MA35D1 打RT-Linux后系统启动异常

在kernel上打上RT-Linux补丁后，系统启动有一个异常信息，见下：

1. [ 5.098239] Nuvoton MA35D1 CAPLL/DDRPLL Cannot disable.
   
2. 
   
3. [ 5.098253] ALSA device list:
   
4. 
   
5. [ 5.098258] #0: ma35d1_IIS
   
6. 
   
7. [ 5.098483] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
   
8. 
   
9. [ 5.098506] cfg80211: failed to load regulatory.db
   
10. 
    
11. [ 5.101494] ------------[ cut here ]------------
    
12. 
    
13. [ 5.101502] WARNING: CPU: 0 PID: 1 at kernel/rcu/tree_plugin.h:297 rcu_note_context_switch+0x48/0x360
    
14. 
    
15. [ 5.101541] Modules linked in:
    
16. 
    
17. [ 5.101554] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.140-rt73 #3
    
18. 
    
19. [ 5.101569] Hardware name: Nuvoton MA35D1-SOM (DT)
    
20. 
    
21. [ 5.101576] pstate: 20000085 (nzCv daIf -PAN -UAO -TCO BTYPE=--)
    
22. 
    
23. [ 5.101590] pc : rcu_note_context_switch+0x48/0x360
    
24. 
    
25. [ 5.101607] lr : rcu_note_context_switch+0x24/0x360
    
26. 
    
27. [ 5.101624] sp : ffff80001101b5b0
    
28. 
    
29. [ 5.101630] x29: ffff80001101b5b0 x28: ffff000002888400
    
30. 
    
31. [ 5.101647] x27: ffff0000030b59e8 x26: ffff800010f54000
    
32. 
    
33. [ 5.101664] x25: 0000000000000000 x24: ffff800010ded868
    
34. 
    
35. [ 5.101681] x23: ffff8000109d12bc x22: 0000000000000000
    
36. 
    
37. [ 5.101697] x21: ffff000001840000 x20: ffff000009f56700
    
38. 
    
39. [ 5.101714] x19: ffff000009f57300 x18: ffff000001840430
    
40. 
    
41. [ 5.101731] x17: 000000003f187eef x16: 00000000f8ecbaa4
    
42. 
    
43. [ 5.101748] x15: 000001f3e7d8b0d6 x14: 000000000000001f

复制代码

修改A35D1_linux-5.10.y\drivers\tty\serial\ma35d1_serial.c文件中的以下函数。

去掉static int ma35d1serial_startup(struct uart_port *port)函数中的：
spin_lock(&up->port.lock);
spin_unlock(&up->port.lock);