[U-Boot] [PATCH v4 0/9] arm: exynos: Fix reboot on Odroid HC1

[Krzysztof Kozlowski]

Hi,

Changes since v3
================
1. Add accumulated review and test tags.
2. Patch 6: Add "ramp" keyword to new function (as discussed with
   Torsten Duwe).
3. Rebased on v2019.04-rc3.


Changes since v2
================
1. Add Lukasz review tags.
2. Patch 7: Return on error, as suggested by Simon.
2. Patch 3: Use IS_ENABLED() to run revision detection only
   once - either during late display board or misc_init_r.

Changes since v1
================
1. Move fixes to beginning of patchset.
2. Patch 3: Rework the idea - split revision detection to be executed later.
3. Patch 4: New patch.
4. Patch 6: Apply Simon's comments.
5. Patch 6: Do not delay when changing voltage if regulator is disabled.
6. Patch 6: Do not delay when disabling the regulator.


Description
===========
Odroid HC1 does not reboot properly (at least from SD card but
I do not expect difference on eMMC), if LDO4/VDD_ADC was turned
off by Linux kernel.  This condition happens so far always, because
Linux kernel did not enable ADC on Odroid HC1, therefore the
VDD_ADC regulator was turned off as unused.

The issue is in detection of revision which later is used to load
proper DTB.

The revision is obtained by ADC read of a voltage depending on VDD_ADC.
Therefore:
1. VDD_ADC has to be turned on (but board detection happens before
   power is initialized),
2. Turning VDD_ADC should wait with ramp delay,
3. Reading the value from ADC should wait for it to stabilize.

Tested on Odroid XU3-Lite and Odroid HC1.

Comments and testing are welcomed.

Best regards,
Krzysztof

Krzysztof Kozlowski (9):
  adc: exynos-adc: Fix wrong bit operation used to stop the ADC
  power: regulator: s2mps11: Fix step for LDO27 and LDO35
  arm: exynos: Detect revision later, when all resources are ready
  arm: exynos: odroid-xu3: Display info late to have proper type
  arm: exynos: Wait till ADC stabilizes before checking Odroid HC1
    revision
  regulator: Add support for ramp delay
  power: regulator: s2mps11: Add enable delay
  arm: dts: exynos: Add supply for ADC block to Odroid XU3 family
  arm: dts: exynos: Add ramp delay property to LDO regulators to Odroid
    XU3 family

 arch/arm/dts/exynos5422-odroidxu3.dts         | 20 +++++++
 board/samsung/common/board.c                  | 24 ++++++++-
 board/samsung/common/exynos5-dt-types.c       | 54 +++++++++++++++++--
 board/samsung/odroid/odroid.c                 |  8 +++
 configs/odroid-xu3_defconfig                  |  2 +
 .../regulator/regulator.txt                   |  2 +
 drivers/adc/exynos-adc.c                      |  2 +-
 drivers/power/regulator/regulator-uclass.c    | 47 +++++++++++++++-
 drivers/power/regulator/s2mps11_regulator.c   | 15 +++++-
 include/power/regulator.h                     |  2 +
 include/samsung/misc.h                        |  1 +
 11 files changed, 167 insertions(+), 10 deletions(-)

-- 
2.17.1