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path: root/drivers/gpu/drm/i915/intel_pm.c
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2016-01-07drm/i915: Add two-stage ILK-style watermark programming (v10)Matt Roper
In addition to calculating final watermarks, let's also pre-calculate a set of intermediate watermark values at atomic check time. These intermediate watermarks are a combination of the watermarks for the old state and the new state; they should satisfy the requirements of both states which means they can be programmed immediately when we commit the atomic state (without waiting for a vblank). Once the vblank does happen, we can then re-program watermarks to the more optimal final value. v2: Significant rebasing/rewriting. v3: - Move 'need_postvbl_update' flag to CRTC state (Daniel) - Don't forget to check intermediate watermark values for validity (Maarten) - Don't due async watermark optimization; just do it at the end of the atomic transaction, after waiting for vblanks. We do want it to be async eventually, but adding that now will cause more trouble for Maarten's in-progress work. (Maarten) - Don't allocate space in crtc_state for intermediate watermarks on platforms that don't need it (gen9+). - Move WaCxSRDisabledForSpriteScaling:ivb into intel_begin_crtc_commit now that ilk_update_wm is gone. v4: - Add a wm_mutex to cover updates to intel_crtc->active and the need_postvbl_update flag. Since we don't have async yet it isn't terribly important yet, but might as well add it now. - Change interface to program watermarks. Platforms will now expose .initial_watermarks() and .optimize_watermarks() functions to do watermark programming. These should lock wm_mutex, copy the appropriate state values into intel_crtc->active, and then call the internal program watermarks function. v5: - Skip intermediate watermark calculation/check during initial hardware readout since we don't trust the existing HW values (and don't have valid values of our own yet). - Don't try to call .optimize_watermarks() on platforms that don't have atomic watermarks yet. (Maarten) v6: - Rebase v7: - Further rebase v8: - A few minor indentation and line length fixes v9: - Yet another rebase since Maarten's patches reworked a bunch of the code (wm_pre, wm_post, etc.) that this was previously based on. v10: - Move wm_mutex to dev_priv to protect against racing commits against disjoint CRTC sets. (Maarten) - Drop unnecessary clearing of cstate->wm.need_postvbl_update (Maarten) Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1452108870-24204-1-git-send-email-matthew.d.roper@intel.com Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2016-01-06drm/i915: Sanitize watermarks after hardware state readout (v4)Matt Roper
Although we can do a good job of reading out hardware state, the graphics firmware may have programmed the watermarks in a creative way that doesn't match how i915 would have chosen to program them. We shouldn't trust the firmware's watermark programming, but should rather re-calculate how we think WM's should be programmed and then shove those values into the hardware. We can do this pretty easily by creating a dummy top-level state, running it through the check process to calculate all the values, and then just programming the watermarks for each CRTC. v2: Move watermark sanitization after our BIOS fb reconstruction; the watermark calculations that we do here need to look at pstate->fb, which isn't setup yet in intel_modeset_setup_hw_state(), even though we have an enabled & visible plane. v3: - Don't move 'active = optimal' watermark assignment; we just undo that change in the next patch anyway. (Ville) - Move atomic helper locking fix to separate patch. (Maarten) v4: - Grab connection_mutex before calling atomic helper to duplicate state. The connector loop inside the helper will throw a WARN if we don't hold something to protect the connector list (and the helper itself doesn't try to lock the list). - Make failure to calculate watermarks for inherited state a WARN() since it probably indicates a serious problem in either our state readout code or our watermark code for this platform. Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2016-01-06drm/i915: Add extra paranoia to ILK watermark calculationsMatt Roper
Our low-level watermark calculation functions don't get called when the CRTC is disabled or the relevant plane is invisible, so they should never see a zero htotal or zero bpp. However add some checks to ensure this is true so that we don't wind up dividing by zero if we make a mistake elsewhere in the driver (which the atomic watermark series has revealed we might be). References: http://lists.freedesktop.org/archives/intel-gfx/2015-October/077370.html Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1449171462-30763-6-git-send-email-matthew.d.roper@intel.com Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2016-01-06drm/i915: Convert hsw_compute_linetime_wm to use in-flight stateMatt Roper
