On Tuesday 22 April 2014, zhangfei wrote: > On 04/22/2014 04:22 PM, Arnd Bergmann wrote: > > >> It's private register of the phy marvell 88e1512. > >> To make it clearer using define instead. > >> #define MII_MARVELL_PHY_PAGE 22 > >> > >> The registers has been grouped into several pages, access register need > >> choose which page first. > > > > You shouldn't touch the PHY private registers in the main driver though, > > this should be purely handled by drivers/net/phy/marvell.c. > > > > I don't see support for 88e1512 there, only 88e1510 and lots of older > > ones, but I assume it isn't hard to add. > > > > 88e1512 driver is already supported, same as 88e1510. > #define MARVELL_PHY_ID_MASK 0xfffffff0 > So it should support 88e151x. > > Reset is required here for get_phy_id, otherwise only 0 can be get. > phy_device_create will not be called, and can not match any driver. > > However in the experiment, it is found BMCR_RESET is not required in fact. > Only hip04_mdio_write(bus, i, MII_MARVELL_PHY_PAGE, 0) has to be set. > 88e151x registers are divided into pages. > Generic MII registers is in page 0, including MII_PHYSID1 and MII_PHYSID2. > Unfortunately the default page is not 0, so get_phy_id will fail. > > So bus->reset still required to set the page to 0, prepared for get_phy_id. But it means that the hip04_mdio driver potentially won't work if connected to something other than a Marvell PHY. I noticed that the marvell_of_reg_init() does this at init time: saved_page = phy_read(phydev, MII_MARVELL_PHY_PAGE); ... /* perform init */ if (page_changed) phy_write(phydev, MII_MARVELL_PHY_PAGE, saved_page); Is this a bug? Maybe it should always set page 0 when leaving this function. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
