[Intel-gfx] [PATCH 0/3] BYT DSI Dual Link Support

[Singh, Gaurav K]

Hi Jani,

Thanks for the review comments.

Regarding the first 2 patches, I was doing almost the same thing in my 
3rd and 4th patch. But your patches are more generic.

Regarding the 3rd patch, I have a comment:

Since in case of dual link panels, few panels may require sequence to be 
sent only on Port A or Port C or both. In that case, 
for_each_dsi_port(port, intel_dsi->ports) will cause it to be sent to 
both ports.
To resolve this, in the earlier patches, intel_dsi->port was used which 
gets calculated to either 0 or 1 in mipi_exec_send_packet(). This value 
of 0 or 1 is dependent on sequence block#53.

 From now on as we will be using the _PORT3() macro for using proper 
MIPI regs, then for this scenario, we may need to have some 
workaround/hardcode type of code again. May I know your suggestion on this?

With regards,
Gaurav

On 11/14/2014 8:24 PM, Jani Nikula wrote:
> Hi Shobhit and Gaurav -
>
> I've been pondering this whole MIPI DSI pipes vs. ports thing and
> discussing with Ville and others. Rather than try and fail in explaining
> the ideas, here are some concrete patches to describe what I'd like to
> be done first.
>
> The most important thing is that we don't confuse the pipes and
> ports. Getting confused was easy with the pipe B mapping to port C, and
> the register defines being very confused/confusing about it. These
> patches attempt to fix that. Before adding dual link support, there's a
> simple function mapping the pipe to port.
>
> Next up is expanding that to handle multiple ports driven from one
> pipe. That's handled by adding intel_dsi->ports bitmap that has the bit
> set for each port that is to be driven. I've added the bitmap and some
> helpers to iterate over the configured ports, but there's no actual
> support for doing the configuration. I'm hoping you could take over from
> here. There's a sample patch about the usage.
>
> I'm sorry it's taken me so long to reply. With the new stuff coming in,
> I really think it's important to get the foundation right
> first. Especially because I'm to blame for getting some of the port/pipe
> stuff confused in the first place...
>
> BR,
> Jani.
>
>
>
> Jani Nikula (3):
>    drm/i915/dsi: clean up MIPI DSI pipe vs. port usage
>    drm/i915/dsi: add ports to intel_dsi to describe the ports being
>      driven
>    drm/i915/dsi: an example how to handle dual link for each port
>
>   drivers/gpu/drm/i915/i915_reg.h      | 303 ++++++++++++++++++-----------------
>   drivers/gpu/drm/i915/intel_dsi.c     | 151 ++++++++---------
>   drivers/gpu/drm/i915/intel_dsi.h     |  19 +++
>   drivers/gpu/drm/i915/intel_dsi_cmd.c |  76 ++++-----
>   4 files changed, 290 insertions(+), 259 deletions(-)
>