unsigned int get_PLL_range(unsigned int range, unsigned int config)
{
range = range * 8 + 23;
return ((config << range) | (config >> (32 - range))) & 3;
}
The special pattern ((a << n) | (a >> (32 - n))) is recognized by
gcc as
a rotate operation.
It's only valid for 1 <= n <= 31 though
Kevin Diggs <[EMAIL PROTECTED]> writes:
> Jeremy Kerr wrote:
>> Hi Kevin,
>>
>>
>>> /*
>>> * Turn r3 (range) into a rotate count for the selected
>>>range. * 0 -> 23, 1 -> 31
>>> */
>>> __asm__ __volatile__ ( "slwi %0,%0,3\n"
>>> "
Jeremy Kerr wrote:
Hi Kevin,
/*
* Turn r3 (range) into a rotate count for the selected
range. * 0 -> 23, 1 -> 31
*/
__asm__ __volatile__ ( "slwi %0,%0,3\n"
"addi %0,%0,23\n"
"rlwnm %0,%1,%0,30,31
Hi Kevin,
> /*
> * Turn r3 (range) into a rotate count for the selected
> range. * 0 -> 23, 1 -> 31
> */
> __asm__ __volatile__ ( "slwi %0,%0,3\n"
> "addi %0,%0,23\n"
> "rlwnm %0,%1,%0,30,31\n"
On Tue, 2008-08-05 at 17:20 -0700, Kevin Diggs wrote:
> Hi,
>
> thats bad right? Because the "addi 0, 0, 23" will not work as expected
> because of the "special property" of r0. FYI: The first three lines
> after the "#APP" are from a similar function get_PLL_ratio().
>
> Is there a way
Hi,
If I have:
inline unsigned int get_PLL_range(unsigned int range, unsigned int
config)
{
unsigned int ret;
/*
* Turn r3 (range) into a rotate count for the selected range.
* 0 -> 23, 1 -> 31
*/
__asm__ __volatile__ ( "slwi %0,%0,3\n"
