vgsp: GR server-managed context commit experiments (EVICT, VA promote, external path)

Rung-2 bisection after the GET_CTX_BUFFER_INFO ABI fix made the server ctx
geometry visible (8 buffers; MAIN 0x133000 FBMEM, PATCH 0x5000):

- map the server MAIN/PATCH at the ladder ctx VAs with FBMEM PTEs and send
  the UVM-shape VA-only promote (bInitialize=0, bNonmapped=0). On the shared
  VAS the per-entry VA branch calls vaListSetManaged(NV_FALSE) and returns
  0x40 because the server pre-booked MAIN as managed; EVICT_CTX (status 0)
  does not release that booking.
- try the same VA promote on the external VAS where the server did not book
  (kgrctxMapCtxBuffers early-returns): the promote never replies (-110) and
  leaves the device in the locked fail-safe (WPR2 up, unbound). Do not repeat
  this shape without a new hypothesis.
- FBMEM physAttr selection for the server MAIN fixed (aperture 2 -> 0x4);
  gsp_phys_rmcall_srv_ctxcommit parameter added (0 = pure server-managed,
  no client promote).
- query prints all 16 entries and records PATCH; query ABI 80-B/5136.

Hardware state after the external-VAS run: GPU wedged, reboot required (no
automated reboot). All shapes stay default-off behind gr_promote=17 +
gsp_phys_srv_ctxbuf.

1 files changed, 19 insertions, 0 deletions

diff --git a/kernel/gsp_phys_gpu.c b/kernel/gsp_phys_gpu.c
index 91f7a77..94d6652 100644
--- a/kernel/gsp_phys_gpu.c
+++ b/kernel/gsp_phys_gpu.c
@@ -182,6 +182,25 @@ bool gsp_phys_srv_ctxbuf_value(void)
 EXPORT_SYMBOL_GPL(gsp_phys_srv_ctxbuf_value);
 
 /*
+ * Server-managed GR context client commit (default 1). On the
+ * gsp_phys_srv_ctxbuf path the ladder sends GPU_INITIALIZE_CTX + a PA-only
+ * GPU_PROMOTE_CTX for the server-reported MAIN context buffer. Set 0 to test
+ * the pure server-managed shape: the GSP-RM allocated/mapped/committed the
+ * context itself and no client control is sent.
+ */
+static bool gsp_phys_srv_ctxcommit_param = true;
+module_param_named(gsp_phys_rmcall_srv_ctxcommit, gsp_phys_srv_ctxcommit_param,
+		   bool, 0644);
+MODULE_PARM_DESC(gsp_phys_rmcall_srv_ctxcommit,
+		 "On the server-managed GR ctx path send GPU_INITIALIZE_CTX + PA-only GPU_PROMOTE_CTX for the server MAIN (default 1); 0 = pure server-managed, no client promote");
+
+bool gsp_phys_srv_ctxcommit_value(void)
+{
+	return gsp_phys_srv_ctxcommit_param;
+}
+EXPORT_SYMBOL_GPL(gsp_phys_srv_ctxcommit_value);
+
+/*
  * P5 wave-1 shadow work forwarding (default 0). When set, the sema service
  * requests one real CE copy on the debugfs ladder's channel for each decoded
  * guest CE push, using only the ladder's module-owned buffers; the software