- compile issues because of missing RTC_MAGIC #defines
- missing functionality based on RTC_MAGIC in RTC based on stm32_rtcounter.c
- IRQ setup from up_rtc_initialize was later reset in up_irqinitialize
- write access to backup registers without enabling access to backup domain
- possible races in set/cancel alarm
tested with STM32F103C8 only
device now wakes up from forced STANDBY mode by alarm
reload = timclk / info->frequency;
which I belive to be incorrect, it should be
reload = timclk / info->frequency - 1;
since starting to count from 0, if I want to output half of the TIM clock, I must count to 1 and not to 2.
Surely enough, the original code did output 140/3=47 MHz, while this correction does allow the output up to 70 MHz.
I am not sure this affects most users generating slow PWM (e.g. PX4) but for frequencies
close to the PCLK, indeed the difference becomes significant.
Trivially triggered with two or more threads write to regular syslog stream and to emergency stream. In this case, freeze happens because of mismatch of priv->ie (TXEIE == 0) and actually enabled interrupts in USART registers (TXEIE == 1), which leads to unhandled TXE interrupt
and causes interrupt storm for USART.
The reason was that the code hit the line "canerr("ERROR: No available mailbox\n");" in stm32_cansend, so can_xmit thinks it has sent the packet to the hardware, but actually has not. Therefore the transmit interrupt never happens which would call can_txdone, and so the size of the FIFO size does not decrease.
The reason why the code actually hit the mentioned line above, is because stm32can_txready uses a different (incomplete) condition than stm32can_send to determine if the mailbox can be used for sending, and thus can_xmit forwards the packet to stm32can_send. stm32can_txready considered mailboxes OK for sending if the mailbox was empty, but did not consider that mailboxes may not yet be used if the request completed bit is set - stm32can_txinterrupt has to process these mailboxes first.
Note that I have also modified stm32can_txinterrupt - I removed the if condition, because the CAN controller retries to send the packet until it succeeds. Also if the condition would not evaluate to true, can_txdone would not be called and the FIFO size would not decrease also.