Backlight data and registers are fiddled through LVDS/eDP modeset
enable/disable hooks, backlight sysfs files, asle interrupts, and register
save/restore. Protect the backlight related registers and driver private
fields using a spinlock.
The locking in register save/restore covers a little more than is strictly
necessary, including non-modeset case, for simplicity.
v2: Cover register access, save/restore, i915_read_blc_pwm_ctl() and code
paths leading there.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Because the register does not exist on LPT. The interesting fact is
that reading/writing PCH_LVDS on LPT does *not* give us "unclaimed
register" messages, but the register value is always 0.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We still rely on a few LVDS bits, but restoring the enable bit can cause
trouble at this point, so don't.
v2: use the right mask to prevent restore (Daniel)
conditionalize on KMS support (Denial)
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The VGACNTRL register has moved around between different platforms.
To handle the differences add i915_vgacntrl_reg() which returns the
correct offset for the VGACNTRL register.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Note that this slightly changes the order, but we only move it within
the block of registers that restore encoder state. Specifically LVDS
is now restored after DP, whereas previously it was done before.
Legacy vga is still restored afterwards, which seems to be the
important thing (if there's anything important in this restore
ordering at all).
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The only thing we really care about that it is off. To do so, reuse
the recently created i915_redisable_vga function, which is already
used to put obnoxious firmware into check on lid reopening.
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Similarly to how i915_dma.c is shaping up to be the dungeon hole for
all things supporting dri1, create a new one to hide all the crazy
things which are only really useful for ums support. Biggest part is
the register suspend/resume support.
Unfortunately a lot of it is still intermingled with bits and pieces
we might still need, so needs more analysis and needs to stay in
i915_suspend.c for now.
Reviewed-by: Imre Deak <imre.deak@intel.com>
v2: s/modeset_reg/display_reg/ as suggested by Imre, to avoid
confusion between the kernel modeset code and display save/restore to
support ums.
v3: Fixup alphabetical order in the Makefile, spotted by Chris Wilson.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
That way the control flow is clearer, and it prepares the stage
to extract these ums functions and hide them somewhere.
There's still tons of display stuff outside of these, but that
requires more work.
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Because the register does not exist in gen5+.
This patch solves "unclaimed register" messages on Haswell after
suspend/resume.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now that we always restore the HWS registers (both physical and GTT
virtual addresses) when re-initialising the rings, we can eliminate the
superfluous save/restore of the register across suspend and resume.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
dev_priv has grown way too big, and grouping memebers into substructs
and moving them out of line helps re-gain some overview.
Unfortunatley I couldn't just call the substruct save and drop the prefix, since
that will make most member names clash with registers #defines. Changes in
i915_drv.h done by hand, everything else changed with
s/\<save\([A-Z]*\)/regfile.save\1/ in vim.
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v3.7-rc2' into drm-intel-next-queued
Linux 3.7-rc2
Backmerge to solve two ugly conflicts:
- uapi. We've already added new ioctl definitions for -next. Do I need to say more?
- wc support gtt ptes. We've had to revert this for snb+ for 3.7 and
also fix a few other things in the code. Now we know how to make it
work on snb+, but to avoid losing the other fixes do the backmerge
first before re-enabling wc gtt ptes on snb+.
And a few other minor things, among them git getting confused in
intel_dp.c and seemingly causing a conflict out of nothing ...
Conflicts:
drivers/gpu/drm/i915/i915_reg.h
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_dp.c
drivers/gpu/drm/i915/intel_modes.c
include/drm/i915_drm.h
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We now no longer rely on this.
This is step 1 on a long journey to rid us of the save/restore
madness, which tends to lightly paper over many issues, and cause
tons of bad things itself ...
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: satisfy Paulo's ocd and drop the needless braces.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We already do that as part of the ringbuffer re-setup at resume time.
Furthermore the register offset has moved on gen6+ around quite a bit,
and on ilk/gm45 we also need to restore the HWS reg for the bsd ring,
not just the render ring.
So again in kms mode this is only confusing a best, hence don't
bother.
v2: Fixup logic, noticed by Paulo Zanoni.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We already call drm_irq_install/uninstall at the right time, which
will set up the irq registers with the correct values (through the
preinstall hooks).
For kms this is at best harmless, in the worst case we get an
interrupt when we don't really expect it.
v2: Fixup the logic, noticed by Paulo Zanoni.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We completely compute these anew in each modeset, hence we don't rely
on them containing anything valid after resume.
To avoid breaking any ums setup due to reordering of the reads/writes
simply don't reorder anything, but bracket the reads/writes into if
(!kms) conditionals. More churn, but safer.
v2: Fixup the logic, noticed by Paulo Zanoni.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Convert #include "..." to #include <path/...> in drivers/gpu/.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Remove redundant DRM UAPI header #inclusions from drivers/gpu/.
