ttm_backend will only exist with a ttm_tt, and ttm_tt
will only be of interest when bound to a backend. Merge them
to avoid code and data duplication.
V2 Rebase on top of memory accounting overhaul
V3 Rebase on top of more memory accounting changes
V4 Rebase on top of no memory account changes (where/when is my
delorean when i need it ?)
V5 make sure ttm is unbound before destroying, change commit
message on suggestion from Tormod Volden
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Use the ttm_tt pages array for pages allocations, move the list
unwinding into the page allocation functions.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
This field is not use by any of the driver just drop it.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Split btw highmem and lowmem page was rendered useless by the
pool code. Remove it. Note further cleanup would change the
ttm page allocation helper to actualy take an array instead
of relying on list this could drasticly reduce the number of
function call in the common case of allocation whole buffer.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
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>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
. 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>
This reverts commit 5a893fc28f.
This causes a use after free in the ttm free alloc pages path,
when it tries to get the be after the be has been destroyed.
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'stable/ttm.pci-api.v5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
ttm: Include the 'struct dev' when using the DMA API.
nouveau/ttm/PCIe: Use dma_addr if TTM has set it.
radeon/ttm/PCIe: Use dma_addr if TTM has set it.
ttm: Expand (*populate) to support an array of DMA addresses.
ttm: Utilize the DMA API for pages that have TTM_PAGE_FLAG_DMA32 set.
ttm: Introduce a placeholder for DMA (bus) addresses.
This makes the accounting when using 'debug_dma_dump_mappings()'
and CONFIG_DMA_API_DEBUG=y be assigned to the correct device
instead of 'fallback'.
No functional change - just cosmetic.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We pass in the array of ttm pages to be populated in the GART/MM
of the card (or AGP). Patch titled: "ttm: Utilize the DMA API for
pages that have TTM_PAGE_FLAG_DMA32 set." uses the DMA API to make
those pages have a proper DMA addresses (in the situation where
page_to_phys or virt_to_phys do not give use the DMA (bus) address).
Since we are using the DMA API on those pages, we should pass in the
DMA address to this function so it can save it in its proper fields
(later patches use it).
[v2: Added reviewed-by tag]
Reviewed-by: Thomas Hellstrom <thellstrom@shipmail.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Ian Campbell <ian.campbell@citrix.com>
This is right now limited to only non-pool constructs.
[v2: Fixed indentation issues, add review-by tag]
Reviewed-by: Thomas Hellstrom <thomas@shipmail.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Ian Campbell <ian.campbell@citrix.com>
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>
Rather than having the driver supply the validation sequence, leave that
responsibility to TTM. This saves some confusion and a function argument.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Drastically reduce the number of spin lock / unlock operations by performing
unreserving and fencing under global locks.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jerome Glisse <j.glisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
Add an aid for the driver to detect deadlocks on multi-bo reservations
Update documentation.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jerome Glisse <j.glisse@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
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>
Remove an obsolete comment about mm nodes.
Document the new bo range manager interface.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
We need the unlocked variant for the new codepath introduced to fix the
race condition in master recently.
Signed-off-by: Dave Airlie <airlied@redhat.com>
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=615505http://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>
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>
Existing core code/drivers call drm_mm_put_block on ttm_mem_reg.mm_node
directly. Future patches will modify TTM behaviour in such a way that
ttm_mem_reg.mm_node doesn't necessarily belong to drm_mm.
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: Thomas Hellström <thellstrom@vmware.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
I wrote this for the prime sharing work, but I also noticed other external
non-upstream drivers from a large company carrying a similiar patch, so I
may as well ship it in master.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Repeated ttm_page_alloc_init/fini fails noisily because the pool
manager kobj isn't zeroed out between uses (we could do just that but
statically allocated kobjects are generally considered a bad thing).
Move it to kzalloc'ed memory.
Note that this patch drops the refcounting behavior of the pool
allocator init/fini functions: it would have led to a race condition
in its current form, and anyway it was never exploited.
