drm/i915: Drop no-semaphore boosting

Now that we have fast timeslicing on semaphores, we no longer need to
prioritise none-semaphore work as we will yield any work blocked on a
semaphore to the next in the queue. Previously with no timeslicing,
blocking on the semaphore caused extremely bad scheduling with multiple
clients utilising multiple rings. Now, there is no impact and we can
remove the complication.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513173504.28322-1-chris@chris-wilson.co.uk

drm/i915: Drop I915_RESET_TIMEOUT and friends

These were used to set various timeouts for the reset procedure
(deciding when the engine was dead, and even if the reset itself was not
making forward progress). No longer used.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513074809.18194-14-chris@chris-wilson.co.uk

drm/i915: Mark the addition of the initial-breadcrumb in the request

The initial-breadcrumb is used to mark the end of the awaiting and the
beginning of the user payload. We verify that we do not start the user
payload before all signaler are completed, checking our semaphore setup
by looking for the initial breadcrumb being written too early. We also
want to ensure that we do not add semaphore waits after we have already
closed the semaphore section, an issue for later deferred waits.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513165937.9508-2-chris@chris-wilson.co.uk

drm/i915/gem: Remove redundant exec_fence

Since there can only be one of in_fence/exec_fence, just use the single
in_fence local.

v2: Consolidate lookup

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513180937.28992-1-chris@chris-wilson.co.uk

drm/i915: Remove duplicate inline specifier on write_pte

When building with clang:

 drivers/gpu/drm/i915/gt/gen8_ppgtt.c:392:24: warning: duplicate
 'inline' declaration specifier [-Wduplicate-decl-specifier]
 declaration specifier [-Wduplicate-decl-specifier]
 static __always_inline inline void
                        ^
 include/linux/compiler_types.h:138:16: note: expanded from macro
 'inline'
 #define inline inline __gnu_inline __inline_maybe_unused notrace
                ^
 1 warning generated.

__always_inline is defined as 'inline __attribute__((__always_inline))'
so we do not need to specify it twice.

Fixes: 84eac0c65940 ("drm/i915/gt: Force pte cacheline to main memory")
Link: https://github.com/ClangBuiltLinux/linux/issues/1024
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513182340.3968668-1-natechancellor@gmail.com

drm/i915/gt: Suspend tasklets before resume sanitization

It is possible for a residual tasklet to be pending execution as we
resume (whether that's some prior test kicking off the tasklet, or if we
are in a suspend/resume stress test). As such, we do not want that
tasklet to execute in the middle of our sanitization, such that it sees
the poisoned state. For example,

<4>[  449.386553] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
<4>[  449.386555] CPU: 1 PID: 5115 Comm: i915_selftest Tainted: G     U  W         5.7.0-rc4-CI-CI_DRM_8472+ #1
<4>[  449.386556] Hardware name: Intel Corporation Ice Lake Client Platform/IceLake U DDR4 SODIMM PD RVP TLC, BIOS ICLSFWR1.R00.3183.A00.1905020411 05/02/2019
<4>[  449.386585] RIP: 0010:process_csb+0x6bf/0x830 [i915]
<4>[  449.386588] Code: 00 48 c7 c2 10 bc 4c a0 48 c7 c7 d4 75 34 a0 e8 87 0e e6 e0 bf 01 00 00 00 e8 9d e0 e5 e0 31 f6 bf 09 00 00 00 e8 e1 ba d6 e0 <0f> 0b 8b 87 10 05 00 00 85 c0 0f 85 5f f9 ff ff 48 c7 c1 70 a5 4f
<4>[  449.386591] RSP: 0018:ffffc90000170ea0 EFLAGS: 00010297
<4>[  449.386594] RAX: 0000000080000101 RBX: 0000000000000000 RCX: 0000000000000000
<4>[  449.386596] RDX: ffff88849d5bc040 RSI: 0000000000000000 RDI: 0000000000000009
<4>[  449.386598] RBP: ffffc90000170f00 R08: 0000000000000000 R09: 0000000000000000
<4>[  449.386600] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88843ccea018
<4>[  449.386602] R13: ffff88843ccea658 R14: ffff88843ccea640 R15: ffff88843ccea000
<4>[  449.386605] FS:  00007f826a813300(0000) GS:ffff88849fe80000(0000) knlGS:0000000000000000
<4>[  449.386607] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4>[  449.386609] CR2: 0000560366b94280 CR3: 000000048ba02002 CR4: 0000000000760ee0
<4>[  449.386611] PKRU: 55555554
<4>[  449.386613] Call Trace:
<4>[  449.386616]  <IRQ>
<4>[  449.386646]  ? execlists_submission_tasklet+0xcf/0x140 [i915]
<4>[  449.386674]  execlists_submission_tasklet+0x2f/0x140 [i915]
<4>[  449.386679]  tasklet_action_common.isra.16+0x6c/0x1c0
<4>[  449.386684]  __do_softirq+0xdf/0x49e
<4>[  449.386687]  irq_exit+0xba/0xc0
<4>[  449.386690]  smp_apic_timer_interrupt+0xb7/0x280
<4>[  449.386693]  apic_timer_interrupt+0xf/0x20
<4>[  449.386695]  </IRQ>
<4>[  449.386698] RIP: 0010:_raw_spin_unlock_irqrestore+0x49/0x60
<4>[  449.386701] Code: c7 02 75 1f 53 9d e8 26 ab 75 ff bf 01 00 00 00 e8 7c a3 69 ff 65 8b 05 7d 9b 5c 7e 85 c0 74 0c 5b 5d c3 e8 09 aa 75 ff 53 9d <eb> df e8 ca 39 5b ff 5b 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00
<4>[  449.386703] RSP: 0018:ffffc90000a6b950 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
<4>[  449.386706] RAX: 0000000080000001 RBX: 0000000000000202 RCX: 0000000000000000
<4>[  449.386708] RDX: ffff88849d5bc040 RSI: ffff88849d5bc900 RDI: ffffffff82386f12
<4>[  449.386710] RBP: ffff88847d400f00 R08: ffff88849d5bc900 R09: 0000000000000000
<4>[  449.386712] R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffff0b0b
<4>[  449.386714] R13: 000000000000000c R14: ffff88847d40bf70 R15: ffff88847d40cef8
<4>[  449.386742]  reset_csb_pointers+0x59/0x140 [i915]
<4>[  449.386769]  execlists_sanitize+0x3e/0x60 [i915]
<4>[  449.386797]  gt_sanitize+0xd6/0x260 [i915]

As part of the reset preparation, engine->reset.prepare() prevents the
tasklet from running, so pull the sanitization inside the critical
section for reset.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1812
Fixes: 23122a4d992b ("drm/i915/gt: Scrub execlists state on resume")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513122826.27484-1-chris@chris-wilson.co.uk

drm/i915: Make active_pipes check skl specific

Seems that only skl needs to have SAGV turned off
for multipipe scenarios, so lets do it this way.

If anything blows up - we can always revert this patch.

v2: Changed if condition to look better (Ville).

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
[vsyrjala: wrapped long line to appease checkpatch]
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513093816.11466-4-stanislav.lisovskiy@intel.com

drm/i915: Extract skl SAGV checking

Introduce platform dependent SAGV checking in
combination with bandwidth state pipe SAGV mask.

This is preparation to adding TGL support, which
requires different way of SAGV checking.

v2, v3, v4, v5, v6: Fix rebase conflict

v7: - Nuke icl specific function, use skl
      for icl as well, gen specific active_pipes
      check to be added in the next patch(Ville)

v8: - Use more generic intel_crtc_can_enable_sagv
      for checking(Ville)

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513093816.11466-3-stanislav.lisovskiy@intel.com

drm/i915: Introduce skl_plane_wm_level accessor.

For future Gen12 SAGV implementation we need to
seemlessly alter wm levels calculated, depending
on whether we are allowed to enable SAGV or not.

