DC3CO is useful power state, when DMC detects PSR2 idle frame
while an active video playback, playing 30fps video on 60hz panel
is the classic example of this use case.
B.Specs:49196 has a restriction to enable DC3CO only for Video Playback.
It will be worthy to enable DC3CO after completion of each pageflip
and switch back to DC5 when display is idle because driver doesn't
differentiate between video playback and a normal pageflip.
We will use Frontbuffer flush call tgl_dc3co_flush() to enable DC3CO
state only for ORIGIN_FLIP flush call, because DC3CO state has primarily
targeted for VPB use case. We are not interested here for frontbuffer
invalidates calls because that triggers PSR2 exit, which will
explicitly disable DC3CO.
DC5 and DC6 saves more power, but can't be entered during video
playback because there are not enough idle frames in a row to meet
most PSR2 panel deep sleep entry requirement typically 4 frames.
As PSR2 existing implementation is using minimum 6 idle frames for
deep sleep, it is safer to enable DC5/6 after 6 idle frames
(By scheduling a delayed work of 6 idle frames, once DC3CO has been
enabled after a pageflip).
After manually waiting for 6 idle frames DC5/6 will be enabled and
PSR2 deep sleep idle frames will be restored to 6 idle frames, at this
point DMC will triggers DC5/6 once PSR2 enters to deep sleep after
6 idle frames.
In future when we will enable S/W PSR2 tracking, we can change the
PSR2 required deep sleep idle frames to 1 so DMC can trigger the
DC5/6 immediately after S/W manual waiting of 6 idle frames get
complete.
v2: calculated s/w state to switch over dc3co when there is an
update. [Imre]
Used cancel_delayed_work_sync() in order to avoid any race
with already scheduled delayed work. [Imre]
v3: Cancel_delayed_work_sync() may blocked the commit work.
hence dropping it, dc5_idle_thread() checks the valid wakeref before
putting the reference count, which avoids any chances of dropping
a zero wakeref. [Imre (IRC)]
v4: Used frontbuffer flush mechanism. [Imre]
v5: Used psr.pipe to extract frontbuffer busy bits. [Imre]
Used cancel_delayed_work_sync() in encoder disable path. [Imre]
Used mod_delayed_work() instead of cancelling and scheduling a
delayed work. [Imre]
Used psr.lock in tgl_dc5_idle_thread() to enable psr2 deep
sleep. [Imre]
Removed DC5_REQ_IDLE_FRAMES macro. [Imre]
v6: Used dc3co_exitline check instead of TGL and dc3co allowed_dc_mask
checks, used delayed_work_pending with the psr lock and removed the
psr2_deep_slp_disabled flag. [Imre]
v7: Code refactoring, moved most of functional code to inte_psr.c [Imre]
Using frontbuffer_bits on psr.pipe check instead of
busy_frontbuffer_bits. [Imre]
Calculating dc3co_exit_delay in intel_psr_enable_locked. [Imre]
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191003081738.22101-6-anshuman.gupta@intel.com
It was enabling and checking PSR interruptions in every transcoder
while it should keep the interruptions on the non-used transcoders
masked.
While doing this it gives us trouble on Tiger Lake if we are
reading/writing to registers of disabled transcoders since from gen12
onwards the registers are relative to the transcoder. Instead of forcing
them ON to access those registers, just avoid the accesses as they are
not needed.
v2 (Lucas):
- Explain why we can't keep accessing all transcoders
- Remove TODO about extending the irq handling to multiple instances:
when/if implementing multiple instances it's pretty clear by the
singleton psr that it needs to be extended
- Fix intel_psr_debug_set() calling psr_irq_control() with
psr.transcoder not set yet (from Imre). Now we only set the debug
register right away if psr is already enabled. Otherwise we just
record the value to be set when enabling the source.
- Do not depend on the value of TRANSCODER_A. Just be relative to it
(from Imre)
- handle psr error last so we don't schedule the work before handling
the other flags
v3:
- Adding a warning about setting reserverd bits on EDP_PSR_IMR
Cc: Imre Deak <imre.deak@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190904213419.27547-2-jose.souza@intel.com
PSR registers are a mess, some have the full address while others just
have the additional offset from psr_mmio_base.
For BDW+ psr_mmio_base is nothing more than TRANSCODER_EDP_OFFSET +
0x800 and using it makes more difficult for people with an PSR
register address or PSR register name from from BSpec as i915 also
don't match the BSpec names.
For HSW psr_mmio_base is _DDI_BUF_CTL_A + 0x800 and PSR registers are
only available in DDIA.
Other reason to make relative to transcoder is that since BDW every
transcoder have PSR registers, so in theory it should be possible to
have PSR enabled in a non-eDP transcoder.
So for BDW+ we can use _TRANS2() to get the register offset of any
PSR register in any transcoder while for HSW we have _HSW_PSR_ADJ
that will calculate the register offset for the single PSR instance,
noting that we are already guarded about trying to enable PSR in other
port than DDIA on HSW by the 'if (dig_port->base.port != PORT_A)' in
intel_psr_compute_config(), this check should only be valid for HSW
and will be changed in future.
PSR2 registers and PSR_EVENT was added after Haswell so that is why
_PSR_ADJ() is not used in some macros.
The only registers that can not be relative to transcoder are
PSR_IMR and PSR_IIR that are not relative to anything, so keeping it
hardcoded. That changed for TGL but it will be handled in another
patch.
Also removing BDW_EDP_PSR_BASE from GVT because it is not used as it
is the only PSR register that GVT have.
v5:
- Macros changed to be more explicit about HSW (Dhinakaran)
- Squashed with the patch that added the tran parameter to the
macros (Dhinakaran)
v6:
- Checking for interruption errors after module reload in the
transcoder that will be used (Dhinakaran)
- Using lowercase to the registers offsets
v7:
- Removing IS_HASWELL() from registers macros(Jani)
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190820223325.27490-1-jose.souza@intel.com
