[PATCH 0/5] arm: mvebu: turris_omnia: Fix hangup in debug UART

[Pali Rohár]

If proper U-Boot on Turris Omnia tries to print something on debug UART
then CPU hangs. Reason is that debug UART in proper U-Boot for Turris
Omnia has incorrect configuration of base register. Base register is
different in SPL and also in different stages of proper U-Boot.

Fix all these issues. Introduce new arch_very_early_init() ARM function
which will be called at very early stage prior initialization of debug
UART. Move code which moves internal mvebu registers to this function.
And split configuration of DEBUG_UART_BASE into SPL and proper U-Boot
to allow setting different values which matches current HW status.

With all these changes, it is possible call "printf" function in
Turris Omnia's board_early_init_f() function in both SPL and proper
U-Boot.

Pali Rohár (5):
  arm: Add new config option ARCH_VERY_EARLY_INIT
  arm: mvebu: Move internal registers in arch_very_early_init() function
  serial: Add new config option SPL_DEBUG_UART_BASE
  serial: ns16550: Add support for SPL_DEBUG_UART_BASE
  arm: mvebu: turris_omnia: Fix DEBUG_UART_BASE

 arch/arm/Kconfig               |  6 ++++++
 arch/arm/lib/crt0.S            |  5 +++++
 arch/arm/mach-mvebu/Kconfig    |  1 +
 arch/arm/mach-mvebu/Makefile   |  1 +
 arch/arm/mach-mvebu/cpu.c      | 31 -------------------------------
 arch/arm/mach-mvebu/lowlevel.S | 27 +++++++++++++++++++++++++++
 configs/turris_omnia_defconfig |  3 ++-
 drivers/serial/Kconfig         |  7 +++++++
 drivers/serial/ns16550.c       |  4 ++--
 9 files changed, 51 insertions(+), 34 deletions(-)
 create mode 100644 arch/arm/mach-mvebu/lowlevel.S

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2.20.1