kevin diggs <diggskevin38@xxxxxxxxx> writes:
> I may be wearing out my welcome, but:
>
> I tried to use (in a header file):
>
> /**
> * get_PLL: - return current value of PLL register (HID1)
> *
> * This returns the current value of the PLL configuration register (HID1).
> */
> static inline volatile unsigned int get_PLL(void)
> {
> unsigned int ret;
>
> __asm__ __volatile__ ("mfspr %0,%1":
> "=r"(ret):
> "i"(SPRN_HID1)
> );
>
> return ret;
> }
>
> to make sure that this function did not get moved or optimized away.
> 4.1.2 generated a warning (Linux kernel compile: warning -> error).
>
> cc1: warnings being treated as errors
> In file included from arch/powerpc/kernel/cpu/cpufreq/cf750gx.c:37:
> /mnt/mnt3/linux-2.6.36/arch/powerpc/include/asm/pll.h:84: warning:
> type qualifiers ignored on function return type
The warning is correct: volatile is ignored on a function return type.
To avoid the warning, write
static inline unsigned int get_PLL(void)
If that does not answer your question, what are you trying to do?
Ian
