On 11/18/2010 12:40 PM, Grant Likely wrote:
On Wed, Nov 17, 2010 at 03:54:30PM -0800, David Daney wrote:
Some aspects of PHY initialization are board dependent, things like
indicator LED connections and some clocking modes cannot be determined
by probing. The dev_flags element of struct phy_device can be used to
control these things if an appropriate value can be passed from the
Ethernet driver. We run into problems however if the PHY connections
are specified by the device tree. There is no way for the Ethernet
driver to know what flags it should pass.
If we are using the device tree, the struct phy_device will be
populated with the device tree node corresponding to the PHY, and we
can extract extra configuration information from there.
The next question is what should the format of that information be?
It is highly device specific, and the device tree representation
should not be tied to any arbitrary kernel defined constants. A
straight forward representation is just to specify the exact bits that
should be set using the "marvell,reg-init" property:
phy5: ethernet-...@5 {
reg =<5>;
device_type = "ethernet-phy";
Some notes:
- device_type is only relevant for real openfirmware platforms. It
should not appear in dts files.
Documentation/powerpc/dts-bindings/phy.txt says device_type should be
here. I can remove it from my patch comment, but should it also be
removed from the phy.txt file?
- This example phy node needs a compatible property
Ok, what would you suggest? Something like:
compatible = "marvell,88e1145";
I can certainly do that, but I would note that the kernel probes these
things and would completely ignore the compatible property.
- This new binding needs to be documented. You can use devicetree.org.
Agreed, I was planning to do that once the patch was approved.
Where would that go? Vendor:Marvell, or Type:PHY/compatible=marvell,*
... or somewhere else?
marvell,reg-init =
<0x00030010 0x5777>, /* Reg 3,16<- 0x5777 */
<0x00030011 0x00aa>, /* Reg 3,17<- 0x00aa */
<0x00030012 0x4105>, /* Reg 3,18<- 0x4105 */
<0x00030013 0x0060>; /* Reg 3,19<- 0x0060 */
<0x00020015 0x00300000>; /* clear bits 4..5 of Reg 2,21 */
};
Thanks,
David Daney
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