The RPS register writing routines use the current value of min/max to
set certain limits and interrupt gating. If we set those afterwards, we
risk setting up the hw incorrectly and losing power management events,
and worse, trigger some internal assertions.
Reorder the calling sequences to be correct, and remove the then
unrequired clamping from inside set_rps(). And for a bonus, fix the bug
of calling gen6_set_rps() from Valleyview.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
v2: Fixed the botched locking on init_hw failure in i915_reset (Ville)
Call cleanup_ringbuffer on failed context create in init_hw (Ville)
v3: Add dev argument ti clean_ringbuffer
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We'll be looking at more than just mem_freq from dev_priv, so
just pass the whole thing.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Enabling rps (turbo setup) was put in a work queue because it may
take quite awhile. This change flushes the work queue to initialize
rps values before use by sysfs or debugfs. Specifically,
rps.delayed_resume_work is flushed before using rps.hw_max,
rps.max_delay, rps.min_delay, or rps.cur_delay.
This change fixes a problem in sysfs where show functions using
uninitialized values show incorrect values and store functions
using uninitialized values in range checks incorrectly fail to
store valid input values. This change also addresses similar use
before initialized problems in debugfs.
Signed-off-by: Tom O'Rourke <Tom.O'Rourke@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We need to use the clock control reg to figure out how many CZ clks are in
30ns and use that as the basis for our RC6 residency calculations.
v2: use ULL everywhere for consistency (Chris)
factor out bias for clarity (Chris)
References: https://bugs.freedesktop.org/show_bug.cgi?id=69692
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The lower layers of sysfs will not allow an "offset" of more than
GEN7_L3LOG_SIZE and also l3_access_valid() caps it a second time. But
it's a little easier to audit if we don't have to worry that the
subtraction will result in negative values.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Byt doesn't have rc6p and rc6pp support and even more important the
the offsets of the residency registers there's something else. So Just
return a constant 0 to avoid upsetting userspace tools like powertop.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Explain a bit in the commit message what's going on.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We'd only ever used this define to denote whether or not we have the
dynamic parity feature (DPF) and never to determine whether or not L3
exists. Baytrail is a good example of where L3 exists, and not DPF.
This patch provides clarify in the code for future use cases which might
want to actually query whether or not L3 exists.
v2: Add /* DPF == dynamic parity feature */
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On both Ivybridge and Haswell, row remapping information is saved and
restored with context. This means, we never actually properly supported
the l3 remapping because our sysfs interface is asynchronous (and not
tied to any context), and the known faulty HW would be reused by the
next context to run.
Not that due to the asynchronous nature of the sysfs entry, there is no
point modifying the registers for the existing context. Instead we set a
flag for all contexts to load the correct remapping information on the
next run. Interested clients can use debugfs to determine whether or not
the row has been remapped.
One could propose at this point that we just do the remapping in the
kernel. I guess since we have to maintain the sysfs interface anyway,
I'm not sure how useful it is, and I do like keeping the policy in
userspace; (it wasn't my original decision to make the
interface the way it is, so I'm not attached).
v2: Force a context switch when we have a remap on the next switch.
(Ville)
Don't let userspace use the interface with disabled contexts.
v3: Don't force a context switch, just let it nop
Improper context slice remap initialization, 1<<1 instead of 1<<i, but I
rewrote it to avoid a second round of confusion.
Error print moved to error path (All Ville)
Added a comment on why the slice remap initialization happens.
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Using LRI for setting the remapping registers allows us to stream l3
remapping information. This is necessary to handle per context remaps as
we'll see implemented in an upcoming patch.
Using the ring also means we don't need to frob the DOP clock gating
bits.
v2: Add comment about lack of worry for concurrent register access
(Daniel)
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Bikeshed the comment a bit by doing a s/XXX/Note - there's
nothing to fix.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Certain HSW SKUs have a second bank of L3. This L3 remapping has a
separate register set, and interrupt from the first "slice". A slice is
simply a term to define some subset of the GPU's l3 cache. This patch
implements both the interrupt handler, and ability to communicate with
userspace about this second slice.
v2: Remove redundant check about non-existent slice.
