Re: [RFC][PATCH 1/2] KVM: In-kernel PIT model

Jan Kiszka
2008-01-21T09:53:26Z

Yang, Sheng wrote:
> --- /dev/null
> +++ b/arch/x86/kvm/i8254.h
...
> +#define PIT_BASE_ADDRESS 0x40
> +#define SPEAKER_BASE_ADDRESS 0x61
> +#define PIT_MEM_LENGTH 4
> +#define PIT_FREQ 1193181

The PIT may not be limited to x86 platforms. So I would propose to make
the setup more generic and flexible. And I would move the code out of
arch/x86, just the speaker support should remain there.

I'm currently struggling with emulating a proprietary platform that has
(among other specialties...) a different PIT base frequency, and I
already had to patch user space qemu for customizable frequencies. Maybe
this kernel extension is a good chance to generalize the PIT setup, and
I would be happy to contribute to this if there is a consensus.

Jan

--
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux