While hw resources allocation for an active display during modeset, avoid
dsc hw allocation switch by finding which dsc encoders are allocated
previously and allocate same dsc hw encoders. This helps in fixing underrun
issues in below scenario of dual display power ON/OFF.
Use case: Dual DSI display setup, both are DSC enabled, primary in video mode.
--> when both displays are in powered off, all hw block are free.
--> enable second dsi display
Since LM 0/1 marked for primary, LM 2/3 allocated along with DSC 0/1
--> enable primary display
LM 0/1 allocated with DSC 2/3 encoders
--> Now power off secondary DSI
DSC 0/1 are freed up
--> Immediate modeset on primary, DSC allocation switched
LM 0/1 and DSC 0/1 allocated. DSC 2/3 are freed up as per RM but
decoupling DSC 2/3 blocks with respective pingpong or intf is not done.
This is causing underruns on primary.
Tracking which DSC blocks are freed during resource switch and programming the
respective DSC control mux configuration is not feasible and not scalable as
any other display can allocate those blocks and would require synchronizing
across display threads. So approach taken is avoid dsc resource switch itself.
Change-Id: I7f740722a52266740c4b168edc0c619e3cf68989
Signed-off-by: Prabhanjan Kandula <pkandula@codeaurora.org>
7db951ec69