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.