We already disallow initialition of gem in this case in the
corresponding ioctl, so don't bother setting up the gem support ring
functions in the legacy dri render ring init.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

They're indentical, so just kill one. Also give the other a prefix to
distinguish it from the gen6+ functions - this add_request function is
not really generic code.

v2: Fixup commit message as noted by Ben Widawsky.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we can, we should split them up in a way that makes some
sense and banishes the IS_ checks into init code.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

HW engineers have fixed this issue for ivb. Again, a nice cleanup
possible thanks to the more flexible ring initialization.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we have sensibly split up, we can nicely get rid of that ugly
is_gen5 check.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Inspired by Ben Widawsky's patch for gen6+. Now after restructuring
how we set up the ring vtables and parameters, we can do this right.

This kills the bsd specific get/put_irq functions, they're now the
same.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The waiter is always the ring itself (otherwise we'd have a decent
snafu in a callsite), so we can unify this easily.

Also give it the usual gen6_ prefix, in case anyone is foolish enough to
implement hw semaphores for gen5.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's not supported, and with the patch to refuse loading on gen6+
without kms enabled, there's also no way we can hit this.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just for consistency.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The same treatment for the bsd ring. Again, this will be split up
further by the irq rework.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Our hw is simply not well-designed enough that it neatly fits into
boxes. Everywhere else we set up vtables and similar things
dynamically using switch statements - it's simply much more flexible.

This is prep work to rework the pre-gen6 ring irq stuff - it'll add a
few more differences. With the current const struct templates, that
would be a mess.

This leads to some unfortunate duplication with the old dri1 code, but
we can reap that again because gen6 isn't actually supported there.
But that's for a separate patch.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Eventually we want to scale the ring size depending upon available
gtt space. For now just consolidate this instead of replicating it
over all ringbuffer templates.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We only ever enable/disable one interrupt (namely user_interrupts and
pipe_notify), so we don't need to track the interrupt masking state.

Also rename irq_enable to irq_enable_mask, now that it won't collide -
beforehand both a irq_mask and irq_enable_mask would have looked a bit
strange.
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Waiting for seqno-1 in our object synchronization code is an
implementation detail given how we've decided to do the waits within the
rest of our code.
Requested-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
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>

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>

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>

Ben Widawsky reported missed IRQ issues and this patch here helps.

We have one other missed IRQ report still left on snb, reported by QA:

https://bugs.freedesktop.org/show_bug.cgi?id=46145

This is _not_ a regression due to the forcewake voodoo though, it
started showing up before that was applied and has been on-and-off for
the past few weeks. According to QA this patch does not help. But the
missed IRQ is always from the blt ring (despite running piglit, so
also render activity expected), so I'm hopefully that this is an issue
with the blt ring itself.
Tested-by: NBen Widawsky <ben@bwidawsk.net>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

ValleyView has a new interrupt architecture; best to put it in a new set
of functions.  Also make sure the ring mask functions handle ValleyView.

FIXME: fix flipping; need to enable interrupts and call prepare/finish
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I have seen a number of "blt ring initialization failed" messages
where the ctl or start registers are not the correct value. Upon further
inspection, if the code just waited a little bit, it would read the
correct value. Adding the wait_for to these reads should eliminate the
issue.
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is a revert of 6aa56062.

This was originally introduced to workaround reads of the ringbuffer
registers returning 0 on SandyBridge causing hangs due to ringbuffer
overflow. The root cause here was reads through the GT powerwell require
the forcewake dance, something we only learnt of later. Now it appears
that reading the reported head position from the HWS is returning
garbage, leading once again to hangs.

