[PATCH v4 2/4] Documentation: Add APM X-Gene SoC 15Gbps Multi-purpose PHY driver binding documentation

[Loc Ho <lho@apm.com>]

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
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 .../devicetree/bindings/ata/apm-xgene-phy.txt      |   89 ++++++++++++++++++++
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+* APM X-Gene 15Gbps Multi-purpose PHY nodes
+
+PHY nodes are defined to describe on-chip 15Gbps Multi-purpose PHY. Each
+PHY (pair of lanes) has its own node.
+
+Required properties:
+- compatible		: Shall be "apm,xgene-phy" or
+			  "apm,xgene-phy-ext". The "apm,xgene-phy" describes
+			  an PHY with internal reference PLL located within
+			  the IP. The "apm,xgene-phy-ext" describes an PHY
+			  where the internal reference PLL located outside of
+			  the IP.
+- reg			: First PHY memory resource is the SDS PHY access
+			  resource.
+			  Second PHY memory resoruce is the clock and reset
+			  resources.
+			  Third PHY memory resource is the SDS PHY access
+			  resource outside of the IP if it is type
+			  "apm,xgene-phy-ext".
+- #phy-cells		: Shall be 1 as it expects one argument for setting
+			  the mode of the PHY. Possible values are 0 (SATA),
+			  1 (SGMII), 2 (PCIe), or 3 (USB).
+
+Optional properties:
+- status		: Shall be "ok" if enabled or "disabled" if disabled.
+			  Default is "ok".
+- apm,tx-eye-tuning	: Manual control to fine tune the capture of the serial
+			  bit lines from the automatic calibrated position.
+			  Two set of 3-tuple setting for Gen1, Gen2, and Gen3.
+			  Range from 0 to 0x7f in unit of one bit period.
+			  Default is 0xa.
+- apm,tx-eye-direction	: Eye tuning manual control direction. 0 means sample
+			  data earlier than the nominal sampling point. 1 means
+			  sample data later than the nominal sampling point.
+			  Two set of 3-tuple setting for Gen1, Gen2, and Gen3.
+			  Default is 0x0.
+- apm,tx-boost-gain	: Frequency boost AC (LSB 3-bit) and DC (2-bit)
+			  gain control. Two set of 3-tuple setting for Gen1,
+			  Gen2, and Gen3. Range is between 0 to 0x1f in unit
+			  of dB. Default is 0x3.
+- apm,tx-amplitude	: Amplitude control. Two set of 3-tuple setting for
+			  Gen1, Gen2, and Gen3. Range is between 0 to 0xf in
+			  unit of 13.3mV. Default is 0xf.
+- apm,tx-pre-cursor1	: 1st pre-cursor emphasis taps control. Two set of
+			  3-tuple setting for Gen1, Gen2, and Gen3. Range is
+			  between 0 to 0xf in unit of 18.2mV. Default is 0x0.
+- apm,tx-pre-cursor2	: 2st pre-cursor emphasis taps control. Two set of
+			  3-tuple setting for Gen1, Gen2, and Gen3. Range is
+			  between 0 to 0x7 in unit of 18.2mV. Default is 0x0.
+- apm,tx-post-cursor	: Post-cursor emphasis taps control. Two set of
+			  3-tuple setting for Gen1, Gen2, and Gen3. Range is
+			  between 0 to 0x1f in unit of 18.2mV. Default is 0xf.
+- apm,tx-speed		: Tx operating speed. One set of 3-tuple for
+			  Gen1 (0x1), Gen2 (0x3), and Gen3 (0x7). Default is
+			  0x7.
+
+NOTE: PHY override parameters are board specific setting.
+
+Example:
+		phy1: phy@1f21a000 {
+			compatible = "apm,xgene-phy";
+			reg = <0x0 0x1f21a000 0x0 0x100>,
+			      <0x0 0x1f21c000 0x0 0x100>;
+			#phy-cells = <1>;
+			status = "disabled";
+			apm,tx-boost-gain = <0x2 0x2 0x2 0x2 0x2 0x2>;
+			apm,tx-eye-tuning = <0xa 0xa 0xa 0xa 0xa 0xa>;
+		};
+
+		phy2: phy@1f22a000 {
+			compatible = "apm,xgene-phy";
+			reg = <0x0 0x1f22a000 0x0 0x100>,
+			      <0x0 0x1f22c000 0x0 0x100>;
+			#phy-cells = <1>;
+			status = "ok";
+			apm,tx-boost-gain = <0x2 0x2 0x2 0x2 0x2 0x2>;
+			apm,tx-eye-tuning = <0xa 0xa 0xa 0x5 0x5 0x5>;
+		};
+
+		phy3: phy@1f23a000 {
+			compatible = "apm,xgene-phy-ext";
+			reg = <0x0 0x1f23a000 0x0 0x100>,
+			      <0x0 0x1f23c000 0x0 0x100>,
+			      <0x0 0x1f2d0000 0x0 0x100>;
+			#phy-cells = <1>;
+			status = "ok";
+			apm,tx-boost-gain = <0x3 0x3 0x3 0x3 0x3 0x3>;
+			apm,tx-eye-tuning = <0xa 0xa 0xa 0xc 0xc 0xc>;
+		};
--
1.5.5