> -----Original Message----- > From: Marek Vasut <ma...@denx.de> > Sent: Friday, August 7, 2020 7:53 PM > To: Wolfgang Grandegger <w...@aries-embedded.de>; U-Boot Mailing List > <u-boot@lists.denx.de> > Cc: Simon Goldschmidt <simon.k.r.goldschm...@gmail.com>; Nguyen, Dinh > <dinh.ngu...@intel.com>; Tan, Ley Foon <ley.foon....@intel.com> > Subject: Re: Revert "ARM: socfpga: Remove > socfpga_sdram_apply_static_cfg() > > On 8/7/20 1:22 PM, Wolfgang Grandegger wrote: > > > > > > Am 07.08.20 um 13:12 schrieb Marek Vasut: > >> On 8/7/20 12:58 PM, Wolfgang Grandegger wrote: > >>> Am 06.08.20 um 14:50 schrieb Marek Vasut: > >>>> On 8/6/20 2:36 PM, Wolfgang Grandegger wrote: > >>>>> Am 06.08.20 um 13:04 schrieb Marek Vasut: > >>>>>> On 8/6/20 12:53 PM, Wolfgang Grandegger wrote: > >>>>>>> This reverts commit > c5f4b805755912a3d2fe20f014b6b6ab0473bd73. > >>>>>>> > >>>>>>> Conflicts: > >>>>>>> arch/arm/mach-socfpga/misc_gen5.c > >>>>>>> > >>>>>>> Without socfpga_sdram_apply_static_cfg(), the system hangs when > >>>>>>> Linux calls altvipfb2_start_hw() of the Intel Video and Image > >>>>>>> Processing(VIP) Frame Buffer II driver > >>>>>>> (drivers/video/fbdev/altvipfb2.c) > >>>>>> > >>>>>> There is no such driver in mainline U-Boot or Linux. > >>>>> > >>>>> It's a simple frame buffer driver from linux-socfpga for the IP > >>>>> core Intel Video and Image Processing(VIP) Frame Buffer II. It > >>>>> actually hangs here when the streaming starts: > >>>>> > >>>>> https://github.com/altera-opensource/linux-socfpga/blob/socfpga-5. > >>>>> 4.44-lts/drivers/video/fbdev/altvipfb2.c#L69 > >>>>> > >>>>> I can also hang the system if I setup and start the FB with just a > >>>>> few U-Boot commands. I think the system hangs when the IP core > >>>>> starts reading the FB data from the system memory. > >>>> > >>>> I am CCing Dinh , I recall there was some discussion about hangs on > >>>> CycloneV and it was fixed recently. > >>>> > >>>>>>> , but only > >>>>>>> after a power cycle (cold boot). The issue does not show up > >>>>>>> after a soft reset (warm boot) and with v2018.11. > >>>>>> > >>>>>> See the commit message of the patch this is reverting, I believe > >>>>>> there is a deeper issue with the static config register. Can you > investigate? > >>>>> > >>>>> I read the commit message, but well, I can't follow all the details :(. > >>>>> On the other hand, it seems also not clear why the fix was added. > >>>>> Any idea what to investigate. > >>>> > >>>> The system was repeatedly rebooted in a loop, the FPGA was loaded > >>>> before Linux booted. After hundreds of reboots, the system got > >>>> stuck on setting up the static cfg register. I think there was even > >>>> another email > >>> > >>> I rebooted Linux on my MCVEVP more than 100 times with and without > >>> loading the FPGA in U-Boot. The system never hang! > >> > >> It could very well be bitstream related, wait for Simon to chime in. > >> Do you load the bitstream in U-Boot or in Linux ? > > > > I load it in U-Boot. And I repeated the test more than 1000 times (100 > > above is a typo)! OK, let's wait for more input. > > Sorry for pushing back on this, the issue keeps coming back and until we get > to the bottom of this, I don't want to see applying and reverting a patch back > and forth. And getting to the real bottom of this seems to be particularly > difficult task. > > Does your bitstream use the DRAM bridge (F2S) ? I think it does. The one I > used didn't as far as I remember. So maybe the way forward is to only apply > static cfg if the bridge is enabled.
We have another email thread before about restore back socfpga_sdram_apply_static_cfg() function. Yes, we talked about only apply static cfg bit if the F2S port is enabled. But, no final decision previously. I can re-submit the patches if you are okay with this approach. Wolfgang, I have downstream patches for checking F2S port before apply static cfg bit. Can you try these 2 patches on your side if they solve your issue? I can't reproduce the issue on my side. https://github.com/altera-opensource/u-boot-socfpga/commit/ca64e19e40224091b7f57b63ddd7ea9cdc6e8d44 https://github.com/altera-opensource/u-boot-socfpga/commit/11ff7b9ce3abc5e61f44997a017b175c371eeee9 Regards Ley Foon
