Use types of more appropriate size in struct
intel_watermark_params to save 512 bytes of .rodata.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>

unsigned long is too wide - use smaller types in
struct cxsr_latency to save 800-something bytes of .rodata.

v2: All data even fits in u16 for even more saving. (Ville Syrjala)
v3: Move bitfields to the end of the struct. (Joonas Lahtinen)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>

With the previous code we were only recomputing the DDB partitioning
for the CRTCs included in the atomic commit, so any other active CRTCs
would end up having their DDB registers zeroed. In this patch we make
sure that the computed state starts as a copy of the current
partitioning, and then we only zero the DDBs that we're actually
going to recompute.

How to reproduce the bug:
  1 - Enable the primary plane on pipe A
  2 - Enable the primary plane on pipe B
  3 - Enable the cursor or sprite plane on pipe A

Step 3 will zero the DDB partitioning for pipe B since it's not
included in the commit that enabled the cursor or sprite for pipe A.

I expect this to fix many FIFO underrun problems on gen9+.

v2:
  - Mention the cursor on the steps to reproduce the problem (Paulo).
  - Add Testcase tag provided by Maarten (Maarten).

Testcase: kms_cursor_legacy.cursorA-vs-flipB-atomic-transitions
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96226
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96828
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97450
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97596
Bugzilla: https://www.phoronix.com/scan.php?page=news_item&px=Intel-Skylake-Multi-Screen-Woes
Cc: stable@vger.kernel.org
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NLyude <cpaul@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1475602652-17326-1-git-send-email-paulo.r.zanoni@intel.com

We were previously adding all the planes owned by the CRTC even when
the ddb partitioning didn't change for them. As a consequence, a lot
of functions were being called when we were just moving the cursor
around the screen, such as skylake_update_primary_plane().

This was causing flickering on the primary plane when moving the
cursor. I'm not 100% sure which operation caused the flickering, but
we were writing to a lot of registers, so it could be any of these
writes. With this patch, just moving the mouse won't add the primary
plane to the commit since it won't trigger a change in DDB
partitioning.

v2: Use skl_ddb_entry_equal() (Lyude).
v3: Change Reported-and-bisected-by: to Reported-by: for checkpatch

Fixes: 05a76d3d ("drm/i915/skl: Ensure pipes with changed wms get added to the state")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97888
Cc: Mike Lothian <mike@fireburn.co.uk>
Cc: stable@vger.kernel.org
Reported-by: NMike Lothian <mike@fireburn.co.uk>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NLyude <cpaul@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1475177808-29955-1-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 7f60e200)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

We forgot the "res_blocks += y_tile_minimum" that's described on step
V of our documentation.

Again, this should only affect the Y tiling cases.

It looks like the relevant code was introduced in 0fda6568, but
there's always the possibility that it matched our specification when
it was introduced, and then the specification changed while the code
stayed the same. So we can't really say this was a regression, but
let's try to add a "Fixes" tag anyway to help backporting.

v2: Try to add a "Fixes" tag (Maarten).

Fixes: 0fda6568 ("drm/i915/skl: Update watermarks for Y tiling")
Cc: stable@vger.kernel.org
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-8-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 75676ed4)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The confusing thing is that plane_blocks_per_line is listed as part of
the method 2 calculation but is also used for other things. We
calculated it in two different places and different ways: one inside
skl_wm_method2() and the other inside skl_compute_plane_wm(). The
skl_wm_method2() implementation is the one that matches the
specification.

With this patch we fix the skl_compute_plane_wm() calculation and just
pass it as a parameter to skl_wm_method2(). We also take care to not
modify the value of plane_bytes_per_line since we're going to rely on
it having a correct value in later patches.

This should affect the watermarks for Linear and Y-tiled.

From my analysis, it looks like the two plane_blocks_per_line
variables got out of sync on 0fda6568, but we can't really say
that commit was a regression, it looks like just an incomplete fix.
There's always the possibility that 0fda6568 matched our
specification at that time, and then later the specification changed.

v2: Try to add a "Fixes" tag (Maarten).

Fixes: 0fda6568 ("drm/i915/skl: Update watermarks for Y tiling")
Cc: stable@vger.kernel.org
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-7-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 7a1a8aed)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

During watermarks calculations, this value is used in 3 different
places. Only one of them was not using a hardcoded 4. Move the code up
so everybody can benefit from the actual value.

This should only help on situations with Y tiling + 90/270 rotation +
1 or 2 bpp or NV12.

Cc: stable@vger.kernel.org
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-6-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 1186fa85)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Bspec says:
  "The mailbox response data may not account for memory read latency.
   If the mailbox response data for level 0 is 0us, add 2 microseconds
   to the result for each valid level."

This means we should only do the +2 in case wm[0] == 0, not always.

So split the sanitizing implementation from the WA implementation and
fix the WA implementation.

v2: Add Fixes tag (Maarten).

Fixes: 367294be ("drm/i915/gen9: Add 2us read latency to WM level")
Cc: stable@vger.kernel.org
Cc: Vandana Kannan <vandana.kannan@intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-5-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 0727e40a)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

According to BSpec, it's the "core CPUs" that need the code, which
means SKL and KBL, but not BXT.

