rp2040: Support CanBoot as bootloader

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

3 files changed, 41 insertions, 14 deletions

diff --git a/src/rp2040/Kconfig b/src/rp2040/Kconfig
index 148222d7e..69b1cd58e 100644
--- a/src/rp2040/Kconfig
+++ b/src/rp2040/Kconfig
@@ -47,17 +47,32 @@ config STACK_SIZE
     int
     default 512
 
-config FLASH_START
-    hex
-    default 0x10000100
-
 
 ######################################################################
 # Bootloader options
 ######################################################################
 
+config RP2040_HAVE_STAGE2
+    bool
+config RP2040_HAVE_BOOTLOADER
+    bool
+    default y if !RP2040_HAVE_STAGE2
+
+choice
+    prompt "Bootloader offset"
+    config RP2040_FLASH_START_0100
+        bool "No bootloader"
+        select RP2040_HAVE_STAGE2
+    config RP2040_FLASH_START_4000
+        bool "16KiB bootloader"
+endchoice
+config FLASH_START
+    hex
+    default 0x10004000 if RP2040_FLASH_START_4000
+    default 0x10000100
+
 choice
-    prompt "Flash chip" if LOW_LEVEL_OPTIONS
+    prompt "Flash chip" if LOW_LEVEL_OPTIONS && RP2040_HAVE_STAGE2
     config RP2040_FLASH_W25Q080
         bool "W25Q080 with CLKDIV 2"
     config RP2040_FLASH_GENERIC_03
diff --git a/src/rp2040/Makefile b/src/rp2040/Makefile
index 5bb572fb2..47954c9a3 100644
--- a/src/rp2040/Makefile
+++ b/src/rp2040/Makefile
@@ -8,10 +8,6 @@ dirs-y += src/rp2040 src/generic lib/rp2040/elf2uf2 lib/fast-hash lib/can2040
 CFLAGS += -mcpu=cortex-m0plus -mthumb -Ilib/cmsis-core
 CFLAGS += -Ilib/rp2040 -Ilib/rp2040/cmsis_include -Ilib/fast-hash -Ilib/can2040
 
-CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs
-CFLAGS_klipper.elf += -T $(OUT)src/rp2040/rp2040_link.ld
-$(OUT)klipper.elf: $(OUT)stage2.o $(OUT)src/rp2040/rp2040_link.ld
-
 # Add source files
 src-y += rp2040/main.c rp2040/gpio.c rp2040/adc.c generic/crc16_ccitt.c
 src-y += generic/armcm_boot.c generic/armcm_irq.c generic/armcm_reset.c
@@ -38,11 +34,8 @@ $(OUT)stage2.o: lib/rp2040/boot_stage2/$(STAGE2_FILE) $(OUT)autoconf.h
 	$(Q)$(OBJCOPY) -O binary $(OUT)stage2raw.o $(OUT)stage2raw.bin
 	$(Q)lib/rp2040/boot_stage2/pad_checksum -s 0xffffffff $(OUT)stage2raw.bin $(OUT)stage2.S
 	$(Q)$(CC) $(CFLAGS) -c $(OUT)stage2.S -o $(OUT)stage2.o
-OBJS_klipper.elf += $(OUT)stage2.o
-
-# Binary output file rules
-target-y += $(OUT)klipper.uf2
 
+# Binary output file rules when using stage2
 $(OUT)lib/rp2040/elf2uf2/elf2uf2: lib/rp2040/elf2uf2/main.cpp
 	@echo "  Building $@"
 	$(Q)g++ -g -O -Ilib/rp2040 $< -o $@
@@ -51,11 +44,28 @@ $(OUT)klipper.uf2: $(OUT)klipper.elf $(OUT)lib/rp2040/elf2uf2/elf2uf2
 	@echo "  Creating uf2 file $@"
 	$(Q)$(OUT)lib/rp2040/elf2uf2/elf2uf2 $< $@
 
+target-$(CONFIG_RP2040_HAVE_STAGE2) += $(OUT)klipper.uf2
+rplink-$(CONFIG_RP2040_HAVE_STAGE2) := $(OUT)src/rp2040/rp2040_link.ld
+stage2-$(CONFIG_RP2040_HAVE_STAGE2) := $(OUT)stage2.o
+
+# rp2040 building when using a bootloader
+$(OUT)klipper.bin: $(OUT)klipper.elf
+	@echo "  Creating bin file $@"
+	$(Q)$(OBJCOPY) -O binary $< $@
+
+target-$(CONFIG_RP2040_HAVE_BOOTLOADER) += $(OUT)klipper.bin
+rplink-$(CONFIG_RP2040_HAVE_BOOTLOADER) := $(OUT)src/generic/armcm_link.ld
+
+# Set klipper.elf linker rules
+CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs -T $(rplink-y)
+OBJS_klipper.elf += $(stage2-y)
+$(OUT)klipper.elf: $(stage2-y) $(rplink-y)
+
+# Flash rules
 lib/rp2040_flash/rp2040_flash:
 	@echo "  Building rp2040_flash"
 	$(Q)make -C lib/rp2040_flash rp2040_flash
 
-# Flash rules
 flash: $(OUT)klipper.uf2 lib/rp2040_flash/rp2040_flash
 	@echo "  Flashing $< to $(FLASH_DEVICE)"
 	$(Q)$(PYTHON) ./scripts/flash_usb.py -t $(CONFIG_MCU) -d "$(FLASH_DEVICE)" $(if $(NOSUDO),--no-sudo) $(OUT)klipper.uf2
diff --git a/src/rp2040/main.c b/src/rp2040/main.c
index 462e69c69..eac3a0b93 100644
--- a/src/rp2040/main.c
+++ b/src/rp2040/main.c
@@ -6,6 +6,7 @@
 
 #include <stdint.h> // uint32_t
 #include "board/misc.h" // bootloader_request
+#include "generic/armcm_reset.h" // try_request_canboot
 #include "hardware/structs/clocks.h" // clock_hw_t
 #include "hardware/structs/pll.h" // pll_hw_t
 #include "hardware/structs/resets.h" // sio_hw
@@ -45,6 +46,7 @@ DECL_INIT(watchdog_init);
 void
 bootloader_request(void)
 {
+    try_request_canboot();
     // Use the bootrom-provided code to reset into BOOTSEL mode
     reset_to_usb_boot(0, 0);
 }