topic Re: question about frame buffer access with 2700G decoding in Software Archive

question about frame buffer access with 2700G decoding

easyheart — Fri, 16 Jun 2006 09:08:23 GMT

Hello everybody,

I have got a problem that need your help.In 2700G video decoding, there is sometime that I need to access the data that is just decoded.To be more specific,right after the command GXVA_CMD_IMAGE_WRITE is sent out, I would like to read the data ofthis macroblock in the frame buffer, but I found that theexpecting data was not available, which meantthis macroblock data was not written toframe buffer yet.

My question is: how doI judge that the writing operation is finished,oris there any way that I can tell the completment of the operation?

Thanks!

Re: question about frame buffer access with 2700G decoding

Chuck_De_Sylva — Tue, 20 Jun 2006 03:19:35 GMT

You can issue a STORE DWORD command after the indicated operation. When the address pointed to by the STOREDW command gets updated, you know the STORE command...and all other commands before it...have compeleted.

Re: question about frame buffer access with 2700G decoding

Chuck_De_Sylva — Tue, 20 Jun 2006 05:00:00 GMT

Also, you must issue a MI_FLUSH prior to the Store DWORD, to ensure the command has actually completed.