Commit Graph

43 Commits

Author SHA1 Message Date
Christian König
8aa6d4fc5f drm/ttm: remove lazy parameter from ttm_bo_wait
Not used any more.

Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2016-05-04 20:21:26 -04:00
Alex Deucher
749b48faaf drm/ttm: use phys_addr_t for ttm_bus_placement
Fixes ttm on platforms like PPC460 where the CPU
is in 32-bit mode, but the physical addresses are
>32 bits.

Extracted from a patch by Hans Verkuil.

Tested-by: Julian Margetson <runaway@candw.ms>
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Julian Margetson <runaway@candw.ms>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2016-04-04 17:00:01 -04:00
Christian König
ab74961810 drm/ttm: add ttm_bo_move_to_lru_tail function v2
This allows the drivers to move a BO to the end of the LRU
without removing and adding it again.

v2: Make it more robust, handle pinned and swapable BOs as well.

Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2016-01-13 12:21:21 -05:00
Alex Deucher
54c4cd68ed drm/ttm: device address space != CPU address space
We need to store device offsets in 64 bit as the device
address space may be larger than the CPU's.

Fixes GPU init failures on radeons with 4GB or more of
vram on 32 bit kernels.  We put vram at the start of the
GPU's address space so the gart aperture starts at 4 GB
causing all GPU addresses in the gart aperture to get
truncated.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=89072

[airlied: fix warning on nouveau build]

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: thellstrom@vmware.com
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-03-05 09:04:39 +10:00
Maarten Lankhorst
f4f4e3e3e9 drm/ttm: add reservation_object as argument to ttm_bo_init
This allows importing reservation objects from dma-bufs.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
2014-09-30 14:04:00 +02:00
Maarten Lankhorst
f2c24b83ae drm/ttm: flip the switch, and convert to dma_fence
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
2014-09-02 16:41:50 +02:00
Maarten Lankhorst
dd7cfd6412 drm/ttm: kill fence_lock
No users are left, kill it off! :D
Conversion to the reservation api is next on the list, after
that the functionality can be restored with rcu.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
2014-09-01 10:16:43 +02:00
Christian König
f1217ed09f drm/ttm: move fpfn and lpfn into each placement v2
This allows us to more fine grained specify where to place the buffer object.

v2: rebased on drm-next, add bochs changes as well

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
2014-08-27 13:16:04 +02:00
Alexandre Courbot
59201052df drm/ttm: fix kerneldoc of ttm_bo_create
The kerneldoc header of ttm_bo_create() was referring to another
(nonexisting) function and had a few obsolete or incorrect arguments.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-05-26 12:54:09 +10:00
Thomas Hellstrom
c58f009e01 drm/ttm: Remove set_need_resched from the ttm fault handler
Addresses
"[BUG] completely bonkers use of set_need_resched + VM_FAULT_NOPAGE".

In the first occurence it was used to try to be nice while releasing the
mmap_sem and retrying the fault to work around a locking inversion.
The second occurence was never used.

There has been some discussion whether we should change the locking order to
mmap_sem -> bo_reserve. This patch doesn't address that issue, and leaves
that locking order undefined. The solution that we release the mmap_sem if
tryreserve fails and wait for the buffer to become unreserved is something
we want in any case, and follows how the core vm system waits for pages
to be come unlocked while releasing the mmap_sem.

The code also outlines what needs to be changed if we want to establish the
locking order as mmap_sem -> bo::reserve.

One slight issue that remains with this code is that the fault handler might
be prone to starvation if another thread countinously reserves the buffer.
IMO that usage pattern is highly unlikely.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2013-11-20 03:46:54 -08:00
David Herrmann
72525b3f33 drm/ttm: convert to unified vma offset manager
Use the new vma-manager infrastructure. This doesn't change any
implementation details as the vma-offset-manager is nearly copied 1-to-1
from TTM.

The vm_lock is moved into the offset manager so we can drop it from TTM.
During lookup, we use the vma locking helpers to take a reference to the
found object.
In all other scenarios, locking stays the same as before. We always
guarantee that drm_vma_offset_remove() is called only during destruction.
Hence, helpers like drm_vma_node_offset_addr() are always safe as long as
the node has a valid offset.

