On 28-07-17, 10:36, Sébastien Szymanski wrote: > Setting the frequency higher than 528Mhz actually sets the ARM > clock to 528MHz. That's because PLL2 is used as the root clock when the > frequency is higher than 396MHz. > > cpupower frequency-set -f 792000 > > arm_clk_root on the CCM_CLKO2 signal is 528MHz instead of 792MHz. > > [ 61.606383] cpu cpu0: 396 MHz, 1025 mV --> 792 MHz, 1225 mV > > pll2 1 1 528000000 0 0 > pll2_bypass 1 1 528000000 0 0 > pll2_bus 3 3 528000000 0 0 > ca7_secondary_sel 1 1 528000000 0 0 > step 1 1 528000000 0 0 > pll1_sw 1 1 528000000 0 0 > arm 1 1 528000000 0 0 > > Fixes this by using the PLL1 as the root clock when the frequency is > higher than 528MHz. > > cpupower frequency-set -f 792000 > > arm_clk_root on the CCM_CLKO2 signal is now 792MHz as expected. > > [ 69.717987] cpu cpu0: 198 MHz, 950 mV --> 792 MHz, 1225 mV > > pll1 1 1 792000000 0 0 > pll1_bypass 1 1 792000000 0 0 > pll1_sys 1 1 792000000 0 0 > pll1_sw 1 1 792000000 0 0 > arm 1 1 792000000 0 0 > > Signed-off-by: Sébastien Szymanski <sebastien.szyman...@armadeus.com> > --- > drivers/cpufreq/imx6q-cpufreq.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-)
Looks fine to me: Acked-by: Viresh Kumar <viresh.ku...@linaro.org> @Shawn: Can you also confirm if this looks fine to you ? -- viresh
