From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kristian Evensen Subject: Questions about bringing up MT7623 board Date: Sat, 10 Feb 2018 23:02:39 +0100 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+glpam-linux-mediatek=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-mediatek@lists.infradead.org Hello, I am currently working on trying to add mainline support for an MT7623 board I have received (Unielec U7623). I sent some initial questions about the board in the autumn, and I got OpenWRT running in a semi-stable state (with 4.9), but adding mainline support has proven tricker than I thought. After spending some days banging my head against the wall, I am starting to run out of ideas, so any pointers or tips would be greatly appreciated. With OpenWRT, I based the dts for the U7623 on mt7623-eMMC.dts. Since this file is not available in the mainline kernel, I decided to use the DTS for Banana Pi R2 as the boards seem fairly similar (and the initial goal is just to have a kernel that boots). I got a 4.14 config from a repo I found on the BPI-forum (https://github.com/frank-w/BPI-R2-4.14), added missing config symbols for 4.15, compiled a kernel and appended the dtb to the uImage. So far, so good and the kernel compiles just fine. When booting the kernel (from the eMMC), the trouble starts. The kernel seems to be loaded just fine, but after "Starting kernel ..." nothing more is written to the screen. I.e., I see the following: bootm flag=0, states=70f ## Booting kernel from Legacy Image at 84000000 ... Image Name: Linux Kernel 4.14.18-main Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 5891369 Bytes = 5.6 MiB Load Address: 80008000 Entry Point: 80008000 Verifying Checksum ... OK Loading Kernel Image ... OK Starting kernel ... I had a similar error when working on getting OpenWRT to run on the board, but then it was caused by the dtb not being appended to the kernel. When looking around online for reasons for this error, missing dtb or config-mistakes seems to be the two main reasons. I have checked for misses and errors in dts and config (both compared to the datasheet and my working 4.9 kernel), but haven't really found anything. And the changes I have made have had no effect. Does anyone have any idea about what could be wrong or where I should look? Thanks in advance for any help, Kristian