gmux is a microcontroller built into dual GPU MacBook Pros.
On pre-retina MBPs, if we're the inactive GPU, we need apple-gmux
to temporarily switch DDC so that we can probe the panel's EDID.

The checks for CONFIG_VGA_ARB and CONFIG_VGA_SWITCHEROO are necessary
because if either of them is disabled but gmux is present, the driver
would never load, even if we're the active GPU. (vga_default_device()
would evaluate to NULL and vga_switcheroo_handler_flags() would
evaluate to 0.)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/552da6d85a82092146af7b0693595fa2a9ea376b.1452525860.git.lukas@wunner.de

gmux is a microcontroller built into dual GPU MacBook Pros.
On pre-retina MBPs, if we're the inactive GPU, we need apple-gmux
to temporarily switch DDC so that we can probe the panel's EDID.

The checks for CONFIG_VGA_ARB and CONFIG_VGA_SWITCHEROO are necessary
because if either of them is disabled but gmux is present, the driver
would never load, even if we're the active GPU. (vga_default_device()
would evaluate to NULL and vga_switcheroo_handler_flags() would
evaluate to 0.)

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/d9542ca5041178165d3ff286c90cc99634f7d2ce.1452525860.git.lukas@wunner.de

gmux is a microcontroller built into dual GPU MacBook Pros.
On pre-retina MBPs, if we're the inactive GPU, we need apple-gmux
to temporarily switch DDC so that we can probe the panel's EDID.

The checks for CONFIG_VGA_ARB and CONFIG_VGA_SWITCHEROO are necessary
because if either of them is disabled but gmux is present, the driver
would never load, even if we're the active GPU. (vga_default_device()
would evaluate to NULL and vga_switcheroo_handler_flags() would
evaluate to 0.)

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/f56ee6a0600a3e1bb5bed4d0db4ed9ade7445c47.1452525860.git.lukas@wunner.de

Centralize gmux' ACPI HID in a header file and add apple_gmux_present().
This can be used by other drivers to activate quirks specific to dual
GPU MacBook Pros & Mac Pros. The alternative would be to hardcode DMI
or PCI IDs and amend them whenever Apple introduces a new machine.
Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Reviewed-by: NDarren Hart <dvhart@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/89c23769058a340e5e11d4a7102f3793d3b0c94c.1452525860.git.lukas@wunner.de

The pre-retina MacBook Pro uses an LVDS panel and a gmux controller
to switch the panel between its two GPUs. The panel mode in VBIOS
is notoriously bogus on these machines.

Use drm_get_edid_switcheroo() in lieu of drm_get_edid() on LVDS
if the vga_switcheroo handler is capable of temporarily switching
the panel's DDC lines to the discrete GPU. This allows us to retrieve
the EDID if the panel is currently muxed to the integrated GPU.

This only enables EDID probing on the pre-retina MBP (2008 - 2013).
The retina MBP (2012 - present) uses eDP and gmux is not capable of
switching AUX separately from the main link on these models.
This will be addressed in later patches.

List of pre-retina MBPs with dual GPUs, one of them AMD:
    [MBP  8,2 2011  intel SNB + amd turks     pre-retina  15"]
    [MBP  8,3 2011  intel SNB + amd turks     pre-retina  17"]

v3: Commit newly added due to introduction of drm_get_edid_switcheroo()
    wrapper which drivers need to opt-in to.

v5: Rebase on "vga_switcheroo: Add handler flags infrastructure",
    i.e. call drm_get_edid_switcheroo() only if the handler
    indicates that DDC is switchable.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/dae71655e8c484fbef492d3389c157975f9622c9.1452525860.git.lukas@wunner.de

The pre-retina MacBook Pro uses an LVDS panel and a gmux controller
to switch the panel between its two GPUs. The panel mode in VBIOS
is notoriously bogus on these machines.

Use drm_get_edid_switcheroo() in lieu of drm_get_edid() on LVDS
if the vga_switcheroo handler is capable of temporarily switching
the panel's DDC lines to the discrete GPU. This allows us to retrieve
the EDID if the panel is currently muxed to the integrated GPU.
Likewise, ask vga_switcheroo to switch DDC before probing LVDS
connectors.