So this accessor will give additional flexibility
to do that.

Currently this accessor is still simply working
as "pass-through" function. This will be changed
in next coming patches from this series.

v2: - plane_id -> plane->id(Ville Syrjälä)
    - Moved wm_level var to have more local scope
      (Ville Syrjälä)
    - Renamed yuv to color_plane(Ville Syrjälä) in
      skl_plane_wm_level

v3: - plane->id -> plane_id(this time for real, Ville Syrjälä)
    - Changed colorplane id type from boolean to int as index
      (Ville Syrjälä)
    - Moved crtc_state param so that it is first now
      (Ville Syrjälä)
    - Moved wm_level declaration to tigher scope in
      skl_write_plane_wm(Ville Syrjälä)

v4: - Started to use enum values for color plane
    - Do sizeof for a type what we are memset'ing
    - Zero out wm_uv as well(Ville Syrjälä)

v5: - Fixed rebase conflict caused by COLOR_PLANE_*
      enum removal

v6: - Do not use skl_plane_wm_level accessor in skl_allocate_pipe_ddb

v7: - Get rid of wm_uv, which is not used in skl_plane_write_wm(Ville)

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513093816.11466-2-stanislav.lisovskiy@intel.com

drm/i915/gt: Reset execlists registers before HWSP

Upon gt resume, we first poison then sanitize the engine. However, our
testing shows that gen9 will very rarely retain the poisoned value from
the HWSP mappings of the execlists status registers. This suggests that
it is reading back from the HWSP, so rejig the register reset.

v2: Maybe RING_CONTEXT_STATUS_PTR is write masked. It is.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1812
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200513100120.11617-1-chris@chris-wilson.co.uk

drm/i915/ehl: Restrict w/a 1607087056 for EHL/JSL

This w/a is fixed in B0 stepping and needs to be restricted for
A0 stepping only.
Bspec: 33451

Signed-off-by: Swathi Dhanavanthri <swathi.dhanavanthri@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200512180050.6785-1-swathi.dhanavanthri@intel.com

drm/i915: Handle idling during i915_gem_evict_something busy loops

i915_gem_evict_something() is charged with finding a slot within the GTT
that we may reuse. Since our goal is not to stall, we first look for a
slot that only overlaps idle vma. To this end, on the first pass we move
any active vma to the end of the search list. However, we only stopped
moving active vma after we see the first active vma twice. If during the
search, that first active vma completed, we would not notice and keep on
extending the search list.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1746
Fixes: 2850748ef876 ("drm/i915: Pull i915_vma_pin under the vm->mutex")
Fixes: b1e3177bd1d8 ("drm/i915: Coordinate i915_active with its own mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200509115217.26853-1-chris@chris-wilson.co.uk

drm/i915/gt: Restore Cherryview back to full-ppgtt

This reverts commit 0b718ba1e884f64dce27c19311dd2859b87e56b9.

There are still some residual issues with asynchronous binding and
execution, but since commit 92581f9fb99c ("drm/i915: Immediately execute
the fenced work") we prefer not to use asynchronous binds, and the
remaining issues do not seem restricted to Cherryview [at least the ones
seen over a few dozen CI runs, less frequent issues are sure to be
discovered!]

These issues seem to be mitigated, if not eliminated entirely, by the
previous commit 84eac0c65940 ("drm/i915/gt: Force pte cacheline to main
memory").

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200510102431.21959-3-chris@chris-wilson.co.uk

drm/i915/gt: Force pte cacheline to main memory

We have problems of tgl not seeing a valid pte entry when iommu is
enabled. Add heavy handed flushing of entry modification by flushing the
cpu, cacheline and then wcb. This forces the pte out to main memory past
this point regarless of promises of coherency.

This is an evolution of an experimental patch from Chris Wilson of adding
wmb for coherent partners, by adding a clflush to force the cache->memory
step.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1840
Testcase: igt/gem_exec_fence/parallel
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511160803.15407-1-mika.kuoppala@linux.intel.com

drm/i915: Remove unused HAS_FWTABLE macro

It has been unused since commit ccb2aceaaa5f ("drm/i915: use vfuncs for
reg_read/write_fw_domains").

Signed-off-by: Pascal Terjan <pterjan@google.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200510212521.128869-1-pterjan@google.com

drm/i915/selftests: Always flush before unpining after writing

Be consistent, and even when we know we had used a WC, flush the mapped
object after writing into it. The flush understands the mapping type and
will only clflush if !I915_MAP_WC, but will always insert a wmb [sfence]
so that we can be sure that all writes are visible.

v2: Add the unconditional wmb so we are know that we always flush the
writes to memory/HW at that point.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511141304.599-1-chris@chris-wilson.co.uk

drm/i915: Emit await(batch) before MI_BB_START

Be consistent and ensure that we always emit the asynchronous waits
prior to issuing instructions that use the address. This ensures that if
we do emit GPU commands to do the await, they are before our use!

Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200510102431.21959-1-chris@chris-wilson.co.uk

drm/i915: Use stashed away hpd isr bits in intel_digital_port_connected()

Get rid of several platform specific variants of
intel_digital_port_connected() and just use the ISR bits we've
stashed away.

v2: Duplicate stuff to avoid exposing platform specific
    functions across files (Jani)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311155422.3043-4-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

drm/i915: Stash hpd status bits under dev_priv

Instead of constnantly having to figure out which hpd status bit
array to use let's store them under dev_priv.

Should perhaps take this further and stash even more stuff to
make the hpd handling more abstract yet.

v2: Remeber cnp (Imre)
    Add MISSING_CASE() for unknown PCHs (Imre)

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507114808.6150-1-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

drm/i915: Turn intel_digital_port_connected() in a vfunc

Let's get rid of the platform if ladders in
intel_digital_port_connected() and make it a vfunc. Now the if
ladders are at the encoder initialization which makes them a bit
less convoluted.

v2: Add forward decl for intel_encoder in intel_tc.h
v3: Duplicate stuff to avoid exposing platform specific
    functions across files (Jani)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200311155422.3043-2-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

drm/i915: Fix glk watermark calculations

GLK wants the +1 adjustement for the "blocks per line" value
for x-tile/y-tile, just like cnl+.

Also the x-tile and linear cases are almost identical. The only
difference is this +1 which is always done for glk+, and only
done for linear on skl/bxt. Let's unify it to a single branch
with a special case for the +1, just like we do for y-tile.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430125822.21985-1-ville.syrjala@linux.intel.com
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

drm/i915/mst: Wait for ACT sent before enabling the pipe

The correct sequence according to bspec is to wait for the ACT sent
status before we turn on the pipe. Make it so.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507144125.2458-1-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

drm/i915: Tidy awaiting on dma-fences

Just tidy up the return handling for completed dma-fences. While it may
return errors for invalid fence, we already know that we have a good
fence and the only error will be an already signaled fence.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511075722.13483-5-chris@chris-wilson.co.uk

drm/i915: Make intel_timeline_init static

Commit fb5970da1b42 ("drm/i915/gt: Use the kernel_context to measure the
breadcrumb size") removed the last external user for intel_timeline_init.
Mark it static.

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511102201.9275-1-mika.kuoppala@linux.intel.com

drm/i915/gt: Mark up the racy read of execlists->context_tag

Since we are using bitops on context_tag to allow us to reserve and
release inflight tags concurrently, the scan for the next bit is
intentionally racy.