I don't have a KBL to test this patch on it.

v2: Only SKL should have I915_SAGV_NOT_CONTROLLED.

Cc: stable@vger.kernel.org
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-4-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 6e3100ec)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

And use it to move knowledge about the SAGV-supporting platforms from
the callers to the SAGV code.

We'll add more platforms to intel_has_sagv(), so IMHO it makes more
sense to move all this to a single function instead of patching all
the callers every time we add SAGV support to a new platform.

v2: Move I915_SAGV_NOT_CONTROLLED to the new function (Lyude).

Cc: stable@vger.kernel.org
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-3-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 56feca91)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The plan is to introduce intel_has_sagv() and then use it to discover
which platforms actually support it.

I thought about keeping the functions with their current skl names,
but found two problems: (i) skl_has_sagv() would become a very
confusing name, and (ii) intel_atomic_commit_tail() doesn't seem to be
calling any functions whose name start with a platform name, so the
"intel_" naming scheme seems make more sense than the "firstplatorm_"
naming scheme here.

Cc: stable@vger.kernel.org
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-2-git-send-email-paulo.r.zanoni@intel.com
(cherry picked from commit 16dcdc4e)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Fix sparse warning:

drivers/gpu/drm/i915/intel_pm.c:3970:1: warning: symbol
'skl_ddb_add_affected_planes' was not declared. Should it be static?

Fixes: 7f60e200 ("drm/i915/gen9: only add the planes actually affected by ddb changes")
Cc: Lyude <cpaul@redhat.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1475573357-30562-1-git-send-email-jani.nikula@intel.com

We were previously adding all the planes owned by the CRTC even when
the ddb partitioning didn't change for them. As a consequence, a lot
of functions were being called when we were just moving the cursor
around the screen, such as skylake_update_primary_plane().

This was causing flickering on the primary plane when moving the
cursor. I'm not 100% sure which operation caused the flickering, but
we were writing to a lot of registers, so it could be any of these
writes. With this patch, just moving the mouse won't add the primary
plane to the commit since it won't trigger a change in DDB
partitioning.

v2: Use skl_ddb_entry_equal() (Lyude).
v3: Change Reported-and-bisected-by: to Reported-by: for checkpatch

Fixes: 05a76d3d ("drm/i915/skl: Ensure pipes with changed wms get added to the state")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97888
Cc: Mike Lothian <mike@fireburn.co.uk>
Cc: stable@vger.kernel.org
Reported-by: NMike Lothian <mike@fireburn.co.uk>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NLyude <cpaul@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1475177808-29955-1-git-send-email-paulo.r.zanoni@intel.com

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474891672-23414-1-git-send-email-jani.nikula@intel.com

Now that this code is part of the compute stage we can return -EINVAL
to prevent the modeset instead of giving a WARN and trying anyway.

v2:
 - Fix typo (Paul Menzel).
 - Add MISSING_CASE() (Ville, Maarten).
Reported-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-10-git-send-email-paulo.r.zanoni@intel.com

This should affect linear and X tiled planes on really small htotal
cases. It doesn't seem to be a very feasible case, but let's implement
it since it's on the specification and it's better to have it and
never need than not have it and realize we needed it.
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-9-git-send-email-paulo.r.zanoni@intel.com

We forgot the "res_blocks += y_tile_minimum" that's described on step
V of our documentation.

Again, this should only affect the Y tiling cases.

It looks like the relevant code was introduced in 0fda6568, but
there's always the possibility that it matched our specification when
it was introduced, and then the specification changed while the code
stayed the same. So we can't really say this was a regression, but
let's try to add a "Fixes" tag anyway to help backporting.

v2: Try to add a "Fixes" tag (Maarten).

Fixes: 0fda6568 ("drm/i915/skl: Update watermarks for Y tiling")
Cc: stable@vger.kernel.org
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-8-git-send-email-paulo.r.zanoni@intel.com

The confusing thing is that plane_blocks_per_line is listed as part of
the method 2 calculation but is also used for other things. We
calculated it in two different places and different ways: one inside
skl_wm_method2() and the other inside skl_compute_plane_wm(). The
skl_wm_method2() implementation is the one that matches the
specification.

With this patch we fix the skl_compute_plane_wm() calculation and just
pass it as a parameter to skl_wm_method2(). We also take care to not
modify the value of plane_bytes_per_line since we're going to rely on
it having a correct value in later patches.

This should affect the watermarks for Linear and Y-tiled.

From my analysis, it looks like the two plane_blocks_per_line
variables got out of sync on 0fda6568, but we can't really say
that commit was a regression, it looks like just an incomplete fix.
There's always the possibility that 0fda6568 matched our
specification at that time, and then later the specification changed.

v2: Try to add a "Fixes" tag (Maarten).

Fixes: 0fda6568 ("drm/i915/skl: Update watermarks for Y tiling")
Cc: stable@vger.kernel.org
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-7-git-send-email-paulo.r.zanoni@intel.com

During watermarks calculations, this value is used in 3 different
places. Only one of them was not using a hardcoded 4. Move the code up
so everybody can benefit from the actual value.

This should only help on situations with Y tiling + 90/270 rotation +
1 or 2 bpp or NV12.