Change warning about interrupts of unknown slices to WARN_ON_ONCE
Handle the case where we get 2 slice interrupts concurrently, and switch
the tracking of interrupts to be non-destructive (all Ville)
Don't enable/mask the second slice parity interrupt for ivb/vlv (even
though all docs I can find claim it's rsvd) (Ville + Bryan)
Keep BYT excluded from L3 parity
v3: Fix the slice = ffs to be decremented by one (found by Ville). When
I initially did my testing on the series, I was using 1-based slice
counting, so this code was correct. Not sure why my simpler tests that
I've been running since then didn't pick it up sooner.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Haswell changed the log registers to be WO, so we can no longer read
them to determine the programming (which sucks, see later note). For
now, simply use the cached value, and hope HW doesn't screw us over.
v2: Simplify the logic to avoid an extra !, remove last, and fix the
buffer offset which broke along the rebase (Ville)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=57441
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The buf pointer used during l3_write is just char *, therefore it does
not require the silly any addition of offset.
v2: Also fix i915_l3_read with a suggested logic from Ville
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We always read a register for l3 parity reads, and we don't really want
to ever let userspace trick us into giving back less than the dword.
Writes are okay because we assume everything will be 0 filled, and as
such, if a user really wants to write less than a dword, let them.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Valleyview has its own render power state implementation with different
capability knobs - it has no RP0,RP1,RPn but rather RPe.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67734
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: kobe.qin@intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As getting error state doesn't anymore require big kmallocs,
make error state accessible also from sysfs.
v2: - error state clearing (Chris Wilson)
- user hint, proper access mode bits and name (Daniel Vetter)
v3: release resources in proper order (Chris Wilson)
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Apply Chris' s/error_state/error/ bikeshed on the sysfs
name. Also update the dmesg message, spotted by Chris.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We never check the return values, and there's not much we could do on
errors anyway. Just simplify the signatures. No functional changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Rename all VLV IOSF sideband register accessor functions to
vlv_<port>_{read,write}. No functional changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Instead of returning the cached value, which is just what the kernel
requested.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Uses slightly different interfaces than other platforms.
v2: track actual set freq, not requested (Rohit)
fix debug prints in init code (Jesse)
v3: don't write sleep reg (Jesse)
re-add RC6 wake limit write (Ben)
fixup thresholds to match other platforms (Ben)
clean up mem freq calculation (Ben)
clean up debug prints (Ben)
v4: move defines from punit patch (Ville)
v5: remove writes to nonexistent regs (Jesse)
put RP and RC regs together (Jesse)
fix RC6 enable (Jesse)
v6: use correct fuse reads from NC (Jesse)
split out min/max funcs for use in sysfs (Jesse)
add debugfs & sysfs freq controls (Jesse)
v7: update with Ben's hw_max changes (Jesse)
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net> (v6)
[danvet: Follow checkpatch sugggestion to use min_t to avoid casting
fun.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
commit 4f9b2fe0441d4bdf5666a306156b5d6755de2584
Author: Ben Widawsky <ben@bwidawsk.net>
Date: Fri Apr 5 14:29:22 2013 -0700
drm/i915: Better overclock support
changed the sysfs read semantics for 'gt_max_freq_mhz'. By
always returning overclock max instead of stored value.
Fix this by returning the stored value. Separate sysfs entry
should be considered for overclocking max freq.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=63415
Cc: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Most importantly this will allow users to set overclock frequencies in
sysfs. Previously the max was limited by the RP0 max as opposed to the
overclock max. This is useful if one wants to either limit the max
overclock frequency, or set the minimum frequency to be in the overclock
range. It also fixes an issue where if one sets the max frequency to be
below the overclock max, they wouldn't be able to set back the proper
overclock max.
