topic VPU_DecLoad() always returns VPU_DEC_RET_INVALID_PARAM in i.MX Processors

VPU_DecLoad() always returns VPU_DEC_RET_INVALID_PARAM

PiotrKrygier — Wed, 22 Feb 2023 13:20:29 GMT

Hello,

I am trying to use VPU API on IMX8MM board, but no matter what parameters I add to function VPU_DecLoad() I always get VPU_DEC_RET_INVALID_PARAM return code. What is interesting is that the same parameters, for some reason, work in GStreamer. For example, I hardcoded those parameters (copied from gststreamer debug output):

VpuDecOpenParam open_param;

open_param.CodecFormat = 6;
open_param.nReorderEnable = 1;
open_param.nChromaInterleave = 1;
open_param.nMapType = 0;
open_param.nTiled2LinearEnable = 0;
open_param.nPicWidth = 1920;
open_param.nPicHeight = 800;
open_param.nEnableFileMode = 0;
open_param.nEnableVideoCompressor = 0;
open_param.nPixelFormat = 1;
open_param.nSecureMode = 0;
open_param.nSecureBufferAllocSize = 0;

VPU_DecOpen(&handle, &open_param, &mem_info);

This will return invalid params return code. mem_info is setup using VPU_DecQueryMem and manually allocating memory in pVirtAddr and pPhyAddr variables.

Appreciate all the help!

Re: VPU_DecLoad() always returns VPU_DEC_RET_INVALID_PARAM

PiotrKrygier — Wed, 22 Feb 2023 14:39:06 GMT

Found something, that might be related to the issue:

pVirtAddr of physical memory is NULL. I have to check, how that happens.

I found out, what's going on:

VPU_DecGetMem

returns a structure, where nVirtAddr is 0. I have no idea why. Any guesses?

Re: VPU_DecLoad() always returns VPU_DEC_RET_INVALID_PARAM

PiotrKrygier — Wed, 22 Feb 2023 16:53:03 GMT

I hate replying to my own requests, but I will do it in case someone else have this problem later:

Be VERY sure that you zero VpuMemDesc structure before assigning size to it and passing to VPU_DecGetMem. It's not stated anywhere in documentation, but correct way to use it is:

VpuMemDesc mem_desc;

memset(&mem_desc, 0, sizeof(VpuMemDesc));
mem_desc.nSize = <memory size got from VPU_DecQueryMem + alignment taken from the same function>;

VPU_DecGetMem(&mem_desc);

Cheers and good luck for anyone using this API.