Cc: stable@vger.kernel.org
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-6-git-send-email-paulo.r.zanoni@intel.com

Bspec says:
  "The mailbox response data may not account for memory read latency.
   If the mailbox response data for level 0 is 0us, add 2 microseconds
   to the result for each valid level."

This means we should only do the +2 in case wm[0] == 0, not always.

So split the sanitizing implementation from the WA implementation and
fix the WA implementation.

v2: Add Fixes tag (Maarten).

Fixes: 367294be ("drm/i915/gen9: Add 2us read latency to WM level")
Cc: stable@vger.kernel.org
Cc: Vandana Kannan <vandana.kannan@intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-5-git-send-email-paulo.r.zanoni@intel.com

According to BSpec, it's the "core CPUs" that need the code, which
means SKL and KBL, but not BXT.

I don't have a KBL to test this patch on it.

v2: Only SKL should have I915_SAGV_NOT_CONTROLLED.

Cc: stable@vger.kernel.org
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-4-git-send-email-paulo.r.zanoni@intel.com

And use it to move knowledge about the SAGV-supporting platforms from
the callers to the SAGV code.

We'll add more platforms to intel_has_sagv(), so IMHO it makes more
sense to move all this to a single function instead of patching all
the callers every time we add SAGV support to a new platform.

v2: Move I915_SAGV_NOT_CONTROLLED to the new function (Lyude).

Cc: stable@vger.kernel.org
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-3-git-send-email-paulo.r.zanoni@intel.com

The plan is to introduce intel_has_sagv() and then use it to discover
which platforms actually support it.

I thought about keeping the functions with their current skl names,
but found two problems: (i) skl_has_sagv() would become a very
confusing name, and (ii) intel_atomic_commit_tail() doesn't seem to be
calling any functions whose name start with a platform name, so the
"intel_" naming scheme seems make more sense than the "firstplatorm_"
naming scheme here.

Cc: stable@vger.kernel.org
Reviewed-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474578035-424-2-git-send-email-paulo.r.zanoni@intel.com

Pre-production hardware is not supported.
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/d28d21ceddeec226b5d1a20a7382bee9a72709a4.1474034059.git.jani.nikula@intel.com

Adding the ddb size into the devide info will avoid
platform checks while computing wm.

v2: Added comment and WARN_ON if ddb size is zero.(Jani)
v3: Added WARN_ON at the right place.(Jani)
Suggested-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: NDeepak M <m.deepak@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473931870-7724-1-git-send-email-m.deepak@intel.com

Access to intel_init_emon() is strictly ordered by gt_powersave, using
struct_mutex around it is overkill (and will conflict with the caller
holding struct_mutex themselves).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160909131201.16673-8-chris@chris-wilson.co.uk

According to the CI test machines, SNB also uses the
GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE value to report a bad
GEN6_PCODE_MIN_FREQ_TABLE request.

[  157.744641] WARNING: CPU: 5 PID: 9238 at
drivers/gpu/drm/i915/intel_pm.c:7760 sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744642] Missing switch case (16) in gen6_check_mailbox_status
[  157.744642] Modules linked in: snd_hda_intel i915 ax88179_178a usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me lpc_ich snd_pcm mei broadcom bcm_phy_lib tg3 ptp pps_core [last unloaded: vgem]
[  157.744658] CPU: 5 PID: 9238 Comm: drv_hangman Tainted: G     U  W 4.8.0-rc3-CI-CI_DRM_1589+ #1
[  157.744658] Hardware name: Dell Inc. XPS 8300  /0Y2MRG, BIOS A06 10/17/2011
[  157.744659]  0000000000000000 ffff88011f093a98 ffffffff81426415 ffff88011f093ae8
[  157.744662]  0000000000000000 ffff88011f093ad8 ffffffff8107d2a6 00001e50810d3c9f
[  157.744663]  ffff880128680000 0000000000000008 0000000000000000 ffff88012868a650
[  157.744665] Call Trace:
[  157.744669]  [<ffffffff81426415>] dump_stack+0x67/0x92
[  157.744672]  [<ffffffff8107d2a6>] __warn+0xc6/0xe0
[  157.744673]  [<ffffffff8107d30a>] warn_slowpath_fmt+0x4a/0x50
[  157.744685]  [<ffffffffa0029831>] sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744697]  [<ffffffffa002a88a>] intel_enable_gt_powersave+0x64a/0x1330 [i915]
[  157.744712]  [<ffffffffa006b4cb>] ? i9xx_emit_request+0x1b/0x80 [i915]
[  157.744725]  [<ffffffffa0055ed3>] __i915_add_request+0x1e3/0x370 [i915]
[  157.744738]  [<ffffffffa00428bd>] i915_gem_do_execbuffer.isra.16+0xced/0x1b80 [i915]
[  157.744740]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744752]  [<ffffffffa0043b72>] i915_gem_execbuffer2+0xc2/0x2a0 [i915]
[  157.744753]  [<ffffffff815485b7>] drm_ioctl+0x207/0x4c0
[  157.744765]  [<ffffffffa0043ab0>] ? i915_gem_execbuffer+0x360/0x360 [i915]
[  157.744767]  [<ffffffff810ea4ad>] ?  debug_lockdep_rcu_enabled+0x1d/0x20
[  157.744769]  [<ffffffff811fe09e>] do_vfs_ioctl+0x8e/0x680
[  157.744770]  [<ffffffff811a2377>] ? __might_fault+0x87/0x90
[  157.744771]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744773]  [<ffffffff810d3df2>] ?  trace_hardirqs_on_caller+0x122/0x1b0
[  157.744774]  [<ffffffff811fe6cc>] SyS_ioctl+0x3c/0x70
[  157.744776]  [<ffffffff8180fe69>] entry_SYSCALL_64_fastpath+0x1c/0xac

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97491
Fixes: 87660502 ("drm/i915/gen6+: Interpret mailbox error flags")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Lyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://patchwork.freedesktop.org/patch/msgid/20160826105926.3413-1-chris@chris-wilson.co.ukAcked-by: NMika Kuoppala <mika.kuoppala@intel.com>
(cherry picked from commit 7850d1c3)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Move all slice/subslice/eu related properties to the sseu_dev_info
struct.

No functional change.

v2:
- s/info/sseu/ based on the new struct name. (Ben)

Reviewed-by: Robert Bragg <robert@sixbynine.org> (v1)
Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com> (v1)
Tested-by: Ben Widawsky <benjamin.widawsky@intel.com> (v1)
Signed-off-by: NImre Deak <imre.deak@intel.com>

According to the CI test machines, SNB also uses the
GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE value to report a bad
GEN6_PCODE_MIN_FREQ_TABLE request.

[  157.744641] WARNING: CPU: 5 PID: 9238 at
drivers/gpu/drm/i915/intel_pm.c:7760 sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744642] Missing switch case (16) in gen6_check_mailbox_status
[  157.744642] Modules linked in: snd_hda_intel i915 ax88179_178a usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core mei_me lpc_ich snd_pcm mei broadcom bcm_phy_lib tg3 ptp pps_core [last unloaded: vgem]
[  157.744658] CPU: 5 PID: 9238 Comm: drv_hangman Tainted: G     U  W 4.8.0-rc3-CI-CI_DRM_1589+ #1
[  157.744658] Hardware name: Dell Inc. XPS 8300  /0Y2MRG, BIOS A06 10/17/2011
[  157.744659]  0000000000000000 ffff88011f093a98 ffffffff81426415 ffff88011f093ae8
[  157.744662]  0000000000000000 ffff88011f093ad8 ffffffff8107d2a6 00001e50810d3c9f
[  157.744663]  ffff880128680000 0000000000000008 0000000000000000 ffff88012868a650
[  157.744665] Call Trace:
[  157.744669]  [<ffffffff81426415>] dump_stack+0x67/0x92
[  157.744672]  [<ffffffff8107d2a6>] __warn+0xc6/0xe0
[  157.744673]  [<ffffffff8107d30a>] warn_slowpath_fmt+0x4a/0x50
[  157.744685]  [<ffffffffa0029831>] sandybridge_pcode_write+0x141/0x200 [i915]
[  157.744697]  [<ffffffffa002a88a>] intel_enable_gt_powersave+0x64a/0x1330 [i915]
[  157.744712]  [<ffffffffa006b4cb>] ? i9xx_emit_request+0x1b/0x80 [i915]
[  157.744725]  [<ffffffffa0055ed3>] __i915_add_request+0x1e3/0x370 [i915]
[  157.744738]  [<ffffffffa00428bd>] i915_gem_do_execbuffer.isra.16+0xced/0x1b80 [i915]
[  157.744740]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744752]  [<ffffffffa0043b72>] i915_gem_execbuffer2+0xc2/0x2a0 [i915]
[  157.744753]  [<ffffffff815485b7>] drm_ioctl+0x207/0x4c0
[  157.744765]  [<ffffffffa0043ab0>] ? i915_gem_execbuffer+0x360/0x360 [i915]
[  157.744767]  [<ffffffff810ea4ad>] ?  debug_lockdep_rcu_enabled+0x1d/0x20
[  157.744769]  [<ffffffff811fe09e>] do_vfs_ioctl+0x8e/0x680
[  157.744770]  [<ffffffff811a2377>] ? __might_fault+0x87/0x90
[  157.744771]  [<ffffffff811a232e>] ? __might_fault+0x3e/0x90
[  157.744773]  [<ffffffff810d3df2>] ?  trace_hardirqs_on_caller+0x122/0x1b0
[  157.744774]  [<ffffffff811fe6cc>] SyS_ioctl+0x3c/0x70
[  157.744776]  [<ffffffff8180fe69>] entry_SYSCALL_64_fastpath+0x1c/0xac

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97491
Fixes: 87660502 ("drm/i915/gen6+: Interpret mailbox error flags")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Lyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Link: http://patchwork.freedesktop.org/patch/msgid/20160826105926.3413-1-chris@chris-wilson.co.ukAcked-by: NMika Kuoppala <mika.kuoppala@intel.com>

Now that we can hook into update_crtcs and control the order in which we
update CRTCs at each modeset, we can finish the final step of fixing
Skylake's watermark handling by performing DDB updates at the same time
as plane updates and watermark updates.

The first major change in this patch is skl_update_crtcs(), which
handles ensuring that we order each CRTC update in our atomic commits
properly so that they honor the DDB flush order.