This only enables EDID probing on the pre-retina MBP (2008 - 2013).
The retina MBP (2012 - present) uses eDP and gmux is not capable of
switching AUX separately from the main link on these models.
This will be addressed in later patches.

List of pre-retina MBPs with dual GPUs, either or both Nvidia:
    [MBP  5,1 2008  nvidia MCP79 + G96        pre-retina  15"]
    [MBP  5,2 2009  nvidia MCP79 + G96        pre-retina  17"]
    [MBP  5,3 2009  nvidia MCP79 + G96        pre-retina  15"]
    [MBP  6,2 2010  intel ILK + nvidia GT216  pre-retina  15"]
    [MBP  6,1 2010  intel ILK + nvidia GT216  pre-retina  17"]
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]

v3: Commit newly added due to introduction of drm_get_edid_switcheroo()
    wrapper which drivers need to opt-in to.

v5: Rebase on "vga_switcheroo: Add handler flags infrastructure",
    i.e. call drm_get_edid_switcheroo() only if the handler
    indicates that DDC is switchable.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/e9466eb3d66b5b30f1e93c3b3da79d8b9ad0830f.1452525860.git.lukas@wunner.de

The pre-retina MacBook Pro uses an LVDS panel and a gmux controller
to switch the panel between its two GPUs. The panel mode in VBIOS
is notoriously bogus on these machines and some models have no
VBIOS at all.

Use drm_get_edid_switcheroo() in lieu of drm_get_edid() on LVDS
if the vga_switcheroo handler is capable of temporarily switching
the panel's DDC lines to the integrated GPU. This allows us to
retrieve the EDID if the panel is currently muxed to the discrete GPU.

This only enables EDID probing on the pre-retina MBP (2008 - 2013).
The retina MBP (2012 - present) uses eDP and gmux is not capable of
switching AUX separately from the main link on these models.
This will be addressed in later patches.

List of pre-retina MBPs with dual GPUs, one of them Intel:
    [MBP  6,2 2010  intel ILK + nvidia GT216  pre-retina  15"]
    [MBP  6,1 2010  intel ILK + nvidia GT216  pre-retina  17"]
    [MBP  8,2 2011  intel SNB + amd turks     pre-retina  15"]
    [MBP  8,3 2011  intel SNB + amd turks     pre-retina  17"]
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]

v3: Commit newly added due to introduction of drm_get_edid_switcheroo()
    wrapper which drivers need to opt-in to.

v5: Rebase on "vga_switcheroo: Add handler flags infrastructure",
    i.e. call drm_get_edid_switcheroo() only if the handler
    indicates that DDC is switchable.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/bb095e14a2259be7fdd10092f9d6874a9be8f27b.1452525860.git.lukas@wunner.de

Originally by Seth Forshee <seth.forshee@canonical.com>, 2012-10-04:
    Some dual graphics machines support muxing the DDC separately from
    the display, so make use of this functionality when reading the EDID
    on the inactive GPU. Also serialize drm_get_edid() with a mutex to
    avoid races on the DDC mux state.

Modified by Dave Airlie <airlied@gmail.com>, 2012-12-22:
    I can't figure out why I didn't like this, but I rewrote this [...]
    to lock/unlock the ddc lines [...]. I think I'd prefer something
    like that otherwise the interface got really ugly.

Modified by Lukas Wunner <lukas@wunner.de>, 2015-04 - 2015-09:
    v3:   Move vga_switcheroo calls to a wrapper around drm_get_edid()
          which drivers can call on muxed machines. This avoids other
          drivers having to go through the vga_switcheroo motions even
          though they are never used on a muxed platform
          (Thierry Reding, Daniel Vetter, Alex Deucher)

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NPierre Moreau <pierre.morrow@free.fr>
    [MBP  5,3 2009  nvidia MCP79 + G96        pre-retina  15"]
Tested-by: NWilliam Brown <william@blackhats.net.au>
    [MBP  8,2 2011  intel SNB + amd turks     pre-retina  15"]
Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/b898d0da4c134f2642d0122479006863e1830723.1452525860.git.lukas@wunner.de

Originally by Seth Forshee <seth.forshee@canonical.com>, 2012-10-04:
    The gmux allows muxing the DDC independently from the display, so
    support this functionality. This will allow reading the EDID for the
    inactive GPU, fixing issues with machines that either don't have a
    VBT or have invalid mode data in the VBT.

