External Memory Controller can gather various hardware statistics that are intended to be used for debugging purposes and for dynamic frequency scaling of memory bus. Document the new mfd-simple compatible and EMC statistics sub-device. The subdev contains EMC DFS OPP table and interconnect paths to be used for dynamic scaling of system's memory bandwidth based on EMC utilization statistics. Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> --- .../memory-controllers/nvidia,tegra20-emc.txt | 43 +++++++++++++++++-- 1 file changed, 40 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.txt b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.txt index 8d09b228ac42..382aabcd6952 100644 --- a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.txt +++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.txt @@ -4,7 +4,7 @@ Properties: - name : Should be emc - #address-cells : Should be 1 - #size-cells : Should be 0 -- compatible : Should contain "nvidia,tegra20-emc". +- compatible : Should contain "nvidia,tegra20-emc" and "simple-mfd". - reg : Offset and length of the register set for the device - nvidia,use-ram-code : If present, the sub-nodes will be addressed and chosen using the ramcode board selector. If omitted, only one @@ -17,7 +17,8 @@ Properties: - core-supply: Phandle of voltage regulator of the SoC "core" power domain. - operating-points-v2: See ../bindings/opp/opp.txt for details. -Child device nodes describe the memory settings for different configurations and clock rates. +Child device nodes describe the memory settings for different configurations and clock rates, +as well as EMC activity statistics collection sub-device. Example: @@ -31,17 +32,34 @@ Example: ... }; + emc_bw_dfs_opp_table: emc_opp_table1 { + compatible = "operating-points-v2"; + + opp@36000000 { + opp-hz = /bits/ 64 <36000000>; + opp-peak-kBps = <144000>; + }; + ... + }; + memory-controller@7000f400 { #address-cells = < 1 >; #size-cells = < 0 >; #interconnect-cells = < 0 >; - compatible = "nvidia,tegra20-emc"; + compatible = "nvidia,tegra20-emc", "simple-mfd"; reg = <0x7000f400 0x400>; interrupts = <0 78 0x04>; clocks = <&tegra_car TEGRA20_CLK_EMC>; nvidia,memory-controller = <&mc>; core-supply = <&core_vdd_reg>; operating-points-v2 = <&emc_icc_dvfs_opp_table>; + + emc-stats { + compatible = "nvidia,tegra20-emc-statistics"; + operating-points-v2 = <&emc_bw_dfs_opp_table>; + interconnects = <&mc TEGRA20_MC_MPCORER &emc>; + interconnect-names = "cpu"; + }; } @@ -120,3 +138,22 @@ Properties: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >; }; + + + +Embedded Memory Controller statistics gathering sub-device + +EMC statistics subdev gathers information about hardware utilization +which is intended to be used for debugging purposes and for dynamic +frequency scaling based on the collected stats. + +Properties: +- name : Should be emc-stats. +- compatible : Should contain "nvidia,tegra20-emc-statistics". +- operating-points-v2: See ../bindings/opp/opp.txt for details. +- interconnects: Should contain entries for memory clients sitting on + MC->EMC memory interconnect path. +- interconnect-names: Should include name of the interconnect path for each + interconnect entry. Consult TRM documentation for + information about available memory clients, see MEMORY + CONTROLLER section. -- 2.27.0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel