I have a function where it should be impossible to reach the end, so I put in a safe-mode reset at the bottom:
```
int find_unused_slot(void) {
// precondition: you already verified that a slot was available
for (int i=0; i<NUM_SLOTS; i++) {
if( slot_free(i)) {
return i;
}
}
safe_mode_reset(MICROPY_FATAL_ERROR);
}
```
However, the compiler still gave a diagnostic, because safe_mode_reset was not declared NORETURN.
So I started by teaching the compiler that reset_into_safe_mode never returned. This leads at least one level deeper due to reset_cpu needing to be a NORETURN function. Each port is a little different in this area. I also marked reset_to_bootloader as NORETURN.
Additional notes:
* stm32's reset_to_bootloader was not implemented, but now does a bare reset. Most stm32s are not fitted with uf2 bootloaders anyway.
* ditto cxd56
* esp32s2 did not implement reset_cpu at all. I used esp_restart(). (not tested)
* litex did not implement reset_cpu at all. I used reboot_ctrl_write. But notably this is what reset_to_bootloader already did, so one or the other must be incorrect (not tested). reboot_ctrl_write cannot be declared NORETURN, as it returns unless the special value 0xac is written), so a new unreachable forever-loop is added.
* cxd56's reset is via a boardctl() call which can't generically be declared NORETURN, so a new unreacahble "for(;;)" forever-loop is added.
* In several places, NVIC_SystemReset is redeclared with NORETURN applied. This is accepted just fine by gcc. I chose this as preferable to editing the multiple copies of CMSIS headers where it is normally declared.
* the stub safe_mode reset simply aborts. This is used in mpy-cross.
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.
Since Actions passed on the previous commit, where this computed value
was checked against the specified value (if any), this is no net change,
except that we no longer need to specify it for particular boards or
ports.
These calls were all moved into `main.c`, however this call was not
removed from litex. As a result, litex was calling `board_init()` twice.
This is currently not a problem, as `fomu` is able to be initialized
twice without issue, however future boards may have issue with this.
This fixes#2991.
Signed-off-by: Sean Cross <sean@xobs.io>
* 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.
Manually specify available modules and disable any modules
that are currently unsupported on the litex target.
Signed-off-by: Sean Cross <sean@xobs.io>
The SPI flash on current Fomu firmware is slow. Circuitpython runs
XIP from SPI flash, and so execution time can also be slow. Ordinarily
this isn't a problem, however certain operations are time-sensitive.
In particular, USB function needs to be handled quickly in order to
prevent the host from re-enumerating the device.
Place several critical TinyUSB structures into RAM, as well as several
hot functions that are frequently called. This reduces execution time
at the expense of system memory, and greatly improves system stability.
Signed-off-by: Sean Cross <sean@xobs.io>