[  516.446854] BUG: KCSAN: data-race in execlists_schedule_in.isra.0 [i915] / execlists_schedule_out [i915]
[  516.446874]
[  516.446886] write (marked) to 0xffff8881f7644048 of 8 bytes by interrupt on cpu 2:
[  516.447076]  execlists_schedule_out+0x538/0x6a0 [i915]
[  516.447263]  process_csb+0x10b/0x3d0 [i915]
[  516.447449]  execlists_submission_tasklet+0x30/0x170 [i915]
[  516.447468]  tasklet_action_common.isra.0+0x42/0x90
[  516.447484]  __do_softirq+0xc8/0x206
[  516.447498]  irq_exit+0xcd/0xe0
[  516.447516]  do_IRQ+0x44/0xc0
[  516.447535]  ret_from_intr+0x0/0x1c
[  516.447550]  cpuidle_enter_state+0x199/0x400
[  516.447572]  cpuidle_enter+0x50/0x90
[  516.447587]  do_idle+0x197/0x1e0
[  516.447600]  cpu_startup_entry+0x14/0x20
[  516.447619]  start_secondary+0xf9/0x130
[  516.447643]  secondary_startup_64+0xa4/0xb0
[  516.447655]
[  516.447671] read to 0xffff8881f7644048 of 8 bytes by task 460 on cpu 1:
[  516.447863]  execlists_schedule_in.isra.0+0x3cf/0x5a0 [i915]
[  516.448064]  execlists_dequeue+0xf8f/0x1690 [i915]
[  516.448252]  __execlists_submission_tasklet+0x48/0x60 [i915]
[  516.448440]  execlists_submit_request+0x2e2/0x310 [i915]
[  516.448634]  submit_notify+0x8f/0xc8 [i915]
[  516.448820]  __i915_sw_fence_complete+0x61/0x420 [i915]
[  516.449005]  i915_sw_fence_complete+0x58/0x80 [i915]
[  516.449208]  i915_sw_fence_commit+0x16/0x20 [i915]
[  516.449399]  __i915_request_queue+0x60/0x70 [i915]
[  516.449590]  i915_gem_do_execbuffer+0x33f1/0x4a00 [i915]
[  516.449782]  i915_gem_execbuffer2_ioctl+0x2a2/0x550 [i915]
[  516.449800]  drm_ioctl_kernel+0xe9/0x130
[  516.449814]  drm_ioctl+0x27d/0x45e
[  516.449827]  ksys_ioctl+0x89/0xb0
[  516.449842]  __x64_sys_ioctl+0x42/0x60
[  516.449864]  do_syscall_64+0x6e/0x2c0
[  516.449878]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200511075722.13483-1-chris@chris-wilson.co.uk

drm/i915: Replace zero-length array with flexible-array

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507185408.GA14561@embeddedor

drm/i915: Replace the hardcoded I915_FENCE_TIMEOUT

Expose the hardcoded timeout for unsignaled foreign fences as a Kconfig
option, primarily to allow brave systems to disable the timeout and
solely rely on correct signaling.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200509105021.12542-1-chris@chris-wilson.co.uk

drm/i915: Prevent using semaphores to chain up to external fences

The downside of using semaphores is that we lose metadata passing
along the signaling chain. This is particularly nasty when we
need to pass along a fatal error such as EFAULT or EDEADLK. For
fatal errors we want to scrub the request before it is executed,
which means that we cannot preload the request onto HW and have
it wait upon a semaphore.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508092933.738-3-chris@chris-wilson.co.uk

drm/i915: Peel dma-fence-chains for await

To allow faster engine to engine synchronization, peel the layer of
dma-fence-chain to expose potential i915 fences so that the
i915_request code can emit HW semaphore wait/signal operations in the
ring which is faster than waking up the host to submit unblocked
workloads after interrupt notification.

This is similar to the peeling we do for e.g. dma_fence_array.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508185448.29709-1-chris@chris-wilson.co.uk

drm/i915/gt: Improve precision on defer_request assert

The kernel_context does not use initial-breadcrumbs, so when we ask if
its requests have started we do so by comparing against the completion
seqno of the previous request. This is very imprecise, not precise
enough for the defer_request assertion.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1847
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508104220.9872-1-chris@chris-wilson.co.uk

drm/i915: Pull waiting on an external dma-fence into its routine

As a means for a small code consolidation, but primarily to start
thinking more carefully about internal-vs-external linkage, pull the
pair of i915_sw_fence_await_dma_fence() calls into a common routine.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508092933.738-2-chris@chris-wilson.co.uk

drm/i915: Ignore submit-fences on the same timeline

While we ordinarily do not skip submit-fences due to the accompanying
hook that we want to callback on execution, a submit-fence on the same
timeline is meaningless.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200508092933.738-1-chris@chris-wilson.co.uk

drm/i915/gen12: Add aux table invalidate for all engines

All engines, exception being blitter as it does not
care about the form, can access compressed surfaces.

So we need to add forced aux table invalidates
for those engines.

v2: virtual instance masking (Chris)
v3: bug on if not found (Chris)

References: d248b371f747 ("drm/i915/gen12: Invalidate aux table entries forcibly")
References bspec#43904, hsdes#1809175790
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chuansheng Liu <chuansheng.liu@intel.com>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507142045.8668-1-mika.kuoppala@linux.intel.com

drm/i915: Remove wait priority boosting

Upon waiting a request (when asked), we gave that request a small
priority boost, not enough for it to cause preemption, but enough for it
to be scheduled next before all equals. We also used that bit to give
new clients a small priority boost, similar to FQ_CODEL, such that we
favoured short interactive tasks ahead of long running streams.

However, this is causing lots of complications with timeslicing where we
both want to honour the boost and yet ignore it. Those complications
cause unexpected user behaviour (tasks not being timesliced and run
concurrently as epxected), and the easiest way to resolve that is to
remove the boost. Hopefully, we can find a compromise again if we need
to, but in theory timeslicing itself and future more advanced schedulers
should give us the interactivity boost we seek.

Testcase: igt/gem_exec_schedule/lateslice
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507152338.7452-3-chris@chris-wilson.co.uk

drm/i915: Mark concurrent submissions with a weak-dependency

We recorded the dependencies for WAIT_FOR_SUBMIT in order that we could
correctly perform priority inheritance from the parallel branches to the
common trunk. However, for the purpose of timeslicing and reset
handling, the dependency is weak -- as we the pair of requests are
allowed to run in parallel and not in strict succession.

The real significance though is that this allows us to rearrange
groups of WAIT_FOR_SUBMIT linked requests along the single engine, and
so can resolve user level inter-batch scheduling dependencies from user
semaphores.

Fixes: c81471f5e95c ("drm/i915: Copy across scheduler behaviour flags across submit fences")
Testcase: igt/gem_exec_fence/submit
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507155109.8892-1-chris@chris-wilson.co.uk

drm/i915/gen12: Invalidate aux table entries forcibly

Aux table invalidation can fail on update. So
next access may cause memory access to be into stale entry.

Proposed workaround is to invalidate entries between
all batchbuffers.

v2: correct register address (Yang)
v3: respect the order (Chris)

References bspec#43904, hsdes#1809175790
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chuansheng Liu <chuansheng.liu@intel.com>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Cc: Yang A Shi <yang.a.shi@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506165310.1239-1-mika.kuoppala@linux.intel.com

drm/i915/gen12: Flush L3

Flush TDL,L3 and EUs

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506144734.29297-3-mika.kuoppala@linux.intel.com

drm/i915/gen12: Fix HDC pipeline flush

HDC pipeline flush is bit on the first dword of
the PIPE_CONTROL, not the second. Make it so.

v2: function naming (Chris)

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506144734.29297-2-mika.kuoppala@linux.intel.com

Revert "drm/i915/tgl: Include ro parts of l3 to invalidate"

This reverts commit 62037ffff229b7d94f1db5ef8d2e2ec819832ef3.

L3 ro cache invalidation is part of the dword0 of pipe
control. Also it is not relevant to this gen.

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506144734.29297-1-mika.kuoppala@linux.intel.com

drm/i915: Propagate error from completed fences

We need to preserve fatal errors from fences that are being terminated
as we hook them up.

