The motivation for doing this is so that we can allow
common_hal_mcu_disable_interrupts in IRQ context, something that works
on other ports, but not on nRF with SD enabled. This is because
when SD is enabled, calling sd_softdevice_is_enabled in the context
of an interrupt with priority 2 or 3 causes a HardFault. We have chosen
to give the USB interrupt priority 2 on nRF, the highest priority that
is compatible with SD.
Since at least SoftDevice s130 v2.0.1, sd_nvic_critical_region_enter/exit
have been implemented as inline functions and are safe to call even if
softdevice is not enabled. Reference kindly provided by danh:
https://devzone.nordicsemi.com/f/nordic-q-a/29553/sd_nvic_critical_region_enter-exit-missing-in-s130-v2
Switching to these as the default/only way to enable/disable interrupts
simplifies things, and fixes several problems and potential problems:
* Interrupts at priority 2 or 3 could not call common_hal_mcu_disable_interrupts
because the call to sd_softdevice_is_enabled would HardFault
* Hypothetically, the state of sd_softdevice_is_enabled
could change from the disable to the enable call, meaning the calls
would not match (__disable_irq() could be balanced with
sd_nvic_critical_region_exit).
This also fixes a problem I believe would exist if disable() were called
twice when SD is enabled. There is a single "is_nested_critical_region"
flag, and the second call would set it to 1. Both of the enable()
calls that followed would call critical_region_exit(1), and interrupts
would not properly be reenabled. In the new version of the code,
we use our own nesting_count value to track the intended state, so
now nested disable()s only call critical_region_enter() once, only
updating is_nested_critical_region once; and only the second enable()
call will call critical_region_exit, with the right value of i_n_c_r.
Finally, in port_sleep_until_interrupt, if !sd_enabled, we really do
need to __disable_irq, rather than using the common_hal_mcu routines;
the reason why is documented in a comment.
new file: ports/nrf/boards/raytac_mdbt50q-db-40/bootloader/6.0.0/pca10056_bootloader_6.0.0_s140.zip
new file: ports/nrf/boards/raytac_mdbt50q-db-40/mpconfigboard.h
new file: ports/nrf/boards/raytac_mdbt50q-db-40/mpconfigboard.mk
new file: ports/nrf/boards/raytac_mdbt50q-db-40/pins.c
Testing performed: That a card is successfully mounted on Pygamer with
the built in SD card slot
This module is enabled for most FULL_BUILD boards, but is disabled for
samd21 ("M0"), litex, and pca10100 for various reasons.
* Fix flash writes that don't end on a sector boundary. Fixes#2944
* Fix enum incompatibility with IDF.
* Fix printf output so it goes out debug UART.
* Increase stack size to 8k.
* Fix sleep of less than a tick so it doesn't crash.
This pulls all common functionality into `shared-bindings` and keeps
platform-specific code inside `nrf`. Additionally, this performs most
validation in the `shared-bindings` site.
The only validation that occurs inside platform-specific `common-hal`
code is related to timeout limits that are platform-specific.
Additionally, all documentation is now inside the `shared-bindings`
directory.
Signed-off-by: Sean Cross <sean@xobs.io>
The previous setting of `1` meant that the bluetooth system couldn't be
used when the watchdog timer was enabled.
Signed-off-by: Sean Cross <sean@xobs.io>
As part of the reset process, save the current tick count to an
uninitialized memory location. That way, the current tick value will be
preserved across reboots.
A reboot will cause us to lose a certain number of ticks, depending on
how long a reboot takes, however if reboots are infrequent then this
will not be a large amount of time lost.
Signed-off-by: Sean Cross <sean@xobs.io>
For `microcontroller.reset()`, don't manually call NVIC_SystemReset().
Instead, call the `port_reset()` in case the port wants to do any
cleanup.
Signed-off-by: Sean Cross <sean@xobs.io>
This finishes the rework of the exception handler, which is once
again stored inside the watchdog timer module.
This also implements a `watchdog_reset()` that is used to disable the
RAISE watchdog, if one is enabled.
Signed-off-by: Sean Cross <sean@xobs.io>