clock.c: The MSP430 may need nop instructions after (and in some cases
even before) touching the global interrupt enable bit in the
status register. The assembler generates a warning when in
doubt. Those nops should not be needed in our cases, but maybe
it is better two waste flash for two instructions than having
to live with the warning.
cpu.c: drop unneeded include
The assumption that every MCU has this feature turned out wrong. Hence,
add a feature to allow testing for support of edge triggered IRQs on
both flanks.
The API was based on the assumption that GPIO ports are mapped in memory
sanely, so that a `GPIO_PORT(num)` macro would work allow for constant
folding when `num` is known and still be efficient when it is not.
Some MCUs, however, will need a look up tables to efficiently translate
GPIO port numbers to the port's base address. This will prevent the use
of such a `GPIO_PORT(num)` macro in constant initializers.
As a result, we rather provide `GPIO_PORT_0`, `GPIO_PORT_1`, etc. macros
for each GPIO port present (regardless of MCU naming scheme), as well as
`GPIO_PORT_A`, `GPIO_PORT_B`, etc. macros if (and only if) the MCU port
naming scheme uses letters rather than numbers.
These can be defined as macros to the peripheral base address even when
those are randomly mapped into the address space. In addition, a C
function `gpio_port()` replaces the role of the `GPIO_PORT()` and
`gpio_port_num()` the `GPIO_PORT_NUM()` macro. Those functions will
still be implemented as efficient as possible and will allow constant
folding where it was formerly possible. Hence, there is no downside for
MCUs with sane peripheral memory mapping, but it is highly beneficial
for the crazy ones.
There are also two benefits for the non-crazy MCUs:
1. We can now test for valid port numbers with `#ifdef GPIO_PORT_<NUM>`
- This directly benefits the test in `tests/periph/gpio_ll`, which
can now provide a valid GPIO port for each and every board
- Writing to invalid memory mapped I/O addresses was treated as
triggering undefined behavior by the compiler and used as a
optimization opportunity
2. We can now detect at compile time if the naming scheme of the MCU
uses letters or numbers, and produce more user friendly output.
- This is directly applied in the test app
`thread_measure_stack_free()` previously assumed that reading past the
stack is safe. When the stack was indeed part of a thread, the
`thread_t` structure is put after the stack, increasing the odds of
this assumption to hold. However, `thread_measure_stack_free()` could
also be used on the ISR stack, which may be allocated at the end of
SRAM.
A second parameter had to be added to indicate the stack size, so that
reading past the stack can now be prevented.
This also makes valgrind happy on `native`/`native64`.
This changes a bunch of things that allows building with the musl C lib,
provided that `libucontext-dev` and `pkg-config` are installed.
Note that installing libucontext makes absolutely zero sense on C libs
that do natively provide this deprecated System V API, such as glibc.
Hence, it no sane glibc setup is expected to ever have libucontext
installed.
A main pain point was that argv and argc are expected to be passed to
init_fini handlers, but that is actually a glibc extension. This just
parses `/proc/self/cmdline` by hand to populate argv and argc during
startup, unless running on glibc.
Following best practice, this patch adds the module's header as its
first include. Resulting compiler errors are also fixed by adding the
header's missing include of cpu_conf.h.
This gets rid of a long list of boards with network interfaces and
instead let's boards (or MCUs with peripheral network interfaces)
provide the netif feature.
The apps that before used the long list are not depending on the
feature instead (in case of the default example, this is an
optional dependency).
Co-authored-by: mguetschow <mikolai.guetschow@tu-dresden.de>
Co-authored-by: mewen.berthelot <mewen.berthelot@orange.com>
This patch allows boards to select a max ADC clock speed. This could be
handy if the board wants to clock the ADC differently according to the
board's front end analog circuitry or MCU model's ADC capabilities.
- `printf "%d" ""` triggers an "invalid number" warning on ash, so
let's use `0` as portable default for zero
- add quotes where needed to make shellcheck happy
- `gpio_ll_toggle()` now is race-free
- avoid using a look up table but branch to the two different registers
in the `gpio_ll*()` functions
- in most cases the GPIO port is a compile time constant and the
dead branch is eliminated by the optimizer, making this vastly
more efficient
- some MCUs do only have a single port, in which case
`GPIO_PORT_NUM(port)` is known to return `0` even if `port` is
not known, resulting in one of the branch being eliminated as
dead branch no matter what
- in case it really is unknown at compile time which port to work
on, the branch can still be implemented efficiently by the
compiler e.g. using a conditional move; likely more efficient
than fetching a value from the look up table.
This implements `pm_set_lowest()` for the MSP430. Unlike most other
platforms, it intentionally does not use pm_layered. It is pretty
similar to `pm_layered` in that is does use reference counters, but it
uses them for two independent clock sources.
The main difference is that the low frequency clock domain can be
disabled even when the high frequency clock is still active. With the
layers, disabling layer n-1 while layer n is still blocked would not
work.
For super low symbol rates the auxiliary clock (ACLK) is used to
conserve power. But with only 32,678 Hz clock just prescaling will
result in poor bit timing, hence correct modulation control settings
to compensate are needed. Since computing this is too expensive, a
look-up table (as switch statement) for the four most common symbol
rates was used.
The datasheet gave the prescaler values ordered by ascending symbol
rate, the switch statement was ordered descending.
This changes the order to match the datasheets order and matches the
correct prescaler setting to the corresponding symbol rate.
Fixes https://github.com/RIOT-OS/RIOT/issues/20620
Only call this instruction if a debug session is active otherwise it will trigger a hardfault
Signed-off-by: Dylan Laduranty <dylan.laduranty@mesotic.com>
- The validity test for the high frequency crystal did not take
into account the higher range supported by the MSP430 F2xx / G2xx
family. This fixes the issue.
- The CPU family used is exposed to C as `CPU_FAM_<NAME>` macro
- Unused headers where dropped
- The status register is aliased `SR`, so let's use that more readable
name.
