targets,runtime,machine: add support for the stm32f469-disco board

The LEDs and button work; I haven't tested the SPI and I2C
configuration.

Makefile

@@ -453,6 +453,8 @@ ifneq ($(STM32), 0)
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=stm32f4disco-1      examples/pwm
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=stm32f469disco      examples/blinky1
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=lorae5              examples/blinky1
 	@$(MD5SUM) test.hex
 endif

README.md

@@ -43,7 +43,7 @@ See the [getting started instructions](https://tinygo.org/getting-started/) for
 
 You can compile TinyGo programs for microcontrollers, WebAssembly and Linux.
 
-The following 75 microcontroller boards are currently supported:
+The following 76 microcontroller boards are currently supported:
 
 * [Adafruit Circuit Playground Bluefruit](https://www.adafruit.com/product/4333)
 * [Adafruit Circuit Playground Express](https://www.adafruit.com/product/3333)
@@ -118,6 +118,7 @@ The following 75 microcontroller boards are currently supported:
 * [ST Micro "Nucleo" WL55JC](https://www.st.com/en/evaluation-tools/nucleo-wl55jc.html)
 * [ST Micro STM32F103XX "Bluepill"](https://stm32-base.org/boards/STM32F103C8T6-Blue-Pill)
 * [ST Micro STM32F407 "Discovery"](https://www.st.com/en/evaluation-tools/stm32f4discovery.html)
+* [ST Micro STM32F469 "Discovery"](https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-mpu-eval-tools/stm32-mcu-mpu-eval-tools/stm32-discovery-kits/32f469idiscovery.html)
 * [X9 Pro smartwatch](https://github.com/curtpw/nRF5x-device-reverse-engineering/tree/master/X9-nrf52832-activity-tracker/)
 * [The Things Industries Generic Node Sensor Edition](https://www.genericnode.com/docs/sensor-edition/)
 

src/machine/board_stm32f469disco.go

@@ -0,0 +1,79 @@
+// +build stm32f469disco
+
+package machine
+
+import (
+	"device/stm32"
+	"runtime/interrupt"
+)
+
+const (
+	LED         = LED_BUILTIN
+	LED1        = LED_GREEN
+	LED2        = LED_ORANGE
+	LED3        = LED_RED
+	LED4        = LED_BLUE
+	LED_BUILTIN = LED_GREEN
+	LED_GREEN   = PG6
+	LED_ORANGE  = PD4
+	LED_RED     = PD5
+	LED_BLUE    = PK3
+)
+
+const (
+	BUTTON = PA0
+)
+
+// UART pins
+const (
+	UART_TX_PIN = PB10
+	UART_RX_PIN = PB11
+)
+
+var (
+	UART3  = &_UART3
+	_UART3 = UART{
+		Buffer:            NewRingBuffer(),
+		Bus:               stm32.USART3,
+		TxAltFuncSelector: AF7_USART1_2_3,
+		RxAltFuncSelector: AF7_USART1_2_3,
+	}
+	DefaultUART = UART3
+)
+
+// set up RX IRQ handler. Follow similar pattern for other UARTx instances
+func init() {
+	UART3.Interrupt = interrupt.New(stm32.IRQ_USART3, _UART3.handleInterrupt)
+}
+
+// SPI pins
+const (
+	SPI1_SCK_PIN = PA5
+	SPI1_SDI_PIN = PA6
+	SPI1_SDO_PIN = PA7
+	SPI0_SCK_PIN = SPI1_SCK_PIN
+	SPI0_SDI_PIN = SPI1_SDI_PIN
+	SPI0_SDO_PIN = SPI1_SDO_PIN
+)
+
+// Since the first interface is named SPI1, both SPI0 and SPI1 refer to SPI1.
+// TODO: implement SPI2 and SPI3.
+var (
+	SPI0 = SPI{
+		Bus:             stm32.SPI1,
+		AltFuncSelector: AF5_SPI1_SPI2,
+	}
+	SPI1 = &SPI0
+)
+
+const (
+	I2C0_SCL_PIN = PB6
+	I2C0_SDA_PIN = PB9
+)
+
+var (
+	I2C0 = &I2C{
+		Bus:             stm32.I2C1,
+		AltFuncSelector: AF4_I2C1_2_3,
+	}
+)

src/machine/machine_stm32f4.go

@@ -616,16 +616,6 @@ func initRNG() {
 	stm32.RNG.CR.SetBits(stm32.RNG_CR_RNGEN)
 }
 
