[PATCH 1/2] dts: socfpga: Add ethernet support on Altera's SOCFPGA platform
Dinh Nguyen
dinh.linux at gmail.com
Thu Sep 26 23:27:55 EDT 2013
Hi Stephen,
On 9/26/13 6:21 PM, Stephen Warren wrote:
> On 09/24/2013 03:11 PM, dinguyen at altera.com wrote:
>> From: Dinh Nguyen <dinguyen at altera.com>
>>
>> The STMMAC Ethernet controller in SOCFPGA requires setting a register for
>> the phy-mode that is outside of the ethernet IP. This register resides in
>> the System Manager block. So we define a new DTS binding
>> "altr,sysmgr-phy-mask". This binding's property is a bitmask that can be
>> used to set the correct register bit.
>> diff --git a/Documentation/devicetree/bindings/net/stmmac-altr-socfpga.txt b/Documentation/devicetree/bindings/net/stmmac-altr-socfpga.txt
>> +* altr,sysmgr-phy-mask: This property contains the bitmask that is needed to
>> + set the appropriate register bits for the phy-mode in the System Manager.
>> + The value should be:
>> + -Ethernet Controller 1 (gmac0) = 0x3
>> + -Ethernet Controller 2 (gmac1) = 0xC
> Wouldn't you need a phandle to the sysmgr node so that the driver could
> be located, and a register number within its register block too? Or,
> does sysmgr know which register to poke? If so, couldn't the API take
> just a device index rather than a bitmask instead, and calculate the
> mask itself?
The function that pokes this register is a platform specific init
function call from the driver, so the function knows which register in
the the sysmgr to poke. The first byte of the register has controls for
both ethernet controllers. I thought it would be better to use a mask to
be used to differentiate between each controller.
Thanks,
Dinh
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