[ion] Fix reset jump address accross platforms

ion/src/device/n0100/flash.ld

@@ -30,7 +30,7 @@ SECTIONS {
      * We're generating the ISR vector table in code because it's very
      * convenient: using function pointers, we can easily point to the service
      * routine for each interrupt. */
-   _isr_start = .;
+   _jump_reset_address = .;
     KEEP(*(.isr_vector_table))
   } >FLASH
 

ion/src/device/n0100/ram.ld

@@ -20,10 +20,10 @@ MEMORY {
  * overwritten (for instance, vtables that live in the .rodata section). */
 
 STACK_SIZE = 32K;
+_jump_reset_address = 0x08000000;
 
 SECTIONS {
   .isr_vector_table ORIGIN(RAM_BUFFER) : {
-    _isr_start = .;
     KEEP(*(.isr_vector_table))
   } >RAM_BUFFER
 

ion/src/device/n0100/usb/dfu.ld

@@ -27,7 +27,7 @@ MEMORY {
 
 /* The DFU needs to know to which address it should jump to after a leave
  * command. This address is used in Ion::Device::Reset::jump(). */
-_isr_start = 0x08000000;
+_jump_reset_address = 0x08000000;
 
 SECTIONS {
   .text : {

ion/src/device/n0200/flash.ld

@@ -38,7 +38,7 @@ SECTIONS {
      * We're generating the ISR vector table in code because it's very
      * convenient: using function pointers, we can easily point to the service
      * routine for each interrupt. */
-   _isr_start = .;
+   _jump_reset_address = .;
     KEEP(*(.isr_vector_table))
   } >INTERNAL_FLASH
 

ion/src/device/n0200/internal_flash.ld

@@ -22,7 +22,7 @@ SECTIONS {
      * We're generating the ISR vector table in code because it's very
      * convenient: using function pointers, we can easily point to the service
      * routine for each interrupt. */
-   _isr_start = .;
+   _jump_reset_address = .;
     KEEP(*(.isr_vector_table))
   } >INTERNAL_FLASH
 

ion/src/device/n0200/ram.ld

@@ -0,0 +1,81 @@
+/* Create a firmware that runs from RAM.
+ * Caution: ST's bootloader uses some RAM, so we want to stay off of that memory
+ * region. Per AN2606, sections 31.1 and 36.1, it's using 16Kbytes form address
+ * 0x20000000. We'll try to play safe and avoid the first 32KB of RAM.
+ *
+ * This is used to:
+ *  - Flash faster. Flashing using ST's ROMed DFU bootloader is reliable but
+ *  very slow. To make flashing faster, we can leverage ST's bootloader to copy
+ *  a small "flasher" in RAM, and run it from there.
+ *  - Run the bench software from the RAM. */
+
+MEMORY {
+  RAM_BUFFER (rw) : ORIGIN = 0x20000000 + 32K, LENGTH = 256K - 32K
+}
+
+/* The stack is quite large: we put it equal to Epsilon's.
+ * Indeed, when building the flasher, we're making the USB::Calculator object
+ * live on the stack, and it's quite large (about 4K just for this single
+ * object). Using a stack too small would result in some memory being
+ * overwritten (for instance, vtables that live in the .rodata section). */
+
+STACK_SIZE = 32K;
+_jump_reset_address = 0x00200000;
+
+SECTIONS {
+  .isr_vector_table ORIGIN(RAM_BUFFER) : {
+    KEEP(*(.isr_vector_table))
+  } >RAM_BUFFER
+
+  .text : {
+    . = ALIGN(4);
+    *(.text)
+    *(.text.*)
+  } >RAM_BUFFER
+
+  .init_array : {
+    . = ALIGN(4);
+    _init_array_start = .;
+    KEEP (*(.init_array*))
+    _init_array_end = .;
+  } >RAM_BUFFER
+
+  .rodata : {
+    . = ALIGN(4);
+    *(.rodata)
+    *(.rodata.*)
+  } >RAM_BUFFER
+
+  .data : {
+    . = ALIGN(4);
+    *(.data)
+    *(.data.*)
+  } >RAM_BUFFER
+
+  .bss : {
+    . = ALIGN(4);
+    _bss_section_start_ram = .;
+    *(.bss)
+    *(.bss.*)
+    *(COMMON)
+    _bss_section_end_ram = .;
+  } >RAM_BUFFER
+
+  .stack : {
+    . = ALIGN(8);
+    _stack_end = .;
+    . += (STACK_SIZE - 8);
+    . = ALIGN(8);
+    _stack_start = .;
+  } >RAM_BUFFER
+
+  .phony : {
+    /* We won't do dynamic memory allocation */
+    _heap_start = .;
+    _heap_end = .;
+    /* Effectively bypass copying .data to RAM */
+    _data_section_start_flash = .;
+    _data_section_start_ram = .;
+    _data_section_end_ram = .;
+  } >RAM_BUFFER
+}

