Re: [PATCH v6 08/52] dt-bindings: memory: tegra20: emc: Document mfd-simple compatible and statistics sub-device

Krzysztof Kozlowski
2020-10-27T09:02:22Z

On Mon, Oct 26, 2020 at 01:16:51AM +0300, Dmitry Osipenko wrote:
> 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@gmail.com>
> ---
> .../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".

Changing a compatible match is another break of ABI, unless it is not
really required. It's unclear to me from the contents of the patch.

> - 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 {

Hyphens for node name.

Best regards,
Krzysztof