drm/i915/bdw: Add support for DRRS to switch RR
drm/i915/bdw: Add support for DRRS to switch RR

For Broadwell, there is one instance of Transcoder MN values per transcoder.
For dynamic switching between multiple refreshr rates, M/N values may be
reprogrammed on the fly. Link N programming triggers update of all data and
link M & N registers and the new M/N values will be used in the next frame
that is output.

V2: [By Ram]: intel_dp_set_m_n() is rewritten to accommodate
	gen >= 8 [Rodrigo]
V3: Coding style correction [Ram]
V4: [By Ram] intel_dp_set_m_n modifications are moved into a
	separate patch, retaining only DRRS related changes here [Rodrigo]

Signed-off-by: Vandana Kannan <dd1566850b3aa5eb50ae774853f73d1deea1592d@intel.com>
Signed-off-by: Pradeep Bhat <923b480366e123064077282fa161c4a8fff3506b@intel.com>
Signed-off-by: Ramalingam C <768e1457322272d5ef8bc0a8b8c1682e7bdfa18a@intel.com>
Reviewed-by: Rodrigo Vivi <f714145d6ee82178e54021e0c168f56d17b53c9c@intel.com>
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs