It is very common for an i2c device to require a small 1 or 2 byte write
followed by a read.  For example, when reading from an i2c EEPROM it is
common to write and address, offset or index followed by a reading some
values.

The i915 gmbus controller provides a special "INDEX" cycle for performing
such a small write followed by a read.  The INDEX can be either one or two
bytes long.  The advantage of using such a cycle is that the CPU has
slightly less work to do once the read with INDEX cycle is started.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The i915 is only able to generate a STOP cycle (i.e. finalize an i2c
transaction) during a DATA or WAIT phase.  In other words, the
controller rejects a STOP requested as part of the first transaction in a
sequence.

Thus, for the first transaction we must always use a WAIT cycle, detect
when the device has finished (and is in a WAIT phase), and then either
start the next transaction, or, if there are no more transactions,
generate a STOP cycle.

Note: Theoretically, the last transaction of a multi-transaction sequence
could initiate a STOP cycle.  However, this slight optimization is left
for another patch.  We return -ETIMEDOUT if the hardware doesn't
deactivate after the STOP cycle.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
[danvet: added comment to the code that gmbus can't generate STOP on
the very first cycle.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The GMBUS controller can report a NAK condition while a transaction is
still active. If the driver is fast enough, and the bus is slow enough,
the driver may clear the NAK condition while the controller is still
busy, resulting in a confused GMBUS controller.  This will leave the
controller in a bad state such that the next transaction may fail.

Also, return -ENXIO if a device NAKs a transaction.

Note: this patch also refactors gmbus_xfer to remove the "done" label.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The GMBUS controller GMBUS3 register is double-buffered.  Take advantage
of this  by writing two 4-byte words before the first wait for HW_RDY.
This helps keep the GMBUS controller from becoming idle during long writes.

In fact, during experiments using the GMBUS interrupts, the HW_RDY
interrupt would only trigger for transactions >4 bytes after 2 writes
to GMBUS3.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

A common method of probing an i2c bus is trying to do a zero-length write.
Handle this case by checking the length first before decrementing it.

This is actually important, since attempting a zero-length write is one
of the ways that i2cdetect and i2c_new_probed_device detect whether
there is device present on the bus with a given address.
Signed-off-by: NDaniel Kurtz <djkurtz@chromium.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just noticed this while verifying the VGA disable code.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In theory this will have performance and power improvements. Performance
because we don't need to stall when the scanout BO is busy, and power
because we don't have to stall when the BO is busy (and the ring can
even go to sleep if the HW supports it).

v2:
squash 2 patches into 1 (me)
un-inline the enable_semaphores function (Daniel)
remove comment about SNB hangs from i915_gem_object_sync (Chris)
rename intel_enable_semaphores to i915_semaphore_is_enabled (me)
removed page flip comment; "no why" (Chris)

To address other comments from Daniel (irc):
update the comment to say 'vt-d is crap, don't enable semaphores'
  - I think you misinterpreted Chris' comment, it already exists.
checking out whether we can pageflip on the render ring on ivb (didn't
work on early silicon)
  - We don't want to enable workarounds for early silicon unless we have
    to.
  - I can't find any references in the docs about this.
optionally use it if the fb is already busy on the render ring
  - This should be how the code already worked, unless I am
    misunderstanding your meaning.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

By simplifying the rules to calling get_fence when writing to the
through the GTT in a tiled manner, and calling put_fence before writing
to the object through the GTT in a linear manner, the code becomes
clearer and there is less chance of making a mistake.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
[danvet: fixed up conflict with ppgtt code and spelling in a new
comment.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

RC6 residency should be in intervals of 1.28us, and the counter wraps.
Here is an example using awk to get the various RC6 and RC6+ residency
times in seconds, since boot.

cat /sys/kernel/debug/dri/0/i915_drpc_info  | grep residency | awk -F':' -F' '  '{print $5 * 1.28 / 1000000}'

This is primarily for QA, but has other applications as well. An
upcoming patch to add interfaces should be more interesting to
application developers.