For example, on q35 the autoreported head reports:
  [  217.975608] head now 00010000, actual 00010000
  [  436.725613] head now 00200000, actual 00200000
  [  462.956033] head now 00210000, actual 00210010
  [  485.501409] head now 00400000, actual 00400020
  [  508.064280] head now 00410000, actual 00410000
  [  530.576078] head now 00600000, actual 00600020
  [  553.273489] head now 00610000, actual 00610018
which appears reasonably sane. In contrast, if we look at snb:
  [  141.970680] head now 00e10000, actual 00008238
  [  141.974062] head now 02734000, actual 000083c8
  [  141.974425] head now 00e10000, actual 00008488
  [  141.980374] head now 032b5000, actual 000088b8
  [  141.980885] head now 03271000, actual 00008950
  [  142.040628] head now 02101000, actual 00008b40
  [  142.180173] head now 02734000, actual 00009050
  [  142.181090] head now 00000000, actual 00000ae0
  [  142.183737] head now 02734000, actual 00009050

In addition, the automatic reporting of the head position is scheduled
to be defeatured in the future. It has no more utility, remove it.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45492Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

By recording the location of every request in the ringbuffer, we know
that in order to retire the request the GPU must have finished reading
it and so the GPU head is now beyond the tail of the request. We can
therefore provide a conservative estimate of where the GPU is reading
from in order to avoid having to read back the ring buffer registers
when polling for space upon starting a new write into the ringbuffer.

A secondary effect is that this allows us to convert
intel_ring_buffer_wait() to use i915_wait_request() and so consolidate
upon the single function to handle the complicated task of waiting upon
the GPU. A necessary precaution is that we need to make that wait
uninterruptible to match the existing conditions as all the callers of
intel_ring_begin() have not been audited to handle ERESTARTSYS
correctly.

By using a conservative estimate for the head, and always processing all
outstanding requests first, we prevent a race condition between using
the estimate and direct reads of I915_RING_HEAD which could result in
the value of the head going backwards, and the tail overflowing once
again. We are also careful to mark any request that we skip over in
order to free space in ring as consumed which provides a
self-consistency check.

Given sufficient abuse, such as a set of unthrottled GPU bound
cairo-traces, avoiding the use of I915_RING_HEAD gives a 10-20% boost on
Sandy Bridge (i5-2520m):
  firefox-paintball  18927ms -> 15646ms: 1.21x speedup
  firefox-fishtank   12563ms -> 11278ms: 1.11x speedup
which is a mild consolation for the performance those traces achieved from
exploiting the buggy autoreported head.

v2: Add a few more comments and make request->tail a conservative
estimate as suggested by Daniel Vetter.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: resolve conflicts with retirement defering and the lack of
the autoreport head removal (that will go in through -fixes).]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We still have reports of missed irqs even on Sandybridge with the
HWSTAM workaround in place. Testing by the bug reporter gets rid of
them with the forcewake voodoo and no HWSTAM writes.

Because I've slightly botched the rebasing I've left out the ACTHD
readback which is also required to get IVB working. Seems to still
work on the tester's machine, so I think we should go with the more
minmal approach on SNB. Especially since I've only found weak evidence
for holding forcewake while waiting for an interrupt to arrive, but
none for the ACTHD readback.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45181
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45332
Tested-by: Nicolas Kalkhof nkalkhof()at()web.de
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently we reserve seqnos only when we emit the request to the ring
(by bumping dev_priv->next_seqno), but start using it much earlier for
ring->oustanding_lazy_request. When 2 threads compete for the gpu and
run on two different rings (e.g. ddx on blitter vs. compositor)
hilarity ensued, especially when we get constantly interrupted while
reserving buffers.

Breakage seems to have been introduced in

commit 6f392d54
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sat Aug 7 11:01:22 2010 +0100

    drm/i915: Use a common seqno for all rings.

This patch fixes up the seqno reservation logic by moving it into
i915_gem_next_request_seqno. The ring->add_request functions now
superflously still return the new seqno through a pointer, that will
be refactored in the next patch.

