From mboxrd@z Thu Jan 1 00:00:00 1970 From: viresh.kumar@linaro.org (Viresh Kumar) Date: Wed, 2 Aug 2017 09:19:51 +0530 Subject: [PATCH 1/1] cpufreq: imx6q: imx6ull: use PLL1 for frequency higher than 528MHz In-Reply-To: <1501230993-15812-1-git-send-email-sebastien.szymanski@armadeus.com> References: <1501230993-15812-1-git-send-email-sebastien.szymanski@armadeus.com> Message-ID: <20170802034951.GA31169@vireshk-i7> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 28-07-17, 10:36, S?bastien 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: S?bastien Szymanski > --- > drivers/cpufreq/imx6q-cpufreq.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) Looks fine to me: Acked-by: Viresh Kumar @Shawn: Can you also confirm if this looks fine to you ? -- viresh