Re: How can I link the kernel with libgcc ?

From: Lee Revell
Date: Thu Mar 09 2006 - 22:22:57 EST


(added alsa-devel to cc:)

On Thu, 2006-03-09 at 19:01 -0800, Carlos Munoz wrote:
> >Audio drivers should never have to directly manipulate the samples -
> >they just manage the DMA buffers and interrupts and wake up the process
> >at the right time. Mixing, routing, volume control, DSP go in
> >userspace.
>
> Unfortunately, the driver needs to populate several coefficient tables
> for the hardware to perform silence suppression and other advance
> features. The values for these tables are calculated using log10
> operations. I don't see a clean way to push these operations to user
> space without the need for custom applications that build the tables and
> pass them to the driver.

Unless you can do it with fixed point math, or use a static table, you
might have to do just that, with a sysfs interface. For example the
emu10k1 driver uses an ioctl interface to upload code to the built in
(floating point) DSP. But new ioctls are frowned upon...

Lee

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