This also drops the addr_space_offset member as it is a copy of vm_start
in vma_node objects. Use the accessor functions instead.

v4:
 - remove vm_lock
 - use drm_vma_offset_lock_lookup() to protect lookup (instead of vm_lock)

Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Martin Peres <martin.peres@labri.fr>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
2013-07-25 20:47:07 +10:00
Maarten Lankhorst
8f262540e6 drm/ttm: get rid of ttm_bo_is_reserved
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28 12:04:15 +10:00
Maarten Lankhorst
5e33840511 drm/ttm: convert to the reservation api
Now that the code is compatible in semantics, flip the switch.
Use ww_mutex instead of the homegrown implementation.

ww_mutex uses -EDEADLK to signal that the caller has to back off,
and -EALREADY to indicate this buffer is already held by the caller.

ttm used -EAGAIN and -EDEADLK for those, respectively. So some changes
were needed to handle this correctly.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28 12:04:01 +10:00
Maarten Lankhorst
ecff665f5e drm/ttm: make ttm reservation calls behave like reservation calls
This commit converts the source of the val_seq counter to
the ww_mutex api. The reservation objects are converted later,
because there is still a lockdep splat in nouveau that has to
resolved first.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28 12:02:20 +10:00
Maarten Lankhorst
97a875cbdf drm/ttm: remove no_wait_reserve, v3
All items on the lru list are always reservable, so this is a stupid
thing to keep. Not only that, it is used in a way which would
guarantee deadlocks if it were ever to be set to block on reserve.

This is a lot of churn, but mostly because of the removal of the
argument which can be nested arbitrarily deeply in many places.

No change of code in this patch except removal of the no_wait_reserve
argument, the previous patch removed the use of no_wait_reserve.

v2:
 - Warn if -EBUSY is returned on reservation, all objects on the list
   should be reservable. Adjusted patch slightly due to conflicts.
v3:
 - Focus on no_wait_reserve removal only.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-12-10 20:21:30 +10:00
Maarten Lankhorst
654aa79259 drm/ttm: alter cpu_writers to return -EBUSY in ttm_execbuf_util reservations
This is similar to other platforms that don't allow command submission
to buffers locked on the cpu.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-20 16:17:35 +10:00
Maarten Lankhorst
5fb4ef0e36 drm/ttm: remove sync_obj_arg member
vmwgfx was its only user and always sets it to the same..

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-By: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-20 16:09:55 +10:00
Marcin Slusarz
0b91c4a1cd drm/ttm: remove ttm_buffer_object->buffer_start
All drivers set it to 0 and nothing uses it.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-20 16:06:19 +10:00
Maarten Lankhorst
a9dbfff1cb drm/ttm: add ttm_bo_is_reserved
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-07 10:44:38 +10:00
David Howells
a1ce39288e UAPI: (Scripted) Convert #include "..." to #include <path/...> in kernel system headers
Convert #include "..." to #include <path/...> in kernel system headers.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-02 18:01:25 +01:00
Dave Airlie
129b78bfca ttm: add prime sharing support to TTM (v2)
This adds the ability for ttm common code to take an SG table
and use it as the backing for a slave TTM object.

The drivers can then populate their GTT tables using the SG object.

v2: make sure to setup VM for sg bos as well.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-05-23 10:46:27 +01:00
Jerome Glisse
57de4ba959 drm/ttm: simplify memory accounting for ttm user v2
Provide helper function to compute the kernel memory size needed
for each buffer object. Move all the accounting inside ttm, simplifying
driver and avoiding code duplication accross them.

v2 fix accounting of ghost object, one would have thought that i
   would have run into the issue since a longtime but it seems
   ghost object are rare when you have plenty of vram ;)

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
2011-12-06 10:40:11 +00:00
Jerome Glisse
3316497bcd drm/ttm: remove userspace backed ttm object support
This was never use in none of the driver, properly using userspace
page for bo would need more code (vma interaction mostly). Removing
this dead code in preparation of ttm_tt & backend merge.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
2011-12-06 10:38:10 +00:00
Konrad Rzeszutek Wilk
0d74f86f37 ttm: Fix spelling mistakes and remove unused #ifdef
. and some comments to make it easier to understand.

Ackedby: Randy Dunlap <randy.dunlap@oracle.com>
[v2: Added some more updates from Randy Dunlap]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-06-21 12:33:18 +10:00
Linus Torvalds
42933bac11 Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6
* 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6:
  Fix common misspellings
2011-04-07 11:14:49 -07:00
Jan Engelhardt
5df23979bc drm: fix "persistant" typo
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-04-05 10:22:23 +10:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Thomas Hellstrom
eba67093f5 drm/ttm: Fix up io_mem_reserve / io_mem_free calling
This patch attempts to fix up shortcomings with the current calling
sequences.