Fixes: ef4688497512 ("drm/i915: Propagate fence errors")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506162136.3325-1-chris@chris-wilson.co.uk

drm/i915/icp: Add Wa_14010685332

We need to toggle a SDE chicken bit on and then off as the final
step when disabling interrupts in preparation for runtime suspend.

Bspec: 33450
Bspec: 8402
Cc: Bob Paauwe <bob.j.paauwe@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501213701.371443-1-matthew.d.roper@intel.com
Reviewed-by: Bob Paauwe <bob.j.paauwe@intel.com>

drm/i915/gt: Stop holding onto the pinned_default_state

As we only restore the default context state upon banning a context, we
only need enough of the state to run the ring and nothing more. That is
we only need our bare protocontext.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504180745.15645-1-chris@chris-wilson.co.uk

drm/i915/execlists: Record the active CCID from before reset

If we cannot trust the reset will flush out the CS event queue such that
process_csb() reports an accurate view of HW, we will need to search the
active and pending contexts to determine which was actually running at
the time we issued the reset.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200505084629.31365-1-chris@chris-wilson.co.uk

drm/i915: Added required new PCode commands

We need a new PCode request commands and reply codes
to be added as a prepartion patch for QGV points
restricting for new SAGV support.

v2: - Extracted those changes into separate patch
      (Ville Syrjälä)

v3: - Moved new PCode masks to another place from
      PCode commands(Ville)

v4: - Moved new PCode masks to correspondent PCode
      command, with identation(Ville)
    - Changed naming to ICL_ instead of GEN11_
      to fit more nicely into existing definition
      style.

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200505102247.32452-5-stanislav.lisovskiy@intel.com

drm/i915/tgl+: Fix interrupt handling for DP AUX transactions

Unmask/enable AUX interrupts on all ports on TGL+. So far the interrupts
worked only on port A, which meant each transaction on other ports took
10ms.

Cc: <stable@vger.kernel.org> # v5.4+
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504075828.20348-1-imre.deak@intel.com

drm/i915/gt: Small tidy of gen8+ breadcrumb emission

Use a local to shrink a line under 80 columns, and refactor the common
emit_xcs_breadcrumb() wrapper of ggtt-write.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504180507.6017-1-chris@chris-wilson.co.uk

drm/i915/selftests: Repeat the rps clock frequency measurement

Repeat the measurement of the clock frequency a few times and use the
median to try and reduce the systematic measurement error.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504044903.7626-6-chris@chris-wilson.co.uk

drm/i915/display: Warn if the FBC is still writing to stolen on removal

If the FBC is still writing into stolen, it will overwrite any future
users of that stolen region. Check before release, just to ease any
concerns -- we can remove it again later if it is barking up the wrong
tree.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1635
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200503180034.20010-1-chris@chris-wilson.co.uk

drm/i915: Don't enable WaIncreaseLatencyIPCEnabled when IPC is disabled

In commit 5a7d202b1574, a logical AND was erroneously changed to an OR,
causing WaIncreaseLatencyIPCEnabled to be enabled unconditionally for
kabylake and coffeelake, even when IPC is disabled. Fix the logic so
that WaIncreaseLatencyIPCEnabled is only used when IPC is enabled.

Fixes: 5a7d202b1574 ("drm/i915: Drop WaIncreaseLatencyIPCEnabled/1140 for cnl")
Cc: stable@vger.kernel.org # 5.3.x+
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430214654.51314-1-sultan@kerneltoast.com

drm/i915: Streamline the artihmetic

All these ROUNDING_FACTORs and whatnot are making this thing hard to
read. Get rid of them. And let's massage some of the fractions to
give us less questionable intermediate results and perhaps less
divisions.

Also looks like a good helping of 64bit math stuff is needed to
avoid some of overflows present in the current code. There
might still be a few overflows, namely when calculating
link_clks_available/samples_room (would require a huge hblank
though), and potentially when calculating hblank_rise (not sure
how large link_clks_active can get).

It looks like we're still not calculating exactly what the spec says
since we truncate tu_data and tu_line early. But I'm too lazy to
figure out if we could avoid that.

v2: Fix typo in commit msg (Uma)
    Remove ROUNDING_FACTOR define (Uma)
    s/5*link_clk+5*cdclk/5*(link_clk+cdclk)/ (Chris)

Cc: Anshuman Gupta <anshuman.gupta@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429185457.26235-3-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

drm/i915: Rename variables to be consistent with bspec

Since the code seems insistent on using the variable names from the
bspec formulat, let's be consistent and use those names for all
the things. For some reason 'link_clk' and 'lanes' were left out
in the code until now.

Cc: Anshuman Gupta <anshuman.gupta@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429185457.26235-2-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

drm/i915: Nuke mode.vrefresh usage

mode.vrefresh is rounded to the nearest integer. You don't want to use
it anywhere that requires precision. Also I want to nuke it.
vtotal*vrefresh == 1000*clock/htotal, so let's use the latter.

Cc: Anshuman Gupta <anshuman.gupta@intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429185457.26235-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

drm/i915: Remove cnl pre-prod workarounds

Remove all the stepping dependent cnl workarounds. Bspec lists
more steppings than this so presumably these are classed as
pre-production. And this is cnl after all so no one should
really care anyway.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430125822.21985-2-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drm/i915/fbc: Require linear fb stride to be multiple of 512 bytes on gen9/glk

Display WA #1105 says that FBC requires PLANE_STRIDE to be a multiple
of 512 bytes on gen9 and glk.

This is definitely true for glk as certain tests (such as
igt/kms_big_fb/linear-16bpp-rotate-0) are now failing when the
display resolution results in a plane stride which is not a
multiple of 512 bytes.

Curiously I was not able to reproduce this on a KBL. First I
suspected that our use of the FBC override stride explain this,
but after trying to use the override stride on glk the test
still failed. I did try both the old CHICKEN_MISC_4 way and
the new FBC_STRIDE way, neither had any effect on the result.

Anyways, we need this at least on glk. But let's trust the spec
and apply the w/a for all gen9 as well, despite being unable to
reproduce the problem.

v2: s/FBC_CHICKEN/FBC_STRIDE/ in commit msg

Cc: José Roberto de Souza <jose.souza@intel.com>
Fixes: 691f7ba58d52 ("drm/i915/display/fbc: Make fences a nice-to-have for GEN9+")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429101034.8208-2-ville.syrjala@linux.intel.com
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>

drm/i915: Rename bw_state to new_bw_state

That is a preparation patch before next one where we
introduce old_bw_state and a bunch of other changes
as well.
In a review comment it was suggested to split out
at least that renaming into a separate patch, what
is done here.

v2: Removed spurious space

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200423075902.21892-8-stanislav.lisovskiy@intel.com

drm/i915: Track active_pipes in bw_state

We need to calculate SAGV mask also in a non-modeset
commit, however currently active_pipes are only calculated
for modesets in global atomic state, thus now we will be
tracking those also in bw_state in order to be able to
properly access global data.

v2: - Removed pre/post plane SAGV updates from modeset(Ville)
    - Now tracking active pipes in intel_can_enable_sagv(Ville)

v3: - lock global state if active_pipes change as well(Ville)

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430195634.7666-1-stanislav.lisovskiy@intel.com

drm/i915: Use bw state for per crtc SAGV evaluation

Future platforms require per-crtc SAGV evaluation
and serializing global state when those are changed
from different commits.

v2: - Add has_sagv check to intel_crtc_can_enable_sagv
      so that it sets bit in reject mask.
    - Use bw_state in intel_pre/post_plane_enable_sagv
      instead of atomic state

v3: - Fixed rebase conflict, now using
      intel_atomic_crtc_state_for_each_plane_state in
      order to call it from atomic check
v4: - Use fb modifier from plane state

v5: - Make intel_has_sagv static again(Ville)
    - Removed unnecessary NULL assignments(Ville)
    - Removed unnecessary SAGV debug(Ville)
    - Call intel_compute_sagv_mask only for modesets(Ville)
    - Serialize global state only if sagv results change, but
      not mask itself(Ville)

v6: - use lock global state instead of serialize(Ville)
v7: - use both global state lock and serialize depending on
      if we need to change only global state or access hw
      (Ville)

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Cc: Ville Syrjälä <ville.syrjala@intel.com>
Cc: James Ausmus <james.ausmus@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430191757.18206-1-stanislav.lisovskiy@intel.com

drm/i915/gem: Implement legacy MI_STORE_DATA_IMM

The older arches did not convert MI_STORE_DATA_IMM to using the GTT, but
left them writing to a physical address. The notes suggest that the
primary reason would be so that the writes were cache coherent, as the
CPU cache uses physical tagging. As such we did not implement the
legacy variant of MI_STORE_DATA_IMM and so left all the relocations
synchronous -- but with a small function to convert from the vma address
into the physical address, we can implement asynchronous relocs on these
older arches, fixing up a few tests that require them.

