Re: [PATCHv2 0/3] Intel FPGA VIP Frame Buffer II DRM Driver

["Ong, Hean Loong" <hean.loong.ong-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

On Wed, 2017-05-03 at 13:28 -0700, Eric Anholt wrote:
> hean.loong.ong@intel.com writes:
> 
> > 
> > From: Ong Hean Loong <hean.loong.ong@intel.com>
> > 
> > Hi,
> > 
> > The new Intel Arria10 SOC FPGA devkit has a Display Port IP
> > component 
> > which requires a new driver. This is a virtual driver in which the
> > FGPA hardware would enable the Display Port based on the
> > information
> > and data provided from the DRM frame buffer from the OS. Basically
> > all
> > all information with reagrds to resolution and bits per pixel are
> > pre-configured on the FPGA design and these information are fed to
> > the driver via the device tree information as part of the hardware 
> > information.
> I started reviewing the code, but I want to make sure I understand
> what's going on:
> 
> This IP core isn't displaying contents from system memory on some
> sort
> of actual physical display, right?  It's a core that takes some input
> video stream (not described in the DT or in this driver) and stores
> it
> to memory?

If the IP Core you are referring to is some form of GPU then in this
case we are using the Intel FPGA Display Port Framebuffer IP. It does
display contents streamed from the ARM/Linux system to the Display Port
of the physical Monitor.

Below a simple illustration of the system:

ARM/Linux --DMA-->Intel FPGA Display Port Framebuffer IP
				|
				|
			Physical Connection
			Display Port