Call xxx_timer_initialize from clock subsystem to make timer ready for use as soon as possiblei and revert the workaround:
commit 0863e771a9
Author: Gregory Nutt <gnutt@nuttx.org>
Date: Fri Apr 26 07:24:57 2019 -0600
Revert "sched/clock/clock_initialize.c: clock_inittime() needs to be done with CONFIG_SCHED_TICKLESS and clock_initialize should skip clock_inittime() for external RTC case since the RTC isn't ready yet."
This reverts commit 2bc709d4b9.
Commit 2bc709d4b9 was intended to handle the case where up_timer_gettime may not start from zero case. However, this change has the side-effect of breaking every implementation of tickless mode: After this change the tickless timer structures are used before they are initialized in clock_inittime(). Initialization happens later when up_initialize is called() when arm_timer_initialize().
Since the tickless mode timer is very special, one solution might be to
1. Rename xxx_timer_initialize to up_timer_initialize
2 Move up_timer_initialize to include/nuttx/arch.h
3. Call it from clock subsystem instead up_initialize
Basically, this change make timer initialization almost same as rtc initialization(up_rtc_initialize).
For now, however, we just need to revert the change.
This change removes the board_reset() implementation from the architecture-specific code and re-implements in the src/ directory of each board that has CONFIG_BOARDCTL_RESET enabled. That is the correct functional partitioning.
drivers/serial/uart_16550.c: Add a configuration, analogous to the STM32 configuration option, to suppress the NuttX standard re-ordering for /dev/ttySN for special case of the 16550 UART.
config/serial: UART 16550: Add CONFIG_SERIAL_UART_ARCH_MMIO option so the a memory mapped device doesn't need to provide uart_getreg() and uart_putreg() implementations.
u16550_txempty() should check UART_LSR_TEMT to avoid some data left in the transmit FIFO
Provide a user defined callback context for irq's, such that when
registering a callback users can provide a pointer that will get
passed back when the isr is called.