From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulf Samuelsson Date: Fri, 30 Nov 2007 00:45:59 +0100 Subject: [U-Boot-Users] MII / RMII References: <1196375148.13652.156.camel@elrond.atmel.sweden> <474F435B.8050303@qstreams.com> Message-ID: <021601c832e3$e7146e60$dcc4af0a@atmel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de > Ulf Samuelsson wrote: >> tor 2007-11-29 klockan 19:51 +0100 skrev Guennadi Liakhovetski: >> >>> Hi, >>> >>> 1. Does it make sense at all to define CONFIG_RMII without defining >>> CONFIG_MII? The question is meant not really theoretical as in what >>> meaning RMII has, rather how the macro CONFIG_RMII is supposed to be used? >>> For example, tests like >>> >>> >> >> I think that if you use an Ethernet and need to differentiate >> between MII and RMII they should be mutually exclusive. >> You either define CONFIG_RMII OR CONFIG_MII but not both. >> If you have a PHY on the chip, then you do not define any of the two. >> > Not quite. I've argued that both CONFIG_MII and CONFIG_RMII are > pointless, but if they did have a purpose it would be to set up the link > between a MAC and a PHY on the MAC side. The bottom line is that if > CONFIGs like this are going to be used for hardware initialization they > need to be much more specific. > You need to know which PHY you are going to use, and you need to know if you are going to connect using RMII or MII so you need to have some kind of configuration. Once the configuration for MII/RMII is known, then each chip driver will have a very few things which can vary. I think the pin multiplexing is the key thing that could be controlled by these things. Each chip will have limited > regards, > Ben Best Regards Ulf Samuelsson ulf at atmel.com Atmel Nordic AB Mail: Box 2033, 174 02 Sundbyberg, Sweden Visit: Kavalleriv?gen 24, 174 58 Sundbyberg, Sweden Phone +46 (8) 441 54 22 Fax +46 (8) 441 54 29 GSM +46 (706) 22 44 57