Display WA #1183 was recently added to workaround
"Failures when enabling DPLL0 with eDP link rate 2.16
or 4.32 GHz and CD clock frequency 308.57 or 617.14 MHz
(CDCLK_CTL CD Frequency Select 10b or 11b) used in this
enabling or in previous enabling."
This workaround was designed to minimize the impact only
to save the bad case with that link rates. But HW engineers
indicated that it should be safe to apply broadly, although
they were expecting the DPLL0 link rate to be unchanged on
runtime.
We need to cover 2 cases: when we are in fact enabling DPLL0
and when we are just changing the frequency with small
differences.
This is based on previous patch by Rodrigo Vivi with suggestions
from Ville Syrjälä.
Cc: Arthur J Runyan <arthur.j.runyan@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171204232210.4958-1-lucas.demarchi@intel.com
Looking at a CI failure with an ominous line of
[ 362.550715] hangcheck current seqno ffffff6b, last ffffff8c, hangcheck ffffff6b [6016 ms], inflight 118
with no apparent cause for the seqno to be negative, left me wondering
if someone had scribbled over the HWSP. So include the HWSP in the
engine dump to see if there are more signs of random scribbling.
v2: Fix row pointer, i is now incremented by 8 so doesn't need scaling
by 8, and we don't need to keep volatile here as the status_page isn't
marked up as volatile itself.
v3: Use hexdump, with suppression of identical lines. (Tvrtko)
Which results in
HWSP:
00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
*
00000040 00000001 00000000 00000018 00000002 00000001 00000000 00000018 00000000
00000060 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000003
00000080 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
*
000000c0 00000002 00000000 00000000 00000000 00000000 00000000 00000000 00000000
000000e0 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
*
instead of 128 lines of mostly 0s.
v4: Tidy up the locals
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171222182521.18106-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
We should only attempt to remove requests from the execution queue that
are on the execution queue. These are the requests that have been
assigned a global_seqno, so we can assert that we only attempt to remove
requests with a nonzero global_seqno. Afterwards we assert that we
remove them in order, i.e. the global_seqno matches the engine's seqno,
but that leaves a small loophole for an unattached request on an unused
engine.
We can then make the same assertion on queuing the request to the
execution engine, it must have a zero global_seqno or else we are queuing
the same request twice.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171222141959.3006-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
We have plenty of global registers and whatnot programmed without
any further locking by the modeset code. Currently non-bocking
modesets are allowed to execute in parallel which could corrupt
said registers.
To avoid the problem let's run all non-blocking modesets on an
ordered workqueue. We still put page flips etc. to system_unbound_wq
allowing page flips on one pipe to execute in parallel with page flips
or a modeset on a another pipe (assuming no known state is shared
between them, at which point they would have been added to the same
atomic commit and serialized that way).
Blocking modesets are already serialized with each other by
connection_mutex, and thus are safe. To serialize them with
non-blocking modesets we just flush the workqueue before executing
blocking modesets.
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: 94f050246b ("drm/i915: nonblocking commit")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171113133622.8593-1-ville.syrjala@linux.intel.com
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Gen9+ need to disable GMBUS clock gating when doing multi part
transfers. Otherwise clock gating will kick in when GMBUS is in
the WAIT state and presumably that will corrupt the transfer.
This is documented as Display WA #0868.
Apparently older hardware doesn't allow clock gating in the WAIT
state and thus are unaffected by this problem.
v2: Limit the PCH w/a to gen9 and gen10 only (DK)
Actually change it to check the PCH type instead since
it's the PCH that actually contains the GMBUS hardware
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20171221202432.17373-1-ville.syrjala@linux.intel.com
Our QA reported a problem caused by movntdqa instructions. Currently,
the KVM hypervisor doesn't support VEX-prefix instructions emulation.
If users passthrough a GPU to guest with vfio option 'x-no-mmap=on',
then all access to the BARs will be trapped and emulated. The KVM
hypervisor would raise an inertal error to qemu which cause the guest
killed. (Since 'movntdqa' ins is not supported.)
This patch try not to enable movntdqa optimization if the driver is
running in hypervisor guest.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1513924309-3113-1-git-send-email-changbin.du@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
During initialization of the runtime part of the intel_device_info
we are dumping that part using DRM_DEBUG_DRIVER mechanism.
As we already have pretty printer for const part of the info,
make similar function for the runtime part and use it separately.
v2: add runtime dump to debugfs (Chris)
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171221185334.17396-7-michal.wajdeczko@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171221215735.30314-6-chris@chris-wilson.co.uk
We already have dedicated file for opregion related code, dedicated
header will make our life easier.
v2: reorder includes (Chris)
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171221185334.17396-4-michal.wajdeczko@intel.com
[ickle: quieten checkpatch]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171221215735.30314-3-chris@chris-wilson.co.uk
It's a bit confusing that page write protect handler is live in
mmio emulation handler. This moves it to stand alone gvt ops.
Also remove unnecessary check of write protected page access
in mmio read handler and cleanup handling of failsafe case.
v2: rebase
Reviewed-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We had previous hack that tried to accept either i915_reg_t or offset
value to access vGPU virtual/shadow regs which broke that purpose to
be type safe in context. This one trys to explicitly separate the usage
of typed mmio reg with real offset.
Old vgpu_vreg(offset) helper is used only for offset now with new
vgpu_vreg_t(reg) is used for i915_reg_t only. Convert left usage
of that to new helper.
Also fixed left KASAN warning issues caused by previous hack.
v2: rebase, fixup against recent mmio switch change
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
observed igt drv_module_reload test case failure on 4.15.0
rc2 kernel with panic due to no active pipe available.
the gpu will reset during unload/load and make pipe config reg
lost which can cause kernel panic issue happen.
this patch is to move pipe enabling to emulate_mointor_status_chagne
to handle vgpu reset case as well.
Fixes: 7e60590208 ("drm/i915/gvt: enabled pipe A default on creating vgpu")
Signed-off-by: Xiaolin Zhang <xiaolin.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
(cherry picked from commit f5f00e7dcc)
Always requires properly defined i915_reg_t type for MMIO handler
definition.
Fix kasan warning of "drivers/gpu/drm/i915/gvt/handlers.c:2397:1: error: the frame size of 32120 bytes is larger than 8192 bytes"
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We don't need any active planes during load detection, so just disable
them all. This saves us from having to come up with a suitable
framebuffer. And we also avoid leaving sprite/cursor planes on and
potentially presenting them at a peculiar location during the load
detection.
Changes since v1 (Maarten):
- Add missing call to add_all_affected_planes.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102707
Link: https://patchwork.freedesktop.org/patch/msgid/20171220093545.613-4-maarten.lankhorst@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Looking at the coordination of resets with the submission of execlists,
it will be useful to have a GEM_TRACE for when we issue the reset.
Whilst there tidy up the other GEM_TRACE to always include the engine
name, and be careful not to trust any pointers prior to asserts.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171220090626.31643-1-chris@chris-wilson.co.uk
Commit 77affa3172 ("drm/i915/psr: Fix compiler warnings for
hsw_psr_disable()") swapped status and control registers while fixing
indentation. The _ctl at the end of the status register name must have to
led to this.
Fixes: 77affa3172 ("drm/i915/psr: Fix compiler warnings for hsw_psr_disable()")
References: https://www.mrc-cbu.cam.ac.uk/people/matt.davis/cmabridge/
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171220043520.2599-1-dhinakaran.pandiyan@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Use the local on-stack struct directly rather than hide it behind a
pointer. This should be both clearer for the reader and the compiler (we
rely on the compiler seeing through the functions to spot uninitialized
uses of the local).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171219130948.6282-1-chris@chris-wilson.co.uk
There seems to be another clock gating issue which the workaround is
described as:
"WA: Set 0xE4F0[1] = 1 to disable Early EOT of thread."
Signed-off-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171216001117.14232-2-rafael.antognolli@intel.com
We dump modparams in few places (debugfs, gpu_error) using different
functions. Lets add reusable function to avoid code duplication.
add/remove: 1/0 grow/shrink: 0/2 up/down: 1096/-2339 (-1243)
Function old new delta
i915_params_dump - 1096 +1096
i915_capabilities 1353 185 -1168
i915_error_state_to_str 5507 4336 -1171
Total: Before=1285716, After=1284473, chg -0.10%
v2: use forward decl rather than include (Chris)
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171219114346.26308-3-michal.wajdeczko@intel.com
Convert intel_device_info_dump into pretty printer to be
consistent with the rest of the driver code.
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171219114346.26308-2-michal.wajdeczko@intel.com
We dump device flags in few places (init_early, debugfs, gpu_error)
using different functions. Lets add reusable function to avoid
code duplication.
add/remove: 1/0 grow/shrink: 0/3 up/down: 1296/-3572 (-2276)
Function old new delta
intel_device_info_dump_flags - 1296 +1296
i915_capabilities 2435 1353 -1082
i915_error_state_to_str 6642 5507 -1135
intel_device_info_dump 1507 152 -1355
Total: Before=1287992, After=1285716, chg -0.18%
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171219114346.26308-1-michal.wajdeczko@intel.com
drivers/gpu/drm/i915/intel_ddi.c:2098 intel_ddi_clk_select() warn: inconsistent indenting
References: 8edcda1266 ("drm/i915: Protect DDI port to DPLL map from theoretical race.")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171219112649.9388-1-chris@chris-wilson.co.uk
After a reset, the state of the CSB registers are scrubbed and not valid
until a powercontext is reloaded. We only know when a powercontext has
been reloaded once we see a CS-interrupt, before then we must ignore the
CSB registers within the execlists_submission_tasklet. However, glk is
sporadically dying with an illegal CSB pointer value (both in the HSWP
and mmio) suggesting that it is running with the CS-interrupt bit set
before the powercontext has been reloaded. Make sure the clearing of
that bit is serialised on reset with the re-enabling of the tasklet.
