Re: [PATCH 3/5] Documentation: bindings: add dt documentation for rk3399 dmc
From: Chanwoo Choi
Date: Fri Sep 02 2016 - 04:54:21 EST
On 2016ë 09ì 02ì 07:31, Lin Huang wrote:
> This patch adds the documentation for rockchip rk3399 dmc driver.
>
> Signed-off-by: Lin Huang <hl@xxxxxxxxxxxxxx>
> ---
> Changes in v8:
> - add ddr timing properties
>
> Changes in v7:
> -None
>
> Changes in v6:
> -Add more detail in Documentation
>
> Changes in v5:
> -None
>
> Changes in v4:
> -None
>
> Changes in v3:
> -None
>
> Changes in v2:
> -None
>
> Changes in v1:
> -None
>
> .../devicetree/bindings/devfreq/rk3399_dmc.txt | 173 +++++++++++++++++++++
> 1 file changed, 173 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt
>
> diff --git a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt
> new file mode 100644
> index 0000000..1f39b5cb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt
> @@ -0,0 +1,173 @@
> +* Rockchip rk3399 DMC(Dynamic Memory Controller) device
> +
> +Required properties:
> +- compatible: Must be "rockchip,rk3399-dmc".
> +- devfreq-events: Node to get DDR loading, Refer to
> + Documentation/devicetree/bindings/devfreq/
> + rockchip-dfi.txt
> +- interrupts: The interrupt number to the CPU. The interrupt
> + specifier format depends on the interrupt controller.
> + It should be DCF interrupts, when DDR dvfs finish,
> + it will happen.
> +- clocks: Phandles for clock specified in "clock-names" property
> +- clock-names : The name of clock used by the DFI, must be
> + "pclk_ddr_mon";
> +- operating-points-v2: Refer to Documentation/devicetree/bindings/power/opp.txt
> + for details.
> +- center-supply: DMC supply node.
> +- status: Marks the node enabled/disabled.
> +
> +Following properties are ddr timing:
> +
> +- dram_speed_bin : Value is defined at include/dt-bindings/clock/ddr.h,
> + it select ddr3 cl-trp-trcd type, default value
> + "DDR3_DEFAULT".it must selected according to
> + "Speed Bin" in ddr3 datasheet, DO NOT use smaller
> + "Speed Bin" than ddr3 exactly is.
> +
> +- pd_idle : Config the PD_IDLE value, defined the power-down idle
> + period, memories are places into power-down mode if
> + bus is idle for PD_IDLE DFI clocks.
> +
> +- sr_idle : Configure the SR_IDLE value, defined the selfrefresh
> + idle period, memories are places into self-refresh
> + mode if bus is idle for SR_IDLE*1024 DFI clocks
> + (DFI clocks freq is half of dram's clocks), defaule
> + value is "0".
> +
> +- sr_mc_gate_idle : Defined the self-refresh with memory and controller
> + clock gating idle period, memories are places into
> + self-refresh mode and memory controller clock arg
> + gating if bus is idle for sr_mc_gate_idle*1024 DFI
> + clocks.
> +
> +- srpd_lite_idle : Defined the self-refresh power down idle period,
> + memories are places into self-refresh power down
> + mode if bus is idle for srpd_lite_idle*1024 DFI
> + clocks. This parameter is for LPDDR4 only.
> +
> +- standby_idle : Defined the standby idle period, memories are places
> + into self-refresh than controller, pi, phy and dram
> + clock will gating if bus is idle for
> + standby_idle * DFI clocks.
> +
> +- dram_dll_disb_freq : It's defined the DDR3 dll bypass frequency in MHz
> + when ddr freq less than DRAM_DLL_DISB_FREQ, ddr3
> + dll will bypssed note: if dll was bypassed, the
> + odt also stop working.
> +
> +- phy_dll_disb_freq : Defined the PHY dll bypass frequency in MHz (Mega Hz),
> + when ddr freq less than DRAM_DLL_DISB_FREQ, phy dll
> + will bypssed. note: phy dll and phy odt are
> + independent
> +
> +- ddr3_odt_disb_freq : When dram type is DDR3, this parameter defined the
> + odt disable frequency in MHz (Mega Hz), when ddr
> + frequency less then ddr3_odt_disb_freq, the odt
> + on dram side and controller side are both disabled.
> +
> +- ddr3_drv : When dram type is DDR3, this parameter define the
> + dram side driver stength in ohm, default value is
> + DDR3_DS_40ohm.
> +
> +- ddr3_odt : When dram type is DDR3, this parameter define the
> + dram side ODT stength in ohm, default value is
> + DDR3_ODT_120ohm.