The second major change in this patch is the order in which we flush the
pipes. While the previous order may have worked, it can't be used in
this approach since it no longer will do the right thing. For example,
using the old ddb flush order:

We have pipes A, B, and C enabled, and we're disabling C. Initial ddb
allocation looks like this:

|   A   |   B   |xxxxxxx|

Since we're performing the ddb updates after performing any CRTC
disablements in intel_atomic_commit_tail(), the space to the right of
pipe B is unallocated.

1. Flush pipes with new allocation contained into old space. None
   apply, so we skip this
2. Flush pipes having their allocation reduced, but overlapping with a
   previous allocation. None apply, so we also skip this
3. Flush pipes that got more space allocated. This applies to A and B,
   giving us the following update order: A, B

This is wrong, since updating pipe A first will cause it to overlap with
B and potentially burst into flames. Our new order (see the code
comments for details) would update the pipes in the proper order: B, A.

As well, we calculate the order for each DDB update during the check
phase, and reference it later in the commit phase when we hit
skl_update_crtcs().

This long overdue patch fixes the rest of the underruns on Skylake.

Changes since v1:
 - Add skl_ddb_entry_write() for cursor into skl_write_cursor_wm()
Changes since v2:
 - Use the method for updating CRTCs that Ville suggested
 - In skl_update_wm(), only copy the watermarks for the crtc that was
   passed to us
Changes since v3:
 - Small comment fix in skl_ddb_allocation_overlaps()
Changes since v4:
 - Remove the second loop in intel_update_crtcs() and use Ville's
   suggestion for updating the ddb allocations in the right order
 - Get rid of the second loop and just use the ddb state as it updates
   to determine what order to update everything in (thanks for the
   suggestion Ville)
 - Simplify skl_ddb_allocation_overlaps()
 - Split actual overlap checking into it's own helper

Fixes: 0e8fb7ba ("drm/i915/skl: Flush the WM configuration")
Fixes: 8211bd5b ("drm/i915/skl: Program the DDB allocation")
[omitting CC for stable, since this patch will need to be changed for
such backports first]

Testcase: kms_cursor_legacy
Testcase: plane-all-modeset-transition
Signed-off-by: NLyude <cpaul@redhat.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471961565-28540-2-git-send-email-cpaul@redhat.com

Thanks to Ville for suggesting this as a potential solution to pipe
underruns on Skylake.

On Skylake all of the registers for configuring planes, including the
registers for configuring their watermarks, are double buffered. New
values written to them won't take effect until said registers are
"armed", which is done by writing to the PLANE_SURF (or in the case of
cursor planes, the CURBASE register) register.

With this in mind, up until now we've been updating watermarks on skl
like this:

  non-modeset {
   - calculate (during atomic check phase)
   - finish_atomic_commit:
     - intel_pre_plane_update:
        - intel_update_watermarks()
     - {vblank happens; new watermarks + old plane values => underrun }
     - drm_atomic_helper_commit_planes_on_crtc:
        - start vblank evasion
        - write new plane registers
        - end vblank evasion
  }

  or

  modeset {
   - calculate (during atomic check phase)
   - finish_atomic_commit:
     - crtc_enable:
        - intel_update_watermarks()
     - {vblank happens; new watermarks + old plane values => underrun }
     - drm_atomic_helper_commit_planes_on_crtc:
        - start vblank evasion
        - write new plane registers
        - end vblank evasion
  }

Now we update watermarks atomically like this:

  non-modeset {
   - calculate (during atomic check phase)
   - finish_atomic_commit:
     - intel_pre_plane_update:
        - intel_update_watermarks() (wm values aren't written yet)
     - drm_atomic_helper_commit_planes_on_crtc:
        - start vblank evasion
        - write new plane registers
        - write new wm values
        - end vblank evasion
  }

  modeset {
   - calculate (during atomic check phase)
   - finish_atomic_commit:
     - crtc_enable:
        - intel_update_watermarks() (actual wm values aren't written
          yet)
     - drm_atomic_helper_commit_planes_on_crtc:
        - start vblank evasion
        - write new plane registers
	- write new wm values
        - end vblank evasion
  }

So this patch moves all of the watermark writes into the right place;
inside of the vblank evasion where we update all of the registers for
each plane. While this patch doesn't fix everything, it does allow us to
update the watermark values in the way the hardware expects us to.

Changes since original patch series:
 - Remove mutex_lock/mutex_unlock since they don't do anything and we're
   not touching global state
 - Move skl_write_cursor_wm/skl_write_plane_wm functions into
   intel_pm.c, make externally visible
 - Add skl_write_plane_wm calls to skl_update_plane
 - Fix conditional for for loop in skl_write_plane_wm (level < max_level
   should be level <= max_level)
 - Make diagram in commit more accurate to what's actually happening
 - Add Fixes:

Changes since v1:
 - Use IS_GEN9() instead of IS_SKYLAKE() since these fixes apply to more
   then just Skylake
 - Update description to make it clear this patch doesn't fix everything
 - Check if pipes were actually changed before writing watermarks

Changes since v2:
 - Write PIPE_WM_LINETIME during vblank evasion

Changes since v3:
 - Rebase against new SAGV patch changes

Changes since v4:
 - Add a parameter to choose what skl_wm_values struct to use when
   writing new plane watermarks

