From 69b136f200006ee37b039195eaeb08942c419ecc Mon Sep 17 00:00:00 2001 From: Ben Skeggs Date: Wed, 1 Nov 2017 03:56:19 +1000 Subject: [PATCH] drm/nouveau/imem/nv50: prevent fast-path for mapped objects when BAR isn't ready Another piece of solving the "GP100 BAR2 VMM bootstrap" puzzle. Without doing this, we'd attempt to write PDEs for the lower page table levels through BAR2 before BAR2 access has been fully initialised. Signed-off-by: Ben Skeggs --- drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c b/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c index ec2904a0e9fc..1a254e69fece 100644 --- a/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/nv50.c @@ -196,9 +196,11 @@ nv50_instobj_acquire(struct nvkm_memory *memory) } /* Attempt to get a direct CPU mapping of the object. */ - if (!iobj->map && (vmm = nvkm_bar_bar2_vmm(imem->subdev.device))) - nv50_instobj_kmap(iobj, vmm); - map = iobj->map; + if ((vmm = nvkm_bar_bar2_vmm(imem->subdev.device))) { + if (!iobj->map) + nv50_instobj_kmap(iobj, vmm); + map = iobj->map; + } if (!refcount_inc_not_zero(&iobj->maps)) { if (map) -- 2.30.2