This fixes a regression with reloading kms modules at runtime, since
page allocator was introduced.
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'drm-for-2.6.35' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (207 commits)
drm/radeon/kms/pm/r600: select the mid clock mode for single head low profile
drm/radeon: fix power supply kconfig interaction.
drm/radeon/kms: record object that have been list reserved
drm/radeon: AGP memory is only I/O if the aperture can be mapped by the CPU.
drm/radeon/kms: don't default display priority to high on rs4xx
drm/edid: fix typo in 1600x1200@75 mode
drm/nouveau: fix i2c-related init table handlers
drm/nouveau: support init table i2c device identifier 0x81
drm/nouveau: ensure we've parsed i2c table entry for INIT_*I2C* handlers
drm/nouveau: display error message for any failed init table opcode
drm/nouveau: fix init table handlers to return proper error codes
drm/nv50: support fractional feedback divider on newer chips
drm/nv50: fix monitor detection on certain chipsets
drm/nv50: store full dcb i2c entry from vbios
drm/nv50: fix suspend/resume with DP outputs
drm/nv50: output calculated crtc pll when debugging on
drm/nouveau: dump pll limits entries when debugging is on
drm/nouveau: bios parser fixes for eDP boards
drm/nouveau: fix a nouveau_bo dereference after it's been destroyed
drm/nv40: remove some completed ctxprog TODOs
...
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>
It's unused and buggy in its current form, since it can place a bo
in the reserved state without removing it from lru lists.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* drm-ttm-unmappable:
drm/radeon/kms: enable use of unmappable VRAM V2
drm/ttm: remove io_ field from TTM V6
drm/vmwgfx: add support for new TTM fault callback V5
drm/nouveau/kms: add support for new TTM fault callback V5
drm/radeon/kms: add support for new fault callback V7
drm/ttm: ttm_fault callback to allow driver to handle bo placement V6
drm/ttm: split no_wait argument in 2 GPU or reserve wait
Conflicts:
drivers/gpu/drm/nouveau/nouveau_bo.c
All TTM driver have been converted to new io_mem_reserve/free
interface which allow driver to choose and return proper io
base, offset to core TTM for ioremapping if necessary. This
patch remove what is now deadcode.
V2 adapt to match with change in first patch of the patchset
V3 update after io_mem_reserve/io_mem_free callback balancing
V4 adjust to minor cleanup
V5 remove the needs ioremap flag
V6 keep the ioremapping facility in TTM
[airlied- squashed driver removals in here also]
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
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>
Sysfs interface allows user to configure pool allocator functionality and
change limits for the size of pool.
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
ttm_page_alloc_debugfs can be registered to output the state
of pools.
Debugfs file will output number of pages freed from the pool,
number of pages in pool now and the lowes number of pages in
pool since previous shrink.
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
On AGP system we might allocate/free routinely uncached or wc memory,
changing page from cached (wb) to uc or wc is very expensive and involves
a lot of flushing. To improve performance this allocator use a pool
of uc,wc pages.
Pools are protected with spinlocks to allow multiple threads to allocate pages
simultanously. Expensive operations are done outside of spinlock to maximize
concurrency.
Pools are linked lists of pages that were recently freed. mm shrink callback
allows kernel to claim back pages when they are required for something else.
Fixes:
* set_pages_array_wb handles highmem pages so we don't have to remove them
from pool.
* Add count parameter to ttm_put_pages to avoid looping in free code.
* Change looping from _safe to normal in pool fill error path.
* Initialize sum variable and make the loop prettier in get_num_unused_pages.
* Moved pages_freed reseting inside the loop in ttm_page_pool_free.
* Add warning comment about spinlock context in ttm_page_pool_free.
