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 --- arch/arm/cpu/tegra-common/clock.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/arm/cpu/tegra-common/clock.c b/arch/arm/cpu/tegra-common/clock.c index 9156d00..268fb91 100644 --- a/arch/arm/cpu/tegra-common/clock.c +++ b/arch/arm/cpu/tegra-common/clock.c @@ -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, ÷r_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;