drm/i915/iosf: Drop unused APIs

Drop unused vlv_iosf_sb_read() and vlv_iosf_sb_write().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231103201831.1037416-17-andriy.shevchenko@linux.intel.com

drm/i915: convert vlv_dpio_read()/write() from pipe to phy

vlv_dpio_read() and vlv_dpio_write() really operate on the phy, not
pipe. Passing the pipe instead of the phy as parameter is supposed to be
a convenience, but when the caller has the phy, it becomes an
inconvenience. See e.g. chv_dpio_cmn_power_well_enable() and
assert_chv_phy_powergate().

Figure out the phy in the callers, and pass phy to the dpio functions.

v2: retract one overzealous pipe->phy change (Ville)

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231114104534.4180144-3-jani.nikula@intel.com

drm/i915: split out vlv sideband registers from i915_reg.h

Add a dedicated file vlv_sideband_reg.h for the VLV/CHV sideband
registers. The sideband registers macros are needed by the same files
that need vlv_sideband.h, so include the definitions from there.

v2: Fix copyright year (Matt)

Cc: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110095740.166078-2-jani.nikula@intel.com

drm/i915: split out vlv sideband to a separate file

The VLV/CHV sideband code is pretty distinct from the rest of the
sideband code. Split it out to new vlv_sideband.[ch].

Pure code movement with relevant #include changes, and a tiny checkpatch
fix on top.

Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/755ebbbaf01fc6d306b763b6ef60f45e671ba290.1634119597.git.jani.nikula@intel.com