drm/nouveau/fifo/ga100-: remove individual runlists rather than failing oneinit

We're adding better support for the non-stall interrupt, which will need
to fetch the interrupt vector from the runlist's primary engine.

NVKM doesn't support all target engines (ie. NVDEC etc), and it wouldn't
be ideal to completely fail initialisation in this case.

Instead.  Remove runlists where we can't determine all the needed info.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230525003106.3853741-7-skeggsb@gmail.com

drivers/gpu/drm/nouveau/nvkm/engine/fifo/ga100.c

@@ -429,7 +429,9 @@ static int
 ga100_runl_new(struct nvkm_fifo *fifo, int id, u32 addr, struct nvkm_runl **prunl)
 {
 	struct nvkm_device *device = fifo->engine.subdev.device;
+	struct nvkm_top_device *tdev;
 	struct nvkm_runl *runl;
+	struct nvkm_engn *engn;
 	u32 chcfg  = nvkm_rd32(device, addr + 0x004);
 	u32 chnum  = 1 << (chcfg & 0x0000000f);
 	u32 chaddr = (chcfg & 0xfffffff0);
@@ -437,26 +439,50 @@ ga100_runl_new(struct nvkm_fifo *fifo, int id, u32 addr, struct nvkm_runl **prun
 	u32 vector = nvkm_rd32(device, addr + 0x160);
 	int i, ret;
 
-	runl = *prunl = nvkm_runl_new(fifo, id, addr, chnum);
+	runl = nvkm_runl_new(fifo, id, addr, chnum);
 	if (IS_ERR(runl))
 		return PTR_ERR(runl);
 
+	*prunl = runl;
+
 	for (i = 0; i < 2; i++) {
 		u32 pbcfg = nvkm_rd32(device, addr + 0x010 + (i * 0x04));
 		if (pbcfg & 0x80000000) {
 			runl->runq[runl->runq_nr] =
 				nvkm_runq_new(fifo, ((pbcfg & 0x03fffc00) - 0x040000) / 0x800);
-			if (!runl->runq[runl->runq_nr])
+			if (!runl->runq[runl->runq_nr]) {
+				RUNL_ERROR(runl, "runq %d", runl->runq_nr);
 				return -ENOMEM;
+			}
 
 			runl->runq_nr++;
 		}
 	}
 
+	nvkm_list_foreach(tdev, &device->top->device, head, tdev->runlist == runl->addr) {
+		if (tdev->engine < 0) {
+			RUNL_DEBUG(runl, "engn !top");
+			return -EINVAL;
+		}
+
+		engn = nvkm_runl_add(runl, tdev->engine, (tdev->type == NVKM_ENGINE_CE) ?
+				     fifo->func->engn_ce : fifo->func->engn,
+				     tdev->type, tdev->inst);
+		if (!engn)
+			return -EINVAL;
+	}
+
+	if (list_empty(&runl->engns)) {
+		RUNL_DEBUG(runl, "!engns");
+		return -EINVAL;
+	}
+
 	ret = nvkm_inth_add(&device->vfn->intr, vector & 0x00000fff, NVKM_INTR_PRIO_NORMAL,
 			    &fifo->engine.subdev, ga100_runl_intr, &runl->inth);
-	if (ret)
+	if (ret) {
+		RUNL_ERROR(runl, "inth %d", ret);
 		return ret;
+	}
 
 	runl->chan = chaddr;
 	runl->doorbell = dbcfg >> 16;
@@ -514,15 +540,13 @@ ga100_fifo_runl_ctor(struct nvkm_fifo *fifo)
 		runl = nvkm_runl_get(fifo, -1, tdev->runlist);
 		if (!runl) {
 			ret = ga100_runl_new(fifo, id++, tdev->runlist, &runl);
-			if (ret)
-				return ret;
-		}
-
-		if (tdev->engine < 0)
-			continue;
+			if (ret) {
+				if (runl)
+					nvkm_runl_del(runl);
 
-		nvkm_runl_add(runl, tdev->engine, (tdev->type == NVKM_ENGINE_CE) ?
-			      fifo->func->engn_ce : fifo->func->engn, tdev->type, tdev->inst);
+				continue;
+			}
+		}
 	}
 
 	return 0;