stm32f4: re-implement using cmsis device headers

This drops the libopencm3 dependency, and adds libusb_stm32 and the cmsis
device headers for the stm32f4.  Functionality mirrors the gd32f4 port.
Support for the stm32f4[01][57] is dropped due to the DMA errata, and
flashing relies on dual bank support.

.gitmodules

@@ -1,10 +1,13 @@
-[submodule "libopencm3"]
-	path = contrib/libopencm3
-	url = https://github.com/libopencm3/libopencm3
 [submodule "tinycbor"]
 	path = contrib/tinycbor
 	url = https://github.com/intel/tinycbor
 [submodule "CMSIS"]
 	path = contrib/CMSIS_5
 	url = https://github.com/ARM-software/CMSIS_5.git
 	shallow = true
+[submodule "contrib/cmsis_device_f4"]
+	path = contrib/cmsis_device_f4
+	url = https://github.com/STMicroelectronics/cmsis_device_f4.git
+[submodule "contrib/libusb_stm32"]
+	path = contrib/libusb_stm32
+	url = https://github.com/dmitrystu/libusb_stm32.git

Makefile

@@ -29,14 +29,16 @@ CFLAGS+=-Isrc/ -Isrc/platforms/common -Wall -Wextra -g -std=c11 -DGIT_DESCRIBE=\
 CFLAGS+=-I${TINYCBOR_DIR}/src
 LDFLAGS+= -lm -L${OBJDIR} -l:${TINYCBOR_LIB}
 
-OPENCM3_DIR=$(PWD)/contrib/libopencm3
-
 VPATH+=src src/platforms src/platforms/common
 DESTOBJS = $(addprefix ${OBJDIR}/, ${OBJS})
 
 $(OBJDIR):
 	mkdir -p ${OBJDIR}
 
+
+$(OBJDIR)/%.o: %.s
+	${AS} -c -o $@ $<
+
 $(OBJDIR)/%.o: %.c
 	${CC} ${CFLAGS} -MMD -c -o $@ $<
 

README.md

@@ -202,7 +202,7 @@ Requires:
 - GNU make
 - check (for unit tests)
 
-Before trying to compile, make sure to bring in the libopencm3 submodule:
+Before trying to compile, make sure to bring in submodules in contrib:
 ```
 git submodule update --init
 ```
@@ -250,28 +250,12 @@ scheduling latency), make sure the threads have permissions to be realtime, or
 otherwise constrain it to a single cpu.
 
 # Hardware
-The current primary hardware platform is an ST Micro STM32F407VGT
-microcontroller.  There are a few non-production-ready hardware designs
+The current supported microcontrollers are the STMicro STM32F427 and GigaDevice
+GD32F450/470.  There are a few non-production-ready hardware designs
 available under https://github.com/via/viaems-boards, though I would recommend
-anyone attempting to use those designs contact me.  The STM32F4-DISCOVERY board
-*can* be used with this firmware, with appropriate extra hardware for vehicle
-interfacing.
+anyone attempting to use those designs contact me. Details on each platform are
+available in the README files in their platform directories.
 
+## [STM32F4](src/platforms/stm32f4/README.md)
 
-## STM32F4
-Note: These are subject to change with the next hardware design, which will be
-moving to better support a 64 pin chip and more flexible PWM outputs.
-
-System | Pins
---- | ---
-Trigger 0 | `PA0`
-Trigger 1 | `PA1`
-Frequency | `PA0`, `PA1`, `PA2`, `PA3`
-Test Trigger | `PB10`, `PB11`
-`CANL` | `PB5`
-`CANH` | `PB6`
-USB | `PA9`, `PA11`, and `PA12`
-ADC | `PB12`, `PB13`, `PB14`, and `PB15`
-OUT | `PD0`-`PD15`
-GPIO | `PE0`-`PE15`
-PWM | `PC6`, `PC7`, `PC8`, and `PC9` (currently all fixed at same frequenty)
+## [GD32F4](src/platforms/gd32f4/README.md)

src/platforms/common/ad7888_adc.h

@@ -62,4 +62,9 @@ static inline bool adc_response_is_valid(const uint16_t *values) {
   return true;
 }
 
+/* Not implemented */
+static void process_knock_inputs(const uint16_t *values) {
+  (void)values;
+}
+
 #endif