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@xxxxxxxxxxxxx>
---
.../memory-controllers/nvidia,tegra-mc.txt | 46 +++++++++++++++++++++-
1 file changed, 44 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 f3db93c..8467b8c 100644
--- a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt
+++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra-mc.txt
@@ -15,9 +15,26 @@ Required properties:
This device implements an IOMMU that complies with the generic IOMMU binding.
See ../iommu/iommu.txt for details.
-Example:
---------
+The node should contain a "timings" subnode for each supported RAM type (see
+field RAM_CODE in register PMC_STRAPPING_OPT_A), with its unit address being its
+RAM_CODE.
+Required properties for "timings" nodes :
+- nvidia,ram-code : Should contain the value of RAM_CODE this timing set is used
+for.
+
+Each "timings" node should contain a "timing" subnode for every supported EMC
+clock rate. The "timing" subnodes should have the clock rate in Hz as their unit
+address.
+
+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,
+as specified by the board documentation.
+
+Example SoC include file:
+
+/ {
mc: memory-controller@0,70019000 {
compatible = "nvidia,tegra124-mc";
reg = <0x0 0x70019000 0x0 0x1000>;
@@ -34,3 +51,28 @@ Example:
...
iommus = <&mc TEGRA_SWGROUP_SDMMC1A>;
};
+};
+
+Example board file:
+
+/ {
+ memory-controller@0,70019000 {
+ 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 */
+ >;
+ };
+ };
+ };
+};
--
1.9.3
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