Otherwise a pde_shift big enough to overflow a u32 will be truncated before
assignment

Note: We never asked for ranges spanning a 4G boundary, so this issue
doesn't cause a real problem.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
[danvet: Add note why this isn't a real problem.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160217142043.4947.60447.stgit@localhost.localdomain

RC6 setup is shared between BIOS and Driver. BIOS sets up subset of RC6
setup registers. If those are not setup Driver should not enable RC6.
For implementing this, driver can check RC_CTRL0 and RC_CTRL1 values
to know if BIOS has enabled HW/SW RC6.
This will also enable user to control RC6 using BIOS settings alone.
RC6 related instability can be avoided by disabling via BIOS settings
till driver fixes it.

v2: Had placed logic in gen8 function by mistake. Fixed it.
Ensuring RPM is not enabled in case BIOS disabled RC6.

v3: Need to disable RPM if RC6 is disabled due to BIOS settings. (Daniel)
Runtime PM enabling happens before gen9_enable_rc6.
Moved the updation of enable_rc6 parameter in intel_uncore_sanitize.

v4: Added elaborate check for BIOS RC6 setup. Prepared check_pctx for bxt.
    (Imre)

v5: Caching reserved stolen base and size in the driver private data.
    Reorganized RC6 setup check. Moved from gen9_enable_rc6 to
    intel_uncore_sanitize. (Imre)

v6: Rebasing on the patch submitted by Imre that moves gem_init_stolen
    earlier in the load.

v7: Removed PWRCTX_MAXCNT_VCSUNIT1 check as it applies to SKL. (Imre)

v8: Fixed formatting and checkpatch issues. Fixed functional issue where
    RC6 ctx size check was missing. (Imre)

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1454697809-22113-1-git-send-email-sagar.a.kamble@intel.com

Also rename 'rotation_info' to 'rotated' to match the view type exactly,
this should avoid confusion which union members is valid for each view
type.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453316739-13296-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

LRC code was calling GEM API like i915_gem_obj_ggtt_offset from
places where the struct_mutex cannot be grabbed (irq handlers).

To avoid that this patch caches some interesting bits and values
in the engine and context structures.

Some usages are also removed where they are not needed like a
few asserts which are either impossible or have been checked
already during engine initialization.

Side benefit is also that interrupt handlers and command
submission stop evaluating invariant conditionals, like what
Gen we are running on, on every interrupt and every command
submitted.

This patch deals with logical ring context id and descriptors
while subsequent patches will deal with the remaining issues.

v2:
 * Cache the VMA instead of the address. (Chris Wilson)
 * Incorporate Dave Gordon's good comments and function name.

v3:
 * Extract ctx descriptor template to a function and group
   functions dealing with ctx descriptor & co together near
   top of the file. (Dave Gordon)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Gordon <david.s.gordon@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452870629-13830-1-git-send-email-tvrtko.ursulin@linux.intel.com

All of these iterator macros require a 'temp' argument, used merely to
hold internal partial results. We can instead declare the temporary
variable inside the macro, so the caller need not provide it.

Some of the old code contained nested iterators that actually reused the
same 'temp' variable for both inner and outer instances. It's quite
surprising that this didn't introduce bugs! But it does show that the
value of 'temp' isn't required to persist during the iterated body.
Signed-off-by: NDave Gordon <david.s.gordon@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449581451-11848-2-git-send-email-david.s.gordon@intel.com

The rotated view depends upon the rotation paramters, but thus far we
didn't bother checking for those. This seems to have been an issue
ever since this was introduce in

commit fe14d5f4
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Wed Dec 10 17:27:58 2014 +0000

    drm/i915: Infrastructure for supporting different GGTT views per object

But userspace is allowed to reuse framebuffer backing storage with
different framebuffers with different pixel formats/stride/whatever.
And e.g. SNA indeed does this. Hence we must check for all the
paramters to match, not just that it's rotated.

v2: intel_plane_obj_offset also needs to construct the full view, to
avoid fallout since they don't fully match.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-3-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't need 2 separate unions.

Note that this was done intentinoally

Author: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Date:   Wed May 6 14:35:38 2015 +0300

    drm/i915: Add a partial GGTT view type

on Tvrtko's request, but without a clear justification. Rotated views
are also not checking for matching paramters in i915_ggtt_view_equal,
which seems like a bug. But this patch here doesn't change that.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-2-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We tried to fix this in commit fdc454c1 ("drm/i915: Prevent out of
range pt in gen6_for_each_pde").

