Re: [U-Boot] [PATCH 1/2] net: phy: micrel: add documentation for Micrel KSZ90x1 binding

[Joe Hershberger]

On Wed, Jan 27, 2016 at 3:45 PM,   wrote:
> From: Dinh Nguyen 
>
> Add the DTS documentation for the Micrel KSZ90x1 binding.
>
> The original document was from:
> [commit 4b405efbe12de28b26289282b431323d73992381 from the Linux kernel]
>
> This takes the original document and adds a clarification on how the skew
> values are represented in the code.
>
> References:
>
> Micrel ksz9021rl/rn Data Sheet, Revision 1.2. Dated 2/13/2014.
> http://www.micrel.com/_PDF/Ethernet/datasheets/ksz9021rl-rn_ds.pdf
>
> Micrel ksz9031rnx Data Sheet, Revision 2.1. Dated 11/20/2014.
> http://www.micrel.com/_PDF/Ethernet/datasheets/KSZ9031RNX.pdf
>
> Signed-off-by: Dinh Nguyen 

Acked-by: Joe Hershberger 
___
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot

[U-Boot] [PATCH 1/2] net: phy: micrel: add documentation for Micrel KSZ90x1 binding

[dinguyen]

From: Dinh Nguyen 

Add the DTS documentation for the Micrel KSZ90x1 binding.

The original document was from:
[commit 4b405efbe12de28b26289282b431323d73992381 from the Linux kernel]

This takes the original document and adds a clarification on how the skew
values are represented in the code.

References:

Micrel ksz9021rl/rn Data Sheet, Revision 1.2. Dated 2/13/2014.
http://www.micrel.com/_PDF/Ethernet/datasheets/ksz9021rl-rn_ds.pdf

Micrel ksz9031rnx Data Sheet, Revision 2.1. Dated 11/20/2014.
http://www.micrel.com/_PDF/Ethernet/datasheets/KSZ9031RNX.pdf

Signed-off-by: Dinh Nguyen 
---
 doc/device-tree-bindings/net/micrel-ksz90x1.txt | 165 
 1 file changed, 165 insertions(+)
 create mode 100644 doc/device-tree-bindings/net/micrel-ksz90x1.txt

diff --git a/doc/device-tree-bindings/net/micrel-ksz90x1.txt 
b/doc/device-tree-bindings/net/micrel-ksz90x1.txt
new file mode 100644
index 000..307f53f
--- /dev/null
+++ b/doc/device-tree-bindings/net/micrel-ksz90x1.txt
@@ -0,0 +1,165 @@
+Micrel KSZ9021/KSZ9031 Gigabit Ethernet PHY
+
+Some boards require special tuning values, particularly when it comes to
+clock delays. You can specify clock delay values by adding
+micrel-specific properties to an Ethernet OF device node.
+
+Note that these settings are applied after any phy-specific fixup from
+phy_fixup_list (see phy_init_hw() from drivers/net/phy/phy_device.c),
+and therefore may overwrite them.
+
+KSZ9021:
+
+  All skew control options are specified in picoseconds. The minimum
+  value is 0, the maximum value is 1800, and it is incremented by 120ps
+  steps.
+
+  Optional properties:
+
+- rxc-skew-ps : Skew control of RXC pad
+- rxdv-skew-ps : Skew control of RX CTL pad
+- txc-skew-ps : Skew control of TXC pad
+- txen-skew-ps : Skew control of TX CTL pad
+- rxd0-skew-ps : Skew control of RX data 0 pad
+- rxd1-skew-ps : Skew control of RX data 1 pad
+- rxd2-skew-ps : Skew control of RX data 2 pad
+- rxd3-skew-ps : Skew control of RX data 3 pad
+- txd0-skew-ps : Skew control of TX data 0 pad
+- txd1-skew-ps : Skew control of TX data 1 pad
+- txd2-skew-ps : Skew control of TX data 2 pad
+- txd3-skew-ps : Skew control of TX data 3 pad
+
+KSZ9031:
+
+  All skew control options are specified in picoseconds. The minimum
+  value is 0, and the maximum is property-dependent. The increment
+  step is 60ps.
+
+  The KSZ9031 hardware supports a range of skew values from negative to
+  positive, where the specific range is property dependent. All values
+  specified in the devicetree are offset by the minimum value so they
+  can be represented as positive integers in the devicetree since it's
+  difficult to represent a negative number in the devictree.
+
+  The following 5-bit values table apply to rxc-skew-ps and txc-skew-ps.
+
+  Pad Skew Value   Delay (ps)  Devicetree Value
+  --
+  0_   -900ps  0
+  0_0001   -840ps  60
+  0_0010   -780ps  120
+  0_0011   -720ps  180
+  0_0100   -660ps  240
+  0_0101   -600ps  300
+  0_0110   -540ps  360
+  0_0111   -480ps  420
+  0_1000   -420ps  480
+  0_1001   -360ps  540
+  0_1010   -300ps  600
+  0_1011   -240ps  660
+  0_1100   -180ps  720
+  0_1101   -120ps  780
+  0_1110   -60ps   840
+  0_   0ps 900
+  1_   60ps960
+  1_0001   120ps   1020
+  1_0010   180ps   1080
+  1_0011   240ps   1140
+  1_0100   300ps   1200
+  1_0101   360ps   1260
+  1_0110   420ps   1320
+  1_0111   480ps   1380
+  1_1000   540ps   1440
+  1_1001   600ps   1500
+  1_1010   660ps   1560
+  1_1011   720ps   1620
+  1_1100   780ps   1680
+  1_1101   840ps   1740
+  1_1110   900ps   1800
+  1_   960ps   1860
+
+  The following 4-bit values table apply to the txdX-skew-ps, rxdX-skew-ps
+  data pads, and the rxdv-skew-ps, txen-skew-ps control pads.
+
+  Pad Skew Value   Delay (ps)  Devicetree Value
+  --
+   -420ps  0
+  0001 -360ps  60
+  0010 -300ps  120
+  0011 -240ps  180
+  0100 -180ps  240
+  0101 -120ps  300
+  0110 -60ps