I’ve just compiled the Linux 4.1 LTSI kernel and Poky. I’m able to boot the kernel on my DE0-nano-SoC board, using the default device tree that comes with the kernel. dmesg seems fine so far, no errors. Though /dev/fpga0 is missing.
I can also see successfull registering of the Altera FPGA Manager driver:
Jun 21 14:44:32 cyclone5 kernel: [ 1.985422] fpga_manager fpga0: Altera SOCFPGA FPGA Manager registered
Jun 21 14:44:32 cyclone5 kernel: [ 1.992306] altera_hps2fpga_bridge ff400000.fpga_bridge: fpga bridge [lwhps2fpga] registered
Jun 21 14:44:32 cyclone5 kernel: [ 2.022307] altera_hps2fpga_bridge ff500000.fpga_bridge: fpga bridge [hps2fpga] registered
Jun 21 14:44:32 cyclone5 kernel: [ 2.030919] fpga-region soc:base_fpga_region: FPGA Region probed
According to the driver code in “drivers/fpga/fpga-mgr.c”, the device is registered immediately before “Altera SOCFPGA FPGA Manager registered” is printed out. So it seems that the registering process was successfull.
Did anyone else see this behavior with the 4.1 LTSI kernel? Any ideas what is causing this?