When watermark calculation was moved up to the atomic check phase, the code was updated to calculate based on in-flight atomic state rather than already-committed state. However the hsw_compute_linetime_wm() didn't get updated and continued to pull values out of the currently-committed CRTC state. On platforms that call this function (HSW/BDW only), this will cause problems when we go to enable the CRTC since we'll pull the current mode (off) rather than the mode we're calculating for and wind up with a divide by zero error. This was an oversight in commit: commit a28170f3389f4e42db95e595b0d86384a79de696 Author: Matt Roper <matthew.d.roper@intel.com> Date: Thu Sep 24 15:53:16 2015 -0700 drm/i915: Calculate ILK-style watermarks during atomic check (v3) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1449171462-30763-5-git-send-email-matthew.d.roper@intel.com Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2015-12-18drm/i915: Apply broader WaRsDisableCoarsePowerGating for guc alsoMika Kuoppala
commit 344df9809f45 ("drm/i915/skl: Disable coarse power gating up until F0") failed to take into account that the same workaround is used in guc when forcewake is sampled. Wrap the condition check inside a macro and use it in both places to fix the guc side scope. Cc: Dave Gordon <david.s.gordon@intel.com> Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com> Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1450286318-6854-1-git-send-email-mika.kuoppala@intel.com
2015-12-17drm/i915: add support for checking RPM atomic sectionsImre Deak
In some cases we want to check whether we hold an RPM wakelock reference for the whole duration of a sequence. To achieve this add a new RPM atomic sequence counter that we increment any time the wakelock refcount drops to zero. Check whether the sequence number stays the same during the atomic section and that we hold the wakelock at the beginning of the section. Motivated by Chris. v2-v3: - unchanged v4: - swap the order of atomic_read() and assert_rpm_wakelock_held() in assert_rpm_atomic_begin() to avoid race Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v3) Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-10-git-send-email-imre.deak@intel.com
2015-12-17drm/i915: add support for checking if we hold an RPM referenceImre Deak
Atm, we assert that the device is not suspended until the point when the device is truly put to a suspended state. This is fine, but we can catch more problems if we check that RPM refcount is non-zero. After that one drops to zero we shouldn't access the device any more, even if the actual device suspend may be delayed. Change assert_rpm_wakelock_held() accordingly to check for a non-zero RPM refcount in addition to the current device-not-suspended check. For the new asserts to work we need to annotate every place explicitly in the code where we expect that the device is powered. The places where we only assume this, but may not hold an RPM reference: - driver load We assume the device to be powered until we enable RPM. Make this explicit by taking an RPM reference around the load function. - system and runtime sudpend/resume handlers These handlers are called when the RPM reference becomes 0 and know the exact point after which the device can get powered off. Disable the RPM-reference-held check for their duration. - the IRQ, hangcheck and RPS work handlers These handlers are flushed in the system/runtime suspend handler before the device is powered off, so it's guaranteed that they won't run while the device is powered off even though they don't hold any RPM reference. Disable the RPM-reference-held check for their duration. In all these cases we still check that the device is not suspended. These explicit annotations also have the positive side effect of documenting our assumptions better. This caught additional WARNs from the atomic modeset path, those should be fixed separately. v2: - remove the redundant HAS_RUNTIME_PM check (moved to patch 1) (Ville) v3: - use a new dedicated RPM wakelock refcount to also catch cases where our own RPM get/put functions were not called (Chris) - assert also that the new RPM wakelock refcount is 0 in the RPM suspend handler (Chris) - change the assert error message to be more meaningful (Chris) - prevent false assert errors and check that the RPM wakelock is 0 in the RPM resume handler too - prevent false assert errors in the hangcheck work too - add a device not suspended assert check to the hangcheck work v4: - rename disable/enable_rpm_asserts to disable/enable_rpm_wakeref_asserts and wakelock_count to wakeref_count - disable the wakeref asserts in the IRQ handlers and RPS work too - update/clarify commit message v5: - mark places we plan to change to use proper RPM refcounting with separate DISABLE/ENABLE_RPM_WAKEREF_ASSERTS aliases (Chris) 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/1450227139-13471-1-git-send-email-imre.deak@intel.com
2015-12-17drm/i915: refactor RPM disabling due to RC6 being disabledImre Deak
We can make the RPM dependency on RC6 explcit in the code by taking an actual RPM reference, instead of avoiding to drop the initial one. This will also enable us to remove the HAS_RUNTIME_PM special casing from more places in the next patch. v2: - fixed typo in commit message (Joonas) Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-4-git-send-email-imre.deak@intel.com
2015-12-16drm/i915: prefer for_each_intel_* macros for iterationJani Nikula
Use the for_each_intel_* macros for iterating intel_encoder, intel_connector, and intel_crtc. No functional changes. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1450262896-5325-1-git-send-email-jani.nikula@intel.com
