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  1. 06 12月, 2011 8 次提交
    • K
      drm/ttm: provide dma aware ttm page pool code V9 · 2334b75f
      由 Konrad Rzeszutek Wilk 提交于 
      In TTM world the pages for the graphic drivers are kept in three different
pools: write combined, uncached, and cached (write-back). When the pages
are used by the graphic driver the graphic adapter via its built in MMU
(or AGP) programs these pages in. The programming requires the virtual address
(from the graphic adapter perspective) and the physical address (either System RAM
or the memory on the card) which is obtained using the pci_map_* calls (which does the
virtual to physical - or bus address translation). During the graphic application's
"life" those pages can be shuffled around, swapped out to disk, moved from the
VRAM to System RAM or vice-versa. This all works with the existing TTM pool code
- except when we want to use the software IOTLB (SWIOTLB) code to "map" the physical
addresses to the graphic adapter MMU. We end up programming the bounce buffer's
physical address instead of the TTM pool memory's and get a non-worky driver.
There are two solutions:
1) using the DMA API to allocate pages that are screened by the DMA API, or
2) using the pci_sync_* calls to copy the pages from the bounce-buffer and back.

This patch fixes the issue by allocating pages using the DMA API. The second
is a viable option - but it has performance drawbacks and potential correctness
issues - think of the write cache page being bounced (SWIOTLB->TTM), the
WC is set on the TTM page and the copy from SWIOTLB not making it to the TTM
page until the page has been recycled in the pool (and used by another application).

The bounce buffer does not get activated often - only in cases where we have
a 32-bit capable card and we want to use a page that is allocated above the
4GB limit. The bounce buffer offers the solution of copying the contents
of that 4GB page to an location below 4GB and then back when the operation has been
completed (or vice-versa). This is done by using the 'pci_sync_*' calls.
Note: If you look carefully enough in the existing TTM page pool code you will
notice the GFP_DMA32 flag is used  - which should guarantee that the provided page
is under 4GB. It certainly is the case, except this gets ignored in two cases:
 - If user specifies 'swiotlb=force' which bounces _every_ page.
 - If user is using a Xen's PV Linux guest (which uses the SWIOTLB and the
   underlaying PFN's aren't necessarily under 4GB).

To not have this extra copying done the other option is to allocate the pages
using the DMA API so that there is not need to map the page and perform the
expensive 'pci_sync_*' calls.

This DMA API capable TTM pool requires for this the 'struct device' to
properly call the DMA API. It also has to track the virtual and bus address of
the page being handed out in case it ends up being swapped out or de-allocated -
to make sure it is de-allocated using the proper's 'struct device'.

Implementation wise the code keeps two lists: one that is attached to the
'struct device' (via the dev->dma_pools list) and a global one to be used when
the 'struct device' is unavailable (think shrinker code). The global list can
iterate over all of the 'struct device' and its associated dma_pool. The list
in dev->dma_pools can only iterate the device's dma_pool.
                                                            /[struct device_pool]\
        /---------------------------------------------------| dev                |
       /                                            +-------| dma_pool           |
 /-----+------\                                    /        \--------------------/
 |struct device|     /-->[struct dma_pool for WC]</         /[struct device_pool]\
 | dma_pools   +----+                                     /-| dev                |
 |  ...        |    \--->[struct dma_pool for uncached]<-/--| dma_pool           |
 \-----+------/                                         /   \--------------------/
        \----------------------------------------------/
[Two pools associated with the device (WC and UC), and the parallel list
containing the 'struct dev' and 'struct dma_pool' entries]

The maximum amount of dma pools a device can have is six: write-combined,
uncached, and cached; then there are the DMA32 variants which are:
write-combined dma32, uncached dma32, and cached dma32.

Currently this code only gets activated when any variant of the SWIOTLB IOMMU
code is running (Intel without VT-d, AMD without GART, IBM Calgary and Xen PV
with PCI devices).
Tested-by: NMichel Dänzer <michel@daenzer.net>
[v1: Using swiotlb_nr_tbl instead of swiotlb_enabled]
[v2: Major overhaul - added 'inuse_list' to seperate used from inuse and reorder
the order of lists to get better performance.]
[v3: Added comments/and some logic based on review, Added Jerome tag]
[v4: rebase on top of ttm_tt & ttm_backend merge]
[v5: rebase on top of ttm memory accounting overhaul]
[v6: New rebase on top of more memory accouting changes]
[v7: well rebase on top of no memory accounting changes]
[v8: make sure pages list is initialized empty]
[v9: calll ttm_mem_global_free_page in unpopulate for accurate accountg]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Acked-by: NThomas Hellstrom <thellstrom@vmware.com>
      2334b75f
    • J
      drm/ttm: introduce callback for ttm_tt populate & unpopulate V4 · b1e5f172
      由 Jerome Glisse 提交于 
      Move the page allocation and freeing to driver callback and
provide ttm code helper function for those.