In order to be able to test the legacy paths, refactor the gpu
relocations so that we can hook them up to a selftest.

v2: Use an array of offsets not enum labels for the selftest
v3: Refactor the common igt_hexdump()

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/757
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504140629.28240-1-chris@chris-wilson.co.uk

drm/i915/gem: Specify address type for chained reloc batches

It is required that a chained batch be in the same address domain as its
parent, and also that must be specified in the command for earlier gen
as it is not inferred from the chaining until gen6.

Fixes: 964a9b0f611e ("drm/i915/gem: Use chained reloc batches")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504125149.4396-1-chris@chris-wilson.co.uk

drm/i915: Allow some leniency in PCU reads

Extend the timeout for pcode reads to 20ms as they should not be
performed along critical paths, and succeeding after a short delay is
better than failing entirely.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1800
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504044903.7626-1-chris@chris-wilson.co.uk

drm/i915/gem: Lazily acquire the device wakeref for freeing objects

We only need the device wakeref on freeing the objects if we have to
unbind the object from the global GTT, or otherwise update device
information. If the objects are clean, we never need the wakeref, so
avoid taking until required.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200503171513.18704-1-chris@chris-wilson.co.uk

drm/i915/gt: Sanitize RPS interrupts upon resume

Currently we clear and disable the RPS pm interrupts on module load, and
presume that they remain disabled forevermore. However, the mask is
cleared on suspend and so after resume they may start showing up again
unexepectedly.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1811
Fixes: 8e99299a04bc ("drm/i915/gt: Track use of RPS interrupts in flags")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi@etezian.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200502173512.32353-1-chris@chris-wilson.co.uk

drm/i915/gem: Try an alternate engine for relocations

If at first we don't succeed, try try again.

Not all engines may support the MI ops we need to perform asynchronous
relocation patching, and so we end up falling back to a synchronous
operation that has a liability of blocking. However, Tvrtko pointed out
we don't need to use the same engine to perform the relocations as we
are planning to execute the execbuf on, and so if we switch over to a
working engine, we can perform the relocation asynchronously. The user
execbuf will be queued after the relocations by virtue of fencing.

This patch creates a new context per execbuf requiring asynchronous
relocations on an unusable engines. This is perhaps a bit excessive and
can be ameliorated by a small context cache, but for the moment we only
need it for working around a little used engine on Sandybridge, and only
if relocations are actually required to an active batch buffer.

Now we just need to teach the relocation code to handle physical
addressing for gen2/3, and we should then have universal support!

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Testcase: igt/gem_exec_reloc/basic-spin # snb
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501192945.22215-3-chris@chris-wilson.co.uk

drm/i915/gem: Use a single chained reloc batches for a single execbuf

As we can now keep chaining together a relocation batch to process any
number of relocations, we can keep building that relocation batch for
all of the target vma. This avoiding emitting a new request into the
ring for each target, consuming precious ring space and a potential
stall.

v2: Propagate the failure from submitting the relocation batch.

Testcase: igt/gem_exec_reloc/basic-wide-active
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501192945.22215-2-chris@chris-wilson.co.uk

drm/i915/gem: Use chained reloc batches

The ring is a precious resource: we anticipate to only use a few hundred
bytes for a request, and only try to reserve that before we start. If we
go beyond our guess in building the request, then instead of waiting at
the start of execbuf before we hold any locks or other resources, we
may trigger a wait inside a critical region. One example is in using gpu
relocations, where currently we emit a new MI_BB_START from the ring
every time we overflow a page of relocation entries. However, instead of
insert the command into the precious ring, we can chain the next page of
relocation entries as MI_BB_START from the end of the previous.

v2: Delay the emit_bb_start until after all the chained vma
synchronisation is complete. Since the buffer pool batches are idle, this
_should_ be a no-op, but one day we may some fancy async GPU bindings
for new vma!

v3: Use pool/batch consitently, once we start thinking in terms of the
batch vma, use batch->obj.
v4: Explain the magic number 4.

Tvrtko spotted that we lose propagation of the error for failing to
submit the relocation request; that's easier to fix up in the next
patch.

Testcase: igt/gem_exec_reloc/basic-many-active
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501192945.22215-1-chris@chris-wilson.co.uk

drm/i915: Implement vm_ops->access for gdb access into mmaps

gdb uses ptrace() to peek and poke bytes of the target's address space.
The driver must implement an vm_ops->access() handler or else gdb will
be unable to inspect the pointer and report it as out-of-bounds.
Worse than useless as it causes immediate suspicion of the valid GTT
pointer, distracting the poor programmer trying to find his bug.

v2: Write-protect readonly objects (Matthew).

Testcase: igt/gem_mmap_gtt/ptrace
Testcase: igt/gem_mmap_offset/ptrace
Suggested-by: Kristian H. Kristensen <hoegsberg@google.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: Kristian H. Kristensen <hoegsberg@google.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501145120.18830-1-chris@chris-wilson.co.uk

drm/i915/gt: Make timeslicing an explicit engine property

In order to allow userspace to rely on timeslicing to reorder their
batches, we must support preemption of those user batches. Declare
timeslicing as an explicit property that is a combination of having the
kernel support and HW support.

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 8ee36e048c98 ("drm/i915/execlists: Minimalistic timeslicing")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200501122249.12417-1-chris@chris-wilson.co.uk

drm/i915/pmu: Keep a reference to module while active

While a perf event is open, keep a reference to the module so we don't
remove the driver internals mid-sampling.

Testcase: igt/perf_pmu/module-unload
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430183324.23984-1-chris@chris-wilson.co.uk

drm/i915/gt: Move the batch buffer pool from the engine to the gt

Since the introduction of 'soft-rc6', we aim to park the device quickly
and that results in frequent idling of the whole device. Currently upon
idling we free the batch buffer pool, and so this renders the cache
ineffective for many workloads. If we want to have an effective cache of
recently allocated buffers available for reuse, we need to decouple that
cache from the engine powermanagement and make it timer based. As there
is no reason then to keep it within the engine (where it once made
retirement order easier to track), we can move it up the hierarchy to the
owner of the memory allocations.

v2: Hook up to debugfs/drop_caches to clear the cache on demand.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430111819.10262-2-chris@chris-wilson.co.uk

drm/i915: Update DRIVER_DATE to 20200430

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Merge tag 'gvt-next-2020-04-22' of https://github.com/intel/gvt-linux into drm-intel-next-queued

gvt-next-2020-04-22

- remove non-upstream xen support bits (Christoph)
- guest context shadow copy optimization (Yan)
- guest context tracking for shadow skip optimization (Yan)

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
From: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200422051230.GH11247@zhen-hp.sh.intel.com

drm/i915/selftests: Add tiled blits selftest

Extend coverage of the blitter client by exercising conversion to and
from tiled sources. In the process we perform spot checks to verify that
the tiling/detiling is being applied correctly, along with position
invariance of the tiling parameters.

Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200430064957.14942-1-chris@chris-wilson.co.uk

drm/i915/gt: Restore aggressive post-boost downclocking

We reduced the clocks slowly after a boost event based on the
observation that the smoothness of animations suffered. However, since
reducing the evalution intervals, we should be able to respond to the
rapidly fluctuating workload of a simple desktop animation and so
restore the more aggressive downclocking.

References: 2a8862d2f3da ("drm/i915: Reduce the RPS shock")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429205446.3259-6-chris@chris-wilson.co.uk

drm/i915/gt: Apply the aggressive downclocking to parking

We treat parking as a manual RPS timeout event, and downclock the GPU
for the next unpark and batch execution. However, having restored the
aggressive downclocking and observed that we have very light workloads
whose only interaction is through the manual parking events, carry over
the aggressive downclocking to the fake RPS events.

References: 21abf0bf168d ("drm/i915/gt: Treat idling as a RPS downclock event")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429205446.3259-5-chris@chris-wilson.co.uk

drm/i915/gt: Switch to manual evaluation of RPS

As with the realisation for soft-rc6, we respond to idling the engines
within microseconds, far faster than the response times for HW RC6 and
RPS. Furthermore, our fast parking upon idle, prevents HW RPS from
running for many desktop workloads, as the RPS evaluation intervals are
on the order of tens of milliseconds, but the typical workload is just a
couple of milliseconds, but yet we still need to determine the best
frequency for user latency versus power.

Recognising that the HW evaluation intervals are a poor fit, and that
they were deprecated [in bspec at least] from gen10, start to wean
ourselves off them and replace the EI with a timer and our accurate
busy-stats. The principle benefit of manually evaluating RPS intervals
is that we can be more responsive for better performance and powersaving
for both spiky workloads and steady-state.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1698
Fixes: 98479ada421a ("drm/i915/gt: Treat idling as a RPS downclock event")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429205446.3259-4-chris@chris-wilson.co.uk

drm/i915/gt: Track use of RPS interrupts in flags

Use the new intel_rps.flags field to store whether or not interrupts are
being used with RPS.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi@etezian.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429205446.3259-3-chris@chris-wilson.co.uk

drm/i915/gt: Move rps.enabled/active to flags

Pull the boolean intel_rps.enabled and intel_rps.active into a single
flags field, in preparation for more.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429205446.3259-2-chris@chris-wilson.co.uk

drm/i915/gt: Always enable busy-stats for execlists

In the near future, we will utilize the busy-stats on each engine to
approximate the C0 cycles of each, and use that as an input to a manual
RPS mechanism. That entails having busy-stats always enabled and so we
can remove the enable/disable routines and simplify the pmu setup. As a
consequence of always having the stats enabled, we can also show the
current active time via sysfs/engine/xcs/active_time_ns.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429205446.3259-1-chris@chris-wilson.co.uk

drm/i915/gt: Keep a no-frills swappable copy of the default context state

We need to keep the default context state around to instantiate new
contexts (aka golden rendercontext), and we also keep it pinned while
the engine is active so that we can quickly reset a hanging context.
However, the default contexts are large enough to merit keeping in
swappable memory as opposed to kernel memory, so we store them inside
shmemfs. Currently, we use the normal GEM objects to create the default
context image, but we can throw away all but the shmemfs file.

This greatly simplifies the tricky power management code which wants to
run underneath the normal GT locking, and we definitely do not want to
use any high level objects that may appear to recurse back into the GT.
Though perhaps the primary advantage of the complex GEM object is that
we aggressively cache the mapping, but here we are recreating the
vm_area everytime time we unpark. At the worst, we add a lightweight
cache, but first find a microbenchmark that is impacted.

Having started to create some utility functions to make working with
shmemfs objects easier, we can start putting them to wider use, where
GEM objects are overkill, such as storing persistent error state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429172429.6054-1-chris@chris-wilson.co.uk

drm/i915/selftests: fix error handling in __live_lrc_indirect_ctx_bb()

If intel_context_create() fails then it leads to an error pointer
dereference.  I shuffled things around to make error handling easier.

Fixes: 1dd47b54baea ("drm/i915: Add live selftests for indirect ctx batchbuffers")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429132425.GE815283@mwanda

drm/i915: Avoid dereferencing a dead context

Once the intel_context is closed, the GEM context may be freed and so
the link from intel_context.gem_context is invalid.

<3>[  219.782944] BUG: KASAN: use-after-free in intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<3>[  219.782996] Read of size 8 at addr ffff8881d7dff0b8 by task kworker/0:1/12

<4>[  219.783052] CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G     U            5.7.0-rc2-g1f3ffd7683d54-kasan_118+ #1
<4>[  219.783055] Hardware name: System manufacturer System Product Name/Z170 PRO GAMING, BIOS 3402 04/26/2017
<4>[  219.783105] Workqueue: events heartbeat [i915]
<4>[  219.783109] Call Trace:
<4>[  219.783113]  <IRQ>
<4>[  219.783119]  dump_stack+0x96/0xdb
<4>[  219.783177]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783182]  print_address_description.constprop.6+0x16/0x310
<4>[  219.783239]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783295]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783300]  __kasan_report+0x137/0x190
<4>[  219.783359]  ? intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783366]  kasan_report+0x32/0x50
<4>[  219.783426]  intel_engine_coredump_alloc+0x1bc3/0x2250 [i915]
<4>[  219.783481]  execlists_reset+0x39c/0x13d0 [i915]
<4>[  219.783494]  ? mark_held_locks+0x9e/0xe0
<4>[  219.783546]  ? execlists_hold+0xfc0/0xfc0 [i915]
<4>[  219.783551]  ? lockdep_hardirqs_on+0x348/0x5f0
<4>[  219.783557]  ? _raw_spin_unlock_irqrestore+0x34/0x60
<4>[  219.783606]  ? execlists_submission_tasklet+0x118/0x3a0 [i915]
<4>[  219.783615]  tasklet_action_common.isra.14+0x13b/0x410
<4>[  219.783623]  ? __do_softirq+0x1e4/0x9a7
<4>[  219.783630]  __do_softirq+0x226/0x9a7
<4>[  219.783643]  do_softirq_own_stack+0x2a/0x40
<4>[  219.783647]  </IRQ>
<4>[  219.783692]  ? heartbeat+0x3e2/0x10f0 [i915]
<4>[  219.783696]  do_softirq.part.13+0x49/0x50
<4>[  219.783700]  __local_bh_enable_ip+0x1a2/0x1e0
<4>[  219.783748]  heartbeat+0x409/0x10f0 [i915]
<4>[  219.783801]  ? __live_idle_pulse+0x9f0/0x9f0 [i915]
<4>[  219.783806]  ? lock_acquire+0x1ac/0x8a0
<4>[  219.783811]  ? process_one_work+0x811/0x1870
<4>[  219.783827]  ? rcu_read_lock_sched_held+0x9c/0xd0
<4>[  219.783832]  ? rcu_read_lock_bh_held+0xb0/0xb0
<4>[  219.783836]  ? _raw_spin_unlock_irq+0x1f/0x40
<4>[  219.783845]  process_one_work+0x8ca/0x1870
<4>[  219.783848]  ? lock_acquire+0x1ac/0x8a0
<4>[  219.783852]  ? worker_thread+0x1d0/0xb80
<4>[  219.783864]  ? pwq_dec_nr_in_flight+0x2c0/0x2c0
<4>[  219.783870]  ? do_raw_spin_lock+0x129/0x290
<4>[  219.783886]  worker_thread+0x82/0xb80
<4>[  219.783895]  ? __kthread_parkme+0xaf/0x1b0
<4>[  219.783902]  ? process_one_work+0x1870/0x1870
<4>[  219.783906]  kthread+0x34e/0x420
<4>[  219.783911]  ? kthread_create_on_node+0xc0/0xc0
<4>[  219.783918]  ret_from_fork+0x3a/0x50

