Documentation: Add APM X-Gene SoC 15Gbps Multi-purpose PHY driver binding documentation

This patch adds the APM X-Gene SoC 15Gbps Multi-purpose PHY driver binding
documentation.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

1 files changed, 79 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/phy/apm-xgene-phy.txt b/Documentation/devicetree/bindings/phy/apm-xgene-phy.txt
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index 000000000000..5f3a65a9dd88
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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".
+- reg                   : PHY memory resource is the SDS PHY access resource.
+- #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), 3 (USB), and 4 (XFI).
+
+Optional properties:
+- status                : Shall be "ok" if enabled or "disabled" if disabled.
+                          Default is "ok".
+- clocks                : Reference to the clock entry.
+- 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 each (up to 3)
+                          supported link speed on the host. Range from 0 to
+                          127 in unit of one bit period. Default is 10.
+- 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 each (up to 3)
+                          supported link speed on the host. Default is 0.
+- apm,tx-boost-gain     : Frequency boost AC (LSB 3-bit) and DC (2-bit)
+                          gain control. Two set of 3-tuple setting for each
+                          (up to 3) supported link speed on the host. Range is
+                          between 0 to 31 in unit of dB. Default is 3.
+- apm,tx-amplitude      : Amplitude control. Two set of 3-tuple setting for
+                          each (up to 3) supported link speed on the host.
+                          Range is between 0 to 199500 in unit of uV.
+                          Default is 199500 uV.
+- apm,tx-pre-cursor1    : 1st pre-cursor emphasis taps control. Two set of
+                          3-tuple setting for each (up to 3) supported link
+                          speed on the host. Range is 0 to 273000 in unit of
+                          uV. Default is 0.
+- apm,tx-pre-cursor2    : 2st pre-cursor emphasis taps control. Two set of
+                          3-tuple setting for each (up to 3) supported link
+                          speed on the host. Range is 0 to 127400 in unit uV.
+                          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 each
+                          supported link speed on the host.
+                           0 = 1-2Gbps
+                           1 = 2-4Gbps (1st tuple default)
+                           2 = 4-8Gbps
+                           3 = 8-15Gbps (2nd tuple default)
+                           4 = 2.5-4Gbps
+                           5 = 4-5Gbps
+                           6 = 5-6Gbps
+                           7 = 6-16Gbps (3rd tuple default)
+
+NOTE: PHY override parameters are board specific setting.
+
+Example:
+                phy1: phy@1f21a000 {
+                        compatible = "apm,xgene-phy";
+                        reg = <0x0 0x1f21a000 0x0 0x100>;
+                        #phy-cells = <1>;
+                        status = "disabled";
+                };
+
+                phy2: phy@1f22a000 {
+                        compatible = "apm,xgene-phy";
+                        reg = <0x0 0x1f22a000 0x0 0x100>;
+                        #phy-cells = <1>;
+                        status = "ok";
+                };
+
+                phy3: phy@1f23a000 {
+                        compatible = "apm,xgene-phy";
+                        reg = <0x0 0x1f23a000 0x0 0x100>;
+                        #phy-cells = <1>;
+                        status = "ok";
+                };