References: https://bugs.freedesktop.org/show_bug.cgi?id=104262
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171219090110.11153-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
In case we have multiple modesets for different connectors
happening in parallel we could have a race on the RMW on these
shared registers.
This possibility was initially raised by Paulo when reviewing
commit '555e38d27317 ("drm/i915/cnl: DDI - PLL mapping")'
but the original possibility comes from commit '5416d871136d
("drm/i915/skl: Set the eDP link rate on DPLL0")'. Or maybe
later when atomic commits entered into picture.
Apparently the discussion around this topic showed that the
right solution would be on serializing the atomic commits in
a way that we don't have the possibility of races here since
if that parallel modeset happenings apparently many other
things will be on fire.
Code is there since SKL and there was no report of issue,
but since we never looked back to that serialization possibility,
and also we don't have an igt case for that it is better to at
least protect this corner.
Suggested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Fixes: 555e38d273 ("drm/i915/cnl: DDI - PLL mapping")
Fixes: 5416d87113 ("drm/i915/skl: Set the eDP link rate on DPLL0")
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/20171215224310.19103-1-rodrigo.vivi@intel.com
Now that we skip a per-engine reset on an idle engine, we need to update
the selftest to take that into account. In the process, we find that we
were not stressing the per-engine reset very hard, so add those missing
active resets.
v2: Actually test i915_reset_engine() by loading it with requests.
Fixes: f6ba181ada ("drm/i915: Skip an engine reset if it recovered before our preparations")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104313
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171217132852.30642-3-chris@chris-wilson.co.uk
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
When monitoring the GPU with i915 perf, reports are tagged with a hw
id. Gem context creation tracepoints already have a hw_id field,
unfortunately you only get this correlation between a process id and a
hw context id once when the context is created. It doesn't help if you
started monitoring after the process was initialized or if the drm fd
was transfered from one process to another.
This change adds the hw_id field to gem requests, so that correlation
can also be done on submission.
v2: Place hw_id at the end of the tracepoint to not disrupt too much
existing tools (Chris)
v3: Reorder hw_id field again (Chris)
v4: Add missing hw_id to i915_gem_request_wait_begin tracepoint (Chris)
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171218151959.14073-3-lionel.g.landwerlin@intel.com
Let's make the order of the fields of the tracepoints involving gem
request match across i915. This makes userspace processing of
tracepoint a bit easier.
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171218151959.14073-2-lionel.g.landwerlin@intel.com
A useful bit of information for inspecting GPU stalls from
intel_engine_dump() are the error registers, IPEIR and IPEHR.
v2: Fixup gen changes in register offsets (Tvrtko)
v3: Old FADDR location as well
v4: Use I915_READ64_2x32
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171218123914.19027-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
We have an existing helper for testing obj->mm.pages, so use it.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171218103855.25274-1-matthew.auld@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Inside i915_gem_reset(), we start touching the HW and so require the
low-level HW to be re-enabled, in particular the PCI BARs.
Fixes: 7b6da818d8 ("drm/i915: Restore the kernel context after a GPU reset on an idle engine")
References: 0db8c96120 ("drm/i915: Re-enable GTT following a device reset")
Testcase: igt/drv_hangman #i915g/i915gm
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171217132852.30642-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Load host render mocs registers once for delta update of mocs switch, it
reduces mmio read times obviously, then brings performance improvement
during multi-vms switch.
Signed-off-by: Weinan Li <weinan.z.li@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Save and restore the mocs regs of one VM in GVT-g burning too much CPU
utilization. Add LRI command scan to monitor the change of mocs registers,
save the state in vreg, and use delta update policy to restore them.
It can obviously reduce the MMIO r/w count, and improve the performance
of context switch.
Signed-off-by: Weinan Li <weinan.z.li@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Now mmio switch between vGPUs need to switch to host first then to expected
vGPU, it waste one time mmio save/restore. r/w mmio usually is
time-consuming, and there are so many mocs registers need to save/restore
during vGPU switch. Combine the switch_to_host and switch_to_vgpu can
reduce 1 time mmio save/restore, it will reduce the CPU utilization and
performance while there is multi VMs with heavy work load.
Signed-off-by: Weinan Li <weinan.z.li@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Lucas De Marchi