stm32: Initial support for stm32f2 (#3001)

Initial support for stm32f2 in general and STM32F207 in particular.

Boots up and communicates on STM32F207VC.

Signed-off-by: Boleslaw Ciesielski <combolek@users.noreply.github.com>

4 files changed, 46 insertions, 6 deletions

diff --git a/src/stm32/Kconfig b/src/stm32/Kconfig
index 4e02798f..5d6ef82b 100644
--- a/src/stm32/Kconfig
+++ b/src/stm32/Kconfig
@@ -22,6 +22,9 @@ choice
     config MACH_STM32F103
         bool "STM32F103"
         select MACH_STM32F1
+    config MACH_STM32F207
+        bool "STM32F207"
+        select MACH_STM32F2
     config MACH_STM32F405
         bool "STM32F405"
         select MACH_STM32F4
@@ -43,6 +46,8 @@ config MACH_STM32F0
     bool
 config MACH_STM32F1
     bool
+config MACH_STM32F2
+    bool
 config MACH_STM32F4
     bool
 config HAVE_STM32_USBFS
@@ -51,7 +56,7 @@ config HAVE_STM32_USBFS
     default n
 config HAVE_STM32_USBOTG
     bool
-    default y if MACH_STM32F4
+    default y if MACH_STM32F2 || MACH_STM32F4
     default n
 
 config MCU
@@ -59,6 +64,7 @@ config MCU
     default "stm32f042x6" if MACH_STM32F042
     default "stm32f070xb" if MACH_STM32F070
     default "stm32f103xe" if MACH_STM32F103
+    default "stm32f207xx" if MACH_STM32F207
     default "stm32f405xx" if MACH_STM32F405
     default "stm32f407xx" if MACH_STM32F407
     default "stm32f446xx" if MACH_STM32F446
@@ -68,6 +74,7 @@ config CLOCK_FREQ
     default 48000000 if MACH_STM32F0
     default 64000000 if MACH_STM32F103 && STM32_CLOCK_REF_INTERNAL
     default 72000000 if MACH_STM32F103
+    default 120000000 if MACH_STM32F207
     default 168000000 if MACH_STM32F405 || MACH_STM32F407
     default 180000000 if MACH_STM32F446
 
@@ -76,6 +83,7 @@ config FLASH_SIZE
     default 0x8000 if MACH_STM32F042
     default 0x20000 if MACH_STM32F070
     default 0x10000 if MACH_STM32F103 # Flash size of stm32f103x8 (64KiB)
+    default 0x40000 if MACH_STM32F2
     default 0x80000 if MACH_STM32F4
 
 config RAM_START
@@ -87,6 +95,7 @@ config RAM_SIZE
     default 0x1800 if MACH_STM32F042
     default 0x4000 if MACH_STM32F070
     default 0x5000 if MACH_STM32F103 # Ram size of stm32f103x8 (20KiB)
+    default 0x20000 if MACH_STM32F207
     default 0x20000 if MACH_STM32F4
 
 config STACK_SIZE
@@ -94,19 +103,19 @@ config STACK_SIZE
     default 512
 
 choice
-    prompt "Bootloader offset" if MACH_STM32F407 || MACH_STM32F405 || MACH_STM32F103 || MACH_STM32F070
+    prompt "Bootloader offset" if MACH_STM32F207 || MACH_STM32F407 || MACH_STM32F405 || MACH_STM32F103 || MACH_STM32F070
     config STM32_FLASH_START_800
         bool "2KiB bootloader (HID Bootloader)" if MACH_STM32F103
     config STM32_FLASH_START_2000
         bool "8KiB bootloader (stm32duino)" if MACH_STM32F103 || MACH_STM32F070
     config STM32_FLASH_START_4000
-        bool "16KiB bootloader (HID Bootloader)" if MACH_STM32F405 || MACH_STM32F407
+        bool "16KiB bootloader (HID Bootloader)" if MACH_STM32F207 || MACH_STM32F405 || MACH_STM32F407
     config STM32_FLASH_START_5000
         bool "20KiB bootloader" if MACH_STM32F103
     config STM32_FLASH_START_7000
         bool "28KiB bootloader" if MACH_STM32F103
     config STM32_FLASH_START_8000
-        bool "32KiB bootloader (SKR-PRO)" if MACH_STM32F407
+        bool "32KiB bootloader (SKR-PRO or TFT35-V3.0)" if MACH_STM32F207 || MACH_STM32F407
     config STM32_FLASH_START_10000
         bool "64KiB bootloader (Alfawise)" if MACH_STM32F103
     config STM32_FLASH_START_0000
diff --git a/src/stm32/Makefile b/src/stm32/Makefile
index dc8768a2..98b52e4c 100644
--- a/src/stm32/Makefile
+++ b/src/stm32/Makefile
@@ -6,6 +6,7 @@ CROSS_PREFIX=arm-none-eabi-
 dirs-y += src/stm32 src/generic
 dirs-$(CONFIG_MACH_STM32F0) += lib/stm32f0
 dirs-$(CONFIG_MACH_STM32F1) += lib/stm32f1
+dirs-$(CONFIG_MACH_STM32F2) += lib/stm32f2
 dirs-$(CONFIG_MACH_STM32F4) += lib/stm32f4
 
