From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Date: Mon, 21 Mar 2016 20:11:54 -0600 Subject: [U-Boot] [PATCH v2] serial: pl01x: Add support for devices with the rate pre-configured. In-Reply-To: <56EE3DD0.5020300@wwwdotorg.org> References: <1457918214-14152-1-git-send-email-eric@anholt.net> <56E8C6BB.8070805@wwwdotorg.org> <56EE3DD0.5020300@wwwdotorg.org> Message-ID: <56F0A9EA.20701@wwwdotorg.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 03/20/2016 12:06 AM, Stephen Warren wrote: > On 03/15/2016 08:36 PM, Stephen Warren wrote: >> On 03/13/2016 07:16 PM, Eric Anholt wrote: >>> For Raspberry Pi, we had the input clock rate to the pl011 fixed in >>> the rpi.c file, but it may be changed by firmware due to user changes >>> to config.txt. Since the firmware always sets up the uart (default >>> 115200 output unless the user changes it), we can just skip our own >>> uart init to simplify the boot process and more reliably get serial >>> output. >> >> Tested-by: Stephen Warren >> # on RPi B+ and RPi 2 > > Sorry, I take this Tested-by back. With the latest firmware (which has > some modifications intended to initialize either the PL01x or the mini > UART depending on which the kernel will actually use), this patch causes > U-Boot not to boot at all. I'm pretty sure this is a FW bug (since even > without this patch the UART doesn't work, but U-Boot does at least boot > and can be used over HDMI/usbkbd), but I'd still prefer not to apply > this until the FW is working again and we can double-check everything. > > Hopefully this will be resolved in > https://github.com/raspberrypi/firmware/issues/553 soon. We can go ahead with this patch now; the FW behaviour has been accepted as a bug, and fixed in a new FW release.