Changes since v5:
 - Remove cursor ddb entry write in skl_write_cursor_wm(), defer until
   patch 6
 - Write WM_LINETIME in intel_begin_crtc_commit()

Changes since v6:
 - Remove redundant dirty_pipes check in skl_write_plane_wm (we check
   this in all places where we call this function, and it was supposed
   to have been removed earlier anyway)
 - In i9xx_update_cursor(), use dev_priv->info.gen >= 9 instead of
   IS_GEN9(dev_priv). We do this everywhere else and I'd imagine this
   needs to be done for gen10 as well

Changes since v7:
 - Fix rebase fail (unused variable obj)
 - Make struct skl_wm_values *wm const
 - Fix indenting
 - Use INTEL_GEN() instead of dev_priv->info.gen

Changes since v8:
 - Don't forget calls to skl_write_plane_wm() when disabling planes
 - Use INTEL_GEN(), not INTEL_INFO()->gen in intel_begin_crtc_commit()

Fixes: 2d41c0b5 ("drm/i915/skl: SKL Watermark Computation")
Signed-off-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471884608-10671-1-git-send-email-cpaul@redhat.com
Link: http://patchwork.freedesktop.org/patch/msgid/1471884608-10671-1-git-send-email-cpaul@redhat.com

If we're enabling a pipe, we'll need to modify the watermarks on all
active planes. Since those planes won't be added to the state on
their own, we need to add them ourselves.
Signed-off-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-6-git-send-email-cpaul@redhat.com
(cherry picked from commit 05a76d3d)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

When we write watermark values to the hardware, those values are stored
in dev_priv->wm.skl_hw.  However with recent watermark changes, the
results structure we're copying from only contains valid watermark and
DDB values for the pipes that are actually changing; the values for
other pipes remain 0.  Thus a blind copy of the entire skl_wm_values
structure will clobber the values for unchanged pipes...we need to be
more selective and only copy over the values for the changing pipes.

This mistake was hidden until recently due to another bug that caused us
to erroneously re-calculate watermarks for all active pipes rather than
changing pipes.  Only when that bug was fixed was the impact of this bug
discovered (e.g., modesets failing with "Requested display configuration
exceeds system watermark limitations" messages and leaving watermarks
non-functional, even ones initiated by intel_fbdev_restore_mode).

Changes since v1:
 - Add a function for copying a pipe's wm values
   (skl_copy_wm_for_pipe()) so we can reuse this later

Fixes: 734fa01f ("drm/i915/gen9: Calculate watermarks during atomic 'check' (v2)")
Fixes: 9b613022 ("drm/i915/gen9: Re-allocate DDB only for changed pipes")
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Cc: stable@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-4-git-send-email-cpaul@redhat.com
(cherry picked from commit 2722efb9)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Since the watermark calculations for Skylake are still broken, we're apt
to hitting underruns very easily under multi-monitor configurations.
While it would be lovely if this was fixed, it's not. Another problem
that's been coming from this however, is the mysterious issue of
underruns causing full system hangs. An easy way to reproduce this with
a skylake system:

- Get a laptop with a skylake GPU, and hook up two external monitors to
  it
- Move the cursor from the built-in LCD to one of the external displays
  as quickly as you can
- You'll get a few pipe underruns, and eventually the entire system will
  just freeze.

After doing a lot of investigation and reading through the bspec, I
found the existence of the SAGV, which is responsible for adjusting the
system agent voltage and clock frequencies depending on how much power
we need. According to the bspec:

"The display engine access to system memory is blocked during the
 adjustment time. SAGV defaults to enabled. Software must use the
 GT-driver pcode mailbox to disable SAGV when the display engine is not
 able to tolerate the blocking time."

The rest of the bspec goes on to explain that software can simply leave
the SAGV enabled, and disable it when we use interlaced pipes/have more
then one pipe active.

Sure enough, with this patchset the system hangs resulting from pipe
underruns on Skylake have completely vanished on my T460s. Additionally,
the bspec mentions turning off the SAGV	with more then one pipe enabled
as a workaround for display underruns. While this patch doesn't entirely
fix that, it looks like it does improve the situation a little bit so
it's likely this is going to be required to make watermarks on Skylake
fully functional.

This will still need additional work in the future: we shouldn't be
enabling the SAGV if any of the currently enabled planes can't enable WM
levels that introduce latencies >= 30 µs.

