Re: [PATCH] arm64: dts: imx8mp: Improve VPU clock configuration

[Marco Felsch <m.felsch@pengutronix.de>]

Hi Marek,

On 23-08-10, Marek Vasut wrote:
> Update VPU clock according to reference manual to improve performance.
> i.MX 8M Plus Applications Processor Reference Manual, Rev. 1, 06/2021
> 
> Table 5-1. Clock Root Table (continued) reads as follows:
> Clock Root ............... Max Freq (MHz)
> VPU_BUS_CLK_ROOT ......... 800
> VPU_G1_CLK_ROOT .......... 800
> VPU_G2_CLK_ROOT .......... 700
> 
> 5.1.5.1 Input Clocks
> Input Clock .............. Frequency (MHz)
> VPU_PLL_CLK .............. 800

Acoording the datasheet not the reference manual, this would be the
overdrive mode now. Can we ensure that VDD_SOC is in overdrive state?

Regards,
  Marco

> The VPU G1 and VPU bus is now supplied from PLL1 which provides 800 MHz
> on one of its outputs, the VPU G2 is supplied from VPU PLL with 700 MHz
> which is a perfect fit for this setup. This also matches the NXP kernel
> fork configuration.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> ---
> Cc: Adam Ford <aford173@gmail.com>
> Cc: Alexander Stein <alexander.stein@ew.tq-group.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Fabio Estevam <festevam@gmail.com>
> Cc: Frank Li <Frank.Li@nxp.com>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Marek Vasut <marex@denx.de>
> Cc: NXP Linux Team <linux-imx@nxp.com>
> Cc: Peng Fan <peng.fan@nxp.com>
> Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
> Cc: Richard Cochran <richardcochran@gmail.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Sascha Hauer <s.hauer@pengutronix.de>
> Cc: Shawn Guo <shawnguo@kernel.org>
> Cc: devicetree@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index 6f2f50e1639c3..77974bd6da63a 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> @@ -1928,8 +1928,8 @@ vpu_g1: video-codec@38300000 {
>  			interrupts = <GIC_SPI 7 IRQ_TYPE_LEVEL_HIGH>;
>  			clocks = <&clk IMX8MP_CLK_VPU_G1_ROOT>;
>  			assigned-clocks = <&clk IMX8MP_CLK_VPU_G1>;
> -			assigned-clock-parents = <&clk IMX8MP_VPU_PLL_OUT>;
> -			assigned-clock-rates = <600000000>;
> +			assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_800M>;
> +			assigned-clock-rates = <800000000>;
>  			power-domains = <&vpumix_blk_ctrl IMX8MP_VPUBLK_PD_G1>;
>  		};
>  
> @@ -1939,8 +1939,8 @@ vpu_g2: video-codec@38310000 {
>  			interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
>  			clocks = <&clk IMX8MP_CLK_VPU_G2_ROOT>;
>  			assigned-clocks = <&clk IMX8MP_CLK_VPU_G2>;
> -			assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_1000M>;
> -			assigned-clock-rates = <500000000>;
> +			assigned-clock-parents = <&clk IMX8MP_VPU_PLL_OUT>;
> +			assigned-clock-rates = <700000000>;
>  			power-domains = <&vpumix_blk_ctrl IMX8MP_VPUBLK_PD_G2>;
>  		};
>  
> @@ -1956,8 +1956,8 @@ vpumix_blk_ctrl: blk-ctrl@38330000 {
>  				 <&clk IMX8MP_CLK_VPU_VC8KE_ROOT>;
>  			clock-names = "g1", "g2", "vc8000e";
>  			assigned-clocks = <&clk IMX8MP_CLK_VPU_BUS>, <&clk IMX8MP_VPU_PLL>;
> -			assigned-clock-parents = <&clk IMX8MP_VPU_PLL_OUT>;
> -			assigned-clock-rates = <600000000>, <600000000>;
> +			assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_800M>;
> +			assigned-clock-rates = <800000000>, <700000000>;
>  			interconnects = <&noc IMX8MP_ICM_VPU_G1 &noc IMX8MP_ICN_VIDEO>,
>  					<&noc IMX8MP_ICM_VPU_G2 &noc IMX8MP_ICN_VIDEO>,
>  					<&noc IMX8MP_ICM_VPU_H1 &noc IMX8MP_ICN_VIDEO>;
> -- 
> 2.40.1
> 
> 
>