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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt | |
parent | Initial commit. (diff) | |
download | linux-430c2fc249ea5c0536abd21c23382884005c9093.tar.xz linux-430c2fc249ea5c0536abd21c23382884005c9093.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt')
-rw-r--r-- | Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt new file mode 100644 index 000000000..02e4a1f86 --- /dev/null +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt @@ -0,0 +1,84 @@ +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device + +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM +memory chips are connected. The driver is to monitor the controller in runtime +and switch frequency and voltage. To monitor the usage of the controller in +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which +is able to measure the current load of the memory. +When 'userspace' governor is used for the driver, an application is able to +switch the DMC and memory frequency. + +Required properties for DMC device for Exynos5422: +- compatible: Should be "samsung,exynos5422-dmc". +- clocks : list of clock specifiers, must contain an entry for each + required entry in clock-names for CLK_FOUT_SPLL, CLK_MOUT_SCLK_SPLL, + CLK_FF_DOUT_SPLL2, CLK_FOUT_BPLL, CLK_MOUT_BPLL, CLK_SCLK_BPLL, + CLK_MOUT_MX_MSPLL_CCORE, CLK_MOUT_MX_MSPLL_CCORE_PHY, CLK_MOUT_MCLK_CDREX, +- clock-names : should include "fout_spll", "mout_sclk_spll", "ff_dout_spll2", + "fout_bpll", "mout_bpll", "sclk_bpll", "mout_mx_mspll_ccore", + "mout_mclk_cdrex" entries +- devfreq-events : phandles for PPMU devices connected to this DMC. +- vdd-supply : phandle for voltage regulator which is connected. +- reg : registers of two CDREX controllers. +- operating-points-v2 : phandle for OPPs described in v2 definition. +- device-handle : phandle of the connected DRAM memory device. For more + information please refer to documentation file: + Documentation/devicetree/bindings/ddr/lpddr3.txt +- devfreq-events : phandles of the PPMU events used by the controller. +- samsung,syscon-clk : phandle of the clock register set used by the controller, + these registers are used for enabling a 'pause' feature and are not + exposed by clock framework but they must be used in a safe way. + The register offsets are in the driver code and specyfic for this SoC + type. + +Optional properties for DMC device for Exynos5422: +- interrupt-parent : The parent interrupt controller. +- interrupts : Contains the IRQ line numbers for the DMC internal performance + event counters in DREX0 and DREX1 channels. Align with specification of the + interrupt line(s) in the interrupt-parent controller. +- interrupt-names : IRQ names "drex_0" and "drex_1", the order should be the + same as in the 'interrupts' list above. + +Example: + + ppmu_dmc0_0: ppmu@10d00000 { + compatible = "samsung,exynos-ppmu"; + reg = <0x10d00000 0x2000>; + clocks = <&clock CLK_PCLK_PPMU_DREX0_0>; + clock-names = "ppmu"; + events { + ppmu_event_dmc0_0: ppmu-event3-dmc0_0 { + event-name = "ppmu-event3-dmc0_0"; + }; + }; + }; + + dmc: memory-controller@10c20000 { + compatible = "samsung,exynos5422-dmc"; + reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>; + clocks = <&clock CLK_FOUT_SPLL>, + <&clock CLK_MOUT_SCLK_SPLL>, + <&clock CLK_FF_DOUT_SPLL2>, + <&clock CLK_FOUT_BPLL>, + <&clock CLK_MOUT_BPLL>, + <&clock CLK_SCLK_BPLL>, + <&clock CLK_MOUT_MX_MSPLL_CCORE>, + <&clock CLK_MOUT_MCLK_CDREX>; + clock-names = "fout_spll", + "mout_sclk_spll", + "ff_dout_spll2", + "fout_bpll", + "mout_bpll", + "sclk_bpll", + "mout_mx_mspll_ccore", + "mout_mclk_cdrex"; + operating-points-v2 = <&dmc_opp_table>; + devfreq-events = <&ppmu_event3_dmc0_0>, <&ppmu_event3_dmc0_1>, + <&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>; + device-handle = <&samsung_K3QF2F20DB>; + vdd-supply = <&buck1_reg>; + samsung,syscon-clk = <&clock>; + interrupt-parent = <&combiner>; + interrupts = <16 0>, <16 1>; + interrupt-names = "drex_0", "drex_1"; + }; |