This fixes an issue that was noticed on an optimus/prime laptop with
a kernel that was old enough to not support the integrated intel gfx
(which was driving all the outputs), but did have support for the
discrete radeon gpu.  The end result was not falling back to VESA and
leaving the user with a black screen.

(Plus it is kind of silly to create an framebuffer device if there
are no outputs hooked up to the gpu.)
Signed-off-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many
vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core
more fragile to drivers which don't update hw vblank counters and
vblank timestamps in sync with firing of the vblank irq and
essentially at leading edge of vblank.

This exposed a problem with radeon-kms/amdgpu-kms which do not
satisfy above requirements:

The vblank irq fires a few scanlines before start of vblank, but
programmed pageflips complete at start of vblank and
vblank timestamps update at start of vblank, whereas the
hw vblank counter increments only later, at start of vsync.

This leads to problems like off by one errors for vblank counter
updates, vblank counters apparently going backwards or vblank
timestamps apparently having time going backwards. The net result
is stuttering of graphics in games, or little hangs, as well as
total failure of timing sensitive applications.

See bug #93147 for an example of the regression on Linux 4.4-rc:

https://bugs.freedesktop.org/show_bug.cgi?id=93147

This patch tries to align all above events better from the
viewpoint of the drm core / of external callers to fix the problem:

1. The apparent start of vblank is shifted a few scanlines earlier,
so the vblank irq now always happens after start of this extended
vblank interval and thereby drm_update_vblank_count() always samples
the updated vblank count and timestamp of the new vblank interval.

To achieve this, the reporting of scanout positions by
radeon_get_crtc_scanoutpos() now operates as if the vblank starts
radeon_crtc->lb_vblank_lead_lines before the real start of the hw
vblank interval. This means that the vblank timestamps which are based
on these scanout positions will now update at this earlier start of
vblank.

2. The driver->get_vblank_counter() function will bump the returned
vblank count as read from the hw by +1 if the query happens after
the shifted earlier start of the vblank, but before the real hw increment
at start of vsync, so the counter appears to increment at start of vblank
in sync with the timestamp update.

3. Calls from vblank irq-context and regular non-irq calls are now
treated identical, always simulating the shifted vblank start, to
avoid inconsistent results for queries happening from vblank irq vs.
happening from drm_vblank_enable() or vblank_disable_fn().

4. The radeon_flip_work_func will delay mmio programming a pageflip until
the start of the real vblank iff it happens to execute inside the shifted
earlier start of the vblank, so pageflips now also appear to execute at
start of the shifted vblank, in sync with vblank counter and timestamp
updates. This to avoid some races between updates of vblank count and
timestamps that are used for swap scheduling and pageflip execution which
could cause pageflips to execute before the scheduled target vblank.

The lb_vblank_lead_lines "fudge" value is calculated as the size of
the display controllers line buffer in scanlines for the given video
mode: Vblank irq's are triggered by the line buffer logic when the line
buffer refill for a video frame ends, ie. when the line buffer source read
position enters the hw vblank. This means that a vblank irq could fire at
most as many scanlines before the current reported scanout position of the
crtc timing generator as the number of scanlines the line buffer can
maximally hold for a given video mode.

This patch has been successfully tested on a RV730 card with DCE-3 display
engine and on a evergreen card with DCE-4 display engine, in single-display
and dual-display configuration, with different video modes.

A similar patch is needed for amdgpu-kms to fix the same problem.

Limitations:

- Line buffer sizes in pixels are hard-coded on < DCE-4 to a value
  i just guessed to be high enough to work ok, lacking info on the true
  sizes atm.

Fixes: fdo#93147
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>

(v1) Tested-by: Dave Witbrodt <dawitbro@sbcglobal.net>

(v2) Refine radeon_flip_work_func() for better efficiency:

     In radeon_flip_work_func, replace the busy waiting udelay(5)
     with event lock held by a more performance and energy efficient
     usleep_range() until at least predicted true start of hw vblank,
     with some slack for scheduler happiness. Release the event lock
     during waits to not delay other outputs in doing their stuff, as
     the waiting can last up to 200 usecs in some cases.

