From d13ec1241cd97542694190c6496087b8725e399c Mon Sep 17 00:00:00 2001
From: Renaud Fivet <renaud.fivet@gmail.com>
Date: Fri, 18 Jun 2021 13:24:54 +0800
Subject: [PATCH] In RAM execution using all RAM when loading via SWD.

---
 Makefile      | 38 ++++++++++++++++++++++++++++++--------
 generic.ld    |  6 ++++--
 startup.ram.c |  4 ++--
 3 files changed, 36 insertions(+), 12 deletions(-)

diff --git a/Makefile b/Makefile
index 3b7bb48..1571ce9 100644
--- a/Makefile
+++ b/Makefile
@@ -41,23 +41,41 @@ SIZE    = $(BINPFX)size
 
 PROJECT = f030f4
 
-# In RAM Execution
+### Memory Models
+
+# In RAM Execution, load and start by USART bootloader
 # Bootloader uses first 2K of RAM, execution from bootloader
 #FLASHSTART = 0x20000800
 #FLASHSIZE  = 2K
 #RAMSTART   = 0x20000000
 #RAMSIZE    = 2K
 
+# In RAM Execution, load and start via SWD
+# 4K RAM available, execution via SWD
+#FLASHSTART = 0x20000000
+#FLASHSIZE  = 3K
+#RAMSTART   = 0x20000C00
+#RAMSIZE    = 1K
+
 # In Flash Execution
-# if FLASHSTART is not at beginning of FLASH: execution from bootloader
+# if FLASHSTART is not at beginning of FLASH: execution via bootloader or SWD
 FLASHSTART = 0x08000000
 FLASHSIZE  = 16K
 RAMSTART   = 0x20000000
 RAMSIZE    = 4K
 
 # ISR vector copied and mapped to RAM if FLASHSTART != 0x08000000
-ifneq ($(FLASHSTART),0x08000000)
- RAMISRV := 1
+ifdef FLASHSTART
+ ifneq ($(FLASHSTART),0x08000000)
+  ifeq ($(FLASHSTART),0x20000000)
+   # Map isr vector in RAM
+   RAMISRV := 1
+  else
+   # Copy and map isr vector in RAM
+   RAMISRV := 2
+  endif
+ endif
+ FNAMLOC = .$(FLASHSTART)
 endif
 
 #SRCS = boot.c
@@ -90,8 +108,10 @@ WARNINGS=-pedantic -Wall -Wextra -Wstrict-prototypes -Wno-unused-parameter
 CFLAGS = $(CPU) -g $(WARNINGS) -Os $(CDEFINES)
 
 LD_SCRIPT = generic.ld
-LDOPTS  =--defsym FLASHSTART=$(FLASHSTART) --defsym FLASHSIZE=$(FLASHSIZE)
-LDOPTS +=--defsym RAMSTART=$(RAMSTART) --defsym RAMSIZE=$(RAMSIZE)
+ifdef FLASHSTART
+ LDOPTS  =--defsym FLASHSTART=$(FLASHSTART) --defsym FLASHSIZE=$(FLASHSIZE)
+ LDOPTS +=--defsym RAMSTART=$(RAMSTART) --defsym RAMSIZE=$(RAMSIZE)
+endif
 LDOPTS +=-Map=$(subst .elf,.map,$@) -cref --print-memory-usage
 comma :=,
 space :=$() # one space before the comment
@@ -101,7 +121,7 @@ LDFLAGS =-Wl,$(subst $(space),$(comma),$(LDOPTS))
 
 .PHONY: clean all version
 
-all: $(PROJECT).hex $(PROJECT).$(FLASHSTART).bin
+all: $(PROJECT).hex $(PROJECT)$(FNAMLOC).bin
 
 version:
 	@echo make $(MAKE_VERSION) $(MAKE_HOST)
@@ -125,11 +145,13 @@ cstartup.elf: cstartup.o
 	$(SIZE) -G $@
 	$(OBJDUMP) -hS $@ > $(subst .elf,.lst,$@)
 
+ifdef FNAMLOC
 %.bin: %.elf
 	@echo $@
 	$(OBJCOPY) -O binary $< $@
+endif
 
-%.$(FLASHSTART).bin: %.elf
+%$(FNAMLOC).bin: %.elf
 	@echo $@
 	$(OBJCOPY) -O binary $< $@
 
diff --git a/generic.ld b/generic.ld
index e099913..fc77aa0 100644
--- a/generic.ld
+++ b/generic.ld
@@ -11,8 +11,10 @@
 MEMORY
 {
 /* FLASH means code, read only data and data initialization */
-	FLASH (rx)  : ORIGIN = FLASHSTART, LENGTH =  FLASHSIZE
-	RAM   (rwx) : ORIGIN = RAMSTART,   LENGTH =  RAMSIZE
+	FLASH (rx) : ORIGIN = DEFINED(FLASHSTART) ? FLASHSTART : 0x08000000,
+		LENGTH =  DEFINED(FLASHSIZE) ? FLASHSIZE : 16K
+	RAM  (rwx) : ORIGIN = DEFINED(RAMSTART) ? RAMSTART : 0x20000000,
+		LENGTH =  DEFINED(RAMSIZE) ? RAMSIZE : 4K
 }
 
 /* Linker script to place sections and symbol values. Should be used together
diff --git a/startup.ram.c b/startup.ram.c
index d4a8c04..5bec5ef 100644
--- a/startup.ram.c
+++ b/startup.ram.c
@@ -110,7 +110,7 @@ isr_p const isr_vector[ 16 + 32] __attribute__((section(".isr_vector"))) = {
     USB_Handler
 } ;
 
-#if RAMISRV
+#if RAMISRV == 2
 # define ISRV_SIZE (sizeof isr_vector / sizeof *isr_vector)
 isr_p ram_vector[ ISRV_SIZE] __attribute__((section(".ram_vector"))) ;
 #endif
@@ -121,7 +121,7 @@ void Reset_Handler( void) {
     const long  *f ;    /* from, source constant data from FLASH */
     long    *t ;        /* to, destination in RAM */
 
-#if RAMISRV
+#if RAMISRV == 2
 /* Copy isr vector to beginning of RAM */
     for( unsigned i = 0 ; i < ISRV_SIZE ; i++)
         ram_vector[ i] = isr_vector[ i] ;