7 files changed, 57 insertions, 17 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index 860b0e2d4181..8670d90cdc11 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -869,13 +869,20 @@ nouveau_display_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
                             struct drm_mode_create_dumb *args)
 {
         struct nouveau_bo *bo;
+        uint32_t domain;
         int ret;
 
         args->pitch = roundup(args->width * (args->bpp / 8), 256);
         args->size = args->pitch * args->height;
         args->size = roundup(args->size, PAGE_SIZE);
 
-        ret = nouveau_gem_new(dev, args->size, 0, NOUVEAU_GEM_DOMAIN_VRAM, 0, 0, &bo);
+        /* Use VRAM if there is any ; otherwise fallback to system memory */
+        if (nouveau_drm(dev)->device.info.ram_size != 0)
+                domain = NOUVEAU_GEM_DOMAIN_VRAM;
+        else
+                domain = NOUVEAU_GEM_DOMAIN_GART;
+
+        ret = nouveau_gem_new(dev, args->size, 0, domain, 0, 0, &bo);
         if (ret)
                 return ret;
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c b/drivers/gpu/drm/nouveau/nouveau_ttm.c
index 273e50110ec3..18f449715788 100644
--- a/drivers/gpu/drm/nouveau/nouveau_ttm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c
@@ -82,6 +82,9 @@ nouveau_vram_manager_new(struct ttm_mem_type_manager *man,
         u32 size_nc = 0;
         int ret;
 
+        if (drm->device.info.ram_size == 0)
+                return -ENOMEM;
+
         if (nvbo->tile_flags & NOUVEAU_GEM_TILE_NONCONTIG)
                 size_nc = 1 << nvbo->page_shift;
 
diff --git a/drivers/gpu/drm/nouveau/nv84_fence.c b/drivers/gpu/drm/nouveau/nv84_fence.c
index bf429cabbaa8..a03db4368696 100644
--- a/drivers/gpu/drm/nouveau/nv84_fence.c
+++ b/drivers/gpu/drm/nouveau/nv84_fence.c
@@ -215,6 +215,7 @@ nv84_fence_create(struct nouveau_drm *drm)
 {
         struct nvkm_fifo *pfifo = nvxx_fifo(&drm->device);
         struct nv84_fence_priv *priv;
+        u32 domain;
         int ret;
 
         priv = drm->fence = kzalloc(sizeof(*priv), GFP_KERNEL);
@@ -231,10 +232,17 @@ nv84_fence_create(struct nouveau_drm *drm)
         priv->base.context_base = fence_context_alloc(priv->base.contexts);
         priv->base.uevent = true;
 
-        ret = nouveau_bo_new(drm->dev, 16 * priv->base.contexts, 0,
-                             TTM_PL_FLAG_VRAM, 0, 0, NULL, NULL, &priv->bo);
+        /* Use VRAM if there is any ; otherwise fallback to system memory */
+        domain = drm->device.info.ram_size != 0 ? TTM_PL_FLAG_VRAM :
+                         /*
+                          * fences created in sysmem must be non-cached or we
+                          * will lose CPU/GPU coherency!
+                          */
+                         TTM_PL_FLAG_TT | TTM_PL_FLAG_UNCACHED;
+        ret = nouveau_bo_new(drm->dev, 16 * priv->base.contexts, 0, domain, 0,
+                             0, NULL, NULL, &priv->bo);
         if (ret == 0) {
-                ret = nouveau_bo_pin(priv->bo, TTM_PL_FLAG_VRAM, false);
+                ret = nouveau_bo_pin(priv->bo, domain, false);
                 if (ret == 0) {
                         ret = nouveau_bo_map(priv->bo);
                         if (ret)
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/device/base.c b/drivers/gpu/drm/nouveau/nvkm/engine/device/base.c
index 6efa8f38ff54..63d8e52f4b22 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/device/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/device/base.c
@@ -139,9 +139,13 @@ nvkm_devobj_info(struct nvkm_object *object, void *data, u32 size)
 
         args->v0.chipset  = device->chipset;
         args->v0.revision = device->chiprev;
-        if (pfb)  args->v0.ram_size = args->v0.ram_user = pfb->ram->size;
-        else      args->v0.ram_size = args->v0.ram_user = 0;
-        if (imem) args->v0.ram_user = args->v0.ram_user - imem->reserved;
+        if (pfb && pfb->ram)
+                args->v0.ram_size = args->v0.ram_user = pfb->ram->size;
+        else
+                args->v0.ram_size = args->v0.ram_user = 0;
+        if (imem && args->v0.ram_size > 0)
+                args->v0.ram_user = args->v0.ram_user - imem->reserved;
+
         return 0;
 }
 
