Re: [PATCH v2 13/19] ARM: dts: Add bus nodes using VDD_MIF for Exynos4x12

From: Krzysztof Kozlowski
Date: Wed Dec 09 2015 - 22:17:44 EST


On 09.12.2015 13:08, Chanwoo Choi wrote:
> This patch adds the bus noes using VDD_MIF for Exynos4x12 SoC.

s/noes/nodes/

> Exynos4x12 has the following AXI buses to translate data
> between DRAM and DMC/ACP/C2C.
>
> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> ---
> arch/arm/boot/dts/exynos4x12.dtsi | 72 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 72 insertions(+)
>
> diff --git a/arch/arm/boot/dts/exynos4x12.dtsi b/arch/arm/boot/dts/exynos4x12.dtsi
> index b77dac61ffb5..3bcf0939755e 100644
> --- a/arch/arm/boot/dts/exynos4x12.dtsi
> +++ b/arch/arm/boot/dts/exynos4x12.dtsi
> @@ -282,6 +282,78 @@
> clocks = <&clock CLK_SMMU_LITE1>, <&clock CLK_FIMC_LITE1>;
> #iommu-cells = <0>;
> };
> +
> + bus_dmc: bus_dmc {
> + compatible = "samsung,exynos-bus";
> + clocks = <&clock CLK_DIV_DMC>;
> + clock-names = "bus";
> + operating-points-v2 = <&bus_dmc_opp_table>;
> + status = "disabled";
> + };
> +
> + bus_acp: bus_acp {
> + compatible = "samsung,exynos-bus";
> + clocks = <&clock CLK_DIV_ACP>;
> + clock-names = "bus";
> + operating-points-v2 = <&bus_acp_opp_table>;
> + status = "disabled";
> + };
> +
> + bus_c2c: bus_c2c {
> + compatible = "samsung,exynos-bus";
> + clocks = <&clock CLK_DIV_C2C>;
> + clock-names = "bus";
> + operating-points-v2 = <&bus_dmc_opp_table>;
> + status = "disabled";
> + };
> +
> + bus_dmc_opp_table: opp_table1 {
> + compatible = "operating-points-v2";
> + opp-shared;
> +
> + opp00 {
> + opp-hz = /bits/ 64 <100000000>;
> + opp-microvolt = <900000>;
> + };
> + opp01 {
> + opp-hz = /bits/ 64 <134000000>;
> + opp-microvolt = <900000>;
> + };
> + opp02 {
> + opp-hz = /bits/ 64 <160000000>;
> + opp-microvolt = <900000>;
> + };
> + opp03 {
> + opp-hz = /bits/ 64 <200000000>;
> + opp-microvolt = <950000>;

The exyno4_bus.c (from mainline) uses 267 MHz here. Why choosing 200 MHz?

Best regards,
Krzysztof

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/