2015-12-10drm/i915: Separate cherryview from valleyviewWayne Boyer
The cherryview device shares many characteristics with the valleyview device. When support was added to the driver for cherryview, the corresponding device info structure included .is_valleyview = 1. This is not correct and leads to some confusion. This patch changes .is_valleyview to .is_cherryview in the cherryview device info structure and simplifies the IS_CHERRYVIEW macro. Then where appropriate, instances of IS_VALLEYVIEW are replaced with IS_VALLEYVIEW || IS_CHERRYVIEW or equivalent. v2: Use IS_VALLEYVIEW || IS_CHERRYVIEW instead of defining a new macro. Also add followup patches to fix issues discovered during the first review. (Ville) v3: Fix some style issues and one gen check. Remove CRT related changes as CRT is not supported on CHV. (Imre, Ville) v4: Make a few more optimizations. (Ville) Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Signed-off-by: Wayne Boyer <wayne.boyer@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1449692975-14803-1-git-send-email-wayne.boyer@intel.com Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Acked-by: Jani Nikula <jani.nikula@intel.com>
2015-12-08drm/i915: vlv: clamp minimum RPS frequency to what Punit allowsImre Deak
As described in the code comment, I couldn't set the minimum RPS frequency on my BYT-M B0 to the minimum allowed as reported by Punit. Fix this by clamping the minimum value to the first one that was accepted on my machine. Atm this issue doesn't cause any test failures, since in igt/pm_rps we only check the cached version of the current frequency which is the same what has been set. In the future we'll add checks for the actual frequency too, and for that to pass this fix is necessary. Signed-off-by: Imre Deak <imre.deak@intel.com> Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1417711175-13271-1-git-send-email-imre.deak@intel.com
2015-12-08drm/i915/skl: Double RC6 WRL always onMika Kuoppala
WaRsDoubleRc6WrlWithCoarsePowerGating should be enabled for all Skylakes. Make it so. Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1449505785-20812-2-git-send-email-mika.kuoppala@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-12-08drm/i915/skl: Disable coarse power gating up until F0Mika Kuoppala
There is conflicting info between E0 and F0 steppings for this workarounds. Trust more authoritative source and be conservative and extend also for F0. This prevents numerous (>50) gpu hangs with SKL GT4e during piglit run. References: HSD: gen9lp/2134184 Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1449505785-20812-1-git-send-email-mika.kuoppala@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-12-03drm/i915: introduce is_active/activate/deactivate to the FBC terminologyPaulo Zanoni
The long term goal is to have enable/disable as the higher level functions and activate/deactivate as the lower level functions, just like we do for PSR and for the CRTC. This way, we'll run enable and disable once per modeset, while update, activate and deactivate will be run many times. With this, we can move the checks and code that need to run only once per modeset to enable(), making the code simpler and possibly a little faster. This patch is just the first step on the conversion: it starts by converting the current low level functions from enable/disable to activate/deactivate. This patch by itself has no benefits other than making review and rebase easier. Please see the next patches for more details on the conversion. v2: - Rebase. - Improve commit message (Chris). v3: Rebase after changing the patch order. Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/
2015-12-02drm/i915/bxt: backlight clock gating workaroundImre Deak
Per bspec, "Backlight PWM may stop in the asserted state, causing backlight to stay fully on. WA: Before disabling PWM, set CLKGATE_DIS_0 0x46530 bit 13 PWM1 Gating Dis (for PWM1) or bit 14 PWM2 Gating Dis (for PWM2). The bits can remain set without harm." (There's no workaround name for this.) This fixes some Broxton backlight issues. Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> [Jani: cleanup & commit message] Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1448958232-26520-3-git-send-email-jani.nikula@intel.com
2015-11-23Merge tag 'v4.4-rc2' into drm-intel-next-queuedDaniel Vetter
Linux 4.4-rc2 Backmerge to get at commit 1b0e3a049efe471c399674fd954500ce97438d30 Author: Imre Deak <imre.deak@intel.com> Date: Thu Nov 5 23:04:11 2015 +0200 drm/i915/skl: disable display side power well support for now so that we can proplery re-eanble skl power wells in -next. Conflicts are just adjacent lines changed, except for intel_fbdev.c where we need to interleave the changs. Nothing nefarious. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2015-11-18drm/i915: Type safe register read/writeVille Syrjälä