Most intrusive change, is the fact that we now only fully
populate an object this simplify some of code designed around
the page fault design.

V2 Rebase on top of memory accounting overhaul
V3 New rebase on top of more memory accouting changes
V4 Rebase on top of no memory account changes (where/when is my
   delorean when i need it ?)
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
      b1e5f172
    • J
      drm/ttm: merge ttm_backend and ttm_tt V5 · 649bf3ca
      由 Jerome Glisse 提交于 
      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: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
      649bf3ca
    • J
      drm/ttm: page allocation use page array instead of list · 822c4d9a
      由 Jerome Glisse 提交于 
      Use the ttm_tt pages array for pages allocations, move the list
unwinding into the page allocation functions.
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
      822c4d9a
    • J
      drm/ttm: test for dma_address array allocation failure · f9517e63
      由 Jerome Glisse 提交于 
      Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
      f9517e63
    • J
      drm/ttm: use ttm put pages function to properly restore cache attribute · 5e265680
      由 Jerome Glisse 提交于 
      On failure we need to make sure the page we free has wb cache
attribute. Do this pas call the proper ttm page helper function.
Signed-off-by: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
      5e265680
    • J
      drm/ttm: remove split btw highmen and lowmem page · 667b7a27
      由 Jerome Glisse 提交于 
      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: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
      667b7a27
    • J
      drm/ttm: remove userspace backed ttm object support · 3316497b
      由 Jerome Glisse 提交于 
      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: NJerome Glisse <jglisse@redhat.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
      3316497b
  3. 01 11月, 2011 1 次提交
  5. 28 10月, 2011 1 次提交
  7. 18 10月, 2011 1 次提交
  9. 05 10月, 2011 1 次提交
  11. 14 9月, 2011 1 次提交
  13. 01 9月, 2011 1 次提交
    • M
      drm/ttm: add a way to bo_wait for either the last read or last write · dfadbbdb
      由 Marek Olšák 提交于 
      Sometimes we want to know whether a buffer is busy and wait for it (bo_wait).
However, sometimes it would be more useful to be able to query whether
a buffer is busy and being either read or written, and wait until it's stopped
being either read or written. The point of this is to be able to avoid
unnecessary waiting, e.g. if a GPU has written something to a buffer and is now
reading that buffer, and a CPU wants to map that buffer for read, it needs to
only wait for the last write. If there were no write, there wouldn't be any
waiting needed.

This, or course, requires user space drivers to send read/write flags
with each relocation (like we have read/write domains in radeon, so we can
actually use those for something useful now).

Now how this patch works:

The read/write flags should passed to ttm_validate_buffer. TTM maintains
separate sync objects of the last read and write for each buffer, in addition
to the sync object of the last use of a buffer. ttm_bo_wait then operates
with one the sync objects.
Signed-off-by: NMarek Olšák <maraeo@gmail.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>
      dfadbbdb
  15. 23 8月, 2011 3 次提交
  17. 27 7月, 2011 1 次提交
  19. 28 6月, 2011 1 次提交
  21. 21 6月, 2011 1 次提交
  23. 25 5月, 2011 1 次提交
  25. 13 4月, 2011 1 次提交
  27. 10 4月, 2011 1 次提交
  29. 05 4月, 2011 1 次提交
  31. 23 2月, 2011 3 次提交
  33. 28 1月, 2011 3 次提交
  35. 24 12月, 2010 1 次提交
    • T
      drm/ttm: use cancel_delayed_work_sync() in ttm_bo · f094cfc6
      由 Tejun Heo 提交于 
      Make ttm_bo::ttm_bo_device_release call cancel_delayed_work_sync()
instead of calling cancel_delayed_work() followed by
flush_scheduled_work().

This is to prepare for the deprecation and removal of
flush_scheduled_work().
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc:: Thomas Hellstrom <thellstrom@vmware.com>
Cc:: Dave Airlie <airlied@redhat.com>
      f094cfc6
  37. 16 12月, 2010 1 次提交
  39. 22 11月, 2010 8 次提交