<3>[  219.783950] Allocated by task 1264:
<4>[  219.783975]  save_stack+0x19/0x40
<4>[  219.783978]  __kasan_kmalloc.constprop.3+0xa0/0xd0
<4>[  219.784029]  i915_gem_create_context+0xa2/0xab8 [i915]
<4>[  219.784081]  i915_gem_context_create_ioctl+0x1fa/0x450 [i915]
<4>[  219.784085]  drm_ioctl_kernel+0x1d8/0x270
<4>[  219.784088]  drm_ioctl+0x676/0x930
<4>[  219.784092]  ksys_ioctl+0xb7/0xe0
<4>[  219.784096]  __x64_sys_ioctl+0x6a/0xb0
<4>[  219.784100]  do_syscall_64+0x94/0x530
<4>[  219.784103]  entry_SYSCALL_64_after_hwframe+0x49/0xb3

<3>[  219.784120] Freed by task 12:
<4>[  219.784141]  save_stack+0x19/0x40
<4>[  219.784145]  __kasan_slab_free+0x130/0x180
<4>[  219.784148]  kmem_cache_free_bulk+0x1bd/0x500
<4>[  219.784152]  kfree_rcu_work+0x1d8/0x890
<4>[  219.784155]  process_one_work+0x8ca/0x1870
<4>[  219.784158]  worker_thread+0x82/0xb80
<4>[  219.784162]  kthread+0x34e/0x420
<4>[  219.784165]  ret_from_fork+0x3a/0x50

Fixes: 2e46a2a0b014 ("drm/i915: Use explicit flag to mark unreachable intel_context")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428090255.10035-1-chris@chris-wilson.co.uk

drm/i915/gt: Avoid uninitialized use of rpcurupei in frequency_show

When building with clang + -Wuninitialized:

drivers/gpu/drm/i915/gt/debugfs_gt_pm.c:407:7: warning: variable
'rpcurupei' is uninitialized when used here [-Wuninitialized]
                           rpcurupei,
                           ^~~~~~~~~
drivers/gpu/drm/i915/gt/debugfs_gt_pm.c:304:16: note: initialize the
variable 'rpcurupei' to silence this warning
                u32 rpcurupei, rpcurup, rpprevup;
                             ^
                              = 0
1 warning generated.

rpupei is assigned twice; based on the second argument to
intel_uncore_read, it seems this one should have been assigned to
rpcurupei.

Fixes: 9c878557b1eb ("drm/i915/gt: Use the RPM config register to determine clk frequencies")
Link: https://github.com/ClangBuiltLinux/linux/issues/1016
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200429030051.920203-1-natechancellor@gmail.com

drm/i915/execlists: Verify we don't submit two identical CCIDs

Check that we do not submit two contexts into ELSP with the same CCID
[upper portion of the descriptor].

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1793
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428184751.11257-3-chris@chris-wilson.co.uk

drm/i915/execlists: Track inflight CCID

The presumption is that by using a circular counter that is twice as
large as the maximum ELSP submission, we would never reuse the same CCID
for two inflight contexts.

However, if we continually preempt an active context such that it always
remains inflight, it can be resubmitted with an arbitrary number of
paired contexts. As each of its paired contexts will use a new CCID,
eventually it will wrap and submit two ELSP with the same CCID.

Rather than use a simple circular counter, switch over to a small bitmap
of inflight ids so we can avoid reusing one that is still potentially
active.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1796
Fixes: 2935ed5339c4 ("drm/i915: Remove logical HW ID")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428184751.11257-2-chris@chris-wilson.co.uk

drm/i915/execlists: Avoid reusing the same logical CCID

The bspec is confusing on the nature of the upper 32bits of the LRC
descriptor. Once upon a time, it said that it uses the upper 32b to
decide if it should perform a lite-restore, and so we must ensure that
each unique context submitted to HW is given a unique CCID [for the
duration of it being on the HW]. Currently, this is achieved by using
a small circular tag, and assigning every context submitted to HW a
new id. However, this tag is being cleared on repinning an inflight
context such that we end up re-using the 0 tag for multiple contexts.

To avoid accidentally clearing the CCID in the upper 32bits of the LRC
descriptor, split the descriptor into two dwords so we can update the
GGTT address separately from the CCID.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1796
Fixes: 2935ed5339c4 ("drm/i915: Remove logical HW ID")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.5+
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428184751.11257-1-chris@chris-wilson.co.uk

drm/i915/tgl: Wa_14011059788

Reflect recent Bspec changes

v2: fix whitespace, typo

Signed-off-by: Matt Atwood <matthew.s.atwood@intel.com>
Reviewed-by: Radhakrishna Sripada <Radhakrishna.sripada@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200415193535.14597-1-matthew.s.atwood@intel.com

drm/i915/selftests: Tweak the tolerance for clock ticks to 12.5%

Give a small bump for our tolerance on comparing the expected vs
measured clock ticks/time from 10% to 12.5% to accommodate a bad result
on Sandybridge that was off by 10.3%. Hopefully, that is the worst we
will see.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1802
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428114307.5153-1-chris@chris-wilson.co.uk

drm/i915/gt: fix spelling mistake "evalution" -> "evaluation"

There is a spelling mistaking in a pr_notice message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200428084920.1035125-1-colin.king@canonical.com

drm/i915: Use proper fault mask in interrupt postinstall too

The IRQ postinstall handling had open-coded pipe fault mask selection
that never got updated for gen11.  Switch it to use
gen8_de_pipe_fault_mask() to ensure we don't miss updates for new
platforms.

Cc: José Roberto de Souza <jose.souza@intel.com>
Fixes: d506a65d56fd ("drm/i915: Catch GTT fault errors for gen11+ planes")
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424231423.4065231-1-matthew.d.roper@intel.com
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

drm/i915/gt: Fix up clock frequency

The bspec lists both the clock frequency and the effective interval. The
interval corresponds to observed behaviour, so adjust the frequency to
match.

v2: Mika rightfully asked if we could measure the clock frequency from a
selftest.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200427154554.12736-1-chris@chris-wilson.co.uk

drm/i915/gt: Sanitize GT first

We see that if the HW doesn't actually sleep, the HW may eat the poison
we set in its write-only HWSP during sanitize:

  intel_gt_resume.part.8: 0000:00:02.0
  __gt_unpark: 0000:00:02.0
  gt_sanitize: 0000:00:02.0 force:yes
  process_csb: 0000:00:02.0 vcs0: cs-irq head=5, tail=90
  process_csb: 0000:00:02.0 vcs0: csb[0]: status=0x5a5a5a5a:0x5a5a5a5a
  assert_pending_valid: Nothing pending for promotion!

The CS TAIL pointer should have been reset by reset_csb_pointers(), so
in this case it is likely that we have read back from the CPU cache and
so we must clflush our control over that page. In doing so, push the
sanitisation to the start of the GT sequence so that our poisoning is
assuredly before we start talking to the HW.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1794
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200427084000.10999-1-chris@chris-wilson.co.uk

drm/i915/gt: Check cacheline is valid before acquiring

The hwsp_cacheline pointer from i915_request is very, very flimsy. The
i915_request.timeline (and the hwsp_cacheline) are lost upon retiring
(after an RCU grace). Therefore we need to confirm that once we have the
right pointer for the cacheline, it is not in the process of being
retired and disposed of before we attempt to acquire a reference to the
cacheline.

