A true mainline Linux Kernel for the Pinebook Pro

[xmixahlx]

@tsys compiles fine and working (well?) so far. FYI i have numerous debug messages similar to: (using PREEMPT and DEBUG_PREEMPT)

[ 87.534574] BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u12:1/89
[ 87.534588] caller is debug_smp_processor_id+0x20/0x30
[ 87.534595] CPU: 3 PID: 89 Comm: kworker/u12:1 Not tainted 5.8.0-rc1-0.39-1-pinebookpro-hwaccel+ #1
[ 87.534597] Hardware name: Pine64 Pinebook Pro (DT)
[ 87.534605] Workqueue: writeback wb_workfn (flush-259:0)
[ 87.534612] Call trace:
[ 87.534618] dump_backtrace+0x0/0x1e0
[ 87.534622] show_stack+0x18/0x30
[ 87.534631] dump_stack+0xbc/0x114
[ 87.534635] check_preemption_disabled+0xf8/0x110
[ 87.534638] debug_smp_processor_id+0x20/0x30
[ 87.534644] ext4_mb_new_blocks+0x1b0/0x4a0
[ 87.534651] ext4_ext_map_blocks+0x618/0xce0
[ 87.534654] ext4_map_blocks+0xec/0x580
[ 87.534659] ext4_writepages+0x598/0xa80
[ 87.534666] do_writepages+0x54/0x110
[ 87.534673] __writeback_single_inode+0x3c/0x1d0
[ 87.534678] writeback_sb_inodes+0x1f8/0x3e0
[ 87.534682] __writeback_inodes_wb+0x4c/0xf0
[ 87.534686] wb_writeback+0x1dc/0x1f0
[ 87.534690] wb_workfn+0x30c/0x350
[ 87.534694] process_one_work+0x190/0x320
[ 87.534698] worker_thread+0x4c/0x400
[ 87.534704] kthread+0x104/0x140
[ 87.534709] ret_from_fork+0x10/0x24