Upon boot the RTC early-init function should detect if LSE or LSI is
already selected/running and, if so, use it. When the LSI has previously
(in the previous reset cycle) been selected as the clock source the only
way to reliably tell is if the RTCSEL bits of the RCC_BDCR are set to the
correct LSI value. In particular the RCC_CSR bits for LSI control do not
indicate if the LSI is ready even if it is selected.
This patch removes the check on the RCC_CSR bits for the LSI being on and
ready and only uses the check on the RCC_BDCR to see if the LSI should be
used straightaway. This was tested on a PYBLITEv1.0 and with the patch the
LSI persists correctly as the RTC source as long as the backup domain
remains powered.
Previously, if LSE is selected but fails and the RTC falls back to LSI,
then the rtc_info flags would incorrectly state that LSE is used. This
patch fixes that by setting the bit in rtc_info only after the clock is
ready.
There is an underlying hardware SPI driver (built on top of the STM HAL)
and then on top of this sits the legacy pyb.SPI class as well as the
machine.SPI class. This patch improves the separation between these
layers, in particular decoupling machine.SPI from pyb.SPI.
This patch combines the compiler optimisation code for double and triple
tuple-to-tuple assignment, taking it from two separate if-blocks to one
combined if-block. This can be done because the code for both of these
optimisations has a lot in common. Combining them together reduces code
size for ports that have the triple-tuple optimisation enabled (and doesn't
change code size for ports that have it disabled).
The SPI sub-system is independent from the uPy state (eg the heap) and so
can safely persist across a soft reset. And this is actually necessary for
drivers that rely on SPI and that also need to persist across soft reset
(eg external SPI flash memory).
This patch adds support in the USBD configuration and CDC-MSC-HID class for
high-speed USB mode. To enable it the board configuration must define
USE_USB_HS, and either not define USE_USB_HS_IN_FS, or be an STM32F723 or
STM32F733 MCU which have a built-in HS PHY. High-speed mode is then
selected dynamically by passing "high_speed=True" to the pyb.usb_mode()
function, otherwise it defaults to full-speed mode.
This patch has been tested on an STM32F733.
By defining MICROPY_HW_USB_MAIN_DEV a given board can select to use either
USB_PHY_FS_ID or USB_PHY_HS_ID as the main USBD peripheral, on which the
REPL will appear. If not defined this will be automatically configured.
There's no need to have these as separate functions, they just take up
unnecessary code space and combining them allows to factor common code, and
also allows to support arbitrary string descriptor indices.
Damien George
liamkinne