leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Tegra: clk: always use find_best_divider() for periph clocks

Browse Source 
When adjusting peripheral clocks always use find_best_divider()
instead of clk_get_divider() even when a secondary divider is not
available.  In the case where is requested clock is too slow to be
derived from the parent clock this allows a best effort to get close
to the requested clock.

This comes up for commands like "sf" where the user can pass a clock
speed on the command line or "sspi" where the clock is hardcoded to
1MHz, but the Tegra114 SPI controller can't go that low.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
This commit is contained in:
Allen Martin 2013-05-10 16:56:55 +00:00 committed by Tom Warren
parent d56273de15
commit a51f7de161
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/arm/cpu/tegra-common/clock.c
View File

@ -321,17 +321,17 @@ unsigned clock_adjust_periph_pll_div(enum periph_id periph_id,
unsigned effective_rate;
int mux_bits, divider_bits, source;
int divider;
int xdiv = 0;
/* work out the source clock and set it */
source = get_periph_clock_source(periph_id, parent, &mux_bits,
&divider_bits);
divider = find_best_divider(divider_bits, pll_rate[parent],
rate, &xdiv);
if (extra_div)
divider = find_best_divider(divider_bits, pll_rate[parent],
rate, extra_div);
else
divider = clk_get_divider(divider_bits, pll_rate[parent],
rate);
*extra_div = xdiv;
assert(divider >= 0);
if (adjust_periph_pll(periph_id, source, mux_bits, divider))
return -1U;