ARM clock API to PowerPC

Russell King rmk at
Sat Aug 15 22:43:47 EST 2009

On Fri, Aug 14, 2009 at 10:07:44PM +1000, Benjamin Herrenschmidt wrote:
> My idea is that struct clock would contain function pointers for the
> enable/disable/get_rate/ etc... methods

If you look at OMAP, doing that gets very expensive, both in terms of
number of lines of code, size of structure and maintainence thereof.
Neither does a 'clk_ops' structure containing all of the function
pointers work either for OMAP (OMAP has such a structure just for
enable and disable methods, of which there are about two or three to
chose from, but the rounding, set_rate and propagation methods are
per-clk.  This balance seems to work well for OMAP.)

FYI, there are 140 struct clk definitions for OMAP24xx, and 215 for
OMAP34xx, all statically initialized.  See arch/arm/mach-omap2/clock?4xx.h

Russell King

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