Current vblank emulator uses single hrtimer at 16ms period for all vGPUs,
which introduces three major issues:
- 16ms matches the refresh rate at 62.5Hz (instead of 60Hz) which
doesn't follow standard timing. This leads to some frame drop or glitch
issue during video playback. SW expects a vsync interval of 16.667ms or
higher precision for an accurate 60Hz refresh rate. However current
vblank emulator only works at 16ms.
- Doesn't respect the fact that with current virtual EDID timing set,
not all resolutions are running at 60Hz. For example, current virtual
EDID also supports refresh rate at 56Hz, 59.97Hz, 60Hz, 75Hz, etc.
- Current vblank emulator use single hrtimer for all vGPUs. Regardsless
the possibility that different guests could run in different
resolutions, all vsync interrupts are injected at 16ms interval with
same hrtimer.
Based on previous patch which decode guest expected refresh rate from
vreg, the vblank emulator refactor patch makes following changes:
- Change the vblank emulator hrtimer from gvt global to per-vGPU.
By doing this, each vGPU display can operates at different refresh
rates. Currently only one dislay is supported for each vGPU so per-vGPU
hrtimer is enough. If multiple displays are supported per-vGPU in
future, we can expand to per-PIPE further.
- Change the fixed hrtimer period from 16ms to dynamic based on vreg.
GVT is expected to emulate the HW as close as possible. So reflacting
the accurate vsync interrupt interval is more correct than fixed 16ms.
- Change the vblank timer period and start the timer on PIPECONF change.
The initial period is updated to 16666667 based on 60Hz refresh rate.
According to PRM, PIPECONF controls the timing generator of the
connected display on this pipe, so it's safe to stop hrtimer on
PIPECONF disabling, and re-start hrtimer at new period on enabling.
Other changes including:
- Move vblank_timer_fn from irq.c into display.c.
- Clean per-vGPU vblank timer at clean_display instead of clean_irq.
To run quick test, launch a web browser and goto URL: www.displayhz.com
The actual refresh rate from guest can now always match guest settings.
V2:
Rebase to 5.11.
Remove unused intel_gvt_clean_irq().
Simplify enable logic in update_vblank_emulation(). (zhenyu)
Loop all vGPU by idr when check all vblank timer. (zhenyu)
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210226044630.284269-1-colin.xu@intel.com
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The headers in the gem/selftests/, gt/selftests, gvt/, selftests/
directories have never been compile-tested, but it would be possible
to make them self-contained.
This commit only addresses missing <linux/types.h> and forward
struct declarations.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.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/20191108094142.25942-1-yamada.masahiro@socionext.com
This patch introduces a command scanner to scan guest command buffers.
Signed-off-by: Yulei Zhang <yulei.zhang@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the GVT-g display virtualization.
It consists a collection of display MMIO handlers, like power well register
handler, pipe register handler, plane register handler, which will emulate
all display MMIOs behavior to support virtual mode setting sequence for
guest.
Signed-off-by: Bing Niu <bing.niu@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces vGPU interrupt emulation framework.
The vGPU intrerrupt emulation framework is an event-based interrupt
emulation framework. It's responsible for emulating GEN hardware interrupts
during emulating other HW behaviour.
It consists several components:
- Descriptions of interrupt register bit
- Upper level <-> lower level interrupt mapping
- GEN HW IER/IMR/IIR register emulation routines
- Event-based interrupt propagation interface
When a GVT-g component wants to inject an interrupt to a VM during a
emulation, first it should specify the event needs to be emulated and the
framework will deal with the rest of emulation:
- Generating related virtual IIR bit according to virtual IER and IMRs,
- Generate related virtual upper level virtual IIR bit accodring to the
per-platform interrupt mapping
- Injecting a MSI to VM
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Colin Xu