Modified by Lukas Wunner <lukas@wunner.de>, 2015-04 - 2015-12:
    Change semantics of ->switch_ddc handler callback to return previous
    DDC owner. Original version tried to determine previous DDC owner
    with find_active_client() in vga_switcheroo but this fails if the
    inactive client registers before the active client.

    v2.4: Retain semantics of ->switchto handler callback to switch all
          pins, including DDC (Daniel Vetter)

    v4:   Advertise ->switch_ddc handler callback only on the pre-retina
          Macbook Pro. The retina uses eDP instead of LVDS and gmux no
          longer does the muxing itself but merely controls an external
          mux. That mux is incapable of switching the AUX channel
          separately from the main link. It's an NXP CBTL06142
          (alternate parts: TI HD3SS212, Pericom PI3VDP12412,
          see datasheets below).

    v5:   Rebase on "apple-gmux: Track switch state".
          Rebase on "vga_switcheroo: Add handler flags infrastructure".
          Rebase on 5d170139 ("Constify vga_switcheroo_handler"),
          requires 2 structs, 1x with ->switchto for pre-retinas,
          1x without for retinas).
          Add error message if handler registration with vga_switcheroo
          fails.

    Teardowns identifying the mux:
    http://www.electronicproducts.com/-whatsinside_text-145.aspx
    http://slideshare.net/jjwu6266/apple-2012-wwdc-apple-macbook-pro-with-retina-display
    http://www.techrepublic.com/blog/cracking-open/teardown-shows-retina-macbook-pro-is-nearly-impossible-to-upgrade-difficult-to-work-on/

    Mux Datasheets:
    http://www.nxp.com/documents/data_sheet/CBTL06141.pdf
    http://www.ti.com/lit/ds/symlink/hd3ss212.pdf
    https://www.pericom.com/assets/Datasheets/PI3VDP12412.pdf

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Cc: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Reviewed-by: NDarren Hart <dvhart@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/17fe8bfb0415d713bb4174f84ac9aae5d7d9a5f8.1452525860.git.lukas@wunner.de

gmux has 3 switch registers:

* GMUX_PORT_SWITCH_DISPLAY switches the panel
* GMUX_PORT_SWITCH_DDC switches the panel's DDC lines
  (only on pre-retinas; on retinas this is a no-op)
* GMUX_PORT_SWITCH_EXTERNAL switches the external DP port(s)
  (only on models without Thunderbolt, i.e. introduced before 2011;
  those with Thunderbolt switch only HPD/AUX, not the main link)

Currently we switch all 3 registers in unison.

gmux does not preserve the switch state during suspend, so we currently
read GMUX_PORT_SWITCH_DISPLAY before suspend and restore all 3 registers
to this value on resume.

With the upcoming ->switch_ddc callback, GMUX_PORT_SWITCH_DDC may
temporarily contain a different value than the other 2 registers.
If we happen to suspend at this moment, we'll write an incorrect
value to GMUX_PORT_SWITCH_DDC on resume.

Also, on models with Thunderbolt the integrated GPU is unable to drive
the external DP port(s), so we want to keep GMUX_PORT_SWITCH_EXTERNAL
permanently switched to the discrete GPU on those machines.

Consequently we can no longer assume that GMUX_PORT_SWITCH_DISPLAY
represents the correct value for all 3 registers on suspend.