Changes since v11:
 - Add skl_can_enable_sagv()
 - Make sure we don't enable SAGV when not all planes can enable
   watermarks >= the SAGV engine block time. I was originally going to
   save this for later, but I recently managed to run into a machine
   that was having problems with a single pipe configuration + SAGV.
 - Make comparisons to I915_SKL_SAGV_NOT_CONTROLLED explicit
 - Change I915_SAGV_DYNAMIC_FREQ to I915_SAGV_ENABLE
 - Move printks outside of mutexes
 - Don't print error messages twice
Changes since v10:
 - Apparently sandybridge_pcode_read actually writes values and reads
   them back, despite it's misleading function name. This means we've
   been doing this mostly wrong and have been writing garbage to the
   SAGV control. Because of this, we no longer attempt to read the SAGV
   status during initialization (since there are no helpers for this).
 - mlankhorst noticed that this patch was breaking on some very early
   pre-release Skylake machines, which apparently don't allow you to
   disable the SAGV. To prevent machines from failing tests due to SAGV
   errors, if the first time we try to control the SAGV results in the
   mailbox indicating an invalid command, we just disable future attempts
   to control the SAGV state by setting dev_priv->skl_sagv_status to
   I915_SKL_SAGV_NOT_CONTROLLED and make a note of it in dmesg.
 - Move mutex_unlock() a little higher in skl_enable_sagv(). This
   doesn't actually fix anything, but lets us release the lock a little
   sooner since we're finished with it.
Changes since v9:
 - Only enable/disable sagv on Skylake
Changes since v8:
 - Add intel_state->modeset guard to the conditional for
   skl_enable_sagv()
Changes since v7:
 - Remove GEN9_SAGV_LOW_FREQ, replace with GEN9_SAGV_IS_ENABLED (that's
   all we use it for anyway)
 - Use GEN9_SAGV_IS_ENABLED instead of 0x1 for clarification
 - Fix a styling error that snuck past me
Changes since v6:
 - Protect skl_enable_sagv() with intel_state->modeset conditional in
   intel_atomic_commit_tail()
Changes since v5:
 - Don't use is_power_of_2. Makes things confusing
 - Don't use the old state to figure out whether or not to
   enable/disable the sagv, use the new one
 - Split the loop in skl_disable_sagv into it's own function
 - Move skl_sagv_enable/disable() calls into intel_atomic_commit_tail()
Changes since v4:
 - Use is_power_of_2 against active_crtcs to check whether we have > 1
   pipe enabled
 - Fix skl_sagv_get_hw_state(): (temp & 0x1) indicates disabled, 0x0
   enabled
 - Call skl_sagv_enable/disable() from pre/post-plane updates
Changes since v3:
 - Use time_before() to compare timeout to jiffies
Changes since v2:
 - Really apply minor style nitpicks to patch this time
Changes since v1:
 - Added comments about this probably being one of the requirements to
   fixing Skylake's watermark issues
 - Minor style nitpicks from Matt Roper
 - Disable these functions on Broxton, since it doesn't have an SAGV
Signed-off-by: NLyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-3-git-send-email-cpaul@redhat.com
[mlankhorst: ENOSYS -> ENXIO, whitespace fixes]

(cherry picked from commit 656d1b89)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

In order to add proper support for the SAGV, we need to be able to know
what the cause of a failure to change the SAGV through the pcode mailbox
was. The reasoning for this is that some very early pre-release Skylake
machines don't actually allow you to control the SAGV on them, and
indicate an invalid mailbox command was sent.

This also might come in handy in the future for debugging.

Changes since v1:
 - Add functions for interpreting gen6 mailbox error codes along with
   gen7+ error codes, and actually interpret those codes properly
 - Renamed patch to reflect new behavior
Signed-off-by: NLyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-2-git-send-email-cpaul@redhat.com
[mlankhorst: -ENOSYS -> -ENXIO for checkpatch]

(cherry picked from commit 87660502)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

It's possible to have a non-zero plane mask and still wind up with a
total data rate of zero.  There are two cases where this can happen:

 * planes are active (from the KMS point of view), but are
   all fully clipped (positioned offscreen)
 * the only active plane on a CRTC is the cursor (which is handled
   independently and not counted into the general data rate computations

These are both valid display setups (although unusual), so we need to
drop the WARN().
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Testcase: kms_universal_planes.cursor-only-pipe-*
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466196140-16336-4-git-send-email-matthew.d.roper@intel.com
Cc: stable@vger.kernel.org #v4.7+
(cherry picked from commit 43aa7e87)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

intel_state->active_crtcs is usually only initialized when doing a
modeset.  During our first atomic commit after boot, we're effectively
faking a modeset to sanitize the DDB/wm setup, so ensure that this field
gets initialized before use.

v2:
 - Don't clobber active_crtcs if our first commit really is a modeset
   (Maarten)
 - Grab connection_mutex when faking a modeset during sanitization
   (Maarten)
Reported-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Tested-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466196140-16336-2-git-send-email-matthew.d.roper@intel.com
Cc: stable@vger.kernel.org #v4.7+
(cherry picked from commit 1b54a880)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

If we're enabling a pipe, we'll need to modify the watermarks on all
active planes. Since those planes won't be added to the state on
their own, we need to add them ourselves.
Signed-off-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-6-git-send-email-cpaul@redhat.com

When we write watermark values to the hardware, those values are stored
in dev_priv->wm.skl_hw.  However with recent watermark changes, the
results structure we're copying from only contains valid watermark and
DDB values for the pipes that are actually changing; the values for
other pipes remain 0.  Thus a blind copy of the entire skl_wm_values
structure will clobber the values for unchanged pipes...we need to be
more selective and only copy over the values for the changing pipes.

This mistake was hidden until recently due to another bug that caused us
to erroneously re-calculate watermarks for all active pipes rather than
changing pipes.  Only when that bug was fixed was the impact of this bug
discovered (e.g., modesets failing with "Requested display configuration
exceeds system watermark limitations" messages and leaving watermarks
non-functional, even ones initiated by intel_fbdev_restore_mode).