1) There's a fastpath where no locking occurs and only io_mem_reserved is
   called to obtain needed info for mapping. The fastpath is set per
   memory type manager.
2) If the fastpath is disabled, io_mem_reserve and io_mem_free will be exactly
   balanced and not called recursively for the same struct ttm_mem_reg.
3) Optionally the driver can choose to enable a per memory type manager LRU
   eviction mechanism that, when io_mem_reserve returns -EAGAIN will attempt
   to kill user-space mappings of memory in that manager to free up needed
   resources

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-22 13:25:22 +10:00
Thomas Hellstrom
702adba224 drm/ttm/radeon/nouveau: Kill the bo lock in favour of a bo device fence_lock
The bo lock used only to protect the bo sync object members, and since it
is a per bo lock, fencing a buffer list will see a lot of locks and unlocks.
Replace it with a per-device lock that protects the sync object members on
*all* bos. Reading and setting these members will always be very quick, so
the risc of heavy lock contention is microscopic. Note that waiting for
sync objects will always take place outside of this lock.

The bo device fence lock will eventually be replaced with a seqlock /
rcu mechanism so we can determine that a bo is idle under a
rcu / read seqlock.

However this change will allow us to batch fencing and unreserving of
buffers with a minimal amount of locking.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jerome Glisse <j.glisse@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-22 13:25:18 +10:00
Dave Airlie
d6ea88865d drm/ttm: Add a bo list reserve fastpath (v2)
Makes it possible to reserve a list of buffer objects with a single
spin lock / unlock if there is no contention.
Should improve cpu usage on SMP kernels.

v2: Initialize private list members on reserve and don't call
ttm_bo_list_ref_sub() with zero put_count.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-22 13:24:40 +10:00
Thomas Hellstrom
7dfbbdcffe drm/ttm: Be consistent on ttm_bo_init() failures
Call destroy() on _all_ ttm_bo_init() failures, and make sure that
behavior is documented in the function description.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-10 11:52:19 +10:00
Dave Airlie
b7ae5056c9 Merge branch 'drm-fixes' of /home/airlied/kernel/linux-2.6 into drm-core-next
Conflicts:
	drivers/gpu/drm/i915/intel_fb.c
	drivers/gpu/drm/radeon/r600_blit_kms.c
	drivers/gpu/drm/ttm/ttm_bo.c
2010-10-19 09:48:34 +10:00
Thomas Hellstrom
1df6a2ebd7 drm/ttm: Fix two race conditions + fix busy codepaths
This fixes a race pointed out by Dave Airlie where we don't take a buffer
object about to be destroyed off the LRU lists properly. It also fixes a rare
case where a buffer object could be destroyed in the middle of an
accelerated eviction.

The patch also adds a utility function that can be used to prematurely
release GPU memory space usage of an object waiting to be destroyed.
For example during eviction or swapout.

The above mentioned commit didn't queue the buffer on the delayed destroy
list under some rare circumstances. It also didn't completely honor the
remove_all parameter.

Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=615505
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=591061

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06 09:04:43 +10:00
Ben Skeggs
d961db75ce drm/ttm: restructure to allow driver to plug in alternate memory manager
Nouveau will need this on GeForce 8 and up to account for the GPU
reordering physical VRAM for some memory types.

Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: Thomas Hellström <thellstrom@vmware.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2010-10-05 10:01:20 +10:00
Matthew Garrett
7c5ee5366f ttm: Provide an API for starting and stopping the delayed workqueue
We want to be able to prevent the delayed workqueue from changing state
while we're reclocking, so add an API to block and unblock it.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-05-18 18:21:20 +10:00
Jerome Glisse
82c5da6bf8 drm/ttm: ttm_fault callback to allow driver to handle bo placement V6
On fault the driver is given the opportunity to perform any operation
it sees fit in order to place the buffer into a CPU visible area of
memory. This patch doesn't break TTM users, nouveau, vmwgfx and radeon
should keep working properly. Future patch will take advantage of this
infrastructure and remove the old path from TTM once driver are
converted.

V2 return VM_FAULT_NOPAGE if callback return -EBUSY or -ERESTARTSYS
V3 balance io_mem_reserve and io_mem_free call, fault_reserve_notify
   is responsible to perform any necessary task for mapping to succeed
V4 minor cleanup, atomic_t -> bool as member is protected by reserve
   mecanism from concurent access
V5 the callback is now responsible for iomapping the bo and providing
   a virtual address this simplify TTM and will allow to get rid of
   TTM_MEMTYPE_FLAG_NEEDS_IOREMAP
V6 use the bus addr data to decide to ioremap or this isn't needed
   but we don't necesarily need to ioremap in the callback but still
   allow driver to use static mapping

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-04-20 14:12:05 +10:00
Jerome Glisse
9d87fa2138 drm/ttm: split no_wait argument in 2 GPU or reserve wait
There is case where we want to be able to wait only for the
GPU while not waiting for other buffer to be unreserved. This
patch split the no_wait argument all the way down in the whole
ttm path so that upper level can decide on what to wait on or
not.

