diff options
| author | Lauri Kasanen <cand@gmx.com> | 2014-04-02 20:03:57 +0300 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2014-04-04 09:28:14 +1000 |
| commit | 62347f9e0f81d50e9b0923ec8a192f60ab7a1801 (patch) | |
| tree | b7d6db268abfe08ff52742a47902474877bfa0a4 /include/drm/ttm | |
| parent | 2614dc66837c2a6fd0e14e3f8e72343782c8b784 (diff) | |
drm: Add support for two-ended allocation, v3
Clients like i915 need to segregate cache domains within the GTT which
can lead to small amounts of fragmentation. By allocating the uncached
buffers from the bottom and the cacheable buffers from the top, we can
reduce the amount of wasted space and also optimize allocation of the
mappable portion of the GTT to only those buffers that require CPU
access through the GTT.
For other drivers, allocating small bos from one end and large ones
from the other helps improve the quality of fragmentation.
Based on drm_mm work by Chris Wilson.
v3: Changed to use a TTM placement flag
v2: Updated kerneldoc
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Christian König <deathsimple@vodafone.de>
Signed-off-by: Lauri Kasanen <cand@gmx.com>
Signed-off-by: David Airlie <airlied@redhat.com>
Diffstat (limited to 'include/drm/ttm')
| -rw-r--r-- | include/drm/ttm/ttm_placement.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/drm/ttm/ttm_placement.h b/include/drm/ttm/ttm_placement.h index c84ff153a564..8ed44f9bbdfb 100644 --- a/include/drm/ttm/ttm_placement.h +++ b/include/drm/ttm/ttm_placement.h @@ -65,6 +65,8 @@ * reference the buffer. * TTM_PL_FLAG_NO_EVICT means that the buffer may never * be evicted to make room for other buffers. + * TTM_PL_FLAG_TOPDOWN requests to be placed from the + * top of the memory area, instead of the bottom. */ #define TTM_PL_FLAG_CACHED (1 << 16) @@ -72,6 +74,7 @@ #define TTM_PL_FLAG_WC (1 << 18) #define TTM_PL_FLAG_SHARED (1 << 20) #define TTM_PL_FLAG_NO_EVICT (1 << 21) +#define TTM_PL_FLAG_TOPDOWN (1 << 22) #define TTM_PL_MASK_CACHING (TTM_PL_FLAG_CACHED | \ TTM_PL_FLAG_UNCACHED | \ |