From ef39f2d9cac6fc50b1bbae9d16da371649dfa6e2 Mon Sep 17 00:00:00 2001
From: Dave Hylands <dhylands@gmail.com>
Date: Thu, 13 Mar 2014 14:40:49 -0700
Subject: [PATCH] Cleanup systick for stmhal

---
 stmhal/Makefile           |  7 -------
 stmhal/stm32f4xx_it.c     |  2 --
 stmhal/system_stm32f4xx.c |  5 +++++
 stmhal/systick.c          | 12 +++---------
 4 files changed, 8 insertions(+), 18 deletions(-)

diff --git a/stmhal/Makefile b/stmhal/Makefile
index f53887b746..5ec7728083 100644
--- a/stmhal/Makefile
+++ b/stmhal/Makefile
@@ -19,7 +19,6 @@ CROSS_COMPILE = arm-none-eabi-
 
 INC =  -I.
 INC += -I$(PY_SRC)
-INC += -I$(CMSIS_DIR)
 INC += -I$(CMSIS_DIR)/inc
 INC += -I$(CMSIS_DIR)/devinc
 INC += -I$(HAL_DIR)/inc
@@ -32,7 +31,6 @@ INC += -I$(HAL_DIR)/inc
 CFLAGS_CORTEX_M4 = -mthumb -mtune=cortex-m4 -mabi=aapcs-linux -mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=hard -fsingle-precision-constant -Wdouble-promotion
 CFLAGS = $(INC) -Wall -Werror -ansi -std=gnu99 $(CFLAGS_CORTEX_M4) $(COPT)
 
-BOARD = STM32F4DISC
 BOARD ?= PYBOARD4
 ifeq ($(wildcard boards/$(BOARD)/.),)
 $(error Invalid BOARD specified)
@@ -226,11 +224,6 @@ GEN_PINS_HDR = $(BUILD)/pins.h
 # which source files might need it.
 $(OBJ): | $(BUILD)/pins.h
 
-# temp hack
-$(PY_BUILD):
-	mkdir -p $@
-$(OBJ): | $(PY_BUILD) $(PY_BUILD)/qstrdefs.generated.h
-
 # Use a pattern rule here so that make will only call make-pins.py once to make
 # both pins_$(BOARD).c and pins.h
 $(BUILD)/%_$(BOARD).c $(BUILD)/%.h: boards/$(BOARD)/%.csv $(MAKE_PINS) $(AF_FILE) $(PREFIX_FILE)
diff --git a/stmhal/stm32f4xx_it.c b/stmhal/stm32f4xx_it.c
index 61c4b7172e..96b12bfe4a 100644
--- a/stmhal/stm32f4xx_it.c
+++ b/stmhal/stm32f4xx_it.c
@@ -151,7 +151,6 @@ void PendSV_Handler(void)
 {
 }
 
-#if 0 // defined in systick.c
 /**
   * @brief  This function handles SysTick Handler.
   * @param  None
@@ -161,7 +160,6 @@ void SysTick_Handler(void)
 {
   HAL_IncTick();
 }
-#endif
 
 /******************************************************************************/
 /*                 STM32F4xx Peripherals Interrupt Handlers                   */
diff --git a/stmhal/system_stm32f4xx.c b/stmhal/system_stm32f4xx.c
index 8d806041c1..4e5490db56 100644
--- a/stmhal/system_stm32f4xx.c
+++ b/stmhal/system_stm32f4xx.c
@@ -316,6 +316,11 @@ void SystemClock_Config(void)
   {
     __fatal_error("HAL_RCC_ClockConfig");
   }
+
+  // SysTick_Config (called from HL_RCC_ClockConfig) sets the SysTick_IRQn to
+  // be the lowest priority, but we want it to be the highest priority, so fix
+  // things here.
+  HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
 }
 
 /**
diff --git a/stmhal/systick.c b/stmhal/systick.c
index 55c22dab01..eda39c7888 100644
--- a/stmhal/systick.c
+++ b/stmhal/systick.c
@@ -5,16 +5,10 @@
 void sys_tick_init(void) {
     // SysTick_Config is now called from HAL_RCC_ClockConfig, which is called
     // from SystemClock_Config
-    HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0); // make it highest priority
-}
 
-// called on SysTick interrupt
-void SysTick_Handler(void) {
-    HAL_IncTick();
-    HAL_SYSTICK_IRQHandler();
-    // hack!
-    //void audio_drain(void);
-    //audio_drain();
+    // SysTick_Config sets the SysTick_IRQn to be the lowest priority, but
+    // we want it to be the highest priority, so fix things here.
+    HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
 }
 
 void sys_tick_delay_ms(uint32_t delay_ms) {