[PATCH 0/5] [SRU][C/master] Reduce boot noise on Dragonboard

Paolo Pisati paolo.pisati at canonical.com
Wed Oct 10 15:51:27 UTC 2018

BugLink: https://bugs.launchpad.net/bugs/1797154


During boot on a Dragonboard410c using a recent Bionic or Cosmic kernel,
there's some noise like:

[ 3.665431] msm_dsi_phy 1a98300.dsi-phy: Failed to get supply 'vddio':
[ 3.669243] msm_dsi_phy 1a98300.dsi-phy: dsi_phy_regulator_init: failed
to init regulator, ret=-517
[ 3.676180] msm_dsi_phy 1a98300.dsi-phy: dsi_phy_driver_probe: failed to
init regulator


[ 4.192280] qcom,pm8916-wcd-spmi-codec 200f000.spmi:pm8916 at 1:codec at f000:
Failed to get supply 'vdd-cdc-io': -517
[ 4.195660] qcom,pm8916-wcd-spmi-codec 200f000.spmi:pm8916 at 1:codec at f000:
Failed to get regulator supplies -517

and similar.

This is mainly due to DRM_MSM* and SND_QCOM_MSM* that were built-in, and
try to initialize before the voltage regulators are ready to work,
resulting in a noisy bootlog.

These patches factor out some code as modules, so when the kmods are
loaded and initialized, regulators are already present and ready to
attach - all these config changes shave around ~3K bytes from dmesg,
making the bootlog easir to parse.


Apply the attached patches and recompile

How to test:

Boot a patched kernel and check for the above noise in dmesg

Regression potential:

None, we are just turning some code into kmods, and turning off a couple
of not used feature for this flavour - all the other flavours are

Paolo Pisati (5):
  UBUNTU: [Config] arm64: snapdragon: DRM_MSM=m
  UBUNTU: [Config] arm64: snapdragon: SND*=m
  UBUNTU: [Config] arm64: snapdragon: disable ARM_SDE_INTERFACE
  UBUNTU: [Config] arm64: snapdragon: disable DRM_I2C_ADV7511_CEC
  UBUNTU: [Config] arm64: snapdragon: disable VIDEO_ADV7511,

 .../config/amd64/config.common.amd64          |  6 ++---
 .../config/arm64/config.common.arm64          |  7 ++++++
 .../config/arm64/config.flavour.generic       | 22 ++++---------------
 .../config/arm64/config.flavour.snapdragon    | 22 ++++---------------
 .../config/armhf/config.common.armhf          | 14 +++---------
 debian.master/config/config.common.ubuntu     | 19 ++++++++++------
 debian.master/config/i386/config.common.i386  |  6 ++---
 .../config/ppc64el/config.common.ppc64el      |  7 +++---
 8 files changed, 37 insertions(+), 66 deletions(-)


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