     Retested on DCE-3 and DCE-4 to verify it still works nicely.

(v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many
vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core
more fragile to drivers which don't update hw vblank counters and
vblank timestamps in sync with firing of the vblank irq and
essentially at leading edge of vblank.

This exposed a problem with radeon-kms/amdgpu-kms which do not
satisfy above requirements:

The vblank irq fires a few scanlines before start of vblank, but
programmed pageflips complete at start of vblank and
vblank timestamps update at start of vblank, whereas the
hw vblank counter increments only later, at start of vsync.

This leads to problems like off by one errors for vblank counter
updates, vblank counters apparently going backwards or vblank
timestamps apparently having time going backwards. The net result
is stuttering of graphics in games, or little hangs, as well as
total failure of timing sensitive applications.

See bug #93147 for an example of the regression on Linux 4.4-rc:

https://bugs.freedesktop.org/show_bug.cgi?id=93147

This patch tries to align all above events better from the
viewpoint of the drm core / of external callers to fix the problem:

1. The apparent start of vblank is shifted a few scanlines earlier,
so the vblank irq now always happens after start of this extended
vblank interval and thereby drm_update_vblank_count() always samples
the updated vblank count and timestamp of the new vblank interval.

To achieve this, the reporting of scanout positions by
radeon_get_crtc_scanoutpos() now operates as if the vblank starts
radeon_crtc->lb_vblank_lead_lines before the real start of the hw
vblank interval. This means that the vblank timestamps which are based
on these scanout positions will now update at this earlier start of
vblank.

2. The driver->get_vblank_counter() function will bump the returned
vblank count as read from the hw by +1 if the query happens after
the shifted earlier start of the vblank, but before the real hw increment
at start of vsync, so the counter appears to increment at start of vblank
in sync with the timestamp update.

3. Calls from vblank irq-context and regular non-irq calls are now
treated identical, always simulating the shifted vblank start, to
avoid inconsistent results for queries happening from vblank irq vs.
happening from drm_vblank_enable() or vblank_disable_fn().

4. The radeon_flip_work_func will delay mmio programming a pageflip until
the start of the real vblank iff it happens to execute inside the shifted
earlier start of the vblank, so pageflips now also appear to execute at
start of the shifted vblank, in sync with vblank counter and timestamp
updates. This to avoid some races between updates of vblank count and
timestamps that are used for swap scheduling and pageflip execution which
could cause pageflips to execute before the scheduled target vblank.

The lb_vblank_lead_lines "fudge" value is calculated as the size of
the display controllers line buffer in scanlines for the given video
mode: Vblank irq's are triggered by the line buffer logic when the line
buffer refill for a video frame ends, ie. when the line buffer source read
position enters the hw vblank. This means that a vblank irq could fire at
most as many scanlines before the current reported scanout position of the
crtc timing generator as the number of scanlines the line buffer can
maximally hold for a given video mode.

This patch has been successfully tested on a RV730 card with DCE-3 display
engine and on a evergreen card with DCE-4 display engine, in single-display
and dual-display configuration, with different video modes.

A similar patch is needed for amdgpu-kms to fix the same problem.

Limitations:

- Line buffer sizes in pixels are hard-coded on < DCE-4 to a value
  i just guessed to be high enough to work ok, lacking info on the true
  sizes atm.

Fixes: fdo#93147
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>

(v1) Tested-by: Dave Witbrodt <dawitbro@sbcglobal.net>

(v2) Refine radeon_flip_work_func() for better efficiency:

     In radeon_flip_work_func, replace the busy waiting udelay(5)
     with event lock held by a more performance and energy efficient
     usleep_range() until at least predicted true start of hw vblank,
     with some slack for scheduler happiness. Release the event lock
     during waits to not delay other outputs in doing their stuff, as
     the waiting can last up to 200 usecs in some cases.