Note that with this change we now unconditionally allocate a seqno,
even when ->add_request might fail because the rings are full and the
gpu died. But this does not open up a new can of worms because we can
already leave behind an outstanding_request_seqno if e.g. the caller
gets interrupted with a signal while stalling for the gpu in the
eviciton paths. And with the bugfix we only ever have one seqno
allocated per ring (and only that ring), so there are no ordering
issues with multiple outstanding seqnos on the same ring.

v2: Keep i915_gem_get_seqno (but move it to i915_gem.c) to make it
clear that we only have one seqno counter for all rings. Suggested by
Chris Wilson.

v3: As suggested by Chris Wilson use i915_gem_next_request_seqno
instead of ring->oustanding_lazy_request to make the follow-up
refactoring more clearly correct. Also improve the commit message
with issues discussed on irc.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45181
Tested-by: Nicolas Kalkhof nkalkhof()at()web.de
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This was just to facilitate product enablement with pre-production hw.
Allows us to kill quite a bit of cruft.
Signed-off-by: NKenneth Graunke <kenneth@whitecape.org>
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

... and add a helpr function for the places where we want a flag.

This way we can use ring->id to index into arrays.

v2: Resurrect the missing beautification-space Chris Wilson noted.
I'm moving this space around because I'll reuse ring_str in the next
patch.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have always been using the wrong bit -- it's bit 12.  However, the
bit also doesn't do anything -- hardware has always accepted the
MI_FLUSH command even when it was specced not to.

Given that there is only one MI_FLUSH emitted in all of the driver
stack on gen6+ (in i965_video.c of the 2d driver, and it should be
using other code to do its flush instead), just remove the MI_FLUSH
enable instead of trying to fix it.
Signed-off-by: NEric Anholt <eric@anholt.net>
Reviewed-by: NKenneth Graunke <kenneth@whitecape.org>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit 42ff6572.

New forcewake voodoo makes this no longer necessary.
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NKeith Packard <keithp@keithp.com>

Two things seem to do the trick on my ivb machine here:
- prevent the gt from powering down while waiting for seqno
  notification interrupts by grabbing the force_wake in get_irq (and
  dropping it in put_irq again).
- ordering writes from the ring's CS by reading a CS register, ACTHD
  seems to work.

Only the blt&bsd ring on ivb seem to be massively affected by this,
but for paranoia do this dance also on the render ring and on snb
(i.e. all gpus with forcewake).

Tested with Eric's glCopyPixels loop which without this patch scores a
missed irq every few seconds.

This patch needs my forcewake rework to use a spinlock instead of
dev->struct_mutex.

After crawling through docs a lot I've found the following nugget:

Internal doc "SNB GT PM Programming Guide", Section 4.3.1:

"GT does not generate interrupts while in RC6 (by design)"

So it looks like rc6 and irq generation are indeed related.

v2: Improve the comment per Eugeni Dodonov's suggestion.

v3: Add the documentation snipped. Also restrict the w/a to ivb only
for -fixes, as suggested by Keith Packard.

Cc: stable@kernel.org
Cc: Eric Anholt <eric@anholt.net>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Eugeni Dodonov <eugeni.dodonov@intel.com>
Tested-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NKeith Packard <keithp@keithp.com>

In the pre-gem days with non-existing hangcheck and gpu reset code,
this timeout of 3 seconds was pretty important to avoid stuck
processes.

But now we have the hangcheck code in gem that goes to great length
to ensure that the gpu is really dead before declaring it wedged.

So there's no need for this timeout anymore. Actually it's even harmful
because we can bail out too early (e.g. with xscreensaver slip)
when running giant batchbuffers. And our code isn't robust enough
to properly unroll any state-changes, we pretty much rely on the gpu
reset code cleaning up the mess (like cache tracking, fencing state,
active list/request tracking, ...).