But the static analyzer still complains that, just before we break due
to "iter < I915_PDES", we do "pt = (pd)->page_table[iter]" with an
iter value that is bigger than I915_PDES. Of course, this isn't really
a problem since no one uses pt outside the macro. Still, every single
new usage of the macro will create a new issue for us to mark as a
false positive.

Also, Paulo re-started the discussion a while ago [1], but didn't end up
implemented.

In order to "solve" this "problem", this patch takes the ideas from
Chris and Dave, but that check would change the desired behavior of the
code, because the object (for example pdp->page_directory[iter]) can be
null during init/alloc, and C would take this as false, breaking the for
loop immediately.

This has been already verified with "static analysis tools".

[1]http://lists.freedesktop.org/archives/intel-gfx/2015-June/068548.html

v2: Make it a single statement, while preventing the common subexpression
elimination (Chris)

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Rebase.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just adding the rotated UV plane at the end of the rotated Y plane.

v2: Rebase.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The FBC hardware for these platforms doesn't have access to the
bios_reserved range, so it always assumes the maximum (8mb) is used.
So avoid this range while allocating.

This solves a bunch of FIFO underruns that happen if you end up
putting the CFB in that memory range. On my machine, with 32mb of
stolen, I need a 2560x1440 mode for that.

Testcase: igt/kms_frontbuffer_tracking/fbc-* (given the right setup)
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to commit c44ef60e ("drm/i915/gtt:
Allow >= 4GB sizes for vm"), i915_gem_obj_offset and i915_gem_obj_ggtt_offset
return an unsigned long, which in only 4-bytes long in 32-bit kernels.

Change return type (and other related offset variables) to u64.

Since Global GTT is always limited to 4GB, this change would not be required
in i915_gem_obj_ggtt_offset, but this is done for consistency.

v2: Remove unnecessary offset variable in do_pin, as we already have
    vma->node.start (Chris).
    Update GGTT offset too (Tvrtko).

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to PDs, while setting up a page directory pointer, make all entries
of the pdp point to the scratch pd before mapping (and make all its entries
point to the scratch page); this is to be safe in case of out of bound
access or  proactive prefetch.

Also add a scratch pdp, which the PML4 entries point to.

v2: Handle scratch_pdp allocation failure correctly, and keep
initialize_px functions together (Akash)
v3: Rebase after Mika's ppgtt cleanup / scratch merge patch series. Rely on
the added macros to initialize the pdps.
v4: Rebase after final merged version of Mika's ppgtt/scratch patches
(and removed commit message part related to v3).
v5: Update commit message to also mention PML4 table initialization and
the new scratch pdp (Akash).
Suggested-by: NAkash Goel <akash.goel@intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NAkash Goel <akash.goel@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

PML4 has no special attributes, and there will always be a PML4.
So simply initialize it at creation, and destroy it at the end.

The code for 4lvl is able to call into the existing 3lvl page table code
to handle all of the lower levels.

v2: Return something at the end of gen8_alloc_va_range_4lvl to keep the
compiler happy. And define ret only in one place.
Updated gen8_ppgtt_unmap_pages and gen8_ppgtt_free to handle 4lvl.
v3: Use i915_dma_unmap_single instead of pci API. Fix a
couple of incorrect checks when unmapping pdp and pd pages (Akash).
v4: Call __pdp_fini also for 32b PPGTT. Clean up alloc_pdp param list.
v5: Prevent (harmless) out of range access in gen8_for_each_pml4e.
v6: Simplify alloc_vma_range_4lvl and gen8_ppgtt_init_common error
paths. (Akash)
v7: Rebase, s/gen8_ppgtt_free_*/gen8_ppgtt_cleanup_*/.
v8: Change location of pml4_init/fini. It will make next patches
cleaner.
v9: Rebase after Mika's ppgtt cleanup / scratch merge patch series, while
trying to reuse as much as possible for pdp alloc. pml4_init/fini
replaced by setup/cleanup_px macros.
v10: Rebase after Mika's merged ppgtt cleanup patch series.
v11: Rebase after final merged version of Mika's ppgtt/scratch
patches.
v12: Fix pdpe start value in trace (Akash)
v13: Define all 4lvl functions in this patch directly, instead of
previous patches, add i915_page_directory_pointer_entry_alloc here,
use test_bit to detect when pdp is already allocated (Akash).
v14: Move pdp allocation into a new gen8_ppgtt_alloc_page_dirpointers
funtion, as we do for pds and pts; move pd and pdp setup functions to
this patch (Akash).
v15: Added kfree(pdp) from previous patch to this (Akash).

Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: NAkash Goel <akash.goel@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Introduces the Page Map Level 4 (PML4), ie. the new top level structure
of the page tables.

To facilitate testing, 48b mode will be available on Broadwell and
GEN9+, when i915.enable_ppgtt = 3.

v2: Remove unnecessary CONFIG_X86_64 checks, ppgtt code is already
32/64-bit safe (Chris).
v3: Add goto free_scratch in temp 48-bit mode init code (Akash).
v4: kfree the pdp until the 4lvl alloc/free patch (Akash).
v5: Postpone 48-bit code in sanitize_enable_ppgtt (Akash).
v6: Keep _insert_pte_entries changes outside this patch (Akash).

Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NAkash Goel <akash.goel@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This transitional patch doesn't do much for the existing code. However,
it should make upcoming patches to use the full 48b address space a bit
easier.

32-bit ppgtt uses just 4 PDPs, while 48-bit ppgtt will have up-to 512;
this patch prepares the existing functions to query the right number of pdps
at run-time. This also means that used_pdpes should also be allocated during
ppgtt_init, as the bitmap size will depend on the ppgtt address range
selected.

v2: Renamed  pdp_free to be similar to  pd/pt (unmap_and_free_pdp).
v3: To facilitate testing, 48b mode will be available on Broadwell and
GEN9+, when i915.enable_ppgtt = 3.
v4: Rebase after s/page_tables/page_table/, added extra information
about 4-level page table formats and use IS_ENABLED macro.
v5: Check CONFIG_X86_64 instead of CONFIG_64BIT.
v6: Rebase after Mika's ppgtt cleanup / scratch merge patch series, and
follow
his nomenclature in pdp functions (there is no alloc_pdp yet).
v7: Rebase after merged version of Mika's ppgtt cleanup patch series.
v8: Rebase after final merged version of Mika's ppgtt/scratch patches.
v9: Introduce PML4 (and 48-bit checks) until next patch (Akash).
v10: Also use test_bit to detect when pd/pt are already allocated (Akash)

Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: NAkash Goel <akash.goel@intel.com>
[danvet: Amend commit message as suggested by Michel.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

gen8_clamp_pd clamps to the next page directory boundary, but the macro
gen8_for_each_pde already has a check to stop at the page directory
boundary.

Furthermore, i915_pte_count also restricts to the next page table
boundary.

v2: Rebase after Mika's ppgtt cleanup / scratch merge patch series.
Suggested-by: NAkash Goel <akash.goel@intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: N"Akash Goel" <akash.goel@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Scratch page is part of struct i915_address_space. Move other
scratch entities into the same struct. This is a preparatory patch
for having only one instance of each scratch_pt/pd.

v2: make commit msg more readable
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com> (v1)
[danvet: Bikeshed summary to avoid confusion with vmas.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Lay out scratch page structure in similar manner than other
paging structures. This allows us to use the same tools for
setup and teardown.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Make paging structure type agnostic *_px macros to access
page dma struct, the backing page and the dma address.

This makes the code less cluttered on internals of
i915_page_dma.

v2: Superfluous const -> nonconst removed
v3: Rebased
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com> (v2)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

All our paging structures have struct page and dma address
for that page.

Add struct for page/dma address pairs and use it to make
the setup and teardown for different paging structures
identical.

Include the page directory offset also in the struct for legacy
gens. Rename it to clearly point out that it is offset into the
ggtt.

v2: Add comment about ggtt_offset (Michel)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The legacy mode mm switch and the execlist context assignment
needs dma address for the page directories.

Introduce a function that encapsulates the scratch_pd dma
fallback if no pd is found.

v2: Rebase, s/ring/req
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com> (v1)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We can have exactly 4GB sized ppgtt with 32bit system.
size_t is inadequate for this.

v2: Convert a lot more places (Daniel)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This way data is available as soon as the view is passed into the call chain.

v2: Store size in bytes instead of pages under the appropriate name. (Chris Wilson)

v3: Use uint64_t instead of size_t. (Daniel Vetter)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> (v2)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Updated the switch_mm() code paths to take a request instead of a ring. This
includes the myriad *_mm_switch functions themselves and a bunch of PDP related
helper functions.

v2: Rebased to newer tree.