<3>[  547.208237] BUG: KASAN: use-after-free in active_debug_hint+0x6a/0x70 [i915]
<3>[  547.208366] Read of size 8 at addr ffff88822a0d2710 by task gem_exec_parall/2536

<4>[  547.208547] CPU: 3 PID: 2536 Comm: gem_exec_parall Tainted: G     U            5.7.0-rc2-ged7a286b5d02d-kasan_117+ #1
<4>[  547.208556] Hardware name: Dell Inc. XPS 13 9350/, BIOS 1.4.12 11/30/2016
<4>[  547.208564] Call Trace:
<4>[  547.208579]  dump_stack+0x96/0xdb
<4>[  547.208707]  ? active_debug_hint+0x6a/0x70 [i915]
<4>[  547.208719]  print_address_description.constprop.6+0x16/0x310
<4>[  547.208841]  ? active_debug_hint+0x6a/0x70 [i915]
<4>[  547.208963]  ? active_debug_hint+0x6a/0x70 [i915]
<4>[  547.208975]  __kasan_report+0x137/0x190
<4>[  547.209106]  ? active_debug_hint+0x6a/0x70 [i915]
<4>[  547.209127]  kasan_report+0x32/0x50
<4>[  547.209257]  ? i915_gemfs_fini+0x40/0x40 [i915]
<4>[  547.209376]  active_debug_hint+0x6a/0x70 [i915]
<4>[  547.209389]  debug_print_object+0xa7/0x220
<4>[  547.209405]  ? lockdep_hardirqs_on+0x348/0x5f0
<4>[  547.209426]  debug_object_assert_init+0x297/0x430
<4>[  547.209449]  ? debug_object_free+0x360/0x360
<4>[  547.209472]  ? lock_acquire+0x1ac/0x8a0
<4>[  547.209592]  ? intel_timeline_read_hwsp+0x4f/0x840 [i915]
<4>[  547.209737]  ? i915_active_acquire_if_busy+0x66/0x120 [i915]
<4>[  547.209861]  i915_active_acquire_if_busy+0x66/0x120 [i915]
<4>[  547.209990]  ? __live_alloc.isra.15+0xc0/0xc0 [i915]
<4>[  547.210005]  ? rcu_read_lock_sched_held+0xd0/0xd0
<4>[  547.210017]  ? print_usage_bug+0x580/0x580
<4>[  547.210153]  intel_timeline_read_hwsp+0xbc/0x840 [i915]
<4>[  547.210284]  __emit_semaphore_wait+0xd5/0x480 [i915]
<4>[  547.210415]  ? i915_fence_get_timeline_name+0x110/0x110 [i915]
<4>[  547.210428]  ? lockdep_hardirqs_on+0x348/0x5f0
<4>[  547.210442]  ? _raw_spin_unlock_irq+0x2a/0x40
<4>[  547.210567]  ? __await_execution.constprop.51+0x2e0/0x570 [i915]
<4>[  547.210706]  i915_request_await_dma_fence+0x8f7/0xc70 [i915]

Fixes: 85bedbf191e8 ("drm/i915/gt: Eliminate the trylock for reading a timeline's hwsp")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: <stable@vger.kernel.org> # v5.6+
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200427093038.29219-1-chris@chris-wilson.co.uk

drm/i915/execlists: Check preempt-timeout target before submit_ports

We evaluate *active, which is a pointer into execlists->inflight[]
during dequeue to decide how long a preempt-timeout we need to apply.
However, as soon as we do the submit_ports, the HW may send its ACK
interrupt causing us to promote execlists->pending[] tp
execlists->inflight[], overwriting the value of *active. We know *active
is only stable until we submit (as we only submit when there is no
pending promotion).

[   16.102328] BUG: KCSAN: data-race in execlists_dequeue+0x1449/0x1600 [i915]
[   16.102356]
[   16.102375] race at unknown origin, with read to 0xffff8881e9500488 of 8 bytes by task 429 on cpu 1:
[   16.102780]  execlists_dequeue+0x1449/0x1600 [i915]
[   16.103160]  __execlists_submission_tasklet+0x48/0x60 [i915]
[   16.103540]  execlists_submit_request+0x38e/0x3c0 [i915]
[   16.103940]  submit_notify+0x8f/0xc0 [i915]
[   16.104308]  __i915_sw_fence_complete+0x61/0x420 [i915]
[   16.104683]  i915_sw_fence_complete+0x58/0x80 [i915]
[   16.105054]  i915_sw_fence_commit+0x16/0x20 [i915]
[   16.105457]  __i915_request_queue+0x60/0x70 [i915]
[   16.105843]  i915_gem_do_execbuffer+0x2d6b/0x4230 [i915]
[   16.106227]  i915_gem_execbuffer2_ioctl+0x2b0/0x580 [i915]
[   16.106257]  drm_ioctl_kernel+0xe9/0x130
[   16.106279]  drm_ioctl+0x27d/0x45e
[   16.106311]  ksys_ioctl+0x89/0xb0
[   16.106336]  __x64_sys_ioctl+0x42/0x60
[   16.106370]  do_syscall_64+0x6e/0x2c0
[   16.106397]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200426094231.21995-1-chris@chris-wilson.co.uk

drm/i915: re-disable -Wframe-address

The top level Makefile disables this warning. When building an
i386_defconfig with Clang, this warning is triggered a whole bunch via
includes of headers from perf.

Link: https://github.com/ClangBuiltLinux/continuous-integration/pull/182
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200426214215.139435-1-ndesaulniers@google.com

drm/i915: Use indirect ctx bb to mend CMD_BUF_CCTL

Use indirect ctx bb to load cmd buffer control value
from context image to avoid corruption.

v2: add to lrc layout (Chris)
v3: end to a cacheline (Chris)
v4: add to lrc fixed (Chris)
v5: value in offset+1

Testcase: igt/i915_selftest/gt_lrc
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424230632.30333-1-mika.kuoppala@linux.intel.com

drm/i915: Add live selftests for indirect ctx batchbuffers

Indirect ctx batchbuffers are a hw feature of which
batch can be run, by hardware, during context restoration stage.
Driver can setup a batchbuffer and also an offset into the
context image. When context image is marshalled from
memory to registers, and when the offset from the start of
context register state is equal of what driver pre-determined,
batch will run. So one can manipulate context restoration
process at cacheline granularity, given some limitations,
as you need to have rudimentaries in place before you can
run a batch.

Add selftest which will write the ring start register
to a canary spot. This will test that hardware will run a
batchbuffer for the context in question.

v2: request wait fix, naming (Chris)
v3: test order (Chris)
v4: rebase

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424214841.28076-3-mika.kuoppala@linux.intel.com

drm/i915: Add per ctx batchbuffer wa for timestamp

Restoration of a previous timestamp can collide
with updating the timestamp, causing a value corruption.

Combat this issue by using indirect ctx bb to
modify the context image during restoring process.

We can preload value into scratch register. From which
we then do the actual write with LRR. LRR is faster and
thus less error prone as probability of race drops.

v2: tidying (Chris)
v3: lrr for all engines
v4: grp
v5: reg bit
v6: wa_bb_offset, virtual engines (Chris)

References: HSDES#16010904313
Testcase: igt/i915_selftest/gt_lrc
Suggested-by: Joseph Koston <joseph.koston@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424230546.30271-1-mika.kuoppala@linux.intel.com

drm/i915: Add engine scratch register to live_lrc_fixed

General purpose registers are per engine and
in a fixed location. Add to live_lrc_fixed.

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424214841.28076-1-mika.kuoppala@linux.intel.com

drm/i915: Drop rq->ring->vma peeking from error capture

We only hold the active spinlock while dumping the error state, and this
does not prevent another thread from retiring the request -- as it is
quite possible that despite us capturing the current state, the GPU has
completed the request. As such, it is dangerous to dereference state
below the request as it may already be freed, and the simplest way to
avoid the danger is not include it in the error state.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/1788
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424191410.27570-1-chris@chris-wilson.co.uk

drm/i915/gt: Use the RPM config register to determine clk frequencies

For many configuration details within RC6 and RPS we are programming
intervals for the internal clocks. From gen11, these clocks are
configuration via the RPM_CONFIG and so for convenience, we would like
to convert to/from more natural units (ns).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200424162805.25920-2-chris@chris-wilson.co.uk