问题描述：

当点击录像后，终端打印如下的log信息：

[   69.354381]  rockchip_ion_cma: Fail to allocate(b6f000) buffer
04-01 15:20:40 video       mpp_ion: ion_ioctl c0144900 failed with code -1: Operation not permitted
04-01 15:20:40 video       mpp_ion: allocator_ion_alloc ion_alloc failed ret -1
04-01 15:20:40 video       mpp_buffer: mpp_buffer_create failed to create buffer with size 11985408
04-01 15:20:40 video       hal_h264e_rkv: h264e_rkv_allocate_buffers hw_rec_buf[1] get failed
04-01 15:20:40 video       hal_h264e_rkv: hal_h264e_rkv_control allocate buffers failed
04-01 15:20:40 video       mpp: command 320011 param 0xa4f1e618 ret -4
04-01 15:20:40 video       mpi control pre alloc buff failedmpp_thread: MPP_THREAD_STOPPING status set mThread 0x4e3d58
04-01 15:20:40 video       mpp_buffer: mpp_buffer_ref_dec found non-positive ref_count 0 caller h264e_rkv_allocate_buffers
04-01 15:20:40 video       hal_h264e_rkv: h264e_rkv_free_buffers hw_dsp_buf[0] put failed

通过log信息发现是因为ion的内存不足所导致的。所以需要在linux内核中的dts文件中加大ion cam内存相关的大小。如下所示：修改到最大380M。问题即可得到解决。

  ion_cma: rockchip,ion-heap@4 { /* CMA HEAP */
             compatible = "rockchip,ion-heap";
             rockchip,ion_heap = <4>;
         //  reg = <0x00000000 0x04400000>; /* 68MB */           
         //  reg = <0x00000000 0x08000000>; /* 128MB */
         //  reg = <0x00000000 0x09000000>; /* 144MB */  
         //  reg = <0x00000000 0x0C000000>; /* 192MB */  
         //  reg = <0x00000000 0x11800000>; /* 280MB */
             reg = <0x00000000 0x17C00000>; /* 380MB */
         };