This patch introduces the GVT-g display virtualization.
It consists a collection of display MMIO handlers, like power well register
handler, pipe register handler, plane register handler, which will emulate
all display MMIOs behavior to support virtual mode setting sequence for
guest.
Signed-off-by: Bing Niu <bing.niu@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the generic vGPU MMIO emulation intercept
framework. The MPT modules will request GVT-g core logic to
emulate MMIO read/write through IO emulation operations
callback when hypervisor trapped a guest GTTMMIO read/write.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces vGPU PCI configuration space virtualization.
- Adjust the trapped GPFN(Guest Page Frame Number) window of virtual GEN
PCI BAR 0 when guest initializes PCI BAR 0 address.
- Emulate OpRegion when guest touches OpRegion.
- Pass-through a part of aperture to guest when guest initializes
aperture BAR.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The vGPU graphics memory emulation framework is responsible for graphics
memory table virtualization. Under virtualization environment, a VM will
populate the page table entry with guest page frame number(GPFN/GFN), while
HW needs a page table filled with MFN(Machine frame number). The
relationship between GFN and MFN(Machine frame number) is managed by
hypervisor, while GEN HW doesn't have such knowledge to translate a GFN.
To solve this gap, shadow GGTT/PPGTT page table is introdcued.
For GGTT, the GFN inside the guest GGTT page table entry will be translated
into MFN and written into physical GTT MMIO registers when guest write
virtual GTT MMIO registers.
For PPGTT, a shadow PPGTT page table will be created and write-protected
translated from guest PPGTT page table. And the shadow page table root
pointers will be written into the shadow context after a guest workload
is shadowed.
vGPU graphics memory emulation framework consists:
- Per-GEN HW platform page table entry bits extract/de-extract routines.
- GTT MMIO register emulation handlers, which will call hypercall to do
GFN->MFN translation when guest write GTT MMIO register
- PPGTT shadow page table routines, e.g. shadow create/destroy/out-of-sync
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces vGPU interrupt emulation framework.
The vGPU intrerrupt emulation framework is an event-based interrupt
emulation framework. It's responsible for emulating GEN hardware interrupts
during emulating other HW behaviour.
It consists several components:
- Descriptions of interrupt register bit
- Upper level <-> lower level interrupt mapping
- GEN HW IER/IMR/IIR register emulation routines
- Event-based interrupt propagation interface
When a GVT-g component wants to inject an interrupt to a VM during a
emulation, first it should specify the event needs to be emulated and the
framework will deal with the rest of emulation:
- Generating related virtual IIR bit according to virtual IER and IMRs,
- Generate related virtual upper level virtual IIR bit accodring to the
per-platform interrupt mapping
- Injecting a MSI to VM
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
A vGPU represents a virtual Intel GEN hardware, which consists following
virtual resources:
- Configuration space (virtualized)
- HW registers (virtualized)
- GGTT memory space (partitioned)
- GPU page table (shadowed)
- Fence registers (partitioned)
* virtualized: fully emulated by GVT-g.
* partitioned: Only a part of the HW resource is allowed to be accessed
by VM.
* shadowed: Resource needs to be translated and shadowed before getting
applied into HW.
This patch introduces vGPU life cycle management framework, which is
responsible for creating/destroying a vGPU and preparing/free resources
related to a vGPU.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Each vGPU expects a golden virtual HW state, which is just the state after
system is freshly powered on. GVT-g will try to load the golden virtual HW
state via kernel firmware interface.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a framework for tracking HW registers on different
GEN platforms.
Accesses to GEN HW registers from VMs will be trapped by hypervisor. It
will forward these emulation requests to GVT-g device model, which
requires this framework to search for related register descriptions.
Each MMIO entry in this framework describes a GEN HW registers, e.g.
offset, length, whether it contains RO bits, whether it can be accessed by
LRIs...and also emulation handlers for emulating register reading and
writing.
- Use i915 MMIO register definition & statement.(Joonas)
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the GVT-g vGPU HW resource management. Under
GVT-g virtualizaion environment, each vGPU requires portions HW
resources, including aperture, hidden GM space, and fence registers.
