From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tianrui Wei Date: Thu, 13 May 2021 13:06:59 +0800 Subject: [PATCH V4 2/2] riscv: board: Support OpenPiton SoC In-Reply-To: References: <5f04532e-bbe8-2ebf-5493-9e0b45a6a8ec@gmail.com> <3712f278-88d3-ae1a-03fb-04d0083d90ba@gmail.com> <080ee3b8-b3ae-c57d-2760-bb4e0c2c9706@gmail.com> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Sean, On 5/13/2021 1:14 AM, Sean Anderson wrote: > > [snip] > >> On 5/8/2021 11:14 PM, Sean Anderson wrote: >>> On 5/8/21 12:57 AM, Tianrui Wei wrote: >>>> On 5/7/2021 9:03 PM, Sean Anderson wrote: >>>>> On 5/6/21 11:48 PM, Tianrui Wei wrote: >>>>>> On 5/7/2021 11:41 AM, Sean Anderson wrote: >>>>>>> On 5/6/21 11:28 PM, Tianrui Wei wrote: >>>>>>>> On 5/7/2021 11:15 AM, Sean Anderson wrote: >>>>>>>>> On 5/6/21 11:06 PM, Tianrui Wei wrote: >>>>>>>>>> On 5/7/2021 10:32 AM, Sean Anderson wrote: >>>>>>>>>>> Please use a log without debug uart. >>>>>>>>>>> >>>>>>>>>> So this is the part where it was a little confusing. Disabling >>>>>>>>>> debug uart acutally doesn't work for some reason, so we had to >>>>>>>>>> keep it open. Will submit another patch if we got it working >>>>>>>>>> with debug uart turned off. >>>>>>>>> >>>>>>>>> This is a bit of a strange request, but can you try adding >>>>>>>>> some nops() >>>>>>>>> (around 10-30) to some function (e.g. board_init). I've been >>>>>>>>> having >>>>>>>>> alignment problems in k210, so it could be something similar. >>>>>>>>> >> I was wondering if you have any idea what may cause the alignment >> problems, we're also hitting it constantly and adding nops seems to >> have no impact so far. > > I have no idea :) > > If adding nop()s doesn't solve it, it may not be an alignment problem. > You can also try switching from -Os to -O2, which should move things > around a bit. > > My attempts to dig into this have been stymied by the poor debugging > tools for the k210. The upstream openocd port only supports debugging > hart 0. While Canaan's fork supports debugging both harts, you must pick > the one to debug when launching the debugger. And both debuggers are > very buggy themselves. > > The other problem on the k210 at least is that the typical failure mode > (trying to read from unaddressable/unmapped addresses) hangs the bus. > This also has the tendancy of hanging the jtag debug port. I did try to switch from -Os to -O2, and it didn't help either. I've also encountered the same debugger situation unfortunately, so I have not much luck finding the faulty instruction either.? Maybe we should bring this issue up with the others along the compilation error? Thanks, Tianrui > > --Sean