On 25/06/16 18:50, Martin Blumenstingl wrote:

The Amlogic reference driver uses the "mc_val" devicetree property to
configure the PRG_ETHERNET_ADDR0 register. Unfortunately it uses magic
values for this configuration.

According to the datasheet the PRG_ETHERNET_ADDR0 register is at address
0xc8834108. However, the reference driver uses 0xc8834540 instead.
According to my tests, the value from the reference driver is correct.

The updated examples are representing 0x1621 from the reference driver's
mc_val property, which is used when there is an external gbit PHY
connected.
For RMII mode PHYs mc_val 0x1800 is used in the reference driver, which
translates  would translate to "do not set any of the following
properties" (as the two bits are configured automatically):
- amlogic,enable-25mhz-phy-clk
- amlogic,mp2-clock
- amlogic,tx-delay

[...]

 			};
+
+			prg_ethernet: prg_ethernet@540 {
+				compatible = "syscon";
+				reg = <0x0 0x00540 0x0 0x8>;
+			};
 		};

A syscon is a region containing a set of miscellaneous registers used
for several reasons by several devices [1]. It this case there is really
no need to define a new syscon node since those two registers are only
used by your driver.

[1] http://lxr.free-electrons.com/source/Documentation/devicetree/bindings/mfd/syscon.txt

-- 
Carlo Caione