- Moved compiler & linker flags from boards/common/msba2 to cpu/arm7_common
- Moved dependency to newlib nano to cpu/arm7_common
- Moved config to link in cpu/startup.o to cpu/arm7_common
- Removed stdio_init() from newlib's _init(), as this is too late in the boot
process to allow DEBUG()ing during periph_init()
- Added stdio_init() to the various cpu_init() routines of the ARM CPUs just
before periph_init()
Engineering sample A doesn't have a functional USB peripheral (errata
issue 94). This commit adds an assertion check for this revision to
prevent some developer headaches.
Instead of having a send buffer as member `esp_wifi` netdev, a local variable is used now as send buffer. This avoids the need for a locking mechanism and reduces the risk of deadlocks.
Receive call back function `_esp_wifi_rx_cb` is called from WiFi hardware driver with a pointer to a frame buffer that is allocated in the WiFi hardware driver. This frame buffer was freed immediately after copying its content to a single local receive buffer of the `esp_wifi` netdev. The local receive buffer remained occupied until the protocol stack had processed it. Further incoming packets were dropped. However, very often a number of subsequent WiFi frames are received at the same time before the first one is processed completely. Having the single local receive buffer to hold only one received frame, led to a number of lost packets, even at low network load. Therefore, a ringbuffer of rx_buf elements was introduced which doesn't store the frames directly but only references to the frame buffers allocated in WiFi hardware driver. Since there is enough memory to hold several frames, the frames buffers allocated in WiFi hardware driver aren't freed immediatly any longer but are kept until the frame is processed by the protocol stack. This results in a much less loss rate of packets.
Events of different type can be pending at the same time. Therefore it is not possible to use ascending identifiers for the presence of a pending event. Rather, each event type has to be represented by one bit. Thes bits ORed identify all types of pending events. In the esp_wifi_isr function all pending events are then handled in one call. Otherwise, some events might be lost.
Using flash size in megabits is deprecated by esptool.
Use the new megabyte notation.
WARNING: Flash size arguments in megabits like '8m' are deprecated.
Please use the equivalent size '1MB'.
Megabit arguments may be removed in a future release.
esptool.py v2.6
UART FIFO must contain only 1 byte when newlib's `printf` function is used. Otherwise, outputs that are still not sent over UART are lost when `printf` is called asynchronousely.
To avoid unresolved symbols for unused functions during linking, compiler option `-ffunction-sections` is used now. Linker option `--warn-unresolved-symbols` is removed to get errors if required symbols cannot be resolved.
The modules `newlib, `newlib_syscalls_default` and `stdio_uart` are now used by default for output to the UART interface. This also reduces the dependency rules.
The overridden stdio functions `puts`, `putchar` and `printf` were removed. Instead, the corresponding newlib functions are always used. Using the newlib functions fixes output conflicts when using `f *` functions like `fprintf`,` fputs`, ... with `stdout` as the file parameter.
Use the -gz option to compress ELF sections containing DWARF information.
This saves around 50% of disk space, without any side effects.
See https://gcc.gnu.org/onlinedocs/gcc-9.2.0/gcc/Debugging-Options.html#Debugging-Options
for more infomation on this option.
Some platforms have an outdated toolchain that does not support -gz so
the flag is blacklisted there. Even then, the results are quite impressive.
I used @cladmi's `buildtest` branch (https://github.com/cladmi/RIOT/tree/wip/du/buildtest)
with this change and compiled the `examples/default` application:
```
$ BUILD_IN_DOCKER=1 DOCKER="sudo docker" make -C examples/default buildtest-indocker
```
The size was obtained with:
```
$ find output -name "*.bin.bindirsize" -type f -exec tail -n1 '{}' \; | cut -f 1 | awk '{s+=$1} END {printf "%.0f", s}'
```
Results:
- Vanilla: 10328112 KB (~10GB).
- with -gz: 4982788 KB (~5GB).
This was inspired by #8496.
once hardware flow control is enabled, rts should only be initialized
after the uart is enabled by setting the UE flag. This is stated in the
stm32f4 errata.
in uart_poweroff the peripheral should be disabled through the register
instead of just disabling the peripheral clock. In uart_poweron the
peripheral should be enabled after enabling the clock.
Not explicitely disabling the peripheral causes some bad signals on the
uart line sometimes.