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c
index b24a9cc04b73..39a83d82e0cd 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c
@@ -184,7 +184,7 @@ nvkm_pstate_prog(struct nvkm_clk *clk, int pstatei)
         nv_debug(clk, "setting performance state %d\n", pstatei);
         clk->pstate = pstatei;
 
-        if (pfb->ram->calc) {
+        if (pfb->ram && pfb->ram->calc) {
                 int khz = pstate->base.domain[nv_clk_src_mem];
                 do {
                         ret = pfb->ram->calc(pfb, khz);
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/fb/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/fb/base.c
index 16589fa613cd..61fde43dab71 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/fb/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/fb/base.c
@@ -55,9 +55,11 @@ _nvkm_fb_fini(struct nvkm_object *object, bool suspend)
         struct nvkm_fb *pfb = (void *)object;
         int ret;
 
-        ret = nv_ofuncs(pfb->ram)->fini(nv_object(pfb->ram), suspend);
-        if (ret && suspend)
-                return ret;
+        if (pfb->ram) {
+                ret = nv_ofuncs(pfb->ram)->fini(nv_object(pfb->ram), suspend);
+                if (ret && suspend)
+                        return ret;
+        }
 
         return nvkm_subdev_fini(&pfb->base, suspend);
 }
@@ -72,9 +74,11 @@ _nvkm_fb_init(struct nvkm_object *object)
         if (ret)
                 return ret;
 
-        ret = nv_ofuncs(pfb->ram)->init(nv_object(pfb->ram));
-        if (ret)
-                return ret;
+        if (pfb->ram) {
+                ret = nv_ofuncs(pfb->ram)->init(nv_object(pfb->ram));
+                if (ret)
+                        return ret;
+        }
 
         for (i = 0; i < pfb->tile.regions; i++)
                 pfb->tile.prog(pfb, i, &pfb->tile.region[i]);
@@ -91,9 +95,12 @@ _nvkm_fb_dtor(struct nvkm_object *object)
         for (i = 0; i < pfb->tile.regions; i++)
                 pfb->tile.fini(pfb, i, &pfb->tile.region[i]);
         nvkm_mm_fini(&pfb->tags);
-        nvkm_mm_fini(&pfb->vram);
 
-        nvkm_object_ref(NULL, (struct nvkm_object **)&pfb->ram);
+        if (pfb->ram) {
+                nvkm_mm_fini(&pfb->vram);
+                nvkm_object_ref(NULL, (struct nvkm_object **)&pfb->ram);
+        }
+
         nvkm_subdev_destroy(&pfb->base);
 }
 
@@ -127,6 +134,9 @@ nvkm_fb_create_(struct nvkm_object *parent, struct nvkm_object *engine,
 
         pfb->memtype_valid = impl->memtype;
 
+        if (!impl->ram)
+                return 0;
+
         ret = nvkm_object_ctor(nv_object(pfb), NULL, impl->ram, NULL, 0, &ram);
         if (ret) {
                 nv_fatal(pfb, "error detecting memory configuration!!\n");
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gf100.c b/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gf100.c
index 8e7cc6200d60..7fb5ea0314cb 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gf100.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gf100.c
@@ -136,7 +136,8 @@ gf100_ltc_dtor(struct nvkm_object *object)
         struct nvkm_ltc_priv *priv = (void *)object;
 
         nvkm_mm_fini(&priv->tags);
-        nvkm_mm_free(&pfb->vram, &priv->tag_ram);
+        if (pfb->ram)
+                nvkm_mm_free(&pfb->vram, &priv->tag_ram);
 
         nvkm_ltc_destroy(priv);
 }
@@ -149,6 +150,12 @@ gf100_ltc_init_tag_ram(struct nvkm_fb *pfb, struct nvkm_ltc_priv *priv)
         u32 tag_size, tag_margin, tag_align;
         int ret;
 
+        /* No VRAM, no tags for now. */
+        if (!pfb->ram) {
+                priv->num_tags = 0;
+                goto mm_init;
+        }
+
         /* tags for 1/4 of VRAM should be enough (8192/4 per GiB of VRAM) */
         priv->num_tags = (pfb->ram->size >> 17) / 4;
         if (priv->num_tags > (1 << 17))
@@ -183,6 +190,7 @@ gf100_ltc_init_tag_ram(struct nvkm_fb *pfb, struct nvkm_ltc_priv *priv)
                 priv->tag_base = tag_base;
         }
 
+mm_init:
         ret = nvkm_mm_init(&priv->tags, 0, priv->num_tags, 1);
         return ret;
 }