     Retested on DCE-3 and DCE-4 to verify it still works nicely.

(v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Drivers shouldn't clobber the passed in addfb ioctl parameters.
i915 was doing just that. To prevent it from happening again,
pass the struct around as const, starting all the way from
internal_framebuffer_create().
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This continues the pattern started in commit cc1ef118 ("drm/irq:
Make pipe unsigned and name consistent"). This is applied to the public
APIs and driver callbacks, so pretty much all drivers need to be updated
to match the new prototypes.

Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Jianwei Wang <jianwei.wang.chn@gmail.com>
Cc: Alison Wang <alison.wang@freescale.com>
Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mark Yao <mark.yao@rock-chips.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

They were added relatively early in the driver init process
which meant that in some cases the driver was not finished
initializing before external tools tried to use them which
could result in a crash depending on the timing.
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

linedur_ns, and especially pixeldur_ns are becoming rather inaccurate
to be used for the vblank timestamp correction. With 4k@60 the pixel
duration is already below 2ns, so the amount of error due to the
truncation to nanoseconds is introducing quite a bit of error.

We can avoid such problems if we instead calculate the timestamp
delta_ns directly from the dislay timings, avoiding the use of
these intermediate truncated values.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
[danvet: Squash in fixup from Thierry Reding for amdgpu.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Implement the property for DCE5+ asics.  Older asics
require a slightly more complex process.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=83226Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This adds the drm property for output csc (e.g.,
transform of output display colorspace).  Currently
only common ones (TV RGB, BT.601, BT.709) are supported,
but bypass and tv rgb are really the only useful ones at
the moment.  Additionally we could expose a user adjustable
matrix in the future.

This commit just adds the property.  The hw support will
be added in subsequent patches.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=83226Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This is a workaround for RS880 and older chips which seem to have
an additional limit on the minimum PLL input frequency.

v2: fix signed/unsigned warning

bugs:
https://bugzilla.kernel.org/show_bug.cgi?id=91861
https://bugzilla.kernel.org/show_bug.cgi?id=83461Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

The cursor_set2 hook provides the cursor hotspot position within the
cursor image. When the hotspot position changes, we can adjust the cursor
position such that the hotspot doesn't move on the screen. This prevents
the cursor from appearing to intermittently jump around on the screen
when the position of the hotspot within the cursor image changes.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Just a bit of OCD cleanup on headers - this function isn't the core
interface any more but just a helper for drivers who haven't yet
transitioned to universal planes. Put the declaration at the right
spot and sprinkle necessary #includes over all drivers.

Maybe this helps to encourage driver maintainers to do the switch.

v2: Fix #include ordering for tegra, reported by 0-day builder.

v3: Include required headers, reported by Thierry.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: NSean Paul <seanpaul@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

I've read INVBL as "invalid backlight" and got mightly confused.
The #defines are already fairly long and we can afford to extend
them a bit more without resulting in ugly code all over.

I'm not sure how useful the complicated bitmask return value of these
functions really are since no one checks them. But for now let's keep
things as is.

Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>

No users are left, kill it off! :D
Conversion to the reservation api is next on the list, after
that the functionality can be restored with rcu.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>

This is needed for the next commit, because the lockup detection
will need the read lock to run.

v4 (chk): split out forced fence completion, remove unrelated changes,
          add and handle in_reset flag
v5 (agd5f): rebase fix
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Skip the "manual" pageflip completion checks via polling and
guessing in the vblank handler radeon_crtc_handle_vblank() on
asics which are known to reliably support hw pageflip completion
irqs. Those pflip irqs are a more reliable and race-free method
of handling pageflip completion detection, whereas the "classic"
polling method has some small races in combination with dpm on,
and with the reworked pageflip implementation since Linux 3.16.

On old asics without pflip irqs, the classic method is used.