Make I915_READ and I915_WRITE more type safe by wrapping the register offset in a struct. This should eliminate most of the fumbles we've had with misplaced parens. This only takes care of normal mmio registers. We could extend the idea to other register types and define each with its own struct. That way you wouldn't be able to accidentally pass the wrong thing to a specific register access function. The gpio_reg setup is probably the ugliest thing left. But I figure I'd just leave it for now, and wait for some divine inspiration to strike before making it nice. As for the generated code, it's actually a bit better sometimes. Eg. looking at i915_irq_handler(), we can see the following change: lea 0x70024(%rdx,%rax,1),%r9d mov $0x1,%edx - movslq %r9d,%r9 - mov %r9,%rsi - mov %r9,-0x58(%rbp) - callq *0xd8(%rbx) + mov %r9d,%esi + mov %r9d,-0x48(%rbp) callq *0xd8(%rbx) So previously gcc thought the register offset might be signed and decided to sign extend it, just in case. The rest appears to be mostly just minor shuffling of instructions. v2: i915_mmio_reg_{offset,equal,valid}() helpers added s/_REG/_MMIO/ in the register defines mo more switch statements left to worry about ring_emit stuff got sorted in a prep patch cmd parser, lrc context and w/a batch buildup also in prep patch vgpu stuff cleaned up and moved to a prep patch all other unrelated changes split out v3: Rebased due to BXT DSI/BLC, MOCS, etc. v4: Rebased due to churn, s/i915_mmio_reg_t/i915_reg_t/ Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: http://patchwork.freedesktop.org/patch/msgid/1447853606-2751-1-git-send-email-ville.syrjala@linux.intel.com
2015-11-18drm/i915: Fix gpu frequency change tracingMika Kuoppala
With gen < 9 we have had always 50Mhz units as our hw ratio. With gen >= 9 the hw ratio changed to 16.667Mhz (50/3). The result was that our gpu frequency tracing started to output values 3 times larger than expected due to hardcoded scaling value. Fix this by using Use intel_gpu_freq() when generating Mhz value from ratio for 'intel_gpu_freq_change' trace event. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92591 Cc: stable@vger.kernel.org # v4.3+ Reported-by: Eero Tamminen <eero.t.tamminen@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1447776866-29384-1-git-send-email-mika.kuoppala@intel.com
2015-11-17drm/i915/skl: Correct other-pipe watermark update condition check (v2)Kumar, Mahesh
If ddb allocation for planes in current CRTC is changed, that doesn't lead to ddb allocation change for other CRTCs, because our DDB allocation is not dynamic according to plane parameters, ddb is allocated according to number of CRTC enabled, & divided equally among CTRC's. In current condition check during Watermark calculation, if number of plane/ddb allocation changes for current CRTC, Watermark for other pipes are recalculated. But there is no change in DDB allocation of other pipe so watermark is also not changed, This leads to warning messages. WARN_ON(!wm_changed) This patch corrects this and check if DDB allocation for pipes is changed, then only recalculate watermarks. v2 (by Matt): Rebased to latest -nightly and fixed a typo Signed-off-by: Kumar, Mahesh <mahesh1.kumar@intel.com> Reviewed-by(v1): Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-11-16drm/i915: Fix GT frequency roundingMika Kuoppala
When we set and later readback a frequency value through sysfs interface, igt/pm_rpm assumes that we get same value back if it matches hw granularity. On bxt we have found out that this is not always the case. Currently frequency - hw ratio - frequency conversions round down, with few exceptions on platforms that have more specific conversions. On bxt the supported range can be for example from 100Mhz to 650Mhz. Midpoint is then calculated by test to be 375 which pm_rps uses to find a closest hw supported frequency. That is 366 (ratio 22), which it then writes back. But as the rounding down kicks in, driver actually sets 350 instead of 366, as 366 is 2/3 below 22 * 50/3. Fix this by rounding to closest instead of rounding down in freq-ratio-freq conversions. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92768 Testcase: igt/pm_rps/basic-api Tested-by: Bob Paauwe <bob.j.paauwe@intel.com> Cc: Bob Paauwe <bob.j.paauwe@intel.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Bob Paauwe <bob.j.paauwe@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1447435781-23416-1-git-send-email-mika.kuoppala@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-11-02drm/i915/skl: Prevent unclaimed register writes on skylake.Maarten Lankhorst
I'm getting unclaimed register writes when checking the WM registers after the crtc is disabled. So I would imagine those are guarded by the crtc power well. Fix this by not reading out wm state when the power well is off. Cc: stable@vger.kernel.org # v4.3 Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92181 Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-29drm/i915: make A0 wa's applied to A1Tim Gore
Since A1 chips use the same GPU as A0, they need all the same wa's in the i915 driver. Update some conditionals to do this. Signed-off-by: Tim Gore <tim.gore@intel.com> Reviewed-by: Arun Siluvery <arun.siluvery@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1445856538-5417-1-git-send-email-tim.gore@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-28drm/i915/kbl: Introduce Kabylake platform defition.Rodrigo Vivi