ion/src/device/n0200/usb/dfu.ld

@@ -27,7 +27,7 @@ MEMORY {
 
 /* The DFU needs to know to which address it should jump to after a leave
  * command. This address is used in Ion::Device::Reset::jump(). */
-_isr_start = 0x00200000;
+_jump_reset_address = 0x00200000;
 
 SECTIONS {
   .text : {

ion/src/device/shared/drivers/reset.cpp

@@ -4,7 +4,7 @@
 #include <drivers/board.h>
 #include <drivers/external_flash.h>
 
-extern void * _isr_start;
+extern void * _jump_reset_address;
 
 namespace Ion {
 namespace Device {
@@ -30,7 +30,7 @@ void jump() {
    * real reset would. These operations should be made at once, otherwise the C
    * compiler might emit some instructions that modify the stack inbetween. */
 
-  uint32_t * stackPointerAddress = reinterpret_cast<uint32_t *>(&_isr_start);
+  uint32_t * stackPointerAddress = reinterpret_cast<uint32_t *>(&_jump_reset_address);
   uint32_t * resetHandlerAddress = stackPointerAddress + 1;
 
   asm volatile (

ion/test/external_flash_tests.ld

@@ -31,7 +31,7 @@ SECTIONS {
      * We're generating the ISR vector table in code because it's very
      * convenient: using function pointers, we can easily point to the service
      * routine for each interrupt. */
-   _isr_start = .;
+   _jump_reset_address = .;
     KEEP(*(.isr_vector_table))
   } >INTERNAL_FLASH
 

scripts/targets.device.mak

@@ -54,7 +54,7 @@ openocd:
 # fully filled
 ifeq ($(EPSILON_USB_DFU_XIP)$(EPSILON_DEVICE_BENCH),10)
 $(BUILD_DIR)/ion/src/$(PLATFORM)/shared/usb/flasher.o: SFLAGS += $(ION_DEVICE_SFLAGS)
-$(BUILD_DIR)/flasher.$(EXE): LDSCRIPT = ion/src/$(PLATFORM)/shared/ram.ld
+$(BUILD_DIR)/flasher.$(EXE): LDSCRIPT = ion/src/$(PLATFORM)/$(MODEL)/ram.ld
 $(BUILD_DIR)/flasher.$(EXE): $(objs) $(BUILD_DIR)/ion/src/$(PLATFORM)/shared/usb/flasher.o
 else
 $(BUILD_DIR)/flasher.$(EXE):
@@ -63,7 +63,7 @@ endif
 
 #TODO Do not build all apps... Put elsewhere?
 ifeq ($(EPSILON_USB_DFU_XIP)$(EPSILON_DEVICE_BENCH),11)
-$(BUILD_DIR)/benchRAM.$(EXE): LDSCRIPT = ion/src/$(PLATFORM)/shared/ram.ld
+$(BUILD_DIR)/benchRAM.$(EXE): LDSCRIPT = ion/src/$(PLATFORM)/$(MODEL)/ram.ld
 $(BUILD_DIR)/benchRAM.$(EXE): $(objs) $(call object_for,$(bench_src))
 else
 $(BUILD_DIR)/benchRAM.$(EXE):