In addition I've added a couple of other bits:
Show the overclock freq. as max in sysfs
Print the overclock max in debugfs.
Print a warning if the user sets the min frequency to be in the
overclock range.
In this patch I've decided to store the hw_max when we read it from the
pcode at init. The reason I do this is the pcode reads can fail, and are
slow.
v2: Report when user requested overclocked max (Daniel)
Remove when user sets min to overclock range (Daniel)
Reported-by: freezer from #intel-gfx on irc
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
[danvet: Fixup the s/100MHz/50MHz/ confusion in an unrelated comment
that Mika spotted.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It is customary to end sysfs attributes with a newline.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When l3 parity support for Haswell was enabled in
commit f27b92651d
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date: Tue Jul 24 20:47:32 2012 -0700
drm/i915: Expand DPF support to Haswell
no one noticed that the patch which introduced this macro
commit e1ef7cc299
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date: Tue Jul 24 20:47:31 2012 -0700
drm/i915: Macro to determine DPF support
missed one spot. Fix this.
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=57441
Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This allows the power related code to run independently of the rest of
the pipeline, extending the resume and init time improvements into
userspace, which would otherwise have been blocked on the struct mutex
if we were doing PCU communication.
v2: Also convert the locking for the rps sysfs interface.
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pretty astonishing how far apart these two members landed ... Especially since
I've already removed almost 200 lines in between.
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Somehow this hunk got dropped from my last patch. We do not have the
rc6_attrs when there is no CONFIG_PM so this causes a compilation error.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This is useful for userspace utilities which wish to use the previous
interface, specifically for micromanaging the increase/decrease steps by
setting min == max.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Provide a standardized sysfs interface for setting min, and max
frequencies. The code which reads the limits were lifted from the
debugfs files. As a brief explanation, the limits are similar to the CPU
p-states. We have 3 states:
RP0 - ie. max frequency
RP1 - ie. "preferred min" frequency
RPn - seriously lowest frequency
Initially Daniel asked me to clamp the writes to supported values, but
in conforming to the way the cpufreq drivers seem to work, instead
return -EINVAL (noticed by Jesse in discussion).
The values can be used by userspace wishing to control the limits of the
GPU (see the CC list for people who care).
v4: Make exceeding the soft limits return -EINVAL as well (Daniel)
v3: bug fix (Ben) - was passing the MHz value to gen6_set_rps instead of
the step value. To fix, deal only with step values by doing the divide
at the top.
v2: add the dropped mutex_unlock in error cases (Chris)
EINVAL on both too min, or too max (Daniel)
v2 Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
CC: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Userspace applications such as PowerTOP are interesting in being able to
read the current GPU frequency. The patch itself sets up a generic array
for gen6 attributes so we can easily add other items in the future (and
it also happens to be just about the cleanest way to do this).
The patch is a nice addition to
commit 1ac02185dff3afac146d745ba220dc6672d1d162
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Aug 30 13:26:48 2012 +0200
drm/i915: add a tracepoint for gpu frequency changes
Reading the GPU frequncy can be done by reading a file like:
/sys/class/drm/card0/render_frequency_mhz
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Name variables a bit better for copy-pasters. This got turned up as part
of review for upcoming sysfs patches.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The original patch was actually incorrect in stubbing out the sysfs for
l3 parity.
commit 5ab3633d69
Author: Hunt Xu <mhuntxu@gmail.com>
Date: Sun Jul 1 03:45:07 2012 +0000
drm/i915: make rc6 in sysfs functions conditional
Unfortunately Hunt didn't respond to my review comments, and Daniel
sucked in the patch again ignoring. Worst of all, I'm too lazy to write
the patch for what I originally wanted, which was to keep rc6 sysfs even
without CONFIG_PM. This simpler patch does enough to enable us to add
more sysfs entries though.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v3.6-rc2' into drm-intel-next
Backmerge Linux 3.6-rc2 to resolve a few funny conflicts before we put
even more madness on top:
- drivers/gpu/drm/i915/i915_irq.c: Just a spurious WARN removed in
-fixes, that has been changed in a variable-rename in -next, too.