Kabylake is a Intel® Processor containing Intel® HD Graphics following Skylake. It is Gen9p5, so it inherits everything from Skylake. Let's start by adding the platform separated from Skylake but reusing most of all features, functions etc. Later we rebase the PCI-ID patch without is_skylake=1 so we don't replace what original Author did there. Few IS_SKYLAKEs if statements are not being covered by this patch on purpose: - Workarounds: Kabylake is derivated from Skylake H0 so no W/As apply here. - GuC: A following patch removes Kabylake support with an explanation: No firmware available yet. - DMC/CSR: Done in a separated patch since we need to be carefull and load the version for revision 7 since Kabylake is Skylake H0. v2: relative cleaner commit message and added the missed IS_KABYLAKE to intel_i2c.c as pointed out by Jani. Cc: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-27drm/i915: Fix maxfifo watermark calc on vlv cursor planesThomas Daniel
A typo resulted in the watermarks for cursor planes not being calculated correctly. Fixed the typo. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Thomas Daniel <thomas.daniel@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-21drm/i915: Calculate watermark configuration during atomic check (v2)Matt Roper
v2: Don't forget to actually check the cstate->active value when tallying up the number of active CRTC's. (Ander) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com> Link: http://patchwork.freedesktop.org/patch/59561/
2015-10-21drm/i915: Calculate ILK-style watermarks during atomic check (v3)Matt Roper
Calculate pipe watermarks during atomic calculation phase, based on the contents of the atomic transaction's state structure. We still program the watermarks at the same time we did before, but the computation now happens much earlier. While this patch isn't too exciting by itself, it paves the way for future patches. The eventual goal (which will be realized in future patches in this series) is to calculate multiple sets up watermark values up front, and then program them at different times (pre- vs post-vblank) on the platforms that need a two-step watermark update. While we're at it, s/intel_compute_pipe_wm/ilk_compute_pipe_wm/ since this function only applies to ILK-style watermarks and we have a completely different function for SKL-style watermarks. Note that the original code had a memcmp() in ilk_update_wm() to avoid calling ilk_program_watermarks() if the watermarks hadn't changed. This memcmp vanishes here, which means we may do some unnecessary result generation and merging in cases where watermarks didn't change, but the lower-level function ilk_write_wm_values already makes sure that we don't actually try to program the watermark registers again. v2: Squash a few commits from the original series together; no longer leave pre-calculated wm's in a separate temporary structure since it's easier to follow the logic if we just cut over to using the pre-calculated values directly. v3: - Pass intel_crtc instead of drm_crtc to .compute_pipe_wm() entrypoint and use intel_atomic_get_crtc_state() to avoid need for extra casting. (Ander) - Drop unused intel_check_crtc() function prototype. (Ander) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com> Link: http://patchwork.freedesktop.org/patch/60363/
2015-10-21drm/i915: Calculate pipe watermarks into CRTC state (v3)Matt Roper
A future patch will calculate these during the atomic 'check' phase rather than at WM programming time, so let's store the watermark values we're planning to use in the CRTC state; the values actually active on the hardware remains in intel_crtc. While we're at it, do some minor restructuring to keep ILK and SKL values in a union. v2: Don't move cxsr_allowed to state (Maarten) v3: Only calculate watermarks in state. Still keep active watermarks in intel_crtc itself. (Ville) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com> Link: http://patchwork.freedesktop.org/patch/59556/
2015-10-21drm/i915: Refactor ilk_update_wm (v3)Ville Syrjälä
Split ilk_update_wm() into two parts; one doing the programming and the other the calculations. v2: Fix typo in commit message v3 (by Matt): Heavily rebased for current codebase. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com> Link: http://patchwork.freedesktop.org/patch/60366/
2015-10-21drm/i915: Drop intel_update_sprite_watermarksMatt Roper
The only platform that still has an update_sprite_wm entrypoint is SKL; on SKL, intel_update_sprite_watermarks just updates intel_plane->wm and then performs a regular watermark update. However intel_plane->wm is only used to update a couple fields in intel_wm_config, and those fields are never used by the SKL code, so on SKL an update_sprite_wm is effectively identical to an update_wm call. Since we're already ensuring that the regular intel_update_wm is called any time we'd try to call intel_update_sprite_watermarks, the whole call is redundant and can be dropped. Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com> Link: http://patchwork.freedesktop.org/patch/60372/
2015-10-21drm/i915/ivb: Move WaCxSRDisabledForSpriteScaling w/a to atomic checkMatt Roper
Determine whether we need to apply this workaround at atomic check time and just set a flag that will be used by the main watermark update routine. Moving this workaround into the atomic framework reduces ilk_update_sprite_wm() to just a standard watermark update, so drop it completely and just ensure that ilk_update_wm() is called whenever a sprite plane is updated in a way that would affect watermarks. Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com> Link: http://patchwork.freedesktop.org/patch/60367/
