch/sh/kernel/cpu/sh3/setup-sh7705.c;h=a55b8ce2c54c46e156319f674928e36f07bd7f15;hb=68abdbbb03476a60d932eeba0035dd5069afec38

There may be some board specific code that handles IRQ0 though, I'm
not sure. But anyway, you need some code that masks and unmasks IRQ0
in IPRC. There is no IRQ0 interrupt in ipr_irq_table above so I
suspect it is not supported in older kernels. The new intc tables
should support that interrupt source out of the box though.

Hope this helps!

/ magnus