When creating a vGPU, GVT-g will request these HW resources from host,
and return them to host after a vGPU is destroyed.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
gen4/vlv/chv all use the same bits in pipestat to enable the vblank
interrupt, so they can share the same callbacks to enable/disable.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161007194953.15616-1-chris@chris-wilson.co.uk
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We want to read 3 bytes here, but because the parenthesis are in the
wrong place we instead read:
sizeof(intel_dp->edp_dpcd) == sizeof(intel_dp->edp_dpcd)
which is one byte.
Fixes: fe5a66f91c ("drm/i915: Read PSR caps/intermediate freqs/etc. only once on eDP")
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: <drm-intel-fixes@lists.freedesktop.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161013085508.GJ16198@mwanda
If the user requests a mappable binding to the global GTT, we will first
unbind an existing mapping if it doesn't match. We will unbind even if
there is no possibility that the object can fit in the mappable
aperture. This may lead to a ping-pong migration of the object, for
example igt/gem_exec_big.
v2: Comment upon the reasoning, or lack thereof!, behind the choice of
magic numbers.
Testcase: igt/gem_exec_big
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20161013085504.30705-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com
Mika wanted to know what requests were pending at the time of a hang as
we now track which requests we have submitted to the hardware.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161013101815.26978-1-chris@chris-wilson.co.uk
Make struct video_levels and struct tv_mode use data types
of sufficient width to save approximately one kilobyte in
the .rodata section.
v2: Do not align struct members. (Jani Nikula, Joonas Lahtinen)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476353366-13931-1-git-send-email-tvrtko.ursulin@linux.intel.com
Use types of more appropriate size in struct
intel_watermark_params to save 512 bytes of .rodata.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Pack the struct _sdvo_cmd_name to save 736 bytes of .rodata.
This is fine since the name pointers are used only for debug.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas 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: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Currently resuming on HSW from S3 pm_test/devices state leads to an
unrecoverable GPU hang. Resetting the GPU during suspend fixes this. For
a full S3 cycle this change only means the reset happens earlier (before
reaching S3). For S4 the reset will happen now both during the freeze
and quiesce phases, which is a benefit since it will guarantee that the
GPU is idle before creating and loading the hibernation image.
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1476283597-580-1-git-send-email-imre.deak@intel.com
Treat a framebuffer reference with the same priority as an active
reference whilst shrinking. Framebuffers are likely to be reused and
typically cost more to migrate to and from GPU memory (on LLC
architectures we need to clflush), so defer the temptation to purge them
during a kswapd run until we have run out of cheap buffers.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: John Harrison <john.c.harrison@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012124824.23521-1-chris@chris-wilson.co.uk
The current meaning of whether an object has a GGTT vma is very
ill-defined (and note we don't check for any partials either), it just
means that at some point it was in the GGTT but it may not be now. The
information we really care about here is whether it is taking up
precious mappable aperture space. This is the obj->fault_mappable flag.
We have a redundant long form reprinting of this information, so remove
that in favour of the compact flag.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012114827.17031-2-chris@chris-wilson.co.uk
Our error states are quickly growing, pinning kernel memory with them.
The majority of the space is taken up by the error objects. These
compress well using zlib and without decode are mostly meaningless, so
encoding them does not hinder quickly parsing the error state for
familiarity.
v2: Make the zlib dependency optional
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-6-chris@chris-wilson.co.uk
Leave all the pretty printing to userspace and simplify the error
capture to only have a single common object printer. It makes the kernel
code more compact, and the refactoring allows us to apply more complex
transformations like compressing the output.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-5-chris@chris-wilson.co.uk
Since the GTT provides universal access to any GPU page, we can use it
to reduce our plethora of read methods to just one. It also has the
important characteristic of being exactly what the GPU sees - if there
are incoherency problems, seeing the batch as executed (rather than as
trapped inside the cpu cache) is important.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-4-chris@chris-wilson.co.uk
The error state is purposefully racy as we expect it to be called at any
time and so have avoided any locking whilst capturing the crash dump.