- drivers/gpu/drm/i915/intel_ringbuffer.c: -next remove scratch_addr
(since all their users have been extracted in another fucntion),
-fixes added another user for a hw workaroudn.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Commit 0136db586c merges rc6 information
into the power group. However, when compiled with CONFIG_PM not set,
modprobing i915 would taint since power_group_name is defined as NULL.
This patch makes these rc6 in sysfs functions conditional upon the
definition of the CONFIG_PM macro to avoid the above-mentioned problem.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45181
Cc: stable@vger.kernel.org
Tested-by: Kris Karas <bugs-a12@moonlit-rail.com>
Signed-off-by: Hunt Xu <mhuntxu@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Originally I had a macro specifically for DPF support, and Daniel, with
good reason asked me to change it to this. It's not the way I would have
gone (and indeed I didn't), but for now there is no distinction as all
platforms with L3 also have DPF.
Note: The good reasons are that dpf is a l3$ feature (at least on
currrent hw), hence I don't expect one to go without the other.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: added note]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Positively checking for the required feature/gen is simpler than build
a cascade of negative "we need to bail" checks. And the later won't
scale if we add more stuff that doesn't fit in nicely.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Dumb binary interfaces which allow root-only updates of the cache
remapping registers. As mentioned in a previous patch, software using
this interface needs to know about HW limits, and other programming
considerations as the kernel interface does no checking for these things
on the root-only interface.
v1: Drop extra posting reads (Chris)
Return negative values in the sysfs interfaces on errors (Chris)
v2: Return -EINVAL for offset % 4 (Jesse)
Move schizo userspace check out (Jesse)
Cleaner sysfs item initializers (Daniel)
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Chris' fix for my 32b breakage was incorrect. do_div returns a
remainder. Go back to a divide macro which is more 32b friendly.
Tested on x86-64.
This has only been compile tested on 32b systems.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=48756
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Sincere-apologies: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
[danvet: fixup 32bit compile-fail.]
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Merge rc6 information into the power group for our device. Until now the
i915 driver has not had any sysfs entries (aside from the connector
stuff enabled by drm core). Since it seems like we're likely to have
more in the future I created a new file for sysfs stubs, as well as the
rc6 sysfs functions which don't really belong elsewhere (perhaps
i915_suspend, but most of the stuff is in intel_display,c).
displays rc6 modes enabled (as a hex mask):
cat /sys/class/drm/card0/power/rc6_enable
displays #ms GPU has been in rc6 since boot:
cat /sys/class/drm/card0/power/rc6_residency_ms
displays #ms GPU has been in deep rc6 since boot:
cat /sys/class/drm/card0/power/rc6p_residency_ms
displays #ms GPU has been in deepest rc6 since boot:
cat /sys/class/drm/card0/power/rc6pp_residency_ms
Important note: I've seen on SNB that even when RC6 is *not* enabled the
rc6 register seems to have a random value in it. I can only guess at the
reason reason for this. Those writing tools that utilize this value need
to be careful and probably want to scrutinize the value very carefully.
v2: use common rc6 residency units to milliseconds for the other RC6 types
v3: don't create sysfs files for GEN <= 5
add a rc6_enable to show a mask of enabled rc6 types
use unmerge instead of remove for sysfs group
squash intel_enable_rc6() extraction into this patch
v4: rename sysfs files (Chris)
CC: Chris Wilson <chris@chris-wilson.co.uk>
CC: Daniel Vetter <daniel.vetter@ffwll.ch>f
CC: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: squash in the 64bit division fix by Chris Wilson.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