For: VIZ-5115
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Reviewed-by: NTomas Elf <tomas.elf@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The final step in removing the OLR from i915_gem_init_hw() is to pass the newly
allocated request structure in to each step rather than passing a ring
structure. This patch updates both i915_ppgtt_init_ring() and
i915_gem_context_enable() to take request pointers.

For: VIZ-5115
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Reviewed-by: NTomas Elf <tomas.elf@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The i915_gem_init_hw() function calls a bunch of smaller initialisation
functions. Multiple of which have generic sections and per ring sections. This
means multiple passes are done over the rings. Each pass writes data to the ring
which floats around in that ring's OLR until some random point in the future
when an add_request() is done by some random other piece of code.

This patch breaks i915_ppgtt_init_hw() in two with the per ring initialisation
now being done in i915_ppgtt_init_ring(). The ring looping is now done at the
top level in i915_gem_init_hw().

v2: Fix dumb loop variable re-use.

For: VIZ-5115
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com> (v1)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Partial view type allows manipulating parts of huge BOs through the GGTT,
which was not previously possible due to constraint that whole object had
to be mapped for any access to it through GGTT.

v2:
- Retain error value from sg_alloc_table (Tvrtko Ursulin)
- Do not zero already zeroed variable (Tvrtko Ursulin)
- Use more common variable types for page size/offset (Tvrtko Ursulin)
v3:
- Only compare additional view parameters when need to (Tvrtko Ursulin)
v4:
- Do zero out the variable that needs to be (bug introduced in v2).

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

GGTT VMA sizes might be smaller than the whole object size due to
different GGTT views.

v2:
- Separate GGTT view constraint calculations from normal view
  constraint calculations (Chris Wilson)
v3:
- Do not bother with debug wording. (Tvrtko Ursulin)
v4:
- Clearer logic for calculating map_and_fenceable (Tvrtko Ursulin)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
[danvet: Drop BUG_ON, it's redudant.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have this neat abstraction between ppgtt and ggtt for (un)bind_vma
and didn't end up using it really. What a shame, so fix this and make
the ->bind_vma hook a bit more useful.
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

It's only used as a flag there, so unconfuse things a bit.
Also separate the bind_vma flag space from the pte_encode flag
space in the code.
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

They change with the address space and not with each vma, so move them
into the right pile of vfuncs. Save 2 pointers per vma and clarifies
the code.
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Like with gen6/7, we can enable bitmap tracking with all the
preallocations to make sure things actually don't blow up.

v2: Rebased to match changes from previous patches.
v3: Without teardown logic, rely on used_pdpes and used_pdes when
freeing page tables.
v4: Rebased after s/page_tables/page_table/.
v5: Rebased after page table generalizations.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

These values are never quite useful for dynamic allocations of the page
tables. Getting rid of them will help prevent later confusion.

v2: Updated to use unmap_and_free_pd functions.
v3: Updated gen8_ppgtt_free after teardown logic was removed.
v4: Rebase after s/page_tables/page_table/.
v5: Keep allocating all page directories in GEN8+ systems with less
than 4GB of memory. Updated gen6_for_all_pdes.
v6: Prevent (harmless) out of range access in gen6_for_all_pdes.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

One important part of this patch is we now write a scratch page
directory into any unused PDP descriptors. This matters for 2 reasons,
first, we're not allowed to just use 0, or an invalid pointer, and second,
we must wipe out any previous contents from the last context.