However, with multi-engine GPUs and multiple CPUs, those races can
manifest into OOPSes as we attempt to chase dangling pointers freed on
other CPUs. Under discussion are lots of ways to slow down normal
operation in order to protect the post-mortem error capture, but what it
we take the opposite approach and freeze the machine whilst the error
capture runs (note the GPU may still running, but as long as we don't
process any of the results the driver's bookkeeping will be static).
Note that by of itself, this is not a complete fix. It also depends on
the compiler barriers in list_add/list_del to prevent traversing the
lists into the void. We also depend that we only require state from
carefully controlled sources - i.e. all the state we require for
post-mortem debugging should be reachable from the request itself so
that we only have to worry about retrieving the request carefully. Once
we have the request, we know that all pointers from it are intact.
v2: Avoid drm_clflush_pages() inside stop_machine() as it may use
stop_machine() itself for its wbinvd fallback.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-3-chris@chris-wilson.co.uk
We currently capture the GPU state after we detect a hang. This is vital
for us to both triage and debug hangs in the wild (post-mortem
debugging). However, it comes at the cost of running some potentially
dangerous code (since it has to make very few assumption about the state
of the driver) that is quite resource intensive.
This patch introduces both a method to disable error capture at runtime
(for users who hit bugs at runtime and need a workaround) and to disable
error capture at compiletime (for realtime users who want to minimise
any possible latency, and never require error capture, saving ~30k of
code). The cost is that we now have to be wary of (and test!) a kconfig
flag and a module parameter. The effect of the module parameter is easy
to verify through code inspection and runtime testing, but a kconfig flag
needs regular compile checking.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@linux.intel.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-2-chris@chris-wilson.co.uk
In the next patch, I want to conditionally compile i915_gpu_error.c and
that requires moving the functions used by debug out of
i915_gpu_error.c!
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-1-chris@chris-wilson.co.uk
Remove never used BSM{,_MASK}. BSM_MASK #define also causes a warning.
include/drm/i915_drm.h:96:34: warning: result of ‘65535 << 20’
requires 37 bits to represent, but ‘int’ only has 32 bits
[-Wshiftoverflow=]
#define INTEL_BSM_MASK (0xFFFF << 20)
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1476256734-6457-1-git-send-email-joonas.lahtinen@linux.intel.com
It's been over two months, git definitely lost it's marbles. Conflicts
resolved by picking our version, plus manually checking the diff with
the parent in drm-intel-next-queued to make sure git didn't do
anything stupid. It did, so I removed 2 occasions where it
double-inserted a bit of code. The diff is now just
- kernel-doc changes
- drm format/name changes
- display-info changes
so looks all reasonable.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Just flushing out my -misc queue. Slightly important are the prime
refcount/unload fixes from Chris.
There's also the reservation stuff from Chris still pending, and Sumits
hasn't landed that yet. Might get another pull for that, but pls don't
hold up the main pull for it ;-)
* tag 'topic/drm-misc-2016-10-11' of git://anongit.freedesktop.org/drm-intel:
drm/crtc: constify drm_crtc_index parameter
drm: use the right function name in documentation
drm: Release resources with a safer function
drm: Fix up kerneldoc for new drm_gem_dmabuf_export()
drm/bridge: Drop drm_connector_unregister and call drm_connector_cleanup directly
drm/fb-helper: fix sphinx markup for DRM_FB_HELPER_DEFAULT_OPS
drm/bridge: Add RGB to VGA bridge support
drm/prime: Take a ref on the drm_dev when exporting a dma_buf
drm/prime: Pass the right module owner through to dma_buf_export()
drm/bridge: Call drm_connector_cleanup directly
drm: simple_kms_helper: Add prepare_fb and cleanup_fb hooks
drm: Release resources with a safer function
If we want to know how many pages a VMA spans, we can use vma_pages() to
find out. We have one such invocation inside our faulthandler, so
convert it. (We have two other that want the size in bytes rather than
pages, food for future thought.)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20161011090656.29554-1-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
commit 1625e7e549 ("drm/i915: make compact dma scatter lists creation
work with SWIOTLB backend") took a heavy handed approach to undo the
scatterlist compaction in the face of SWIOTLB. (The compaction hit a bug
whereby we tried to pass a segment larger than SWIOTLB could handle.) We
can be a little more intelligent and try compacting the scatterlist up
to the maximum SWIOTLB segment size (when using SWIOTLB).
v2: Tidy sg_mark_end() and cpp
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
CC: Imre Deak <imre.deak@intel.com>
CC: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161011082021.14606-2-chris@chris-wilson.co.uk
When we notice the system under memory pressure, we try to evict some
driver pages before asking the VM to shrink all caches. As a final step
in that process, we tried to evict everything, including active buffers.
