cpu/stm32_common: add DMA support for all stm32

[vincent-d]

Contribution description

This adds DMA support for all stm32.
STDIO UART works fine on nucleo-f091 and on b-l072z-lrwan1. But SPI doesn't work on b-l072z-lrwan1, not tested on nucleo-f091.
I'm not sure I'll have a lot of time to continue this soon.

Issues/PRs references

Follow-up #7658

[aabadie]

I'm not sure I'll have a lot of time to continue this soon.

@vincent-d, is it still the case ?

[vincent-d]

@vincent-d, is it still the case ?

Unfortunately, yes. But if you wish, you can take this over. It should be close to work.

[aabadie]

This PR needs a rebase.

I can confirm that DMA is not working with SPI on b-l072z-lrwan1. I didn't try either the f091.
I briefly looked at the code but have no idea what's wrong. It will require more investigation.

Otherwise, while looking at the code (correct me if I'm wrong), I have the impression that once periph_dma is required, all UART and SPI devices have to provide a configuration for it.
Would it be more simple/flexible that to make use of DMA in the periph implementation (spi.c/uart.c) only if a define (UART_USE_DMA, SPI_USE_DMA) is set in the board peripheral configuration.
This way it will be possible to keep DMA for UART on b-l072z-lrwan1 but not for SPI (since it doesn't work).

What do you think ?

[vincent-d]

Otherwise, while looking at the code (correct me if I'm wrong), I have the impression that once periph_dma is required, all UART and SPI devices have to provide a configuration for it.

I haven't re-checked it, but as far as I remember, it should be possible to disable dma per uart or spi, in that case, the dma field should be set to DMA_STREAM_UNDEF.

[vincent-d]

Rebased.

I think I found why it was not working on b-l027z-lrwan1: the sx127x driver disables interrupt before using spi functions (

RIOT/drivers/sx127x/sx127x_internal.c

Line 89 in e07ea98

cpsr = irq_disable();

) which breaks dma. I quickly tested with those lines commented and it does not stay stuck anymore, though I get stuck when trying ifconfig (with examples/default) but I don't know if it's related.

So it should be ready for review and merge.

[aabadie]

Small changes are required, see below.

the sx127x driver disables interrupt before using spi functions which breaks dma

I made the same analysis last week but I was unsure. We should fix this driver (and maybe others?) before merging this PR.
Normally using ifconfig with examples/default is not supposed to hang.

[vincent-d]

We should fix this driver (and maybe others?) before merging this PR.

I don't know why it has been implemented like that in the first place. I can provide a quick fix though.

[vincent-d]

A quick grep shows that cc110x and sc127x use irq_disable/irq_restore around spi transfers. So they should be fixed.

[vincent-d]

I finally found the remaining issue!

It was a stupid mistake with the channel selection when 2 streams were used at the same time.

It finally works with b-l072z-lrwan1!

I guess I should split the drivers (cc110x and sx127x) parts in one (or 2) PR?

[aabadie]

I guess I should split the drivers (cc110x and sx127x) parts in one (or 2) PR?

One PR for each would be better. Great that you could fix all issues.

[vincent-d]

See #10669 and #10670

[aabadie]

Tested in nucleo-f091rc: UART and SPI work. Also 313eb03 is merged now.

Now it would be great to provide a DMA configuration for at least one (nucleo) board of each STM32 remaining families (f0, f1, f2, f7, l4). We can share the work here if you don't have the time.

Also a minor nit in dma.c ;)

And we still need #10670 or #10340 to be merged first.

[vincent-d]

Cherry-picked some commits from @aabadie and updated config for b-l475-iot01a, STDIO UART works fine, SPI and second UART are not tested.

[aabadie]

For me this PR is complete: all STM32s have at least one board with a DMA configuration. The code changes are ok.
I tested the implementation on all boards and all worked.

#10670 is now merged. So please rebase and squash. I triggered Murdock to check if there are not any build issue but I think it will be fine.

ACK

[aabadie]

I triggered Murdock to check if there are not any build issue but I think it will be fine.

So Murdock found a remaining issue with C++ and the UART configuration struct, the dma related attributes were not at the right place for b-l072z-lrwan1 and b-l475e-iot01a boards. I (force) pushed
2d79213 to fix that.

Now everything is fine. You can squash at any time (be careful the branches have diverged).

[vincent-d]

Rebased and squashed

[aabadie]

CI is all green, let's go!

[vincent-d]

Thanks @aabadie !

[cladmi]

A git bisect pointed me to the commit 0b6bccb as breaking the thread tests for iotlab-m3.

I used this test to find the commit:

BOARD=iotlab-m3 make -C tests/thread_basic/ all flash test

Also these other ones are failing but did not bisect them.

- [tests/cond_order](tests/cond_order/test.failed)
- [tests/isr_yield_higher](tests/isr_yield_higher/test.failed)
- [tests/msg_try_receive](tests/msg_try_receive/test.failed)
- [tests/mutex_order](tests/mutex_order/test.failed)
- [tests/pipe](tests/pipe/test.failed)
- [tests/posix_semaphore](tests/posix_semaphore/test.failed)
- [tests/ps_schedstatistics](tests/ps_schedstatistics/test.failed)
- [tests/pthread_barrier](tests/pthread_barrier/test.failed)
- [tests/pthread_cooperation](tests/pthread_cooperation/test.failed)
- [tests/pthread_rwlock](tests/pthread_rwlock/test.failed)
- [tests/rmutex](tests/rmutex/test.failed)
- [tests/thread_basic](tests/thread_basic/test.failed)
- [tests/thread_exit](tests/thread_exit/test.failed)
- [tests/thread_flags](tests/thread_flags/test.failed)
- [tests/thread_msg](tests/thread_msg/test.failed)
- [tests/thread_msg_seq](tests/thread_msg_seq/test.failed)

It also showed me that the commit 08a85fb cannot compile as I guess required changes are introduced later.

/home/harter/work/git/RIOT/cpu/stm32_common/periph/uart.c:207:35: error: 'USART_ISR_TXE' undeclared (first use in this function); did you mean 'USART_SR_TXE'?
     while (!(dev(uart)->ISR_REG & USART_ISR_TXE)) {}
                                   ^~~~~~~~~~~~~
                                   USART_SR_TXE
/home/harter/work/git/RIOT/cpu/stm32_common/periph/uart.c:207:35: note: each undeclared identifier is reported only once for each function it appears in