[airlied: squashed these 4 for bisectability reasons.]
drm/radeon/kms: update to TTM no_wait splitted argument
drm/nouveau: update to TTM no_wait splitted argument
drm/vmwgfx: update to TTM no_wait splitted argument
[vmwgfx patch: Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>]

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-04-08 10:21:19 +10:00
Jerome Glisse
09855acb1c drm/ttm: Convert ttm_buffer_object_init to use ttm_placement
Convert ttm_buffer_object_init to use struct ttm_placement and
rename to ttm_bo_init for consistency with function naming. This
allow to give more complex placement at buffer creation. For
instance you ask to allocate bo into vram first but if there is
not enough vram you can give system as a second possible
placement. It also allow to create buffer in a specific range.

Also rename ttm_buffer_object_validate to ttm_bo_validate.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2009-12-11 14:09:05 +10:00
Thomas Hellstrom
98ffc4158e drm/ttm: Have the TTM code return -ERESTARTSYS instead of -ERESTART.
Return -ERESTARTSYS instead of -ERESTART when interrupted by a signal.
The -ERESTARTSYS is converted to an -EINTR by the kernel signal layer
before returned to user-space.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2009-12-10 15:09:03 +10:00
Jerome Glisse
ca262a9998 drm/ttm: Rework validation & memory space allocation (V3)
This change allow driver to pass sorted memory placement,
from most prefered placement to least prefered placement.
In order to avoid long function prototype a structure is
used to gather memory placement informations such as range
restriction (if you need a buffer to be in given range).
Range restriction is determined by fpfn & lpfn which are
the first page and last page number btw which allocation
can happen. If those fields are set to 0 ttm will assume
buffer can be put anywhere in the address space (thus it
avoids putting a burden on the driver to always properly
set those fields).

This patch also factor few functions like evicting first
entry of lru list or getting a memory space. This avoid
code duplication.

V2: Change API to use placement flags and array instead
    of packing placement order into a quadword.
V3: Make sure we set the appropriate mem.placement flag
    when validating or allocation memory space.

[Pending Thomas Hellstrom further review but okay
from preliminary review so far].

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2009-12-10 15:09:02 +10:00
Thomas Hellstrom
a987fcaa80 ttm: Make parts of a struct ttm_bo_device global.
Common resources, like memory accounting and swap lists should be
global and not per device. Introduce a struct ttm_bo_global to
accomodate this, and register it with sysfs. Add a small sysfs interface
to return the number of active buffer objects.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
2009-08-19 16:10:34 +10:00
Pekka Paalanen
a0724fcf82 drm/ttm: optimize bo_kmap_type values
A micro-optimization on the function ttm_kmap_obj_virtual().

By defining the values of enum ttm_bo_kmap_obj::bo_kmap_type to have a
bit indicating iomem, size of the function ttm_kmap_obj_virtual() will be
reduced by 16 bytes on x86_64 (gcc 4.1.2).

ttm_kmap_obj_virtual() may be heavily used, when buffer objects are
accessed via wrappers, that work for both kinds of memory addresses:
iomem cookies and kernel virtual.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2009-08-19 16:07:00 +10:00
Thomas Hellstrom
ba4e7d973d drm: Add the TTM GPU memory manager subsystem.
TTM is a GPU memory manager subsystem designed for use with GPU
devices with various memory types (On-card VRAM, AGP,
PCI apertures etc.). It's essentially a helper library that assists
the DRM driver in creating and managing persistent buffer objects.

TTM manages placement of data and CPU map setup and teardown on
data movement. It can also optionally manage synchronization of
data on a per-buffer-object level.

TTM takes care to provide an always valid virtual user-space address
to a buffer object which makes user-space sub-allocation of
big buffer objects feasible.

TTM uses a fine-grained per buffer-object locking scheme, taking
care to release all relevant locks when waiting for the GPU.
Although this implies some locking overhead, it's probably a big
win for devices with multiple command submission mechanisms, since
the lock contention will be minimal.

TTM can be used with whatever user-space interface the driver
chooses, including GEM. It's used by the upcoming Radeon KMS DRM driver
and is also the GPU memory management core of various new experimental
DRM drivers.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2009-06-15 09:37:57 +10:00