2015-10-21drm/i915: add helpers for platform specific revision id range checksJani Nikula
Revision checks are almost always accompanied by a platform check. (The exceptions are platform specific code.) Add helpers to check for a platform and a revision range: IS_SKL_REVID() and IS_BXT_REVID(). In most places this simplifies and clarifies the code. It will be obvious that revid macros are used for the correct platform. This should make it easier to find all the revision checks for workarounds for each platform, and make it easier to remove them once we drop support for early hardware revisions. This should also make it easier to differentiate between Skylake and Kabylake revision checks when Kabylake support is added. v2: rebase Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1445343722-3312-3-git-send-email-jani.nikula@intel.com
2015-10-21drm/i915/bxt: add revision id for A1 stepping and use itJani Nikula
Prefer inclusive ranges for revision checks rather than "below B0". Per specs A2 is not used, so revid <= A1 matches revid < B0. Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1445343722-3312-2-git-send-email-jani.nikula@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-10-19drm/i915/skl: Eliminate usage of pipe_wm_parameters from SKL-style WM (v4)Matt Roper
Just pull the info out of the state structures rather than staging it in an additional set of structures. To make this more straightforward, we change the signature of several internal WM functions to take the crtc state as a parameter. v2: - Don't forget to skip cursor planes on a loop in the DDB allocation function to match original behavior. (Ander) - Change a use of intel_crtc->active to cstate->active. They should be identical, but it's better to be consistent. (Ander) - Rework more function signatures to pass states rather than crtc for consistency. (Ander) v3: - Add missing "+ 1" to skl_wm_plane_id()'s 'overlay' case. (Maarten) - Packed formats should pass '0' to drm_format_plane_cpp(), not 1. (Maarten) - Drop unwanted WARN_ON() for disabled planes when calculating data rate for SKL. (Maarten) v4: - Don't include cursor plane in total relative data rate calculation; we've already handled the cursor allocation earlier. - Fix 'bytes_per_pixel' calculation braindamage. Somehow I hardcoded the NV12 format as a parameter rather than the actual fb->pixel_format, and even then still managed to get the format plane wrong. (Ville) - Use plane->state->fb rather than plane->fb in skl_allocate_pipe_ddb(); the plane->fb pointer isn't updated until after we've done our watermark recalculation, so it has stale values. (Bob Paauwe) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by(v3): Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Paauwe, Bob J <bob.j.paauwe@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Paulo Zanoni <paulo.r.zanoni@intel.com> References: http://lists.freedesktop.org/archives/intel-gfx/2015-September/077060.html References: http://lists.freedesktop.org/archives/intel-gfx/2015-October/077721.html Smoke-tested-by(v4): Paulo Zanoni <paulo.r.zanoni@intel.com> (SKL) Link: http://patchwork.freedesktop.org/patch/61968/
2015-10-13drm/i915: Move skl/bxt gt specific workarounds to ring initMika Kuoppala
Some registers are, naturally, lost in gpu reset/suspend cycle. And some registers, for example in display domain, are not subject to gpu reset so they retain their contents. As hang recovery triggers a reset, recoverable gpu hang can currently flush out essential workarounds and cause havoc later on. When register GEN8_GARBNTL is missing the WaEnableGapsTsvCreditFix:skl, it can cause random system hangs [1]. This workaround was added in: commit 245d96670d26 ("drm/i915:skl: Add WaEnableGapsTsvCreditFix") But another set of system hangs were observed and the failure pattern indicated that there was random gpu hang preceding the system hang [2]. This lead to the realization that we lose this workaround and BDW_SCRATCH1 on reset. Add these workarounds setup in display init to skl/bxt ring init where LRI workarounds are also setup. This way their setup is not dependent on display side init. References: [1] https://bugs.freedesktop.org/show_bug.cgi?id=90854 References: [2] https://bugs.freedesktop.org/show_bug.cgi?id=92315 Reported-by: Tomi Sarvela <tomix.p.sarvela@intel.com> Cc: Tomi Sarvela <tomix.p.sarvela@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Tested-by: Tomi Sarvela <tomix.p.sarvela@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-10-13drm/i915: revert a few more watermark commitsPaulo Zanoni
This is a squash of the following commits: Revert "drm/i915: Drop intel_update_sprite_watermarks" This reverts commit 47c99438b52d12df50e182583634a4cfede3c920. Revert "drm/i915/ivb: Move WaCxSRDisabledForSpriteScaling w/a to atomic check" This reverts commit 7809e5ae35b9d8d0710f0874b2e3f10be144e38b. Revert "drm/i915/skl: Eliminate usage of pipe_wm_parameters from SKL-style WM (v3)" This reverts commit 3a05f5e2e78eab7ffe816abb59b6769e331a1957. With these reverts, SKL finally stops failing every single FBC test with FIFO underrun error messages. After some brief testing, it also seems that this commit prevents the machine from completely freezing when we run igt/kms_fbc_crc (see fd.o #92355). Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92355 Cc: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-10-09drm/i915: Partial revert of atomic watermark seriesMatt Roper
