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| author | Tomeu Vizoso <tomeu.vizoso@collabora.com> | 2015-03-12 17:47:57 +0300 |
|---|---|---|
| committer | Thierry Reding <treding@nvidia.com> | 2015-05-05 12:10:17 +0300 |
| commit | 101197c39b459b6ab0045089b514f3ce8c0d8250 (patch) | |
| tree | 62b7d3bce5d5fbea836950012bc4a94ee69d5a1e /Documentation/devicetree/bindings/memory-controllers | |
| parent | d555a1a1286a55172a78f90b363d782846a5e629 (diff) | |
| download | linux-101197c39b459b6ab0045089b514f3ce8c0d8250.tar.xz | |
of: Document timings subnode of nvidia,tegra-mc
The MC driver needs some timing-specific information to program the EMEM
during a rate change of the EMC clock.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Diffstat (limited to 'Documentation/devicetree/bindings/memory-controllers')
| -rw-r--r-- | Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt | 84 |
1 files changed, 82 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt index f3db93c85eea..3338a2834ad7 100644 --- a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt +++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt @@ -1,6 +1,9 @@ NVIDIA Tegra Memory Controller device tree bindings =================================================== +memory-controller node +---------------------- + Required properties: - compatible: Should be "nvidia,tegra<chip>-mc" - reg: Physical base address and length of the controller's registers. @@ -15,9 +18,49 @@ Required properties: This device implements an IOMMU that complies with the generic IOMMU binding. See ../iommu/iommu.txt for details. -Example: --------- +emc-timings subnode +------------------- + +The node should contain a "emc-timings" subnode for each supported RAM type (see field RAM_CODE in +register PMC_STRAPPING_OPT_A). + +Required properties for "emc-timings" nodes : +- nvidia,ram-code : Should contain the value of RAM_CODE this timing set is used for. + +timing subnode +-------------- + +Each "emc-timings" node should contain a subnode for every supported EMC clock rate. + +Required properties for timing nodes : +- clock-frequency : Should contain the memory clock rate in Hz. +- nvidia,emem-configuration : Values to be written to the EMEM register block. For the Tegra124 SoC +(see section "15.6.1 MC Registers" in the TRM), these are the registers whose values need to be +specified, according to the board documentation: + + MC_EMEM_ARB_CFG + MC_EMEM_ARB_OUTSTANDING_REQ + MC_EMEM_ARB_TIMING_RCD + MC_EMEM_ARB_TIMING_RP + MC_EMEM_ARB_TIMING_RC + MC_EMEM_ARB_TIMING_RAS + MC_EMEM_ARB_TIMING_FAW + MC_EMEM_ARB_TIMING_RRD + MC_EMEM_ARB_TIMING_RAP2PRE + MC_EMEM_ARB_TIMING_WAP2PRE + MC_EMEM_ARB_TIMING_R2R + MC_EMEM_ARB_TIMING_W2W + MC_EMEM_ARB_TIMING_R2W + MC_EMEM_ARB_TIMING_W2R + MC_EMEM_ARB_DA_TURNS + MC_EMEM_ARB_DA_COVERS + MC_EMEM_ARB_MISC0 + MC_EMEM_ARB_MISC1 + MC_EMEM_ARB_RING1_THROTTLE +Example SoC include file: + +/ { mc: memory-controller@0,70019000 { compatible = "nvidia,tegra124-mc"; reg = <0x0 0x70019000 0x0 0x1000>; @@ -34,3 +77,40 @@ Example: ... iommus = <&mc TEGRA_SWGROUP_SDMMC1A>; }; +}; + +Example board file: + +/ { + memory-controller@0,70019000 { + emc-timings-3 { + nvidia,ram-code = <3>; + + timing-12750000 { + clock-frequency = <12750000>; + + nvidia,emem-configuration = < + 0x40040001 /* MC_EMEM_ARB_CFG */ + 0x8000000a /* MC_EMEM_ARB_OUTSTANDING_REQ */ + 0x00000001 /* MC_EMEM_ARB_TIMING_RCD */ + 0x00000001 /* MC_EMEM_ARB_TIMING_RP */ + 0x00000002 /* MC_EMEM_ARB_TIMING_RC */ + 0x00000000 /* MC_EMEM_ARB_TIMING_RAS */ + 0x00000002 /* MC_EMEM_ARB_TIMING_FAW */ + 0x00000001 /* MC_EMEM_ARB_TIMING_RRD */ + 0x00000002 /* MC_EMEM_ARB_TIMING_RAP2PRE */ + 0x00000008 /* MC_EMEM_ARB_TIMING_WAP2PRE */ + 0x00000003 /* MC_EMEM_ARB_TIMING_R2R */ + 0x00000002 /* MC_EMEM_ARB_TIMING_W2W */ + 0x00000003 /* MC_EMEM_ARB_TIMING_R2W */ + 0x00000006 /* MC_EMEM_ARB_TIMING_W2R */ + 0x06030203 /* MC_EMEM_ARB_DA_TURNS */ + 0x000a0402 /* MC_EMEM_ARB_DA_COVERS */ + 0x77e30303 /* MC_EMEM_ARB_MISC0 */ + 0x70000f03 /* MC_EMEM_ARB_MISC1 */ + 0x001f0000 /* MC_EMEM_ARB_RING1_THROTTLE */ + >; + }; + }; + }; +}; |