From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Christophe PLAGNIOL-VILLARD Date: Wed, 28 Jan 2009 18:23:22 +0100 Subject: [U-Boot] [PATCH v2 5/9] AVR32: macb - Disable 100mbps if clock is slow In-Reply-To: References: <7e5f5fd7693284246714c42b6a3014f82f670b82.1232710611.git.gunnar@rangoy.com> <20090123153856.GA16585@game.jcrosoft.org> Message-ID: <20090128172322.GC8355@game.jcrosoft.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de > >> + > >> +#ifdef CONFIG_MACB_FORCE10M > >> + printf("%s: 100Mbps is not supported on this board - forcing 10Mbps.\n", > >> + netdev->name); > >> + > >> + adv &= ~ADVERTISE_100FULL; > >> + adv &= ~ADVERTISE_100HALF; > >> + adv &= ~ADVERTISE_100BASE4; > >> +#endif > > not a fan > > could you be more specific about the problem? > > > > Best Regards, > > J. > > > > On the EVK1100 board, the CPU (UC3A0512) is connected to the PHY via an > RMII bus. This requires the CPU clock to be at least 50 MHz. > Unfortunately, the chip on current EVK1100 boards may be unable to run > at more than 50 MHz, and with the oscillator on the board, the closest > frequency we can generate is 48 MHz. IMHO It's a HW design error to not use the MII > > This patch makes it possible to limit the macb to 10 MBit for this > case. We are open for suggestions for other solutions. I guest you may need to disable the phy auto config mode and force him to be see as a 10Mbps phy evenif it's a 10/100 Best Regards, J.