It's been reported that the atomic watermark series triggers some regressions on SKL, which we haven't been able to track down yet. Let's temporarily revert these patches while we track down the root cause. This commit squashes the reverts of: 76305b1 drm/i915: Calculate watermark configuration during atomic check (v2) a4611e4 drm/i915: Don't set plane visible during HW readout if CRTC is off a28170f drm/i915: Calculate ILK-style watermarks during atomic check (v3) de4a9f8 drm/i915: Calculate pipe watermarks into CRTC state (v3) de165e0 drm/i915: Refactor ilk_update_wm (v3) Reference: http://lists.freedesktop.org/archives/intel-gfx/2015-October/077190.html Cc: "Zanoni, Paulo R" <paulo.r.zanoni@intel.com> Cc: "Vetter, Daniel" <daniel.vetter@intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-10-07drm/i915/chv: remove pre-production hardware workaroundsJani Nikula
Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> [danvet: Appease gcc and remove the unused variable.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-10-06drm/i915: Update Promotion timer for RC6 TO ModeSagar Arun Kamble
When using RC6 timeout mode, the timeout value should be written to GEN6_RC6_THRESHOLD. v2: Updated commit message. (Tom) v3: Rebase over whitespace differences. (Daniel) Cc: Tom O'Rourke <Tom.O'Rourke@intel.com> Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com> Reviewed-by: Tom O'Rourke <Tom.O'Rourke@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Calculate watermark configuration during atomic check (v2)Matt Roper
v2: Don't forget to actually check the cstate->active value when tallying up the number of active CRTC's. (Ander) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Calculate ILK-style watermarks during atomic check (v3)Matt Roper
Calculate pipe watermarks during atomic calculation phase, based on the contents of the atomic transaction's state structure. We still program the watermarks at the same time we did before, but the computation now happens much earlier. While this patch isn't too exciting by itself, it paves the way for future patches. The eventual goal (which will be realized in future patches in this series) is to calculate multiple sets up watermark values up front, and then program them at different times (pre- vs post-vblank) on the platforms that need a two-step watermark update. While we're at it, s/intel_compute_pipe_wm/ilk_compute_pipe_wm/ since this function only applies to ILK-style watermarks and we have a completely different function for SKL-style watermarks. Note that the original code had a memcmp() in ilk_update_wm() to avoid calling ilk_program_watermarks() if the watermarks hadn't changed. This memcmp vanishes here, which means we may do some unnecessary result generation and merging in cases where watermarks didn't change, but the lower-level function ilk_write_wm_values already makes sure that we don't actually try to program the watermark registers again. v2: Squash a few commits from the original series together; no longer leave pre-calculated wm's in a separate temporary structure since it's easier to follow the logic if we just cut over to using the pre-calculated values directly. v3: - Pass intel_crtc instead of drm_crtc to .compute_pipe_wm() entrypoint and use intel_atomic_get_crtc_state() to avoid need for extra casting. (Ander) - Drop unused intel_check_crtc() function prototype. (Ander) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Calculate pipe watermarks into CRTC state (v3)Matt Roper
A future patch will calculate these during the atomic 'check' phase rather than at WM programming time, so let's store the watermark values we're planning to use in the CRTC state; the values actually active on the hardware remains in intel_crtc. While we're at it, do some minor restructuring to keep ILK and SKL values in a union. v2: Don't move cxsr_allowed to state (Maarten) v3: Only calculate watermarks in state. Still keep active watermarks in intel_crtc itself. (Ville) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Refactor ilk_update_wm (v3)Ville Syrjälä
Split ilk_update_wm() into two parts; one doing the programming and the other the calculations. v2: Fix typo in commit message v3 (by Matt): Heavily rebased for current codebase. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Drop intel_update_sprite_watermarksMatt Roper
The only platform that still has an update_sprite_wm entrypoint is SKL; on SKL, intel_update_sprite_watermarks just updates intel_plane->wm and then performs a regular watermark update. However intel_plane->wm is only used to update a couple fields in intel_wm_config, and those fields are never used by the SKL code, so on SKL an update_sprite_wm is effectively identical to an update_wm call. Since we're already ensuring that the regular intel_update_wm is called any time we'd try to call intel_update_sprite_watermarks, the whole call is redundant and can be dropped. Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915/ivb: Move WaCxSRDisabledForSpriteScaling w/a to atomic checkMatt Roper
