Hello Tudor, > -----Original Message----- > From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx> > Sent: Wednesday, July 24, 2024 8:18 PM > To: Sunyeal Hong <sunyeal.hong@xxxxxxxxxxx>; Krzysztof Kozlowski > <krzk@xxxxxxxxxx>; Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>; Chanwoo > Choi <cw00.choi@xxxxxxxxxxx>; Alim Akhtar <alim.akhtar@xxxxxxxxxxx>; > Michael Turquette <mturquette@xxxxxxxxxxxx>; Stephen Boyd > <sboyd@xxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>; Conor Dooley > <conor+dt@xxxxxxxxxx> > Cc: linux-samsung-soc@xxxxxxxxxxxxxxx; linux-clk@xxxxxxxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v4 2/4] arm64: dts: exynos: add initial CMU clock > nodes in ExynosAuto v920 > > Hi, Sunyeal, > > I quickly skimmed over the series and I fail to see where/how the HW auto > clock gating is enabled/configured. Would you please add more details on > how this works? > The HW auto clock gating function is activated in the bootloader stage. So we don't have to control it in the kernel. > On 7/22/24 11:33 PM, Sunyeal Hong wrote: > > Add cmu_top, cmu_peric0 clock nodes and switch USI clocks instead of > > dummy fixed-rate-clock. > > > > Signed-off-by: Sunyeal Hong <sunyeal.hong@xxxxxxxxxxx> > > --- > > .../arm64/boot/dts/exynos/exynosautov920.dtsi | 40 > > +++++++++++++------ > > 1 file changed, 27 insertions(+), 13 deletions(-) > > > > diff --git a/arch/arm64/boot/dts/exynos/exynosautov920.dtsi > > b/arch/arm64/boot/dts/exynos/exynosautov920.dtsi > > index c1c8566d74f5..54fc32074379 100644 > > --- a/arch/arm64/boot/dts/exynos/exynosautov920.dtsi > > +++ b/arch/arm64/boot/dts/exynos/exynosautov920.dtsi > > > cut > > > @@ -224,7 +237,8 @@ serial_0: serial@10880000 { > > interrupts = <GIC_SPI 764 IRQ_TYPE_LEVEL_HIGH>; > > pinctrl-names = "default"; > > pinctrl-0 = <&uart0_bus>; > > - clocks = <&clock_usi>, <&clock_usi>; > > + clocks = <&cmu_peric0 CLK_MOUT_PERIC0_NOC_USER>, > > isn't this MUX common to multiple GATEs? Wouldn't turning it off affect > other users than the serial? > > Thanks, > ta > I don’t think there will be any problems you are worried about through the enable count of CCF. Thanks, Sunyeal Hong. > > + <&cmu_peric0 CLK_DOUT_PERIC0_USI00_USI>; > > clock-names = "uart", "clk_uart_baud0"; > > samsung,uart-fifosize = <256>; > > status = "disabled";