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    SubjectRe: [PATCH 05/11] ST SPEAr: Added clock framework for SPEAr platform and machines
    2010/3/11 Shiraz HASHIM <>:
    > On 3/11/2010 12:30 PM, Linus Walleij wrote:
    >> 2010/3/3 Viresh KUMAR <>:
    >> (...)
    >>> +       if (unlikely(clk->flags & RESET_TO_ENABLE))
    >>> +               val &= ~(1 << clk->en_reg_bit);
    >>> +       else
    >>> +               val |= 1 << clk->en_reg_bit;
    >>> +       writel(val, clk->en_reg);
    >> I don't understand one bit of this. (...)
    > The intention to use RESET_TO_ENABLE flag is to generalize clock
    > enable/disable across platforms.

    I misread the entire thing, there was some bad parsing inside my head...
    Sorry about this.

    >> OMAP uses CPUfreq but that is really about the CPU. As it happens, all
    >> their clk:s always change frequency at the same operating points as the
    >> CPU. So they can have pre/post calls from CPUfreq in their code, but
    >> this will not work with things like PrimeCells where other users of the cell
    >> may not have operating points correlated with CPU operating points.
    >> (I'm not requesting you to solve this problem, more to be aware of it.)
    > I think generally in embedded systems (at least in our case :) ) the CPU clock
    > itself is not completly independent. It is generally tied with some system
    > clock, which has an impact on bus and peripheral clocks. In that sense cpu freq
    > would be a better mean to notify frequency change.
    > In any case, clock framework don't intend to do it. It only need to reflect
    > correct system state. Is this understanding correct?

    Currently it's like that but I think clk really needs a frequency change
    notification mechanism. I will have to deal with it some day I think :-/

    Linus Walleij
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