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Author SHA1 Message Date
Douglas Anderson
b9364eed92 drm/msm/dpu: Move min BW request and full BW disable back to mdss
In commit a670ff578f ("drm/msm/dpu: always use mdp device to scale
bandwidth") we fully moved interconnect stuff to the DPU driver. This
had no change for sc7180 but _did_ have an impact for other SoCs. It
made them match the sc7180 scheme.

Unfortunately, the sc7180 scheme seems like it was a bit broken.
Specifically the interconnect needs to be on for more than just the
DPU driver's AXI bus. In the very least it also needs to be on for the
DSI driver's AXI bus. This can be seen fairly easily by doing this on
a ChromeOS sc7180-trogdor class device:

  set_power_policy --ac_screen_dim_delay=5 --ac_screen_off_delay=10
  sleep 10
  cd /sys/bus/platform/devices/ae94000.dsi/power
  echo on > control

When you do that, you'll get a warning splat in the logs about
"gcc_disp_hf_axi_clk status stuck at 'off'".

One could argue that perhaps what I have done above is "illegal" and
that it can't happen naturally in the system because in normal system
usage the DPU is pretty much always on when DSI is on. That being
said:
* In official ChromeOS builds (admittedly a 5.4 kernel with backports)
  we have seen that splat at bootup.
* Even though we don't use "autosuspend" for these components, we
  don't use the "put_sync" variants. Thus plausibly the DSI could stay
  "runtime enabled" past when the DPU is enabled. Techncially we
  shouldn't do that if the DPU's suspend ends up yanking our clock.

Let's change things such that the "bare minimum" request for the
interconnect happens in the mdss driver again. That means that all of
the children can assume that the interconnect is on at the minimum
bandwidth. We'll then let the DPU request the higher amount that it
wants.

It should be noted that this isn't as hacky of a solution as it might
initially appear. Specifically:
* Since MDSS and DPU individually get their own references to the
  interconnect then the framework will actually handle aggregating
  them. The two drivers are _not_ clobbering each other.
* When the Qualcomm interconnect driver aggregates it takes the max of
  all the peaks. Thus having MDSS request a peak, as we're doing here,
  won't actually change the total interconnect bandwidth (it won't be
  added to the request for the DPU). This perhaps explains why the
  "average" requested in MDSS was historically 0 since that one
  _would_ be added in.

NOTE also that in the downstream ChromeOS 5.4 and 5.15 kernels, we're
also seeing some RPMH hangs that are addressed by this fix. These
hangs are showing up in the field and on _some_ devices with enough
stress testing of suspend/resume. Specifically right at suspend time
with a stack crawl that looks like this (from chromeos-5.15 tree):
  rpmh_write_batch+0x19c/0x240
  qcom_icc_bcm_voter_commit+0x210/0x420
  qcom_icc_set+0x28/0x38
  apply_constraints+0x70/0xa4
  icc_set_bw+0x150/0x24c
  dpu_runtime_resume+0x50/0x1c4
  pm_generic_runtime_resume+0x30/0x44
  __genpd_runtime_resume+0x68/0x7c
  genpd_runtime_resume+0x12c/0x20c
  __rpm_callback+0x98/0x138
  rpm_callback+0x30/0x88
  rpm_resume+0x370/0x4a0
  __pm_runtime_resume+0x80/0xb0
  dpu_kms_enable_commit+0x24/0x30
  msm_atomic_commit_tail+0x12c/0x630
  commit_tail+0xac/0x150
  drm_atomic_helper_commit+0x114/0x11c
  drm_atomic_commit+0x68/0x78
  drm_atomic_helper_disable_all+0x158/0x1c8
  drm_atomic_helper_suspend+0xc0/0x1c0
  drm_mode_config_helper_suspend+0x2c/0x60
  msm_pm_prepare+0x2c/0x40
  pm_generic_prepare+0x30/0x44
  genpd_prepare+0x80/0xd0
  device_prepare+0x78/0x17c
  dpm_prepare+0xb0/0x384
  dpm_suspend_start+0x34/0xc0

We don't completely understand all the mechanisms in play, but the
hang seemed to come and go with random factors. It's not terribly
surprising that the hang is gone after this patch since the line of
code that was failing is no longer present in the kernel.

Fixes: a670ff578f ("drm/msm/dpu: always use mdp device to scale bandwidth")
Fixes: c33b7c0389 ("drm/msm/dpu: add support for clk and bw scaling for display")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Tested-by: Jessica Zhang <quic_jesszhan@quicinc.com> # RB3 (sdm845) and
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/487884/
Link: https://lore.kernel.org/r/20220531160059.v2.1.Ie7f6d4bf8cce28131da31a43354727e417cae98d@changeid
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
2022-06-01 16:16:19 -07:00
Douglas Anderson
5419900995 drm/msm: Fix shutdown
When rebooting on my sc7280-herobrine based device, I got a
crash. Upon debugging, I found that I was in msm_drv_shutdown() and my
"pdev" was the one associated with mdss_probe().

