The latest GuC firmware includes a number of interface changes that
require driver updates to match.

* Starting from Gen11, the ID to be provided to GuC needs to contain
  the engine class in bits [0..2] and the instance in bits [3..6].

  NOTE: this patch breaks pointer dereferences in some existing GuC
  functions that use the guc_id to dereference arrays but these functions
  are not used for now as we have GuC submission disabled and we will
  update these functions in follow up patch which requires new IDs.

* The new GuC requires the additional data structure (ADS) and associated
  'private_data' pointer to be setup. This is basically a scratch area
  of memory that the GuC owns. The size is read from the CSS header.

* There is now a physical to logical engine mapping table in the ADS
  which needs to be configured in order for the firmware to load. For
  now, the table is initialised with a 1 to 1 mapping.

* GUC_CTL_CTXINFO has been removed from the initialization params.

* reg_state_buffer is maintained internally by the GuC as part of
  the private data.

* The ADS layout has changed significantly. This patch updates the
  shared structure and also adds better documentation of the layout.

* While i915 does not use GuC doorbells, the firmware now requires
  that some initialisation is done.

* The number of engine classes and instances supported in the ADS has
  been increased.
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Tomasz Lis <tomasz.lis@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201028145826.2949180-2-John.C.Harrison@Intel.com