[PATCH net-next v4 1/2] dt-bindings: net: cdns,macb: Add rx-watermark property

From: Pranavi Somisetty
Date: Tue Jun 13 2023 - 01:44:03 EST


watermark value is the minimum amount of packet data
required to activate the forwarding process. The watermark
implementation and maximum size is dependent on the device
where Cadence MACB/GEM is used.

Signed-off-by: Pranavi Somisetty <pranavi.somisetty@xxxxxxx>
---
Changes v2:
None (patch added in v2)

Changes v3:
1. Fixed DT schema error: "scalar properties shouldn't have array keywords".
2. Modified description of rx-watermark to include units of the watermark value.
3. Modified the DT property name corresponding to rx_watermark in
pbuf_rxcutthru to "cdns,rx-watermark".
4. Modified commit description to remove references to Xilinx platforms,
since the changes aren't platform specific.

Changes v4:
1. Modified description for "rx-watermark" property in the DT bindings.
2. Changed the width of the rx-watermark property to uint32.
---
Documentation/devicetree/bindings/net/cdns,macb.yaml | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/cdns,macb.yaml b/Documentation/devicetree/bindings/net/cdns,macb.yaml
index bef5e0f895be..bf8894a0257e 100644
--- a/Documentation/devicetree/bindings/net/cdns,macb.yaml
+++ b/Documentation/devicetree/bindings/net/cdns,macb.yaml
@@ -109,6 +109,16 @@ properties:
power-domains:
maxItems: 1

+ cdns,rx-watermark:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ When the receive partial store and forward mode is activated,
+ the receiver will only begin to forward the packet to the external
+ AHB or AXI slave when enough packet data is stored in the SRAM packet buffer.
+ rx-watermark corresponds to the number of SRAM buffer locations,
+ that need to be filled, before the forwarding process is activated.
+ Width of the SRAM is platform dependent, and can be 4, 8 or 16 bytes.
+
'#address-cells':
const: 1

@@ -166,6 +176,7 @@ examples:
compatible = "cdns,macb";
reg = <0xfffc4000 0x4000>;
interrupts = <21>;
+ cdns,rx-watermark = <0x44>;
phy-mode = "rmii";
local-mac-address = [3a 0e 03 04 05 06];
clock-names = "pclk", "hclk", "tx_clk";
--
2.36.1