Remove redundant #inclusions of core DRM UAPI headers (drm.h, drm_mode.h and
drm_sarea.h). They are now #included via drmP.h and drm_crtc.h via a preceding
patch.
Without this patch and the patch to make include the UAPI headers from the core
headers, after the UAPI split, the DRM C sources cannot find these UAPI headers
because the DRM code relies on specific -I flags to make #include "..." work
on headers in include/drm/ - but that does not work after the UAPI split without
adding more -I flags.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
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Merge tag 'v3.5-rc7' into drm-next
Merge Linus tree into drm to fixup conflicts in radeon code for further
testing before upstream merge.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Conflicts:
drivers/gpu/drm/i915/i915_dma.c
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/radeon/radeon_gart.c
... instead of calling each one for each generation indiviudally.
Notice that we've already managed to be inconsistent, the resume path
is missing an IS_VLV check. As a nice benefit we can mark all the
platform specific enable/disable functions as static and hide them in
intel_pm.c
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This patch fixes the problem on some HP desktop machines with eDP
which give blank screens after S3 resume.
It turned out that BLC_PWM_CPU_CTL must be written after
BLC_PWM_CPU_CTL2. Otherwise it doesn't take effect on these
SNB machines.
Tested with 3.5-rc3 kernel.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49233
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently we call gen6_enable_rps() (which writes into the per-ring
register mmio space) from intel_modeset_init_hw() which is called before
we initialise the rings. If we defer intel_modeset_init_hw() until
afterwards (in the intel_modeset_gem_init() phase) all is well.
v2: Rectify ordering of gem vs display HW init upon resume. (Daniel)
v3: Fix up locking. (Paulo)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Smash Paulo's locking fix onto Chris' patch.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
PCH PLLs aren't required for outputs on the CPU, so we shouldn't just
treat them as part of the pipe.
So split the code out and manage PCH PLLs separately, allocating them
when needed or trying to re-use existing PCH PLL setups when the timings
match.
v2: add num_pch_pll field to dev_priv (Daniel)
don't NULL the pch_pll pointer in disable or DPMS will fail (Jesse)
put register offsets in pll struct (Chris)
v3: Decouple enable/disable of PLLs from get/put.
v4: Track temporary PLL disabling during modeset
v5: Tidy PLL initialisation by only checking for num_pch_pll == 0 (Eugeni)
v6: Avoid mishandling allocation failure by embedding the small array of
PLLs into the device struct
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44309
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> (up to v2)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v3+)
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Tested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
After a gpu reset we need to re-init some of the hw state we only
initialize when modeset is enabled, like rc6, hw contexts or render/GT
core clock gating and workaround register settings.
Note that this patch has a small change in the resume code:
- rc6 on gen6+ is only restored for the modeset case (for more
consistency with other callsites). This is no problem because recent
kernels refuse to load drm/i915 without kms on gen6+
- rc6/emon on ilk is only restored for the modeset case. This is no
problem because rc6 is disabled by default on ilk, and ums on ilk
has never really been a supported option outside of horrible rhel
backports.
v2: Chris Wilson noticed that we not only fail to restore the clock
gating settings after gpu reset.
v3: Move the call to modeset_init_hw in _reset out of the
struct_mutext protected area - other callers don't hold it, too.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We don't need to check 3rd pipe specifically, as it shares PLL with some
other one.
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
This is also handled by i915_reg.h, so just reuse this trick to reduce
universe entropy.
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Cyril Brulebois <kibi@debian.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
So don't forget to restore them on resume and dump them into
the error state.
Cc: stable@kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>
Various issues involved with the space character were generating
warnings in the checkpatch.pl file. This patch removes most of those
warnings.
Signed-off-by: Akshay Joshi <me@akshayjoshi.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
The clock gating functions are only assigned under KMS, so don't try
to call them under UMS.
Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Justin P. Mattock <justinmattock@gmail.com>
At least on a Lenovo X220 the HPD bits of this are enabled at boot but
cleared after resume, which means plug interrupts stop working.
This also happens to fix DP displays re-lighting on resume. I'm quite
certain that's an accident: the first DP link train inevitably fails on
that machine, and it's only serendipity that we're getting multiple plug
interrupts and the second train works. But I shall take my victories
where I get them.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Tested-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
As the enable/disable routines will be gain additional complexity in
future patches, it is necessary that all callers do not bypass the
generic interface by calling into the chipset routines directly. to do
this we make the chipset routines static, so there is no choice.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
Lots of register access in these functions, some of which requires the
struct mutex.
