From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Schwingen Date: Fri, 22 Feb 2008 16:05:34 +0100 Subject: [U-Boot-Users] [PATCH] Add support for Generic PHY in macb In-Reply-To: <20080222135209.026eb091@dhcp-252-066.norway.atmel.com> References: <596876.36735.qm@web26215.mail.ukl.yahoo.com> <20080222135209.026eb091@dhcp-252-066.norway.atmel.com> Message-ID: <47BEE4BE.4060805@discworld.dascon.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Haavard Skinnemoen wrote: > All MII-capable PHYs should have a working PHYSID1 register. If it > doesn't, something is broken. > It depends - I am not sure if there are PHYs which simply do not implement MDIO, but at least for ethernet switches, such chips do exist. > So I think the CONFIG_GENERIC_PHY name is misleading -- the test is > generic enough as is. CONFIG_BROKEN_PHY would be better, if there's > really no way to get your PHY to behave. > Right. Or CONFIG_PHY_NO_MDIO or something like that. This is in the direction of CONFIG_MII_ETHSWITCH which is used eg. by AcTux-2 for this purpose. > But note that if MDIO communication isn't working, autonegotiation > won't work, and the speed and duplex settings will most likely be > wrong. So I don't think simply #ifdefing out that sanity check is > really going to solve any problems. > The chip may do autonegotiation by default, however, the MAC driver still needs to know about the negotiated speed/duplex, so unless there is some board-specific way to read those (eg. by GPIO pins), only one speed/duplex will work and all other modes will be broken. This is different from the case with the hardwired ethernet switch - in case of the switch, we know that the MII port is always running at 100Mbps, full-duplex. cu Michael