Alexey Brodkin <Alexey.Brodkin at synopsys.com> wrote on 02.02.2016 13:53:26:
>
> Adding Christian for Abilis TB10x clocks review.
>
> On Tue, 2016-02-02 at 16:28 +0530, Vineet Gupta wrote:
> > From: Alexey Brodkin <abrodkin at synopsys.com>
> >
> > UARTs usually have fixed clock so we're switching to use of
> > constant values instead of something derived from core clock
> > frequency.
> >
> > Among other things this will allow us to get rid of
> > arc_{get|set}_core_freq() and switch to generic clock
> > framework later on.
> >
> > Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
> > Signed-off-by: Vineet Gupta <vgupta at synopsys.com>
> > ---
> > arch/arc/kernel/devtree.c | 6 ++----
> > 1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
> > index 7e844fd8213f..e155126c79b1 100644
> > --- a/arch/arc/kernel/devtree.c
> > +++ b/arch/arc/kernel/devtree.c
> > @@ -28,14 +28,12 @@ unsigned int __init arc_early_base_baud(void)
> >
> > static void __init arc_set_early_base_baud(unsigned long dt_root)
> > {
> > - unsigned int core_clk = arc_get_core_freq();
> > -
> > if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
> > - arc_base_baud = core_clk/3;
> > + arc_base_baud = 166666667; /* Fixed 166.7MHz clk (TB10x) */
Actually, (int)core_clk/(int)3 is 166666666 not 166666667.
I seem to remember that this rounding detail did make a difference at some
point. Unluckily, the details are long forgotten in the mist of time...
> > else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp"))
> > arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x) */
> > else
> > - arc_base_baud = core_clk;
> > + arc_base_baud = 50000000; /* Fixed default 50MHz */
> > }
> > #else
> > #define arc_set_early_base_baud(dt_root)
>
> -Alexey