The latter point only matters with full PPGTT. The former point only
effect platforms with less than 4GB memory.

v2: Updated commit message to point that we must set unused PDPs to the
scratch page.

v3: Unmap scratch_pd in gen8_ppgtt_free.

v4: Initialize scratch_pd. (Mika)

Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to gen6, we will use for_each_pde/for_each_pdpe
and pte/pde/pdpe_index to iterate over these new structures.

v2: Match trace_i915_va_teardown params
v3: Multiple rebases.
v4: Updated to use unmap_and_free_pt.
v5: teardown_va_range logic no longer needed.
v6: Rebase after s/page_tables/page_table/.
v7: Renamed commit to match what it does now (it was "Use dynamic
allocation idioms on free").
v8: Prevent (harmless) out of range access in gen8_for_each_pde and
gen8_for_each_pdpe_e.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
[danvet: s/BUG/WARN/]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Lets try to keep this consistent:

Page Directory Pointer (PDP).
Page Directory (PD), also known as page directory pointer entries.
Page Table (PT), also known as page directory entries.

s/struct i915_page_table_entry/struct i915_page_table/
s/struct i915_page_directory_entry/struct i915_page_directory/
s/struct i915_page_directory_pointer_entry/struct
i915_page_directory_pointer/
Suggested-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

To allow for views where the view type is not defined by the view type only,
like it is in stereo or rotated 90 degree view, change the semantic to require
the whole view structure for comparison when we match a GGTT view.

This allows including parameters like offset to be included in the view which
is useful for eg. partial views.

v3:
- Rely on ggtt_view type being 0 for non-GGTT vma's, which equals to
  I915_GGTT_VIEW_NORMAL. (Daniel Vetter)
- Do not use potentially slower comparison when we only want to know if
  something is or is not a normal view.
- Rebase on top of rotated view patches. Add rotated view singleton.
- If one view is missing in comparison they're equal only if both are missing.

v4:
- Use comparison helper in obj_to_ggtt_view too. (Tvrtko Ursulin)
- Do WARN_ON if one view is NULL. (Tvrtko Ursulin)

Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This patch continues on the idea from "Track GEN6 page table usage".
From here on, in the steady state, PDEs are all pointing to the scratch
page table (as recommended in the spec). When an object is allocated in
the VA range, the code will determine if we need to allocate a page for
the page table. Similarly when the object is destroyed, we will remove,
and free the page table pointing the PDE back to the scratch page.

Following patches will work to unify the code a bit as we bring in GEN8
support. GEN6 and GEN8 are different enough that I had a hard time to
get to this point with as much common code as I do.

The aliasing PPGTT must pre-allocate all of the page tables. There are a
few reasons for this. Two trivial ones: aliasing ppgtt goes through the
ggtt paths, so it's hard to maintain, we currently do not restore the
default context (assuming the previous force reload is indeed
necessary). Most importantly though, the only way (it seems from
empirical evidence) to invalidate the CS TLBs on non-render ring is to
either use ring sync (which requires actually stopping the rings in
order to synchronize when the sync completes vs. where you are in
execution), or to reload DCLV.  Since without full PPGTT we do not ever
reload the DCLV register, there is no good way to achieve this. The
simplest solution is just to not support dynamic page table
creation/destruction in the aliasing PPGTT.

We could always reload DCLV, but this seems like quite a bit of excess
overhead only to save at most 2MB-4k of memory for the aliasing PPGTT
page tables.

v2: Make the page table bitmap declared inside the function (Chris)
Simplify the way scratching address space works.
Move the alloc/teardown tracepoints up a level in the call stack so that
both all implementations get the trace.

v3: Updated trace event to spit out a name

v4: Aliasing ppgtt is now initialized differently (in setup global gtt)

v5: Rebase to latest code. Also removed unnecessary aliasing ppgtt check
for trace, as it is no longer possible after the PPGTT cleanup patch series
of a couple of months ago (Daniel).

v6: Implement changes from code review (Daniel):
 - allocate/teardown_va_range calls added.
 - Add a scratch page allocation helper (only need the address).
 - Move trace events to a new patch.
 - Use updated mark_tlbs_dirty.
 - Moved pt preallocation for aliasing ppgtt into gen6_ppgtt_init.

v7: teardown_va_range removed (Daniel).
    In init, gen6_ppgtt_clear_range call is only needed for aliasing ppgtt.

v8: Rebase after s/page_tables/page_table/.

v9: Remove unnecessary scratch flag in page_table struct, future patches
can just compare against ppgtt->scratch_pt, and alloc_pt_scratch becomes
redundant. Initialize scratch_pt and pt. (Mika)

v10: Clean up aliasing ppgtt init error path and prevent leaking the
ppgtt obj when init fails. (Mika)
Updated commit author. (Daniel)

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v4+)
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Found by static analysis tool, this was harmless as the pt was not
used out of scope though.

Introduced by commit 678d96fb
("drm/i915: Track GEN6 page table usage").

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>