On 10/30/2014 12:29 AM, Ilia Mirkin wrote:
On Mon, Oct 27, 2014 at 6:34 AM, Alexandre Courbot <acourbot@xxxxxxxxxx> wrote:GK20A does not have dedicated VRAM, therefore allocating in VRAM can be sub-optimal and sometimes even harmful. Set its VRAM domain to NOUVEAU_BO_GART so all objects are allocated in system memory. Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx> --- src/gallium/drivers/nouveau/nvc0/nvc0_screen.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c b/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c index ac5823e4a8d5..ad143cd9a140 100644 --- a/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c +++ b/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c @@ -620,6 +620,16 @@ nvc0_screen_create(struct nouveau_device *dev) return NULL; pscreen = &screen->base.base; + /* Recognize chipsets with no VRAM */ + switch (dev->chipset) { + /* GK20A */ + case 0xea: + screen->base.vram_domain = NOUVEAU_BO_GART;I think you also want to set vidmem_bindings = 0... although potentially after the |= that's done below. Although I guess that constbuf + command args buf need to be |='d into the sysmem_bindings for this to work out well. That said, we don't really handle explicit migration well right now, and those PIPE_BIND_* are *incredibly* misleading and don't actually necessarily reflect the current usage. [I have some patches to improve the situation, but you don't really have to worry about that.]
In the light of that it could be that the vram_domain member I am introducing is completely useless - if we set NV_VRAM_DOMAIN to be the following:
#define NV_VRAM_DOMAIN(screen) ((screen)->vidmem_bindings == 0 ? NOUVEAU_BO_GART : NOUVEAU_BO_VRAM)
then I suspect we can just live without it. I tested quickly and it seems to work. Ilia, do you agree? Or could we imagine having GPUs with VRAM for which none of the PIPE_BIND_* targets should reside in VRAM?
Also thinking, prior to setting vidmem_bindings to 0, shouldn't we also do a "sysmem_bindings |= vidmem_bindings" to make sure all the set bindings are tracked somewhere?
-- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
