SCB_EnableDCache() is required for rt1011

hw/bsp/imxrt/family.c

@@ -107,6 +107,13 @@ static void init_usb_phy(uint8_t usb_id) {
 }
 
 void board_init(void) {
+// make sure the dcache is on.
+#if defined(__DCACHE_PRESENT) && __DCACHE_PRESENT
+  if (SCB_CCR_DC_Msk != (SCB_CCR_DC_Msk & SCB->CCR)) {
+    SCB_EnableDCache();
+  }
+#endif
+
   BOARD_InitBootPins();
   BOARD_BootClockRUN();
   SystemCoreClockUpdate();
@@ -237,21 +244,9 @@ uint32_t board_millis(void) {
 }
 #endif
 
-
-#ifndef __ICCARM__
-// Implement _start() since we use linker flag '-nostartfiles'.
-// Requires defined __STARTUP_CLEAR_BSS,
-extern int main(void);
-TU_ATTR_UNUSED void _start(void) {
-  // called by startup code
-  main();
-  while (1) {}
-}
-
 #ifdef __clang__
 void _exit(int __status) {
   (void) __status;
   while (1) {}
 }
 #endif
-#endif

hw/bsp/imxrt/family.cmake

@@ -44,7 +44,6 @@ function(family_add_board BOARD_TARGET)
     ${SDK_DIR}/drivers/lpuart/fsl_lpuart.c
     ${SDK_DIR}/drivers/ocotp/fsl_ocotp.c
     ${SDK_DIR}/devices/${MCU_VARIANT}/system_${MCU_VARIANT_WITH_CORE}.c
-    ${SDK_DIR}/devices/${MCU_VARIANT}/xip/fsl_flexspi_nor_boot.c
     ${SDK_DIR}/devices/${MCU_VARIANT}/drivers/fsl_clock.c
     )
 
@@ -56,11 +55,6 @@ function(family_add_board BOARD_TARGET)
     endif()
   endforeach()
 
-  target_compile_definitions(${BOARD_TARGET} PUBLIC
-    __STARTUP_CLEAR_BSS
-    [=[CFG_TUSB_MEM_SECTION=__attribute__((section("NonCacheable")))]=]
-    )
-
   if (NOT M4 STREQUAL "1")
     target_compile_definitions(${BOARD_TARGET} PUBLIC
       XIP_EXTERNAL_FLASH=1
@@ -74,7 +68,6 @@ function(family_add_board BOARD_TARGET)
     ${CMSIS_DIR}/CMSIS/Core/Include
     ${SDK_DIR}/devices/${MCU_VARIANT}
     ${SDK_DIR}/devices/${MCU_VARIANT}/drivers
-    #${SDK_DIR}/drivers/adc_12b1msps_sar
     ${SDK_DIR}/drivers/common
     ${SDK_DIR}/drivers/igpio
     ${SDK_DIR}/drivers/lpspi
@@ -92,12 +85,13 @@ function(family_configure_example TARGET RTOS)
   family_configure_common(${TARGET} ${RTOS})
   family_add_tinyusb(${TARGET} OPT_MCU_MIMXRT1XXX)
 
-  target_sources(${TARGET} PUBLIC
+  target_sources(${TARGET} PRIVATE
     ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/family.c
     ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/../board.c
     ${TOP}/src/portable/chipidea/ci_hs/dcd_ci_hs.c
     ${TOP}/src/portable/chipidea/ci_hs/hcd_ci_hs.c
     ${TOP}/src/portable/ehci/ehci.c
+    ${SDK_DIR}/devices/${MCU_VARIANT}/xip/fsl_flexspi_nor_boot.c
     ${STARTUP_FILE_${CMAKE_C_COMPILER_ID}}
     )
   target_include_directories(${TARGET} PUBLIC
@@ -105,26 +99,22 @@ function(family_configure_example TARGET RTOS)
     ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/../../
     ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/boards/${BOARD}
     )
+  target_compile_definitions(${TARGET} PUBLIC
+    __START=main # required with -nostartfiles
+    __STARTUP_CLEAR_BSS
+    [=[CFG_TUSB_MEM_SECTION=__attribute__((section("NonCacheable")))]=]
+    )
 
   if (CMAKE_C_COMPILER_ID STREQUAL "GNU")
     target_link_options(${TARGET} PUBLIC
       "LINKER:--script=${LD_FILE_GNU}"
       -nostartfiles
       --specs=nosys.specs --specs=nano.specs
-      # force linker to look for these symbols
-      -Wl,-uimage_vector_table
-      -Wl,-ug_boot_data
       )
   elseif (CMAKE_C_COMPILER_ID STREQUAL "Clang")
-    target_link_options(${TARGET} PUBLIC
-      "LINKER:--script=${LD_FILE_GNU}"
-      -Wl,-uimage_vector_table
-      -Wl,-ug_boot_data
-      )
+    target_link_options(${TARGET} PRIVATE "LINKER:--script=${LD_FILE_GNU}")
   elseif (CMAKE_C_COMPILER_ID STREQUAL "IAR")
-    target_link_options(${TARGET} PUBLIC
-      "LINKER:--config=${LD_FILE_IAR}"
-      )
+    target_link_options(${TARGET} PRIVATE "LINKER:--config=${LD_FILE_IAR}")
   endif ()
 
   if (CMAKE_C_COMPILER_ID STREQUAL "GNU" OR CMAKE_C_COMPILER_ID STREQUAL "Clang")

hw/bsp/imxrt/family.mk

@@ -8,6 +8,7 @@ MCU_VARIANT_WITH_CORE = ${MCU_VARIANT}${MCU_CORE}
 MCU_DIR = $(SDK_DIR)/devices/$(MCU_VARIANT)
 
 CFLAGS += \
+	-D__START=main \
   -D__STARTUP_CLEAR_BSS \
   -DCFG_TUSB_MCU=OPT_MCU_MIMXRT1XXX \
   -DCFG_TUSB_MEM_SECTION='__attribute__((section("NonCacheable")))' \