From source, I found that mdss_probe() has the line:
  platform_set_drvdata(pdev, mdss);
...where "mdss" is of type "struct msm_mdss *".

Also from source, I saw that in msm_drv_shutdown() we have the line:
  struct msm_drm_private *priv = platform_get_drvdata(pdev);

This is a mismatch and is the root of the problem.

Further digging made it apparent that msm_drv_shutdown() is only
supposed to be used for parts of the msm display framework that also
call msm_drv_probe() but mdss_probe() doesn't call
msm_drv_probe(). Let's remove the shutdown functon from msm_mdss.c.

Digging a little further, code inspection found that two drivers that
use msm_drv_probe() weren't calling msm_drv_shutdown(). Let's add it
to them.

Fixes: 6874f48bb8 ("drm/msm: make mdp5/dpu devices master components")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/484975/
Link: https://lore.kernel.org/r/20220504163900.v2.1.Iaebd35e60160fc0f2a50fac3a0bf3b298c0637c8@changeid
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-05-07 02:10:35 +03:00
Bjorn Andersson
3e9c146f49 drm/msm/dpu: Issue MDSS reset during initialization
It's typical for the bootloader to bring up the display for showing a
boot splash or efi framebuffer. But in some cases the kernel driver ends
up only partially configuring (in particular) the DPU, which might
result in e.g. that two different data paths attempts to push data to
the interface - with resulting graphical artifacts.

Naturally the end goal would be to inherit the bootloader's
configuration and provide the user with a glitch free handover from the
boot configuration to a running DPU.

But as implementing seamless transition from the bootloader
configuration to the running OS will be a considerable effort, start by
simply resetting the entire MDSS to its power-on state, to avoid the
partial configuration.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482796/
Link: https://lore.kernel.org/r/20220421041550.643964-2-bjorn.andersson@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-05-02 02:07:08 +03:00
Dmitry Baryshkov
6874f48bb8 drm/msm: make mdp5/dpu devices master components
The msm_mdss serves several roles at this moment. It provides IRQ domain
used by MDP5 and DPU drivers but it also serves as a component master
for both those usecases. MDP4 (which does not have separate MDSS device)
is the component master on it's own.
Remove this assymmetry and make both MDP5 and DPU component masters too.
This removes a need to care about drm/components from msm_mdss driver,
removes an mdss pointer from struct msm_drm_private and simplifies the
interface between mdp5/dpu and msm_drv.

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482512/
Link: https://lore.kernel.org/r/20220419155346.1272627-7-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-04-26 00:50:46 +03:00
Dmitry Baryshkov
dc43e923cd drm/msm: allow compile time selection of driver components
MSM DRM driver already allows one to compile out the DP or DSI support.
Add support for disabling other features like MDP4/MDP5/DPU drivers or
direct HDMI output support.

Suggested-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482508/
Link: https://lore.kernel.org/r/20220419155346.1272627-6-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-04-26 00:50:46 +03:00
Dmitry Baryshkov
5d44531be0 drm/msm: stop using device's match data pointer
Let's make the match's data pointer a (sub-)driver's private data. The
only user currently is the msm_drm_init() function, using this data to
select kms_init callback. Pass this callback through the driver's
private data instead.

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482510/
Link: https://lore.kernel.org/r/20220419155346.1272627-5-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-04-26 00:50:46 +03:00
Dmitry Baryshkov
ecb23f2e30 drm/msm: split the main platform driver
Currently the msm platform driver is a multiplex handling several cases:
- headless GPU-only driver,
- MDP4 with flat device nodes,
- MDP5/DPU MDSS with all the nodes being children of MDSS node.

This results in not-so-perfect code, checking the hardware version
(MDP4/MDP5/DPU) in several places, checking for mdss even when it can
not exist, etc. Split the code into three handling subdrivers (mdp4,
mdss and headless msm).

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482507/
Link: https://lore.kernel.org/r/20220419155346.1272627-4-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-04-26 00:50:46 +03:00
Dmitry Baryshkov
e1072257ff drm/msm: remove extra indirection for msm_mdss
Since now there is just one mdss subdriver, drop all the indirection,
make msm_mdss struct completely opaque (and defined inside msm_mdss.c)
and call mdss functions directly.

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482505/
Link: https://lore.kernel.org/r/20220419155346.1272627-3-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-04-26 00:50:46 +03:00
Dmitry Baryshkov
87729e2a78 drm/msm: unify MDSS drivers
MDP5 and DPU1 both provide the driver handling the MDSS region, which
handles the irq domain and (incase of DPU1) adds some init for the UBWC
controller. Unify those two pieces of code into a common driver.

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/482506/
Link: https://lore.kernel.org/r/20220419155346.1272627-2-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
2022-04-26 00:50:46 +03:00
Renamed from drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c (Browse further)