On BDW+ M/N are double buffered and so we can easily reprogram them
during a fastset. So for eDP panels that support seamless DRRS we
can just change these without a full modeset.
For earlier platforms we'd need to play tricks with M1/N1 vs.
M2/N2 during the fastset to make sure we do the switch atomically.
Not sure the added complexity is worth the hassle, so leave it
alone for now.
The slight downside is that we have to keep the link running at
a link rate capable of supporting the highest refresh rate we
want to use. For the moment we just pick the highest mode the
panel reports and calculate the link based on that. This might
need further refinement (eg. if we run into bandwidth
restrictions)...
v2: Only use the high link rate if the platform really supports
the seamless M/N change uring fastset (ie. bdw+)
v3: Rebase due to HAS_DOUBLE_BUFFERED_M_N()
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907091057.11572-16-ville.syrjala@linux.intel.com
Add a function to get the fixed_mode with the highest clock.
The plan is to use this for the link bw calculation on seamless
DRRS panels so that we alwasy end up with the same link params
regardless of the requested refresh rate. This will allow fastset
to do seamless refresh rate changes based on userspace request
instead of having to go for a full modeset.
TODO: the function name isn't great
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907091057.11572-15-ville.syrjala@linux.intel.com
To make the fastboot checks at least somewhat sensible let's mark
the expected DPLL as the active one right after we finished the
state computation. Otherwise intel_pipe_config_compare() will
always be comparing things against NULL/0.
TODO: This is still not really right. If the previous commit
had to fall back to the other PLL then the comparisong will
now fail. I guess intel_pipe_config_compare() should rather
be comparing port_dplls[] instead. But to do that we really
should just unify every platform to use the port_dplls[]
approach whether they have any need for PLL fallbacks or not.
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907091057.11572-12-ville.syrjala@linux.intel.com
Now that we no longer fuzz M/N during fastset these should
match exctly.
In order to get a match with what the BIOS does we need to round
M/N down. And we do the opposite rounding when doing the readback.
That gets us pretty much the same thing back.
There can still be slight rounding differences between FDI M/N
vs. the DPLL output so we allow for tiny deviation in
intel_pipe_config_sanity_check().
v2: Tweak rounding/sanity check stuff a bit
Reviewed-by: Jani Nikula <jani.nikula@intel.com> #v1
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907091057.11572-10-ville.syrjala@linux.intel.com
Only reassign the pipe's DPLL if it's going through a full
.compute_config() cycle. If OTOH it's just getting modeset
eg. in order to change cdclk there doesn't seem much point in
picking a new DPLL for it.
This should also prevent .get_dplls() from seeing a funky port_clock
for DP even in cases where the readout produces a non-standard
clock and we (for some reason) have decided to not fully recompute
the state to remedy the situation.
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907091057.11572-7-ville.syrjala@linux.intel.com
Currently we calculate a lot of things (pixel rate, watermarks,
cdclk) trusting that the DPLL can generate the exact frequency
we ask it. In practice that is not true and there can be
certain amount of rounding involved.
To allow us to eventually get accurate numbers for all our
DPLL clock derived state we need to move the DPLL calculation
to hapen much earlier. To that end we hoist it up to the just
after the fastset checks. For now we just do the easy code
motion, and the actual back feeding of the final DPLL clock
into the state will come later.
A slight change here is that now .crtc_compute_clock()
can get called while the shared_dpll is still assigned.
But since .crtc_compute_clock() no longer assignes new
shared_dplls this is perfectly fine.
TODO: I'd actually like to do this before the fastset check
so that if the DPLL state should change we actually do the
modeset. Which I think is what the video aficionados want,
but it might not be what the fans of fastboot want. Not yet
sure how to reconcile those conflicting requirements...
v2: s/return/goto/ in error handling
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907091057.11572-6-ville.syrjala@linux.intel.com
This reverts commit 797e2c3f27.
Part of a series where patches were modified while applying to resolve
conflicts, leading to further conflicts between drm-misc-next and
drm-intel-next, resulting in build failures in drm-tip. To be applied
again on a baseline with drm-misc-next and drm-intel-next in sync.
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This reverts commit c6266862de.
Part of a series where patches were modified while applying to resolve
conflicts, leading to further conflicts between drm-misc-next and
drm-intel-next, resulting in build failures in drm-tip. To be applied
again on a baseline with drm-misc-next and drm-intel-next in sync.
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This reverts commit 7ae5ab4414.
Part of a series where patches were modified while applying to resolve
conflicts, leading to further conflicts between drm-misc-next and
drm-intel-next, resulting in build failures in drm-tip. To be applied
again on a baseline with drm-misc-next and drm-intel-next in sync.
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This reverts commit e1a84ba850.
Part of a series where patches were modified while applying to resolve
conflicts, leading to further conflicts between drm-misc-next and
drm-intel-next, resulting in build failures in drm-tip. To be applied
again on a baseline with drm-misc-next and drm-intel-next in sync.
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>