Track the state of all 3 registers: Add gmux_read_switch_state() and
gmux_write_switch_state(). Instead of reading the switch state on
every suspend, read it once on driver initialization so that we know
the current switch state all the time. (This allows us to use some
optimizations and shortcuts, e.g. we can skip switching DDC if we
know that it's already switched to the requested GPU.) Change the
->switchto callback to use gmux_write_switch_state().
Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Reviewed-by: NDarren Hart <dvhart@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/5679f414cb0ddf1654dcc359571f3764b275edf0.1452525860.git.lukas@wunner.de

Originally by Seth Forshee <seth.forshee@canonical.com>, 2012-10-04:
    During graphics driver initialization it's useful to be able to mux
    only the DDC to the inactive client in order to read the EDID. Add
    a switch_ddc callback to allow capable handlers to provide this
    functionality, and add vga_switcheroo_switch_ddc() to allow DRM
    to mux only the DDC.

Modified by Dave Airlie <airlied@gmail.com>, 2012-12-22:
    I can't figure out why I didn't like this, but I rewrote this [...]
    to lock/unlock the ddc lines [...]. I think I'd prefer something
    like that otherwise the interface got really ugly.

Modified by Lukas Wunner <lukas@wunner.de>, 2015-04 - 2015-10:
    Change semantics of ->switch_ddc handler callback to return previous
    DDC owner. Original version tried to determine previous DDC owner
    with find_active_client() but this fails if the inactive client
    registers before the active client.

    Don't lock vgasr_mutex in _lock_ddc() / _unlock_ddc(), it can cause
    deadlocks because (a) during switch (with vgasr_mutex already held),
    GPU is woken and probes its outputs, tries to re-acquire vgasr_mutex
    to lock DDC lines; (b) Likewise during switch, GPU is suspended and
    calls cancel_delayed_work_sync() to stop output polling, if poll
    task is running at this moment we may wait forever for it to finish.

    Instead, lock mux_hw_lock when unregistering the handler because
    the only reason why we'd want to lock vgasr_mutex in _lock_ddc() /
    _unlock_ddc() is to block the handler from disappearing while DDC
    lines are switched.

    Also acquire mux_hw_lock in stage2 to avoid race condition where
    reading the EDID and switching happens simultaneously. Likewise on
    MIGD / MDIS commands and on runtime suspend.

    v2.1: Overhaul locking, squash commits (Daniel Vetter)

    v2.2: Readability improvements (Thierry Reding)

    v2.3: Overhaul locking once more

    v2.4: Retain semantics of ->switchto handler callback to switch all
          pins, including DDC (Daniel Vetter)

    v5:   Rename ddc_lock to mux_hw_lock: Since we acquire this both
          when calling ->switch_ddc and ->switchto, it protects not just
          access to the DDC lines but to the mux in general. This is in
          line with the DRM convention to use low-level locks to avoid
          concurrent hw access (e.g. i2c, dp_aux) which are often called
          hw_lock (Daniel Vetter)

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/e81ae9722b84c5ed591805fee3ea6dbf5dc6c4b3.1452525860.git.lukas@wunner.de

Allow handlers to declare their capabilities and allow clients to
obtain that information. So far we have these use cases:

* If the handler is able to switch DDC separately, clients need to
  probe EDID with drm_get_edid_switcheroo(). We should allow them
  to detect a capable handler to ensure this function only gets
  called when needed.

* Likewise if the handler is unable to switch AUX separately, the active
  client needs to communicate link training parameters to the inactive
  client, which may then skip the AUX handshake and set up its output
  with these pre-calibrated values (DisplayPort specification v1.1a,
  section 2.5.3.3). Clients need a way to recognize such a situation.

The flags for the radeon_atpx_handler and amdgpu_atpx_handler are
initially set to 0, this can later on be amended with
  handler_flags |= VGA_SWITCHEROO_CAN_SWITCH_DDC;
when a ->switch_ddc callback is added.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115Tested-by: NLukas Wunner <lukas@wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina  15"]
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Reviewed-by: NDarren Hart <dvhart@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/2b0d93ed6e511ca09e95e45e0b35627f330fabce.1452525860.git.lukas@wunner.de

This allows iteration over encoders without requiring connection_mutex.

