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diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt deleted file mode 100644 index bcaa2c08ac11..000000000000 --- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt +++ /dev/null @@ -1,488 +0,0 @@ -* Generic Exynos Bus frequency device - -The Samsung Exynos SoC has many buses for data transfer between DRAM -and sub-blocks in SoC. Most Exynos SoCs share the common architecture -for buses. Generally, each bus of Exynos SoC includes a source clock -and a power line, which are able to change the clock frequency -of the bus in runtime. To monitor the usage of each bus in runtime, -the driver uses the PPMU (Platform Performance Monitoring Unit), which -is able to measure the current load of sub-blocks. - -The Exynos SoC includes the various sub-blocks which have the each AXI bus. -The each AXI bus has the owned source clock but, has not the only owned -power line. The power line might be shared among one more sub-blocks. -So, we can divide into two type of device as the role of each sub-block. -There are two type of bus devices as following: -- parent bus device -- passive bus device - -Basically, parent and passive bus device share the same power line. -The parent bus device can only change the voltage of shared power line -and the rest bus devices (passive bus device) depend on the decision of -the parent bus device. If there are three blocks which share the VDD_xxx -power line, Only one block should be parent device and then the rest blocks -should depend on the parent device as passive device. - - VDD_xxx |--- A block (parent) - |--- B block (passive) - |--- C block (passive) - -There are a little different composition among Exynos SoC because each Exynos -SoC has different sub-blocks. Therefore, such difference should be specified -in devicetree file instead of each device driver. In result, this driver -is able to support the bus frequency for all Exynos SoCs. - -Required properties for all bus devices: -- compatible: Should be "samsung,exynos-bus". -- clock-names : the name of clock used by the bus, "bus". -- clocks : phandles for clock specified in "clock-names" property. -- operating-points-v2: the OPP table including frequency/voltage information - to support DVFS (Dynamic Voltage/Frequency Scaling) feature. - -Required properties only for parent bus device: -- vdd-supply: the regulator to provide the buses with the voltage. -- devfreq-events: the devfreq-event device to monitor the current utilization - of buses. - -Required properties only for passive bus device: -- devfreq: the parent bus device. - -Optional properties only for parent bus device: -- exynos,saturation-ratio: the percentage value which is used to calibrate - the performance count against total cycle count. - -Optional properties for the interconnect functionality (QoS frequency -constraints): -- #interconnect-cells: should be 0. -- interconnects: as documented in ../interconnect.txt, describes a path at the - higher level interconnects used by this interconnect provider. - If this interconnect provider is directly linked to a top level interconnect - provider the property contains only one phandle. The provider extends - the interconnect graph by linking its node to a node registered by provider - pointed to by first phandle in the 'interconnects' property. - -- samsung,data-clock-ratio: ratio of the data throughput in B/s to minimum data - clock frequency in Hz, default value is 8 when this property is missing. - -Detailed correlation between sub-blocks and power line according to Exynos SoC: -- In case of Exynos3250, there are two power line as following: - VDD_MIF |--- DMC - - VDD_INT |--- LEFTBUS (parent device) - |--- PERIL - |--- MFC - |--- G3D - |--- RIGHTBUS - |--- PERIR - |--- FSYS - |--- LCD0 - |--- PERIR - |--- ISP - |--- CAM - -- In case of Exynos4210, there is one power line as following: - VDD_INT |--- DMC (parent device) - |--- LEFTBUS - |--- PERIL - |--- MFC(L) - |--- G3D - |--- TV - |--- LCD0 - |--- RIGHTBUS - |--- PERIR - |--- MFC(R) - |--- CAM - |--- FSYS - |--- GPS - |--- LCD0 - |--- LCD1 - -- In case of Exynos4x12, there are two power line as following: - VDD_MIF |--- DMC - - VDD_INT |--- LEFTBUS (parent device) - |--- PERIL - |--- MFC(L) - |--- G3D - |--- TV - |--- IMAGE - |--- RIGHTBUS - |--- PERIR - |--- MFC(R) - |--- CAM - |--- FSYS - |--- GPS - |--- LCD0 - |--- ISP - -- In case of Exynos5422, there are two power line as following: - VDD_MIF |--- DREX 0 (parent device, DRAM EXpress controller) - |--- DREX 1 - - VDD_INT |--- NoC_Core (parent device) - |--- G2D - |--- G3D - |--- DISP1 - |--- NoC_WCORE - |--- GSCL - |--- MSCL - |--- ISP - |--- MFC - |--- GEN - |--- PERIS - |--- PERIC - |--- FSYS - |--- FSYS2 - -- In case of Exynos5433, there is VDD_INT power line as following: - VDD_INT |--- G2D (parent device) - |--- MSCL - |--- GSCL - |--- JPEG - |--- MFC - |--- HEVC - |--- BUS0 - |--- BUS1 - |--- BUS2 - |--- PERIS (Fixed clock rate) - |--- PERIC (Fixed clock rate) - |--- FSYS (Fixed clock rate) - -Example 1: - Show the AXI buses of Exynos3250 SoC. Exynos3250 divides the buses to - power line (regulator). The MIF (Memory Interface) AXI bus is used to - transfer data between DRAM and CPU and uses the VDD_MIF regulator. - - - MIF (Memory Interface) block - : VDD_MIF |--- DMC (Dynamic Memory Controller) - - - INT (Internal) block - : VDD_INT |--- LEFTBUS (parent device) - |--- PERIL - |--- MFC - |--- G3D - |--- RIGHTBUS - |--- FSYS - |--- LCD0 - |--- PERIR - |--- ISP - |--- CAM - - - MIF bus's frequency/voltage table - ----------------------- - |Lv| Freq | Voltage | - ----------------------- - |L1| 50000 |800000 | - |L2| 100000 |800000 | - |L3| 134000 |800000 | - |L4| 200000 |825000 | - |L5| 400000 |875000 | - ----------------------- - - - INT bus's frequency/voltage table - ---------------------------------------------------------- - |Block|LEFTBUS|RIGHTBUS|MCUISP |ISP |PERIL ||VDD_INT | - | name| |LCD0 | | | || | - | | |FSYS | | | || | - | | |MFC | | | || | - ---------------------------------------------------------- - |Mode |*parent|passive |passive|passive|passive|| | - ---------------------------------------------------------- - |Lv |Frequency ||Voltage | - ---------------------------------------------------------- - |L1 |50000 |50000 |50000 |50000 |50000 ||900000 | - |L2 |80000 |80000 |80000 |80000 |80000 ||900000 | - |L3 |100000 |100000 |100000 |100000 |100000 ||1000000 | - |L4 |134000 |134000 |200000 |200000 | ||1000000 | - |L5 |200000 |200000 |400000 |300000 | ||1000000 | - ---------------------------------------------------------- - -Example 2: - The bus of DMC (Dynamic Memory Controller) block in exynos3250.dtsi - is listed below: - - bus_dmc: bus_dmc { - compatible = "samsung,exynos-bus"; - clocks = <&cmu_dmc CLK_DIV_DMC>; - clock-names = "bus"; - operating-points-v2 = <&bus_dmc_opp_table>; - status = "disabled"; - }; - - bus_dmc_opp_table: opp_table1 { - compatible = "operating-points-v2"; - opp-shared; - - opp-50000000 { - opp-hz = /bits/ 64 <50000000>; - opp-microvolt = <800000>; - }; - opp-100000000 { - opp-hz = /bits/ 64 <100000000>; - opp-microvolt = <800000>; - }; - opp-134000000 { - opp-hz = /bits/ 64 <134000000>; - opp-microvolt = <800000>; - }; - opp-200000000 { - opp-hz = /bits/ 64 <200000000>; - opp-microvolt = <825000>; - }; - opp-400000000 { - opp-hz = /bits/ 64 <400000000>; - opp-microvolt = <875000>; - }; - }; - - bus_leftbus: bus_leftbus { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_GDL>; - clock-names = "bus"; - operating-points-v2 = <&bus_leftbus_opp_table>; - status = "disabled"; - }; - - bus_rightbus: bus_rightbus { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_GDR>; - clock-names = "bus"; - operating-points-v2 = <&bus_leftbus_opp_table>; - status = "disabled"; - }; - - bus_lcd0: bus_lcd0 { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_ACLK_160>; - clock-names = "bus"; - operating-points-v2 = <&bus_leftbus_opp_table>; - status = "disabled"; - }; - - bus_fsys: bus_fsys { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_ACLK_200>; - clock-names = "bus"; - operating-points-v2 = <&bus_leftbus_opp_table>; - status = "disabled"; - }; - - bus_mcuisp: bus_mcuisp { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_ACLK_400_MCUISP>; - clock-names = "bus"; - operating-points-v2 = <&bus_mcuisp_opp_table>; - status = "disabled"; - }; - - bus_isp: bus_isp { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_ACLK_266>; - clock-names = "bus"; - operating-points-v2 = <&bus_isp_opp_table>; - status = "disabled"; - }; - - bus_peril: bus_peril { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_DIV_ACLK_100>; - clock-names = "bus"; - operating-points-v2 = <&bus_peril_opp_table>; - status = "disabled"; - }; - - bus_mfc: bus_mfc { - compatible = "samsung,exynos-bus"; - clocks = <&cmu CLK_SCLK_MFC>; - clock-names = "bus"; - operating-points-v2 = <&bus_leftbus_opp_table>; - status = "disabled"; - }; - - bus_leftbus_opp_table: opp_table1 { - compatible = "operating-points-v2"; - opp-shared; - - opp-50000000 { - opp-hz = /bits/ 64 <50000000>; - opp-microvolt = <900000>; - }; - opp-80000000 { - opp-hz = /bits/ 64 <80000000>; - opp-microvolt = <900000>; - }; - opp-100000000 { - opp-hz = /bits/ 64 <100000000>; - opp-microvolt = <1000000>; - }; - opp-134000000 { - opp-hz = /bits/ 64 <134000000>; - opp-microvolt = <1000000>; - }; - opp-200000000 { - opp-hz = /bits/ 64 <200000000>; - opp-microvolt = <1000000>; - }; - }; - - bus_mcuisp_opp_table: opp_table2 { - compatible = "operating-points-v2"; - opp-shared; - - opp-50000000 { - opp-hz = /bits/ 64 <50000000>; - }; - opp-80000000 { - opp-hz = /bits/ 64 <80000000>; - }; - opp-100000000 { - opp-hz = /bits/ 64 <100000000>; - }; - opp-200000000 { - opp-hz = /bits/ 64 <200000000>; - }; - opp-400000000 { - opp-hz = /bits/ 64 <400000000>; - }; - }; - - bus_isp_opp_table: opp_table3 { - compatible = "operating-points-v2"; - opp-shared; - - opp-50000000 { - opp-hz = /bits/ 64 <50000000>; - }; - opp-80000000 { - opp-hz = /bits/ 64 <80000000>; - }; - opp-100000000 { - opp-hz = /bits/ 64 <100000000>; - }; - opp-200000000 { - opp-hz = /bits/ 64 <200000000>; - }; - opp-300000000 { - opp-hz = /bits/ 64 <300000000>; - }; - }; - - bus_peril_opp_table: opp_table4 { - compatible = "operating-points-v2"; - opp-shared; - - opp-50000000 { - opp-hz = /bits/ 64 <50000000>; - }; - opp-80000000 { - opp-hz = /bits/ 64 <80000000>; - }; - opp-100000000 { - opp-hz = /bits/ 64 <100000000>; - }; - }; - - - Usage case to handle the frequency and voltage of bus on runtime - in exynos3250-rinato.dts is listed below: - - &bus_dmc { - devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>; - vdd-supply = <&buck1_reg>; /* VDD_MIF */ - status = "okay"; - }; - - &bus_leftbus { - devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>; - vdd-supply = <&buck3_reg>; - status = "okay"; - }; - - &bus_rightbus { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - - &bus_lcd0 { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - - &bus_fsys { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - - &bus_mcuisp { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - - &bus_isp { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - - &bus_peril { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - - &bus_mfc { - devfreq = <&bus_leftbus>; - status = "okay"; - }; - -Example 3: - An interconnect path "bus_display -- bus_leftbus -- bus_dmc" on - Exynos4412 SoC with video mixer as an interconnect consumer device. - - soc { - bus_dmc: bus_dmc { - compatible = "samsung,exynos-bus"; - clocks = <&clock CLK_DIV_DMC>; - clock-names = "bus"; - operating-points-v2 = <&bus_dmc_opp_table>; - samsung,data-clock-ratio = <4>; - #interconnect-cells = <0>; - }; - - bus_leftbus: bus_leftbus { - compatible = "samsung,exynos-bus"; - clocks = <&clock CLK_DIV_GDL>; - clock-names = "bus"; - operating-points-v2 = <&bus_leftbus_opp_table>; - #interconnect-cells = <0>; - interconnects = <&bus_dmc>; - }; - - bus_display: bus_display { - compatible = "samsung,exynos-bus"; - clocks = <&clock CLK_ACLK160>; - clock-names = "bus"; - operating-points-v2 = <&bus_display_opp_table>; - #interconnect-cells = <0>; - interconnects = <&bus_leftbus &bus_dmc>; - }; - - bus_dmc_opp_table: opp_table1 { - compatible = "operating-points-v2"; - /* ... */ - } - - bus_leftbus_opp_table: opp_table3 { - compatible = "operating-points-v2"; - /* ... */ - }; - - bus_display_opp_table: opp_table4 { - compatible = "operating-points-v2"; - /* .. */ - }; - - &mixer { - compatible = "samsung,exynos4212-mixer"; - interconnects = <&bus_display &bus_dmc>; - /* ... */ - }; - }; |