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>
Guest OS builds up its timing mode list based on the virtual EDID as
simulated by GVT. However since there are several timings supported in
the virtual EDID, and each timing can also support several modes
(resolution and refresh rate), current emulated vblank period (16ms)
may not always be correct and could lead to miss-sync behavior in guest.
Guest driver will setup new resolution and program vregs accordingly and
it should always follows GEN PRM. Based on the simulated display regs by
GVT, it's safe to decode the actual refresh rate using by guest from
vreg only.
Current implementation only enables PIPE_A and PIPE_A is always tied to
TRANSCODER_A in HW. GVT may simulate DP monitor on PORT_B or PORT_D
based on the caller. So we can find out which DPLL is used by PORT_x
which connected to TRANSCODER_A and calculate the DP bit rate from the
DPLL frequency. Then DP stream clock (pixel clock) can be calculated
from DP link M/N and DP bit rate. Finally, get the refresh rate from
pixel clock, H total and V total.
The per-vGPU accurate refresh rate is not used yet but only stored,
until per-vGPU vblank timer is enabled. Then each vGPU can have
different and accurate refresh rate per-guest driver configuration.
Refer to PRM for GEN display and VESA timing standard for more details.
V2:
Rebase to 5.11.
Correctly calculate DP link rate for BDW and BXT.
Use GVT_DEFAULT_REFRESH_RATE instead of hardcoded to 60 as init refresh.
Typo fix. (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/20210226044559.283622-1-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
These functions will get default resolution according to vgpu type.
Signed-off-by: Hang Yuan <hang.yuan@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch is to introduce the framebuffer decoder which can decode guest
OS's framebuffer information, including primary, cursor and sprite plane.
v16:
- rebase to 4.14.0-rc6.
v14:
- refine pixel format table. (Zhenyu)
v9:
- move drm format change to a separate patch. (Xiaoguang)
v8:
- fix a bug in decoding primary plane. (Tina)
v7:
- refine framebuffer decoder code. (Zhenyu)
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This assigns resolution definition for each vGPU type. For smaller
resource type we should limit max resolution, so e.g limit to 1024x768
for 64M type, others are still default to 1920x1200.
v2: Fix for actual 1920x1200 resolution
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We'll need to apply different resolution for vgpu types, so this
adds more EDID types definition.
v2: fix typo for actual 1920x1200 resolution
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We also need reset vGPU virtual display emulation. Since all vreg has
been cleared, we need reset display related vreg to reflect our display
setting.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Ping Gao <ping.a.gao@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>
Colin Xu