Changes since v1:
- Add a set_best_encoder helper function and update encoder_mask inside
  it.
Changes since v2:
- Relax the WARN_ON(!crtc), with explanation.
- Call set_best_encoder when connector is moved between crtc's.
- Add some paranoia to steal_encoder to prevent accidentally setting
  best_encoder to NULL.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/56AA200A.6070501@linux.intel.com

While we steal the encoder away from the connector the connector may
be updated to use a different encoder.

Without this change if 2 connectors swap encoders one of them will
end up without a crtc.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452160762-30487-5-git-send-email-maarten.lankhorst@linux.intel.com

This should only be touched by drm_atomic_helper.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452160762-30487-4-git-send-email-maarten.lankhorst@linux.intel.com

This is similar to the other drm_for_each_*_mask functions.

Changes since v1:
- Use for_each_if
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452160762-30487-3-git-send-email-maarten.lankhorst@linux.intel.com

This is useful for adding encoder_mask in crtc_state.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452160762-30487-2-git-send-email-maarten.lankhorst@linux.intel.com

Userspace is the one in charge of flush CPU by wrapping mmap with
begin{,end}_cpu_access.

v2: Remove LLC check cause we have dma-buf sync providers now. Also, fix return
before transferring ownership when mmap fails.
v3: Fix return values.
v4: !obj->base.filp is user triggerable, so removed the WARN_ON.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NTiago Vignatti <tiago.vignatti@intel.com>
Reviewed-by: NStéphane Marchesin <marcheu@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1450820214-12509-6-git-send-email-tiago.vignatti@intel.com

This function is meant to be used with dma-buf mmap, when finishing the CPU
access of the mapped pointer.

The error case should be rare to happen though, requiring the buffer become
active during the sync period and for the end_cpu_access to be interrupted. So
we use a uninterruptible mutex_lock to spit out when it ever happens.

v2: disable interruption to make sure errors are reported.
v3: update to the new end_cpu_access API.
v7: use .write = false cause it doesn't need to know whether it's write.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NTiago Vignatti <tiago.vignatti@intel.com>
Reviewed-by: NStéphane Marchesin <marcheu@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1450820214-12509-5-git-send-email-tiago.vignatti@intel.com

This patch removes range-based information used for optimizations in
begin_cpu_access and end_cpu_access.

We don't have any user nor implementation using range-based flush. It seems a
consensus that if we ever want something like that again (or even more robust
using 2D, 3D sub-range regions) we can use the upcoming dma-buf sync ioctl for
such.

Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NTiago Vignatti <tiago.vignatti@intel.com>
Reviewed-by: NStéphane Marchesin <marcheu@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1450820214-12509-3-git-send-email-tiago.vignatti@intel.com

Currently DRM_IOCTL_PRIME_HANDLE_TO_FD rejects all flags except
(DRM|O)_CLOEXEC making it difficult (maybe impossible) for userspace
to mmap() the resulting dma-buf even when this is supported by the
DRM driver.

It is trivial to relax the restriction and permit read/write access.
This is safe because the flags are seldom touched by drm; mostly they
are passed verbatim to dma_buf calls.

v3 (Tiago): removed unused flags variable from drm_prime_handle_to_fd_ioctl.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NTiago Vignatti <tiago.vignatti@intel.com>
Reviewed-by: NStéphane Marchesin <marcheu@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1450820214-12509-2-git-send-email-tiago.vignatti@intel.com

Fixes: 0417d424 (drm/tegra: Stop cancelling page flip events)
Signed-off-by: NDave Airlie <airlied@redhat.com>

First drm-misc pull req for 4.6. Big one is the drm_event cleanup, which
is also prep work for adding android fence support to kms (Gustavo is
planning to do that). Otherwise random small bits all over.

* tag 'topic/drm-misc-2016-02-08' of git://anongit.freedesktop.org/drm-intel: (33 commits)
  gma500: clean up an excessive and confusing helper
  drm/gma500: remove helper function
  drm/vmwgfx: Nuke preclose hook
  drm/vc4: Nuke preclose hook
  drm/tilcdc: Nuke preclose hook
  drm/tegra: Stop cancelling page flip events
  drm/shmob: Nuke preclose hook
  drm/rcar: Nuke preclose hook
  drm/omap: Nuke close hooks
  drm/msm: Nuke preclose hooks
  drm/imx: Unconfuse preclose logic
  drm/exynos: Remove event cancelling from postclose
  drm/atmel: Nuke preclose
  drm/i915: Nuke intel_modeset_preclose
  drm: Nuke vblank event file cleanup code
  drm: Clean up pending events in the core
  drm/vblank: Use drm_event_reserve_init
  drm/vmwgfx: fix a NULL dereference
  drm/crtc-helper: Add caveat to disable_unused_functions doc
  drm/gma500: Remove empty preclose hook
  ...

- support for v3 vbt dsi blocks (Jani)
- improve mmio debug checks (Mika Kuoppala)
- reorg the ddi port translation table entries and related code (Ville)
- reorg gen8 interrupt handling for future platforms (Tvrtko)
- refactor tile width/height computations for framebuffers (Ville)
- kerneldoc integration for intel_pm.c (Jani)
- move default context from engines to device-global dev_priv (Dave Gordon)
- make seqno/irq ordering coherent with execlist (Chris)
- decouple internal engine number from UABI (Chris&Tvrtko)
- tons of small fixes all over, as usual

* tag 'drm-intel-next-2016-01-24' of git://anongit.freedesktop.org/drm-intel: (148 commits)
  drm/i915: Update DRIVER_DATE to 20160124
  drm/i915: Seal busy-ioctl uABI and prevent leaking of internal ids
  drm/i915: Decouple execbuf uAPI from internal implementation
  drm/i915: Use ordered seqno write interrupt generation on gen8+ execlists
  drm/i915: Limit the auto arming of mmio debugs on vlv/chv
  drm/i915: Tune down "GT register while GT waking disabled" message
  drm/i915: tidy up a few leftovers
  drm/i915: abolish separate per-ring default_context pointers
  drm/i915: simplify allocation of driver-internal requests
  drm/i915: Fix NULL plane->fb oops on SKL
  drm/i915: Do not put big intel_crtc_state on the stack
  Revert "drm/i915: Add two-stage ILK-style watermark programming (v10)"
  drm/i915: add DOC: headline to RC6 kernel-doc
  drm/i915: turn some bogus kernel-doc comments to normal comments
  drm/i915/sdvo: revert bogus kernel-doc comments to normal comments
  drm/i915/gen9: Correct max save/restore register count during gpu reset with GuC
  drm/i915: Demote user facing DMC firmware load failure message
  drm/i915: use hlist_for_each_entry
  drm/i915: skl_update_scaler() wants a rotation bitmask instead of bit number
  drm/i915: Don't reject primary plane windowing with color keying enabled on SKL+
  ...

This is a left over from the great clean ups in the past. It's confusing as
it returns an int, yet has one caller that never uses it. The caller already
has all the right private variables local so the entire function can be
replaced by a simple if call.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160129193731.8475.47809.stgit@localhost.localdomainAcked-by: NPatrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We were getting build warning about:
drivers/gpu/drm/gma500/mdfld_dsi_output.c:407:2: warning: initialization
	from incompatible pointer type

The callback to dpms was pointing to a helper function which had a
return type of void, whereas the callback should point to a function
which has a return type of int.
On closer look it turned out that we do not need the helper function
since if we call drm_helper_connector_dpms() directly, the first check
that drm_helper_connector_dpms() does is: if (mode == connector->dpms)
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1454393155-13142-1-git-send-email-sudipm.mukherjee@gmail.comAcked-by: NPatrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Again since the drm core takes care of event unlinking/disarming this
is now just needless code.

v2: I've completely missed eaction->fpriv_head and all the related
code. We need to nuke that too to avoid accidentally deferencing the
freed-up vmwgfx-private fpriv.

v3: Also remove vmw_fpriv->fence_events and unused variables I missed.