With this change intel_begin_ring can only fail when the gpu is
wedged, and it will return -EAGAIN (like wait_request in case the
gpu reset is still outstanding).

v2: Chris Wilson noted that on resume timers aren't running and hence
we won't ever get kicked out of this loop by the hangcheck code. Use
an insanely large timeout instead for the HAS_GEM case to prevent
resume bugs from totally hanging the machine.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NKeith Packard <keithp@keithp.com>

Previous to this commit, testing easily reproduced a failure where the
seqno would apparently arrive after the IRQ associated with it, with test programs as simple as:

for (;;) {
    glCopyPixels(0, 0, 1, 1);
    glFinish();
}

Various workarounds we've seen for previous generations didn't work to
fix this issue, so until new information comes in, replace the IRQ
waits on the BLT ring with polling.
Signed-off-by: NEric Anholt <eric@anholt.net>
Tested-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Acked-by: NKenneth Graunke <kenneth@whitecape.org>
Signed-off-by: NKeith Packard <keithp@keithp.com>

The docs say this is required for Gen7, and since the bit was added for
Gen6, we are also setting it there pit pf paranoia. Particularly as
Chris points out, if PIPE_CONTROL counts as a 3d state packet.

This was found through doc inspection by Ken and applies to Gen6+;
Reported-by: NKenneth Graunke <kenneth@whitecape.org>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NKeith Packard <keithp@keithp.com>

v2 by danvet: Use a new flag to flush the render target cache on gen6+
(hw reuses the old write flush bit), as suggested by Ben Widawsdy.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NKenneth Graunke <kenneth@whitecape.org>
[danvet: this seems to fix cairo-perf-trace hangs on my snb]
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NKeith Packard <keithp@keithp.com>

"STALL_AT_SCOREBOARD" is much clearer than "STALL_EN" now that there are
several different kinds of stalls.  Also, "INSTRUCTION_CACHE_INVALIDATE"
is a lot easier to understand at a glance than the terse "IS_FLUSH."
Signed-off-by: NKenneth Graunke <kenneth@whitecape.org>
[danvet: use INVALIDATE for ro cache flags for more consistency]
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NKeith Packard <keithp@keithp.com>

Not all PIPE_CONTROLs have a length of 2, so remove it from the #define
and make each invocation specify the desired length.
Signed-off-by: NKenneth Graunke <kenneth@whitecape.org>
[danvet: implement style suggestion from Ben Widawsdy]
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NKeith Packard <keithp@keithp.com>

While I think the previous code is correct, it was hard to follow and
hard to debug. Since we already have a ring abstraction, might as well
use it to handle the semaphore updates and compares.

I don't expect this code to make semaphores better or worse, but you
never know...

v2:
Remove magic per Keith's suggestions.
Ran Daniel's gem_ring_sync_loop test on this.

v3:
Ignored one of Keith's suggestions.

v4:
Removed some bloat per Daniel's recommendation.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NKeith 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: NAkshay Joshi <me@akshayjoshi.com>
Signed-off-by: NKeith Packard <keithp@keithp.com>

Prior to Ivybridge, the GFX_MODE would default to 0x800, meaning that
MI_FLUSH would flush the TLBs in addition to the rest of the caches
indicated in the MI_FLUSH command.  However starting with Ivybridge, the
register defaults to 0x2800 out of reset, meaning that to invalidate the
TLB we need to use PIPE_CONTROL.  Since we're not doing that yet, go
back to the old default so things work.

v2: don't forget to actually *clear* the new bit
Reviewed-by: NEric Anholt <eric@anholt.net>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: NKenneth Graunke <kenneth@whitecape.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Physically-addressed hardware status pages are initialized early in
the driver load process by i915_init_phys_hws. For UMS environments,
the ring structure is not initialized until the X server starts. At
that point, the entire ring structure is re-initialized with all new
values. Any values set in the ring structure (including
ring->status_page.page_addr) will be lost when the ring is
re-initialized.

This patch moves the initialization of the status_page.page_addr value
to intel_render_ring_init_dri.
Signed-off-by: NKeith Packard <keithp@keithp.com>
Cc: stable@kernel.org

[anholt v2: Don't forget that when going from cached to uncached, we
haven't been tracking the write domain from the CPU perspective, since
we haven't needed it for GPU coherency.]

[ickle v3: We also need to make sure we relinquish any fences on older
chipsets and clear the GTT for sane domain tracking.]
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NEric Anholt <eric@anholt.net>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>