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! > exchange where the suggestion was to make this apply_static_cfg optional > and only use it when the DRAM port is enabled in the quartus design. > Maybe that is the way out of this ? Yep. Wolfgang