Cc: Thomas Hellström <thellstrom@vmware.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NThomas Hellstrom <thellstrom@vmware.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452548477-15905-23-git-send-email-daniel.vetter@ffwll.chSigned-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Again since the drm core takes care of event unlinking/disarming this
is now just needless code.

v2: Fixup misplaced hunk.

Cc: Eric Anholt <eric@anholt.net>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Acked-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-14-git-send-email-daniel.vetter@ffwll.ch

Again since the drm core takes care of event unlinking/disarming this
is now just needless code.

v2: Fixup misplaced hunks.

Cc: Rob Clark <robdclark@gmail.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-13-git-send-email-daniel.vetter@ffwll.ch

The core takes care of that now.

v2: Fixup misplaced hunk.

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Terje Bergström <tbergstrom@nvidia.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Acked-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-12-git-send-email-daniel.vetter@ffwll.ch

Again since the drm core takes care of event unlinking/disarming this
is now just needless code.

v2: Fixup misplaced hunk.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-11-git-send-email-daniel.vetter@ffwll.ch

Again since the drm core takes care of event unlinking/disarming this
is now just needless code.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-10-git-send-email-daniel.vetter@ffwll.ch

Again since the core takes care of this we can remove them. While at
it also remove the postclose hook, it's empty.

v2: Laurent pointed me at even more code to delete.

v3: Remove unused flags (Tomi).

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NTomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-9-git-send-email-daniel.vetter@ffwll.ch

They only complete the page flip events to avoid oops when the drm
file closes. The core takes care of that now and we can remove this
code.

Cc: Rob Clark <robdclark@gmail.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-8-git-send-email-daniel.vetter@ffwll.ch

So this one is special, since it tries to prevent races when userspace
crashes simply by disabling the vblank machinery. Well except that imx
always has vblanks enabled, and the disable_vblank hook actually just
tries to cancel a pending pageflip. Without any locking whatsoever. Of
course this is wrong, since it'll result in the hw not actually
displaying what drm thinks is the current frontbuffer.

Well since the core takes care of the disappearing DRM fd now. So we
can nuke all this confused code without ill side-effects.

Someone else needs to audit the locking for ->newfb and
->page_flip_event and fix it up. Common approach is to reuse
dev->event_lock for this.

Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Acked-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-7-git-send-email-daniel.vetter@ffwll.ch

The core takes care of this now. And since kfree(NULL) is ok we can
simplify the function even further now.

Note: There's another spin on this patch, but for different reasons,
in-flight already: http://www.spinics.net/lists/dri-devel/msg97922.html

Cc: Inki Dae <inki.dae@samsung.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Acked-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-6-git-send-email-daniel.vetter@ffwll.ch

The only thing this did was cancle pending flip events, and the core
takes care of that now.

Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-5-git-send-email-daniel.vetter@ffwll.ch

Now that the drm core unlinks/disarms events there's no need to do so
ourselves anymore. Nuke the code.
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-4-git-send-email-daniel.vetter@ffwll.ch

The core code now takes care of unlinking drm_events from the file in
a generic way, so this code isn't needed any more.

For those wondering where the drm_vblank_put went to: With the new
logic events only get unlinked, but still exist. Hence any resources
(like vblank counters) don't need to be released since the event user
will still process the event normally. In this case this is the
callsites of send_vblank_event, which of course already have a
drm_vblank_put.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-3-git-send-email-daniel.vetter@ffwll.ch

There's really no reason to not do so, instead of replicating this
for every use-case and every driver. Now we can't just nuke the events,
since that would still mean that all drm_event users would need to know
when that has happened, since calling e.g. drm_send_event isn't allowed
any more. Instead just unlink them from the file, and detect this case
and handle it appropriately in all functions.

v2: Adjust existing kerneldoc too.

v3: Improve wording of the kerneldoc and split out vblank cleanup (Laurent).

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-2-git-send-email-daniel.vetter@ffwll.ch