AP_HAL_ChibiOS: External flash optimizations (H750 etc.) backport to 4.4

libraries/AP_HAL_ChibiOS/hwdef/common/chibios_board.mk

@@ -250,6 +250,10 @@ endif
 # Define ASM defines here
 UADEFS =
 
+ifeq ($(COPY_VECTORS_TO_RAM),yes)
+ UADEFS += -DCRT0_INIT_VECTORS=1
+endif
+
 # List all user directories here
 UINCDIR =
 

libraries/AP_HAL_ChibiOS/hwdef/common/common_extf.ld

@@ -20,16 +20,16 @@
 */
 
 /* RAM region to be used for fast code. */
-REGION_ALIAS("FASTCODE_RAM", ram1)
+REGION_ALIAS("FASTCODE_RAM", flashram)
 
 /* stack areas are configured to be in AXI RAM (ram1) to ensure the SSBL will load the image */
 /* RAM region to be used for Main stack. This stack accommodates the processing
    of all exceptions and interrupts*/
-REGION_ALIAS("MAIN_STACK_RAM", ram1);
+REGION_ALIAS("MAIN_STACK_RAM", flashram);
 
 /* RAM region to be used for the process stack. This is the stack used by
    the main() function.*/
-REGION_ALIAS("PROCESS_STACK_RAM", ram1);
+REGION_ALIAS("PROCESS_STACK_RAM", flashram);
 
 /* RAM region to be used for data segment.*/
 REGION_ALIAS("DATA_RAM", ram0);
@@ -45,19 +45,19 @@ __ram0_size__           = LENGTH(ram0);
 __ram0_end__            = __ram0_start__ + __ram0_size__;
 
 /* AXI */
-__ram1_start__          = ORIGIN(ram1);
-__ram1_size__           = LENGTH(ram1);
+__ram1_start__          = ORIGIN(flashram);
+__ram1_size__           = LENGTH(flashram);
 __ram1_end__            = __ram1_start__ + __ram1_size__;
 
 /* DTCM */
-__ram2_start__          = ORIGIN(ram2);
-__ram2_size__           = LENGTH(ram2);
+__ram2_start__          = ORIGIN(dataram);
+__ram2_size__           = LENGTH(dataram);
 __ram2_end__            = __ram2_start__ + __ram2_size__;
 
 /* ITCM */
-__instram_start__      = ORIGIN(instram);
-__instram_size__       = LENGTH(instram);
-__instram_end__        = __instram_start__ + __instram_size__;
+__ram3_start__          = ORIGIN(instram);
+__ram3_size__           = LENGTH(instram);
+__ram3_end__            = __ram3_start__ + __ram3_size__;
 
 ENTRY(Reset_Handler)
 
@@ -66,10 +66,14 @@ SECTIONS
     . = 0;
     _text = .;
 
-    startup : ALIGN(16) SUBALIGN(16)
+    /* Vector table: copied to RAM by startup script */
+    vectors : ALIGN(1024) SUBALIGN(16)
     {
+        __textvectors_base__ = LOADADDR(vectors);
+        __vectors_base__ = .;
         KEEP(*(.vectors))
-    } > default_flash
+        __vectors_end__ = .;
+    } > dataram AT > default_flash
 
     constructors : ALIGN(4) SUBALIGN(4)
     {
@@ -91,8 +95,8 @@ SECTIONS
     .fastramfunc : ALIGN(4) SUBALIGN(4)
     {
         . = ALIGN(4);
-        __instram_init_text__ = LOADADDR(.fastramfunc);
-        __instram_init__ = .;
+        __ram3_init_text__ = LOADADDR(.fastramfunc);
+        __ram3_init__ = .;
         /* ChibiOS won't boot unless these are excluded */
         EXCLUDE_FILE (*vectors.o *crt0_v7m.o *crt1.o)
         /* performance critical sections of ChibiOS */
@@ -119,9 +123,19 @@ SECTIONS
         *libstdc++_nano.a:(.text* .rodata*)*/
         *(.fastramfunc)
         . = ALIGN(4);
-        __instram_end__ = .;
     } > instram AT > default_flash
 
+    .ram3 (NOLOAD) : ALIGN(4)
+    {
+        . = ALIGN(4);
+        __ram3_clear__ = .;
+        . = ALIGN(4);
+        __ram3_noinit__ = .;
+        . = ALIGN(4);
+        __ram3_free__ = .;
+        . = ALIGN(4);
+    } > instram
+
     /* FLASH_RAM area is primarily used for RAM-based code and data, 256k allocation on H7 */
     .ramfunc : ALIGN(4) SUBALIGN(4)
     {
@@ -162,7 +176,7 @@ SECTIONS
         Tools/CPUInfo/EKF_Maths.*(.text* .rodata*)*/
         *(.ramfunc*)
         . = ALIGN(4);
-    } > ram1 AT > default_flash
+    } > flashram AT > default_flash
 
     .ram1 (NOLOAD) : ALIGN(4)
     {
@@ -173,7 +187,7 @@ SECTIONS
         *(.ram1*)
         . = ALIGN(4);
         __ram1_free__ = .;
-    } > ram1
+    } > flashram
 
     /* DATA_RAM area is DTCM primarily used for RAM-based data, e.g. vtables */
     .ramdata : ALIGN(4)
@@ -201,7 +215,7 @@ SECTIONS
         *libm.a:*(.rodata*)
         *(.ramdata*)
         . = ALIGN(4);
-    } > ram2 AT > default_flash
+    } > dataram AT > default_flash
 
     .ram2 (NOLOAD) : ALIGN(4)
     {
@@ -212,7 +226,7 @@ SECTIONS
         *(.ram2*)
         . = ALIGN(4);
         __ram2_free__ = .;
-    } > ram2
+    } > dataram
 
     .text : ALIGN(4) SUBALIGN(4)
     {