 MCU := $(shell echo $(CONFIG_MCU))
@@ -13,6 +14,7 @@ MCU_UPPER := $(shell echo $(CONFIG_MCU) | tr a-z A-Z | tr X x)
 
 CFLAGS-$(CONFIG_MACH_STM32F0) += -mcpu=cortex-m0 -Ilib/stm32f0/include
 CFLAGS-$(CONFIG_MACH_STM32F1) += -mcpu=cortex-m3 -Ilib/stm32f1/include
+CFLAGS-$(CONFIG_MACH_STM32F2) += -mcpu=cortex-m3 -Ilib/stm32f2/include
 CFLAGS-$(CONFIG_MACH_STM32F4) += -mcpu=cortex-m4 -Ilib/stm32f4/include
 CFLAGS-$(CONFIG_MACH_STM32F4) += -mfpu=fpv4-sp-d16 -mfloat-abi=hard
 CFLAGS += $(CFLAGS-y) -D$(MCU_UPPER) -mthumb -Ilib/cmsis-core
@@ -31,6 +33,9 @@ src-$(CONFIG_MACH_STM32F0) += stm32/stm32f0_i2c.c
 src-$(CONFIG_MACH_STM32F1) += ../lib/stm32f1/system_stm32f1xx.c
 src-$(CONFIG_MACH_STM32F1) += stm32/stm32f1.c generic/armcm_timer.c
 src-$(CONFIG_MACH_STM32F1) += stm32/adc.c stm32/i2c.c
+src-$(CONFIG_MACH_STM32F2) += ../lib/stm32f2/system_stm32f2xx.c
+src-$(CONFIG_MACH_STM32F2) += stm32/stm32f4.c generic/armcm_timer.c
+src-$(CONFIG_MACH_STM32F2) += stm32/adc.c stm32/i2c.c
 src-$(CONFIG_MACH_STM32F4) += ../lib/stm32f4/system_stm32f4xx.c
 src-$(CONFIG_MACH_STM32F4) += stm32/stm32f4.c generic/armcm_timer.c
 src-$(CONFIG_MACH_STM32F4) += stm32/adc.c stm32/i2c.c
diff --git a/src/stm32/internal.h b/src/stm32/internal.h
index abe879c1..2538bbaa 100644
--- a/src/stm32/internal.h
+++ b/src/stm32/internal.h
@@ -8,6 +8,8 @@
 #include "stm32f0xx.h"
 #elif CONFIG_MACH_STM32F1
 #include "stm32f1xx.h"
+#elif CONFIG_MACH_STM32F2
+#include "stm32f2xx.h"
 #elif CONFIG_MACH_STM32F4
 #include "stm32f4xx.h"
 #endif
diff --git a/src/stm32/stm32f4.c b/src/stm32/stm32f4.c
index 9b5433af..bc8d0eb2 100644
--- a/src/stm32/stm32f4.c
+++ b/src/stm32/stm32f4.c
@@ -1,4 +1,4 @@
-// Code to setup clocks and gpio on stm32f4
+// Code to setup clocks and gpio on stm32f2/stm32f4
 //
 // Copyright (C) 2019  Kevin O'Connor <kevin@koconnor.net>
 //
@@ -119,6 +119,28 @@ DECL_CONSTANT_STR("RESERVE_PINS_crystal", "PH0,PH1");
 
 // Clock configuration
 static void
+enable_clock_stm32f20x(void)
+{
+#if CONFIG_MACH_STM32F207
+    uint32_t pll_base = 1000000, pll_freq = CONFIG_CLOCK_FREQ * 2, pllcfgr;
+    if (!CONFIG_STM32_CLOCK_REF_INTERNAL) {
+        // Configure 120Mhz PLL from external crystal (HSE)
+        uint32_t div = CONFIG_CLOCK_REF_FREQ / pll_base;
+        RCC->CR |= RCC_CR_HSEON;
+        pllcfgr = RCC_PLLCFGR_PLLSRC_HSE | (div << RCC_PLLCFGR_PLLM_Pos);
+    } else {
+        // Configure 120Mhz PLL from internal 16Mhz oscillator (HSI)
+        uint32_t div = 16000000 / pll_base;
+        pllcfgr = RCC_PLLCFGR_PLLSRC_HSI | (div << RCC_PLLCFGR_PLLM_Pos);
+    }
+    RCC->PLLCFGR = (pllcfgr | ((pll_freq/pll_base) << RCC_PLLCFGR_PLLN_Pos)
+                    | (0 << RCC_PLLCFGR_PLLP_Pos)
+                    | ((pll_freq/FREQ_USB) << RCC_PLLCFGR_PLLQ_Pos));
+    RCC->CR |= RCC_CR_PLLON;
+#endif
+}
+
+static void
 enable_clock_stm32f40x(void)
 {
 #if CONFIG_MACH_STM32F405 || CONFIG_MACH_STM32F407
@@ -194,7 +216,9 @@ static void
 clock_setup(void)
 {
     // Configure and enable PLL
-    if (CONFIG_MACH_STM32F405 || CONFIG_MACH_STM32F407)
+    if (CONFIG_MACH_STM32F207)
+        enable_clock_stm32f20x();
+    else if (CONFIG_MACH_STM32F405 || CONFIG_MACH_STM32F407)
         enable_clock_stm32f40x();
     else
         enable_clock_stm32f446();