Based on Jerome Glisse's and Dave Airlie's pool allocator.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Pauli Nieminen <suokkos@gmail.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Now that the drm core can do this, lets just use it, split the code out
so TTM doesn't have to drag all of drmP.h in.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fix function prototype to match its actual usage and implementation.
drivers/gpu/drm/ttm/ttm_bo_util.c:341:10: error: symbol 'ttm_io_prot' redeclared with different type (originally declared at include/drm/ttm/ttm_bo_driver.h:911) - incompatible argument 1 (different signedness)
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This is needed for a bugfix in the vmwgfx driver.
Drivers may have GPU bindings on buffers that core TTM is not aware of,
and TTM may view those buffers as ordinary system memory buffers.
Add a notifier to such drivers when TTM is about to move the buffer
contents out to swappable memory. The driver must then release any
private GPU bindings on those buffers.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
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>
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>
Utilities to reserve, unreserve and fence a list of TTM
buffer objects in a deadlock-safe manner.
Used by the vmwgfx driver.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This is intended to be used by ttm-aware drivers to
1) Block clients to inactive masters when
they try to validate buffers for GPU use.
2) Optionally block clients to the current master when
there is thrashing due to GPU memory shortage.
Used by the vmwgfx driver.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Add objects needed for user-space to maintain reference counts on ttm objects.
This is used by the vmwgfx driver which allows user-space to maintain
map-counts on dma buffers, lock-counts on the ttm lock and ref-counts on
gpu surfaces, gpu contexts and dma buffer.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
drm/ttm fails to build on MIPS because "struct page" is not known:
| In file included from drivers/gpu/drm/ttm/ttm_memory.c:28:
| include/drm/ttm/ttm_memory.h:154: warning: 'struct page' declared inside parameter list
| include/drm/ttm/ttm_memory.h:154: warning: its scope is only this definition or declaration, which is probably not what you want
| include/drm/ttm/ttm_memory.h:156: warning: 'struct page' declared inside parameter list
| drivers/gpu/drm/ttm/ttm_memory.c:540: error: conflicting types for 'ttm_mem_global_alloc_page'
| include/drm/ttm/ttm_memory.h:154: error: previous declaration of 'ttm_mem_global_alloc_page' was here
| drivers/gpu/drm/ttm/ttm_memory.c:561: error: conflicting types for 'ttm_mem_global_free_page'
| include/drm/ttm/ttm_memory.h:156: error: previous declaration of 'ttm_mem_global_free_page' was here
Signed-off-by: Martin Michlmayr <tbm@cyrius.com>
Cc: stable@kernel.org
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
Use inclusive zones to simplify accounting and its sysfs representation.
Use DMA32 accounting where applicable.
Add a sysfs interface to make the heuristically determined limits
readable and configurable.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
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>
This adds new set/get tiling interfaces where the pitch
and macro/micro tiling enables can be set. Along with
a flag to decide if this object should have a surface when mapped.
The only thing we need to allocate with a mapped surface should be
the frontbuffer. Note rotate scanout shouldn't require one, and
back/depth shouldn't either, though mesa needs some fixes.
It fixes the TTM interfaces along Thomas's suggestions, and I've tested
the surface stealing code with two X servers and not seen any lockdep issues.
I've stopped tiling the fbcon frontbuffer, as I don't see there being
any advantage other than testing, I've left the testing commands in there,
just flip the fb_tiled to true in radeon_fb.c
Open: Can we integrate endian swapping in with this?
Future features:
texture tiling - need to relocate texture registers TXOFFSET* with tiling info.
This also merges Michel's cleanup surfaces regs at init time patch
even though it makes sense on its own, this patch really relies on it.
Some PowerMac firmwares set up a tiling surface at the beginning of VRAM
which messes us up otherwise.
that patch is:
Signed-off-by: Michel Dänzer <daenzer@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This add support for using dma32 memory on gpus that really need it.
Currently IGPs are left without DMA32 but we might need to change
that unless we can fix rs690.
Signed-off-by: Dave Airlie <airlied@redhat.com>
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>