v2: move comment to the correct place

v3: display with %u instead of %d, for Ouping

CC: Ouping Zhang <ouping.zhang@intel.com>
Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Daniel Vetter wrote
First pull request for 3.5-next, slightly large than usual because new
things kept coming in since the last pull for 3.4.
Highlights:
- first batch of hw enablement for vlv (Jesse et al) and hsw (Eugeni). pci
 ids are not yet added, and there's still quite a few patches to merge
 (mostly modesetting). To make QA easier I've decided to merge this stuff
 in pieces.
- loads of cleanups and prep patches spurred by the above. Especially vlv
 is a real frankenstein chip, but also hsw is stretching our driver's
 code design. Expect more to come in this area for 3.5.
- more gmbus fixes, cleanups and improvements by Daniel Kurtz. Again,
 there are more patches needed (and some already queued up), but I wanted
 to split this a bit for better testing.
- pwrite/pread rework and retuning. This series has been in the works for
 a few months already and a lot of i-g-t tests have been created for it.
 Now it's finally ready to be merged.  Note that one patch in this series
 touches include/pagemap.h, that patch is acked-by akpm.
- reduce mappable pressure and relocation throughput improvements from
 Chris.
- mmap offset exhaustion mitigation by Chris Wilson.
- a start at figuring out which codepaths in our messy dri1/ums+gem/kms
 driver we actually need to support by bailing out of unsupported case.
 The driver now refuses to load without kms on gen6+ and disallows a few
 ioctls that userspace never used in certain cases. More of this will
 definitely come.
- More decoupling of global gtt and ppgtt.
- Improved dual-link lvds detection by Takashi Iwai.
- Shut up the compiler + plus fix the fallout (Ben)
- Inverted panel brightness handling (mostly Acer manages to break things
 in this way).
- Small fixlets and adjustements and some minor things to help debugging.

Regression-wise QA reported quite a few issues on ivb, but all of them
turned out to be hw stability issues which are already fixed in
drm-intel-fixes (QA runs the nightly regression tests on -next alone,
without -fixes automatically merged in). There's still one issue open on
snb, it looks like occlusion query writes are not quite as cache coherent
as we've expected. With some of the pwrite adjustements we can now
reliably hit this. Kernel workaround for it is in the works."

* 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel: (101 commits)
  drm/i915: VCS is not the last ring
  drm/i915: Add a dual link lvds quirk for MacBook Pro 8,2
  drm/i915: make quirks more verbose
  drm/i915: dump the DMA fetch addr register on pre-gen6
  drm/i915/sdvo: Include YRPB as an additional TV output type
  drm/i915: disallow gem init ioctl on ilk
  drm/i915: refuse to load on gen6+ without kms
  drm/i915: extract gt interrupt handler
  drm/i915: use render gen to switch ring irq functions
  drm/i915: rip out old HWSTAM missed irq WA for vlv
  drm/i915: open code gen6+ ring irqs
  drm/i915: ring irq cleanups
  drm/i915: add SFUSE_STRAP registers for digital port detection
  drm/i915: add WM_LINETIME registers
  drm/i915: add WRPLL clocks
  drm/i915: add LCPLL control registers
  drm/i915: add SSC offsets for SBI access
  drm/i915: add port clock selection support for HSW
  drm/i915: add S PLL control
  drm/i915: add PIXCLK_GATE register
  ...

Conflicts:
	drivers/char/agp/intel-agp.h
	drivers/char/agp/intel-gtt.c
	drivers/gpu/drm/i915/i915_debugfs.c

On coherent systems (not-AGP) the IB should be in cached memory so should
be just as fast, so we can avoid copying to temporary pages and just use it
directly.

provides minor speedups on rv530: gears ~1820->1860, ipers: 29.9->30.6,
but always good to use less CPU if we can.

v3: cleanup unneeded bits.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This closes a race seen with kexec where we enable PCI bus mastering
but the card has been reinitialised fully yet.

This was previously fixed by a patch from Jerome, but this should
close the race completely.

v2: add SI support as suggested by Alex.
Reported-and-tested-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: NDave Airlie <airlied@redhat.com>

I made a mistake, please forgive me.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=48254Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When booting with EFI, Apple botched this one up.

v2: Switch the quirk dmesg output to DRM_INFO.
v3: Actually git add the new things ...
Tested-by: NAustin Lund <austin.lund@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42842Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

And add informational dmesg output where it does not yet exist.

In case a quirk matches too much, this information is crucial for
debugging such a bug report.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It exists way back to gen2, bug got moved around on gen4 a bit.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Reported-and-tested-by: Bo Wang < bo.b.wang@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=36997Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Ums is already disabled, but on ilk we can additionally disable gem
initialization when using user mode setting. Upstream never support
ilk without kernel modesetting and not even the RHEL ilk ums backport
needs gem - that driver is based on xf86-video-intel version 2.2,
which is pre-gem.
Reviewed-by: NAdam Jackson <ajax@redhat.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Spurred by an irc discussion, let's start to clear up which parts of
our kms + ums/gem + ums/dri1 + vbios/dri1 kernel driver pieces
userspace in the wild actually uses.

The idea is that we introduce checks at entry-points (module load
time, ioctls, ...) first and then reap any obviously dead code in a
second step.

