cant run with armv8 & t820

[PsymonLi]

i use armv8 & t820,i can use mali lib to compile it,and use the opencl-dev packge,there is a error

[09:06:04] Started sgminer 5.5.6-ARM-RC1
[09:06:04] * using Jansson 2.7
[09:06:04] Error -1001: clGetPlatformsIDs failed (no OpenCL SDK installed?)
[09:06:04] clDevicesNum returned error, no GPUs usable
[09:06:04] All devices disabled, cannot mine!

and when i use the mali libopencl.so,it show the error msg

[09:09:04] Started sgminer 5.5.6-ARM-RC1
[09:09:04] * using Jansson 2.7
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
ERROR: clGetPlatformIDs from stub libOpenCL.so library called! This library can be used to resolve OpenCL symbols at compile time but must not be in your runtime path (You need to use a real OpenCL implementation, this one is empty)
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[09:09:04] Error -5: clGetPlatformsIDs failed (no OpenCL SDK installed?)
[09:09:04] clDevicesNum returned error, no GPUs usable
[09:09:04] All devices disabled, cannot mine!

[wll1rah]

You need to check with clinfo command if that doesn't show a platform from ARM with a processor of Mali T820 you don't have the drivers installed correctly