Jiri Slaby wrote:
Hello,
I have a driver written for 2.4 + RT patches with FP support. I want
it to work
in 2.6. How to implement FP? Has anybody developped some "protocol"
between KS
and US yet? If not, could somebody point me, how to do it the best --
with low
latency.
The device doesn't generate irqs *), I need to quickly respond to
timer call,
because interval between two posts of data to the device has to be
equal as much
as possible (BTW is there any way how to gain up to 5000Hz).
I've one idea: have a thread with RT priority and wake the app in US
waiting in
read of character device when timer ticks, post a struct with 2 floats
and
operation and wait in write for the result. App computes, writes the
result, we
are woken and can post it to the device. But I'm afraid it would be
tooo slow.
*) I don't know how to persuade it (standard PLX chip with unknown
piece of
logic behind) to generate, because official driver is closed and _very_
expensive. Old (2.4) driver was implemented with RT thread and timer,
where FP
is implemented within RT and computed directly in KS.
So 2 questions are:
1) howto FP in kernel
kernel_fpu_begin();
c = d * 3.14;
kernel_fpu_end();
--
error compiling committee.c: too many arguments to function
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