Changes since v1:
 - Add a function for copying a pipe's wm values
   (skl_copy_wm_for_pipe()) so we can reuse this later

Fixes: 734fa01f ("drm/i915/gen9: Calculate watermarks during atomic 'check' (v2)")
Fixes: 9b613022 ("drm/i915/gen9: Re-allocate DDB only for changed pipes")
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NLyude <cpaul@redhat.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Cc: stable@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-4-git-send-email-cpaul@redhat.com

Since the watermark calculations for Skylake are still broken, we're apt
to hitting underruns very easily under multi-monitor configurations.
While it would be lovely if this was fixed, it's not. Another problem
that's been coming from this however, is the mysterious issue of
underruns causing full system hangs. An easy way to reproduce this with
a skylake system:

- Get a laptop with a skylake GPU, and hook up two external monitors to
  it
- Move the cursor from the built-in LCD to one of the external displays
  as quickly as you can
- You'll get a few pipe underruns, and eventually the entire system will
  just freeze.

After doing a lot of investigation and reading through the bspec, I
found the existence of the SAGV, which is responsible for adjusting the
system agent voltage and clock frequencies depending on how much power
we need. According to the bspec:

"The display engine access to system memory is blocked during the
 adjustment time. SAGV defaults to enabled. Software must use the
 GT-driver pcode mailbox to disable SAGV when the display engine is not
 able to tolerate the blocking time."

The rest of the bspec goes on to explain that software can simply leave
the SAGV enabled, and disable it when we use interlaced pipes/have more
then one pipe active.

Sure enough, with this patchset the system hangs resulting from pipe
underruns on Skylake have completely vanished on my T460s. Additionally,
the bspec mentions turning off the SAGV	with more then one pipe enabled
as a workaround for display underruns. While this patch doesn't entirely
fix that, it looks like it does improve the situation a little bit so
it's likely this is going to be required to make watermarks on Skylake
fully functional.

This will still need additional work in the future: we shouldn't be
enabling the SAGV if any of the currently enabled planes can't enable WM
levels that introduce latencies >= 30 µs.

Changes since v11:
 - Add skl_can_enable_sagv()
 - Make sure we don't enable SAGV when not all planes can enable
   watermarks >= the SAGV engine block time. I was originally going to
   save this for later, but I recently managed to run into a machine
   that was having problems with a single pipe configuration + SAGV.
 - Make comparisons to I915_SKL_SAGV_NOT_CONTROLLED explicit
 - Change I915_SAGV_DYNAMIC_FREQ to I915_SAGV_ENABLE
 - Move printks outside of mutexes
 - Don't print error messages twice
Changes since v10:
 - Apparently sandybridge_pcode_read actually writes values and reads
   them back, despite it's misleading function name. This means we've
   been doing this mostly wrong and have been writing garbage to the
   SAGV control. Because of this, we no longer attempt to read the SAGV
   status during initialization (since there are no helpers for this).
 - mlankhorst noticed that this patch was breaking on some very early
   pre-release Skylake machines, which apparently don't allow you to
   disable the SAGV. To prevent machines from failing tests due to SAGV
   errors, if the first time we try to control the SAGV results in the
   mailbox indicating an invalid command, we just disable future attempts
   to control the SAGV state by setting dev_priv->skl_sagv_status to
   I915_SKL_SAGV_NOT_CONTROLLED and make a note of it in dmesg.
 - Move mutex_unlock() a little higher in skl_enable_sagv(). This
   doesn't actually fix anything, but lets us release the lock a little
   sooner since we're finished with it.
Changes since v9:
 - Only enable/disable sagv on Skylake
Changes since v8:
 - Add intel_state->modeset guard to the conditional for
   skl_enable_sagv()
Changes since v7:
 - Remove GEN9_SAGV_LOW_FREQ, replace with GEN9_SAGV_IS_ENABLED (that's
   all we use it for anyway)
 - Use GEN9_SAGV_IS_ENABLED instead of 0x1 for clarification
 - Fix a styling error that snuck past me
Changes since v6:
 - Protect skl_enable_sagv() with intel_state->modeset conditional in
   intel_atomic_commit_tail()
Changes since v5:
 - Don't use is_power_of_2. Makes things confusing
 - Don't use the old state to figure out whether or not to
   enable/disable the sagv, use the new one
 - Split the loop in skl_disable_sagv into it's own function
 - Move skl_sagv_enable/disable() calls into intel_atomic_commit_tail()
Changes since v4:
 - Use is_power_of_2 against active_crtcs to check whether we have > 1
   pipe enabled
 - Fix skl_sagv_get_hw_state(): (temp & 0x1) indicates disabled, 0x0
   enabled
 - Call skl_sagv_enable/disable() from pre/post-plane updates
Changes since v3:
 - Use time_before() to compare timeout to jiffies
Changes since v2:
 - Really apply minor style nitpicks to patch this time
Changes since v1:
 - Added comments about this probably being one of the requirements to
   fixing Skylake's watermark issues
 - Minor style nitpicks from Matt Roper
 - Disable these functions on Broxton, since it doesn't have an SAGV
Signed-off-by: NLyude <cpaul@redhat.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-3-git-send-email-cpaul@redhat.com
[mlankhorst: ENOSYS -> ENXIO, whitespace fixes]