These functions now hold the struct mutex across the calls to
i915_save_display and i915_restore_display, and so the internal mutex
calls in those functions have been removed. To ensure that no-one else
was calling them (and hence violating the new required locking
invarient), those functions have been made static.
gen6_enable_rps locks the struct mutex, and so i915_restore_state
unlocks the mutex around calls to that function.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Keith Packard <keithp@keithp.com>
The ring frequency scaling table tells the PCU to treat certain GPU
frequencies as if they were a given CPU frequency for purposes of
scaling the ring frequency. Normally the PCU will scale the ring
frequency based on the CPU P-state, but with the table present, it will
also take the GPU frequency into account.
The main downside of keeping the ring frequency high while the CPU is
at a low frequency (or asleep altogether) is increased power
consumption. But then if you're keeping your GPU busy, you probably
want the extra performance.
v2:
- add units to debug table header (from Eric)
- use tsc_khz as a fallback if the cpufreq driver doesn't give us a freq
(from Chris)
v3:
- fix comments & debug output
- remove unneeded force wake get/put
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
The lock must be held for the saving and restoring of VGA state.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
CC: Alexander Zhaunerchyk <alex.vizor@gmail.com>
CC: Andrey Rahmatullin <wrar@wrar.name>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>
Ibex Peak and CougarPoint already require a different setting (added
here), and future chips will likely follow that precedent.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This helps contain the mess to init_display() instead.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This reverts commit a7a75c8f70.
There are two different variations on how Intel hardware addresses the
"Hardware Status Page". One as a location in physical memory and the
other as an offset into the virtual memory of the GPU, used in more
recent chipsets. (The HWS itself is a cacheable region of memory which
the GPU can write to without requiring CPU synchronisation, used for
updating various details of hardware state, such as the position of
the GPU head in the ringbuffer, the last breadcrumb seqno, etc).
These two types of addresses were updated in different locations of code
- one inline with the ringbuffer initialisation, and the other during
device initialisation. (The HWS page is logically associated with
the rings, and there is one HWS page per ring.) During resume, only the
ringbuffers were being re-initialised along with the virtual HWS page,
leaving the older physical address HWS untouched. This then caused a
hang on the older gen3/4 (915GM, 945GM, 965GM) the first time we tried
to synchronise the GPU as the breadcrumbs were never being updated.
Reported-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Jan Niehusmann <jan@gondor.com>
Reported-by: Justin P. Mattock <justinmattock@gmail.com>
Reported-and-tested-by: Michael "brot" Groh <brot@minad.de>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's cleaned before saving and re-initialized after restoring.
So don't need to save/restore it. And also new chip has new address
for hardware status page register, don't write to old address.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
We had some conversions over to the _PIPE macros, but didn't get
everything. So hide the per-pipe regs with an _ (still used in a few
places for legacy) and add a few _PIPE based macros, then make sure
everyone uses them.
[update: remove usage of non-existent no-op macro]
[update 2: keep modesetting suspend/resume code, update to new reg names]
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[ickle: stylistic cleanups for checkpatch and taste]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cleanup several aspects of the rc6 code:
- misnamed intel_disable_clock_gating function (was only about rc6)
- remove commented call to intel_disable_clock_gating
- rc6 enabling code belongs in its own function (allows us to move the
actual clock gating enable call back into restore_state)
- allocate power & render contexts up front, only free on unload
(avoids ugly lazy init at rc6 enable time)
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[ickle: checkpatch cleanup]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Enabling RC6 implies setting a graphics context. Make sure we do that
only after the ring has been enabled, otherwise our ring commands will
hang.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Re-enable rc6 support on Ironlake for power savings. Adds a debugfs
file to check current RC state, adds a missing workaround for Ironlake
MI_SET_CONTEXT instructions, and renames MCHBAR_RENDER_STANDBY to
RSTDBYCTL to match the docs.
Keep RC6 and the power context disabled on pre-ILK. It only seems to
hang and doesn't save any power.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Manaul revert of 0cdab21f9a, just to
remove the call to disable the clock gatings and powerctx before
suspend.
Peter Clifton bisected a suspend failure on his gme45 and found this to
be the culprit. As this was intended to be a fix for a similar suspend
failure for Ironlake (it didn't work), undoing this patch should have no
other side-effects.
Reported-and-tested-by: Peter Clifton <pcjc2@cam.ac.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Add an interrupt handler for switching graphics frequencies and handling
PM interrupts. This should allow for increased performance when busy
and lower power consumption when idle.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
With KMS, we can simply relinquish the fence when we idle the GPU and
reassign it upon first use.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Under KMS, restoring the cursor is handled upon modeswitch in order to
avoid enabling an undefined set of registers. At the moment, the cursor
is restored before the aperture and modes are fully setup causing some
invalid access during resume, such as:
PGTBL_ER: 0x00040000
Invalid GTT entry during Cursor Fetch
Fix this by only performing cursor register save/restore under UMS where
it is done in the correct sequence.
Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>