Hi Dmitry Finally, I came around giving this a try again on the Colibri T20 and Apalis/Colibri T30. Overall, works like a charm and you may add the following to the entire series: On Wed, 2019-12-18 at 23:21 +0300, Dmitry Osipenko wrote: > PLLX may be kept disabled if cpufreq driver selects some other clock > for > CPU. In that case PLLX will be disabled later in the resume path by > the > CLK driver, which also can enable PLLX if necessary by itself. Thus > there > is no need to enable PLLX early during resume. Tegra114/124 CLK > drivers do > not manage PLLX on resume and thus they are left untouched by this > patch. > > Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> Tested-by: Marcel Ziswiler <marcel@xxxxxxxxxxxx> Tested-on: Colibri T20, Apalis/Colibri T30 on resp. EvalBoards > --- > arch/arm/mach-tegra/sleep-tegra30.S | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach- > tegra/sleep-tegra30.S > index 9a20c93abe48..4f073869b8ac 100644 > --- a/arch/arm/mach-tegra/sleep-tegra30.S > +++ b/arch/arm/mach-tegra/sleep-tegra30.S > @@ -358,7 +358,6 @@ _no_pll_iddq_exit: > > pll_enable r1, r0, CLK_RESET_PLLM_BASE, CLK_RESET_PLLM_MISC > pll_enable r1, r0, CLK_RESET_PLLC_BASE, CLK_RESET_PLLC_MISC > - pll_enable r1, r0, CLK_RESET_PLLX_BASE, CLK_RESET_PLLX_MISC > > _pll_m_c_x_done: > pll_enable r1, r0, CLK_RESET_PLLP_BASE, CLK_RESET_PLLP_MISC > @@ -368,8 +367,18 @@ _pll_m_c_x_done: > pll_locked r1, r0, CLK_RESET_PLLP_BASE > pll_locked r1, r0, CLK_RESET_PLLA_BASE > pll_locked r1, r0, CLK_RESET_PLLC_BASE > + > + /* > + * CPUFreq driver could select other PLL for CPU. PLLX will be > + * enabled by the Tegra30 CLK driver on an as-needed basis, see > + * tegra30_cpu_clock_resume(). > + */ > + cmp r10, #TEGRA30 > + beq _pll_m_c_x_locked > + > pll_locked r1, r0, CLK_RESET_PLLX_BASE > > +_pll_m_c_x_locked: > mov32 r7, TEGRA_TMRUS_BASE > ldr r1, [r7] > add r1, r1, #LOCK_DELAY Unfortunately, that one does no longer apply after the following patch recently got applied on Wed Jan 8: commit 1a3388d506bf ("ARM: tegra: Enable PLLP bypass during Tegra124 LP1") Thanks! Cheers Marcel