-func CPUFrequency() uint32 {
-	return 168000000
-}
-
-// Internal use: configured speed of the APB1 and APB2 timers, this should be kept
-// in sync with any changes to runtime package which configures the oscillators
-// and clock frequencies
-const APB1_TIM_FREQ = 42000000 * 2
-const APB2_TIM_FREQ = 84000000 * 2
-
 // Alternative peripheral pin functions
 const (
 	AF0_SYSTEM                = 0

src/machine/machine_stm32f40x.go

@@ -0,0 +1,15 @@
+//go:build stm32f4 && (stm32f405 || stm32f407)
+// +build stm32f4
+// +build stm32f405 stm32f407
+
+package machine
+
+func CPUFrequency() uint32 {
+	return 168000000
+}
+
+// Internal use: configured speed of the APB1 and APB2 timers, this should be kept
+// in sync with any changes to runtime package which configures the oscillators
+// and clock frequencies
+const APB1_TIM_FREQ = 42000000 * 2
+const APB2_TIM_FREQ = 84000000 * 2

src/machine/machine_stm32f469.go

@@ -0,0 +1,14 @@
+//go:build stm32f4 && stm32f469
+// +build stm32f4,stm32f469
+
+package machine
+
+func CPUFrequency() uint32 {
+	return 180000000
+}
+
+// Internal use: configured speed of the APB1 and APB2 timers, this should be kept
+// in sync with any changes to runtime package which configures the oscillators
+// and clock frequencies
+const APB1_TIM_FREQ = 45000000 * 2
+const APB2_TIM_FREQ = 90000000 * 2

src/runtime/runtime_stm32f469.go

@@ -0,0 +1,28 @@
+//go:build stm32f4 && stm32f469
+// +build stm32f4,stm32f469
+
+package runtime
+
+import "device/stm32"
+
+/*
+   clock settings
+   +-------------+--------+
+   | HSE         | 8mhz   |
+   | SYSCLK      | 180mhz |
+   | HCLK        | 180mhz |
+   | APB2(PCLK2) | 90mhz  |
+   | APB1(PCLK1) | 45mhz  |
+   +-------------+--------+
+*/
+const (
+	HSE_STARTUP_TIMEOUT = 0x0500
+	// PLL Options - See RM0386 Reference Manual pg. 148
+	PLL_M    = 8 // PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N
+	PLL_N    = 360
+	PLL_P    = 2 // SYSCLK = PLL_VCO / PLL_P
+	PLL_Q    = 7 // USB OTS FS, SDIO and RNG Clock = PLL_VCO / PLL_Q
+	PLL_R    = 6 // DSI
+	PLL_CFGR = PLL_M | (PLL_N << stm32.RCC_PLLCFGR_PLLN_Pos) | (((PLL_P >> 1) - 1) << stm32.RCC_PLLCFGR_PLLP_Pos) |
+		(1 << stm32.RCC_PLLCFGR_PLLSRC_Pos) | (PLL_Q << stm32.RCC_PLLCFGR_PLLQ_Pos) | (PLL_R << stm32.RCC_PLLCFGR_PLLR_Pos)
+)

targets/stm32f469.ld

@@ -0,0 +1,10 @@
+
+MEMORY
+{
+    FLASH_TEXT (rw) : ORIGIN = 0x08000000, LENGTH = 2M
+    RAM (xrw)       : ORIGIN = 0x20000000, LENGTH = 320K
+}
+
+_stack_size = 4K;
+
+INCLUDE "targets/arm.ld"

targets/stm32f469disco.json

@@ -0,0 +1,12 @@
+{
+  "inherits": ["cortex-m4"],
+  "build-tags": ["stm32f469disco", "stm32f469", "stm32f4", "stm32"],
+  "serial": "uart",
+  "linkerscript": "targets/stm32f469.ld",
+  "extra-files": [
+    "src/device/stm32/stm32f469.s"
+  ],
+  "flash-method": "openocd",
+  "openocd-interface": "stlink",
+  "openocd-target": "stm32f4x"
+}