Determine whether we need to apply this workaround at atomic check time and just set a flag that will be used by the main watermark update routine. Moving this workaround into the atomic framework reduces ilk_update_sprite_wm() to just a standard watermark update, so drop it completely and just ensure that ilk_update_wm() is called whenever a sprite plane is updated in a way that would affect watermarks. Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915/skl: Eliminate usage of pipe_wm_parameters from SKL-style WM (v3)Matt Roper
Just pull the info out of the state structures rather than staging it in an additional set of structures. To make this more straightforward, we change the signature of several internal WM functions to take the crtc state as a parameter. v2: - Don't forget to skip cursor planes on a loop in the DDB allocation function to match original behavior. (Ander) - Change a use of intel_crtc->active to cstate->active. They should be identical, but it's better to be consistent. (Ander) - Rework more function signatures to pass states rather than crtc for consistency. (Ander) v3: - Add missing "+ 1" to skl_wm_plane_id()'s 'overlay' case. (Maarten) - Packed formats should pass '0' to drm_format_plane_cpp(), not 1. (Maarten) - Drop unwanted WARN_ON() for disabled planes when calculating data rate for SKL. (Maarten) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915/skl: Simplify wm structures slightly (v2)Matt Roper
A bunch of SKL watermark-related structures have the cursor plane as a separate entry from the rest of the planes. Since a previous patch updated I915_MAX_PLANES such that those plane arrays now have a slot for the cursor, update the code to use the new slot in the existing plane arrays and kill off the cursor-specific structures. There shouldn't be any functional change here; this is just shuffling around how the data is stored in some of the data structures. The whole patch is generated with Coccinelle via the following semantic patch: @@ struct skl_pipe_wm_parameters WMP; @@ - WMP.cursor + WMP.plane[PLANE_CURSOR] @@ struct skl_pipe_wm_parameters *WMP; @@ - WMP->cursor + WMP->plane[PLANE_CURSOR] @@ @@ struct skl_pipe_wm_parameters { ... - struct intel_plane_wm_parameters cursor; ... }; @@ struct skl_ddb_allocation DDB; expression E; @@ - DDB.cursor[E] + DDB.plane[E][PLANE_CURSOR] @@ struct skl_ddb_allocation *DDB; expression E; @@ - DDB->cursor[E] + DDB->plane[E][PLANE_CURSOR] @@ @@ struct skl_ddb_allocation { ... - struct skl_ddb_entry cursor[I915_MAX_PIPES]; ... }; @@ struct skl_wm_values WMV; expression E1, E2; @@ ( - WMV.cursor[E1][E2] + WMV.plane[E1][PLANE_CURSOR][E2] | - WMV.cursor_trans[E1] + WMV.plane_trans[E1][PLANE_CURSOR] ) @@ struct skl_wm_values *WMV; expression E1, E2; @@ ( - WMV->cursor[E1][E2] + WMV->plane[E1][PLANE_CURSOR][E2] | - WMV->cursor_trans[E1] + WMV->plane_trans[E1][PLANE_CURSOR] ) @@ @@ struct skl_wm_values { ... - uint32_t cursor[I915_MAX_PIPES][8]; ... - uint32_t cursor_trans[I915_MAX_PIPES]; ... }; @@ struct skl_wm_level WML; @@ ( - WML.cursor_en + WML.plane_en[PLANE_CURSOR] | - WML.cursor_res_b + WML.plane_res_b[PLANE_CURSOR] | - WML.cursor_res_l + WML.plane_res_l[PLANE_CURSOR] ) @@ struct skl_wm_level *WML; @@ ( - WML->cursor_en + WML->plane_en[PLANE_CURSOR] | - WML->cursor_res_b + WML->plane_res_b[PLANE_CURSOR] | - WML->cursor_res_l + WML->plane_res_l[PLANE_CURSOR] ) @@ @@ struct skl_wm_level { ... - bool cursor_en; ... - uint16_t cursor_res_b; - uint8_t cursor_res_l; ... }; v2: Use a PLANE_CURSOR enum entry rather than making the code reference I915_MAX_PLANES or I915_MAX_PLANES+1, which was confusing. (Ander) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Eliminate usage of pipe_wm_parameters from ILK-style WM (v2)Matt Roper
Just pull the info out of the CRTC state structure rather than staging it in an additional structure. Note that we use cstate->active rather than intel_crtc->active which may appear to be a change in behavior. However since we're no longer trying to recalculate watermarks during the "pipe off" stage of a modeset, intel_crtc->active and cstate->active should always be identical when watermarks are calculated (at least for ILK-style platforms). v2: Clarify reasoning for cstate->active and add a WARN_ON to the code to assert that it really is always identical to intel_crtc->active as expected. Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Eliminate usage of plane_wm_parameters from ILK-style WM code (v2)Matt Roper
Just pull the info out of the plane state structure rather than staging it in an additional structure. v2: Add 'visible' condition to sprites_scaled so that we don't limit the WM level when the sprite isn't enabled. (Ville) Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by(v1): Ander Conselvan de Oliveira <conselvan2@gmail.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: s/_TRANSA_CHICKEN/TRANS_CHICKEN(PIPE_A)/Ville Syrjälä
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-09-30drm/i915: Read czclk from CCK on vlv/chvVille Syrjälä
As with the cdclk, read out czclk from CCK as well. This gives us the real current value and avoids having to decode fuses and whatnot. Also store it in kHz under dev_priv like we do for cdlck since it's not just an rps related clock, and having it in kHz is more standard/convenient for some things. Imre also pointed out that we currently fail to read czclk on VLV, which means the PFI credit programming isn't working as expected. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>