On asics with known good pflip irqs, only pflip irqs are used
by default, but a new module parameter "use_pflipirqs" allows to
override this in case we encounter asics in the wild with
unreliable or faulty pflip irqs. A module parameter of 0 allows
to use the classic method only in such a case. A parameter of 1
allows to use both classic method and pflip irqs as additional
band-aid to avoid some small races which could happen with the
classic method alone. The setting 1 gives Linux 3.16 behaviour.

Hw pflip irqs are available since R600.

Tested on DCE-4, AMD Cedar - FirePro 2270.

v2:  agd5f: only enable pflip interrupts on DCE4+ as they are not
reliable on older asics.
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

We keep a cached version of the edid in radeon_connector which
we use for determining connectedness and when to enable certain
features like hdmi audio, etc.  When the user uses the firmware
interface to override the driver with some other edid the driver's
copy is never updated.  The fetch function will check if there
is a user supplied edid and update the driver's copy if there
is.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=80691Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Split radeon_ddc_get_modes() and move it into
radeon_connectors.c since that is the only place
that uses it.
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Need to protect mmio flip programming by event lock as well.

Need to also first enable pflip irq, then mmio program,
otherwise a flip completion may get unnoticed in the vblank
of actual completion if the flip is programmed, but
radeon_flip_work_func gets preempted immediately after
mmio programming and before vblank. In that case the
vblank irq handler wouldn't run radeon_crtc_handle_vblank()
with the completion check routine, miss the completed flip,
and only notice one vblank after actual completion, causing
a false/delayed report of flip completion.
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Not needed anymore, as it is already unreffed within
radeon_flip_work_func() after its only use.
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Otherwise the DRM core and userspace will be confused about which BO the
CRTC is scanning out.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

As well as enabling the vblank interrupt. These shouldn't take any
significant amount of time, but at least pinning the BO has actually been
seen to fail in practice before, in which case we need to let userspace
know about it.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

In some cases we fetch the edid in the detect() callback
in order to determine what sort of monitor is connected.
If that happens, don't fetch the edid again in the get_modes()
callback or we will leak the edid.
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

This prevents a panic: radeon_crtc_handle_page_flip() could run before
radeon_flip_work_func(), triggering the BUG_ON() in drm_vblank_put().
Tested-by: NDieter Nützel <Dieter@nuetzel-hh.de>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Fixes a regression in 3.16-rc1 compared to 3.15.

The unbalanced calls would presumably result in the page flip interrupts
never getting disabled once they are enabled.
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

This reverts commit 75f36d86.

drm_vblank_get() is necessary to ensure the DRM vblank counter value is
up to date in drm_send_vblank_event().

Seems to fix weston hangs waiting for page flips to complete.
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

The hardware lut's only have 256 slots for indexing by a
8 bpc framebuffer. In 10 bpc scanout modes, framebuffer
color values would get truncated to their 8 msb's,
thereby losing the extra precision afforded by a 10 bpc
framebuffer.

To retain full precision, bypass the hw lut in 10 bpc
scanout mode.
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Fixes WARN()s from the DRM core since the page flip rework.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=77521Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Generated using semantic patch:

@@
expression E;
@@

- drm_get_connector_name(E)
+ E->name

[airlied: regenerated]
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Acked-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Instead of trying to flip inside the vblank period when
the buffer is idle, offload blocking for idle to a kernel
thread and program the flip directly into the hardware.

v2: add error handling, fix EBUSY handling
v3: add proper exclusive_lock handling
v4: update crtc->primary->fb when the flip actually happens
Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This reverts commit 1aab5514.

Apply the fixed up version instead.

Instead of trying to flip inside the vblank period when
the buffer is idle, offload blocking for idle to a kernel
thread and program the flip directly into the hardware.

v2: add error handling, fix EBUSY handling
v3: add proper exclusive_lock handling
Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

We activate the VBLANK irq manually anyway, so this is unnecessary.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

They are doing the same on all generations anyway.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Let's be conservative and use 100 here until we find something better.

Bugs: https://bugzilla.kernel.org/show_bug.cgi?id=75241Signed-off-by: NChristian König <christian.koenig@amd.com>