This is harming ourselves, and we can mix shrinking all caches as well
as our residual buffers (after the first pass of trying to shrink just
our own buffers).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161011082021.14606-1-chris@chris-wilson.co.uk
The conflict resolution of v4.8-rc8 backmerge to drm-next pulled back in
a few lines of dead code due to the code movement around
i915_gem_reset(), fix that up.
Fixes: ca09fb9f60 ("Merge tag 'v4.8-rc8' into drm-next")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161010125017.23911-1-chris@chris-wilson.co.uk
We reserve space in the GuC workqueue for submitting the request in the
future. However, if we fail to construct the request, we need to give
that reserved space back to the system.
Fixes: dadd481bfe ("drm/i915/guc: Prepare for nonblocking execbuf submission")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97978
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161007065327.24515-4-chris@chris-wilson.co.uk
(cherry picked from commit 5ba899082c)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Along with the interrupt, we want to restore the fake-irq and
wait-timeout detection. If we use the breadcrumbs interface to setup the
interrupt as it wants, the auxiliary timers will also be restored.
v2: Cancel both timers as well, sanitize the IMR.
Fixes: 821ed7df6e ("drm/i915: Update reset path to fix incomplete requests")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161007065327.24515-3-chris@chris-wilson.co.uk
(cherry picked from commit ad07dfcddf)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
If we run out of enough aperture space to fit the entire object, we
fallback to trying to insert a single page. However, if that also fails,
we currently fail to userspace with an unexpected ENOSPC. (ENOSPC means
to userspace that their batch could not be fitted within the GTT.) Prior
to commit e8cb909ac3 ("drm/i915: Fallback to single page GTT
mmappings for relocations") the approach is to fallback to using the
slow CPU relocation path in case of iomapping failure, and that is the
behaviour we need to restore.
Fixes: e8cb909ac3 ("drm/i915: Fallback to single page GTT mmappings...")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98101
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161007065327.24515-2-chris@chris-wilson.co.uk
(cherry picked from commit d7f7633557)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
In order not to trigger hangcheck on a idle-but-waiting engine, we need
to distinguish between the pending request queue and the actual
execution queue. This is done later in "drm/i915: Enable multiple
timelines" but for now we need a temporary fix to prevent blaming the
wrong engine for a GPU hang.
(Note that this causes a temporary subtle change in how we decide when
to allow a waitboost to be re-awarded back to the waiter, the temporary
effect is that if the wait is upon the most current execution the wait
is given for free, instead of checking to see if the client stalled
itself. This will be repaired in "drm/i915: Enable multiple timelines".)
Fixes: 0a046a0e93 ("drm/i915: Nonblocking request submission")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98104
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161007065327.24515-1-chris@chris-wilson.co.uk
(cherry picked from commit 8687b3ec85)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Allow returning "connected" or "unknown" connector status for DP branch
devices that don't have an EDID. Currently we'd claim the thing as
"disconnected" if there is no EDID.
This stuff used to broken already, I think, but it got more broken by
commit f21a21983e ("drm/i915: Splitting intel_dp_detect")
Cc: Damien Cassou <damien@cassou.me>
Cc: freedesktop.org@gp.mailgun.org
Cc: Arno <blouin.arno@gmail.com>
Cc: Shubhangi Shrivastava <shubhangi.shrivastava@intel.com>
Cc: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Cc: stable@vger.kernel.org
Tested-by: Arno <blouin.arno@gmail.com>
Fixes: f21a21983e ("drm/i915: Splitting intel_dp_detect")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83348
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1475481316-8194-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>
(cherry picked from commit 5cb651a795)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Zhi Wang