Starting on Xe2, the GSCCS engine reset is a 2-step process. When the
driver or the GuC hits the GDRST register, the CS is immediately reset
and a success is reported, but the GSC shim continues its reset in the
background. While the shim reset is ongoing, the CS is able to accept
new context submission, but any commands that require the shim will
be stalled until the reset is completed. This means that we can keep
submitting to the GSCCS as long as we make sure that the preemption
timeout is big enough to cover any delay introduced by the reset; since
the GSC preempt timeout is not tunable at runtime, we only need to check
that the value set in kconfig is big enough (and increase it if it
isn't).
When the shim reset completes, a specific CS interrupt is triggered,
in response to which we need to check the GSCI_TIMER_STATUS register
to see if the reset was successful or not.
Note that the GSCI_TIMER_STATUS register is not power save/restored,
so it gets reset on MC6 entry. However, a reset failure stops MC6,
so in that scenario we're always guaranteed to find the correct value.
Since we can't check the register within interrupt context, the
existing GSC worker has been updated to handle it.
The expected action to take on ER failure is to trigger a driver FLR,
but we still don't support that, so for now we just print an error. A
comment has been added to the code to keep track of the FLR requirement.
v2: Add a check for the initial timeout value (Alan)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240304145634.820684-1-daniele.ceraolospurio@intel.com
The GSC uC needs to communicate with the CSME to perform certain
operations. Since the GSC can't perform this communication directly on
platforms where it is integrated in GT, the graphics driver needs to
transfer the messages from GSC to CSME and back. The proxy flow must be
manually started after the GSC is loaded to signal to GSC that we're
ready to handle its messages and allow it to query its init data from
CSME.
Note that the component must be removed before the pci_remove call
completes, so we can't use a drmm helper for it and we need to instead
perform the cleanup as part of the removal flow.
v2: add function documentation, more targeted memory clear, clearer logs
and variable names (Alan)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Cc: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240117182621.2653049-2-daniele.ceraolospurio@intel.com
When the GSC FW is loaded, we need to inform it when a GSCCS reset is
coming and then wait 200ms for it to get ready to process the reset.
v2: move WA code to GSC file, use variable in Makefile (John)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: John Harrison <john.c.harrison@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
The GSC FW must be copied in a 4MB stolen memory allocation, whose GGTT
address is then passed as a parameter to a dedicated load instruction
submitted via the GSC engine.
Since the GSC load is relatively slow (up to 250ms), we perform it
asynchronously via a worker. This requires us to make sure that the
worker has stopped before suspending/unloading.
Note that we can't yet use xe_migrate_copy for the copy because it
doesn't work with stolen memory right now, so we do a memcpy from the
CPU side instead.
v2: add comment about timeout value, fix GSC status checking
before load (John)
Bspec: 65306, 65346
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Add the basic definitions and init function. Same as HuC, GSC is only
supported on the media GT on MTL and newer platforms.
Note that the GSC requires submission resources which can't be allocated
during init (because we don't have the hwconfig yet), so it can't be
marked as loadable at the end of the init function. The allocation of
those resources will come in the patch that makes use of them to load
the FW.
v2: better comment, move num FWs define inside the enum (John)
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
