not enough contiguous DMA-capable memory because
CONFIG_CMA_SIZE_MBYTES is set too low etc
I have the same error message running a standard ubuntu kernel 4.15.0-21-generic with 16
GB RAM. I'm not familiar with setting the right kernel options. My config file for the
kernel just shows:
CONFIG_CMA=y
# CONFIG_CMA_DEBUG is not set
# CONFIG_CMA_DEBUGFS is not set
CONFIG_CMA_AREAS=7
I haven't been able to receive a FM signal yet. My output from the fl2k_test shows:
sudo fl2k_test -s 162e6
Allocating 6 zero-copy buffers
libusb: error [op_dev_mem_alloc] alloc dev mem failed errno 12
Failed to allocate zero-copy buffer for transfer 4
Falling back to buffers in userspace
Reporting PPM error measurement every 10 seconds...
Press ^C after a few minutes.
real sample rate: 113962068 current PPM: -296530 cumulative PPM: -296530
real sample rate: 113975309 current PPM: -296449 cumulative PPM: -296489
real sample rate: 114139355 current PPM: -295436 cumulative PPM: -296136
Do I need to change my kernel settings or will the device simply won't work?