As a first step refuse to load without kms on chips where userspace
never supported ums. Now upstream hasn't supported ums on ilk, ever.
But RHEL had the great idea to backport the kms support to their ums
driver.

Cc: Dave Airlie <airlied@gmail.com>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

vlv, ivb and snb all share the gen6+ gt irq handling. 3 copies of the
same stuff is a bit much, so extract it into a little helper.

Now ilk has a different gt irq handling than snb, but shares the same
irq handler (due to the similar display block). So also extract the
ilk gt irq handling to clearly separate these two things.

Nice side effect of this is that we can complete Ben Widawsky's gen6+
irq bit #define cleanup and call the render irq also with the GEN6
alias. Beforehand that code was shared with ilk, and neither option
really made much sense.

As a bonus this enables the error interrupt handling lifted from the
vlv code on snb and ivb, too.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Antagonized-by: NBen Widawsky <ben@bwidawsk.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Top-level interrupt bits are usually found in the display block. It
therefore makes sense to use HAS_PCH_SPLIT in i915_irq.c

But the irq stuff in intel_ring.c only concerns itself with render
core/gt-level interrupt sources. It therefore makes more sense to
switch based on gpu gen.

Kills a vlv special case.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This got copy-pasted from an older version. The newer kinds of
workarounds don't need this anymore.

Shame on me for not noticing when picking up the vlv irq patch.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We can now open-code the get/put irq functions as they were just
abstracting single register definitions.

It would be nice to merge this in with the IRQ handling code... but that
is too much work for me at present. In addition I could probably
collapse this in to a lot of the Ironlake stuff, but I don't think it's
worth the potential regressions.

This patch itself should not effect functionality.

CC: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

- gen6 put/get only need one argument
    rflags and gflags are always the same (see above explanation)
- remove a couple redundantly defined IRQs
- reordered some lines to make things go in descending order

Every ring has its own interrupts, enables, masks, and status bits that
are fed into the main interrupt enable/mask/status registers. At one
point in time it seemed like a good idea to make our functions support
the notion that each interrupt may have a different bit position in the
corresponding register (blitter parser error may be bit n in IMR, but
bit m in blitter IMR). It turned out though that the HW designers did us
a solid on Gen6+ and this unfortunate situation has been avoided. This
allows our interrupt code to be cleaned up a bit.

I jammed this into one commit because there should be no functional
change with this commit, and staging it into multiple commits was
unnecessarily artificial IMO.

CC: Chris Wilson <chris@chris-wilson.co.uk>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet:
- fixed up merged conflict with vlv changes.
- added GEN6 to GT blitter bit, we only use it on gen6+.
- added a comment to both ring irq bits and GT irq bits that on gen6+
  these alias.
- added comment that GT_BSD_USER_INTERRUPT is ilk-only.
- I've got confused a bit that we still use GT_USER_INTERRUPT on ivb
  for the render ring - but this goes back to ilk where we have only
  gt interrupt bits and so we be equally confusing if changed.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

DDIA is detected via the DDI_BUF_CTL registers bit 0, but for DDIB, DDIC
and DDID we need to consult SFUSE_STRAP values.
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Watermark line time registers for display low power watermark.

v2: improve bit names as suggested by Chris Wilson
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The WR PLL can drive the DDI ports at fixed frequencies for HDMI, DVI, DP
and FDI.
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Those are used to control the display core clock.

v2: change the enable bit setting, spotted by Rodrigo Vivi.
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Different registers are identified by their target id and offset. To
simplify their programming, they are called as <RegisterName><TargetId>.
For example, SSCCTL register accessed through SBI at target id 6 and
offset 0c is called SBI_SSCCTL6.
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Multiple clocks can drive different outputs.

v2: use the port enums to access individual ports

v1 Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This PLL control can drive DDI ports at desired frequencies for
DisplayPort and FDI connections.
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Pixel clock gating control for Lynx point.
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Those are responsible for the Sideband Interface programming.

v2: rename SBI bits to better reflect their meaning
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Those registers are used to train DDI buffer translations for each link
type.

v2: access each port registers through the DDI_BUF_TRANS macro
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is one instance of those registers for each DDI port.

v2: access registers via the DDI_BUF_CTL() macro
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is one set of those registers for each port.
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is one set of those registers for each pipe.

v2: use port enum to access individual registers
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is one set of such registers for each pipe (A/B/C/EDP).

v2: update to use DDI PORTS enum

v1 Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There are 5 DDI ports on Haswell. Port A is always enabled, and is the one
connected to eDP, and Port E is the one that can be connected to the PCH
using FDI protocol.  Ports B, C, D and E can be used for digital outputs.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This defines the registers used by different power wells.
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>