> +
> +- phy_ddr3_ca_drv : When dram type is DDR3, this parameter define the phy
> + side CA line(incluing command line, address line and
> + clock line) driver strength. default value is
> + PHY_DRV_ODT_40.
> +
> +- phy_ddr3_dq_drv : When dram type is DDR3, this parameter define the phy
> + side DQ line(incluing DQS/DQ/DM line) driver strength.
> + default value is PHY_DRV_ODT_40.
> +
> +- phy_ddr3_odt : When dram type is DDR3, this parameter define the
> + phy side odt strength, default value is
> + PHY_DRV_ODT_240.
> +
> +- lpddr3_odt_disb_freq : When dram type is LPDDR3, this parameter defined then
> + odt disable frequency in MHz (Mega Hz), when ddr
> + frequency less then ddr3_odt_disb_freq, the odt on
> + dram side and controller side are both disabled.
> +
> +- lpddr3_drv : When dram type is LPDDR3, this parameter define the
> + dram side driver stength in ohm, default value is
> + LP3_DS_34ohm.
> +
> +- lpddr3_odt : When dram type is LPDDR3, this parameter define the
> + dram side ODT stength in ohm, default value is
> + LP3_ODT_240ohm.
> +
> +- phy_lpddr3_ca_drv : When dram type is LPDDR3, this parameter define the
> + phy side CA line(incluing command line, address line
> + and clock line) driver strength. default value is
> + PHY_DRV_ODT_40.
> +
> +- phy_lpddr3_dq_drv : When dram type is LPDDR3, this parameter define the
> + phy side DQ line(incluing DQS/DQ/DM line) driver
> + strength. default value is PHY_DRV_ODT_40.
> +
> +- phy_lpddr3_odt : When dram type is LPDDR3, this parameter define the phy
> + side odt strength, default value is PHY_DRV_ODT_240.
> +
> +- lpddr4_odt_disb_freq : When dram type is LPDDR4, this parameter defined the
> + odt disable frequency in MHz (Mega Hz), when ddr
> + frequency less then ddr3_odt_disb_freq, the odt on
> + dram side and controller side are both disabled.
> +
> +- lpddr4_drv : When dram type is LPDDR4, this parameter define the
> + dram side driver stength in ohm, default value is
> + LP4_PDDS_60ohm.
> +
> +- lpddr4_dq_odt : When dram type is LPDDR4, this parameter define the
> + dram side ODT on dqs/dq line stength in ohm, default
> + value is LP4_DQ_ODT_40ohm.
> +
> +- lpddr4_ca_odt : When dram type is LPDDR4, this parameter define the
> + dram side ODT on ca line stength in ohm, default value
> + is LP4_CA_ODT_40ohm.
> +
> +- phy_lpddr4_ca_drv : When dram type is LPDDR4, this parameter define the
> + phy side CA line(incluing command address line)
> + driver strength. default value is PHY_DRV_ODT_40.
> +
> +- phy_lpddr4_ck_cs_drv : When dram type is LPDDR4, this parameter define the
> + phy side clock line and cs line driver strength.
> + default value is PHY_DRV_ODT_80.
> +
> +- phy_lpddr4_dq_drv : When dram type is LPDDR4, this parameter define the
> + phy side DQ line(incluing DQS/DQ/DM line) driver
> + strength. default value is PHY_DRV_ODT_80.
> +
> +- phy_lpddr4_odt : When dram type is LPDDR4, this parameter define the
> + phy side odt strength, default value is PHY_DRV_ODT_60.
It is good to explain the each field for ddr timing.
But, why you you drop the example for ddr timing values?
I think that you better to add the example for ddr timing values
> +
> +Example:
> + dmc_opp_table: dmc_opp_table {
> + compatible = "operating-points-v2";
> +
> + opp00 {
> + opp-hz = /bits/ 64 <300000000>;
> + opp-microvolt = <900000>;
> + };
> + opp01 {
> + opp-hz = /bits/ 64 <666000000>;
> + opp-microvolt = <900000>;
> + };
> + };
> +
> + dmc: dmc {
> + compatible = "rockchip,rk3399-dmc";
> + devfreq-events = <&dfi>;
> + interrupts = <GIC_SPI 1 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&cru SCLK_DDRCLK>;
> + clock-names = "dmc_clk";
> + operating-points-v2 = <&dmc_opp_table>;
> + center-supply = <&ppvar_centerlogic>;
> + upthreshold = <15>;
> + downdifferential = <10>;
> + status = "disabled";
> + };
> +
>
--
Best Regards,
Chanwoo Choi