Am Tue, 1 Apr 2014 20:42:44 +0200 hat "Dr. H. Nikolaus Schaller" hns@goldelico.com geschrieben:
Hi,
Hmm, one of their main advertisements for the chip is that you safe power since it supports special automatic power saving features for MIPI display.
Hm, In video mode there is no power saving. Only if the panel itself has a built-in frame buffer. Then, the communication can be shut down if nothing changes. But we are all the time discussion real time image sequences with extremely high frame rate. These are the most challenging for any system. So there is nothing to save...
You didn't check the datasheet? It's right on Page 12 (Feature list):
VTCM has the following features:
"• DCS command or video bypass together with data compression (SSL segment-based & Qualcomm line-based) to reduce the bandwidth requirement during data transmission."
More info: "The Video compression unit allows compression of the video stream before going into MIPI DSI TX module for MIPI link transmission. This will reduce the MIPI link speed for lower power consumptions. It supports SSL-segment based compression"
We need to use SSL compression for rotation anyways.
"• Built-in frame buffer to support video data self-refresh, so the refresh frequency from application processor can be reduced or stopped during static frames. "
Might be useful when using it to read PDFs, when not much happens.
"• Low power mode support via frame skipping"
Hmmm... interesting when using X as well. Skipping frames when using a browser could be useful.
"• Variable pixel clock generation to dynamically change video refresh rate for power saving"
No idea exactly what that does.
I have no ideas how easy / hard that is to use, but maybe some stuff works automatically :)