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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.
- clocks: Must contain an entry for each entry in clock-names.
  See ../clocks/clock-bindings.txt for details.
- clock-names: Must include the following entries:
  - mc: the module's clock input
- interrupts: The interrupt outputs from the controller.
- #iommu-cells: Should be 1. The single cell of the IOMMU specifier defines
  the SWGROUP of the master.

This device implements an IOMMU that complies with the generic IOMMU binding.
See ../iommu/iommu.txt for details.

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@70019000 {
		compatible = "nvidia,tegra124-mc";
		reg = <0x0 0x70019000 0x0 0x1000>;
		clocks = <&tegra_car TEGRA124_CLK_MC>;
		clock-names = "mc";

		interrupts = <GIC_SPI 77 IRQ_TYPE_LEVEL_HIGH>;

		#iommu-cells = <1>;
	};

	sdhci@700b0000 {
		compatible = "nvidia,tegra124-sdhci";
		...
		iommus = <&mc TEGRA_SWGROUP_SDMMC1A>;
	};
};

Example board file:

/ {
	memory-controller@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 */
				>;
			};
		};
	};
};