diff --git a/main.c b/main.c
index eefc081f33cc8..45b7af2725435 100644
--- a/main.c
+++ b/main.c
@@ -30,6 +30,7 @@
 #include "supervisor/cpu.h"
 #include "supervisor/filesystem.h"
 #include "supervisor/port.h"
+#include "supervisor/shared/cpu_regs.h"
 #include "supervisor/shared/reload.h"
 #include "supervisor/shared/safe_mode.h"
 #include "supervisor/shared/serial.h"
@@ -1135,9 +1136,14 @@ int __attribute__((used)) main(void) {
 void gc_collect(void) {
     gc_collect_start();
 
-    mp_uint_t regs[10];
+    // Load register values onto the stack. They get collected below with the rest of the stack.
+    size_t regs[SAVED_REGISTER_COUNT];
     mp_uint_t sp = cpu_get_regs_and_sp(regs);
 
+    // This naively collects all object references from an approximate stack
+    // range.
+    gc_collect_root((void **)sp, ((mp_uint_t)port_stack_get_top() - sp) / sizeof(mp_uint_t));
+
     // This collects root pointers from the VFS mount table. Some of them may
     // have lost their references in the VM even though they are mounted.
     gc_collect_root((void **)&MP_STATE_VM(vfs_mount_table), sizeof(mp_vfs_mount_t) / sizeof(mp_uint_t));
@@ -1170,9 +1176,6 @@ void gc_collect(void) {
     common_hal_wifi_gc_collect();
     #endif
 
-    // This naively collects all object references from an approximate stack
-    // range.
-    gc_collect_root((void **)sp, ((mp_uint_t)port_stack_get_top() - sp) / sizeof(mp_uint_t));
     gc_collect_end();
 }
 
diff --git a/ports/analog/Makefile b/ports/analog/Makefile
index 8e4cf3bc91728..08b245c5897e3 100644
--- a/ports/analog/Makefile
+++ b/ports/analog/Makefile
@@ -138,8 +138,8 @@ LINKERFILE = linking/$(MCU_VARIANT_LOWER)_cktpy.ld
 LDFLAGS += -nostartfiles -specs=nano.specs
 endif
 
-SRC_S += supervisor/cpu.s \
-			$(STARTUPFILE)
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
+SRC_S += $(STARTUPFILE)
 
 # Needed to compile some MAX32 headers
 CFLAGS += 	-D$(MCU_VARIANT_UPPER) \
@@ -236,6 +236,7 @@ OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_S:.s=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
 
 # List of sources for qstr extraction
diff --git a/ports/analog/supervisor/cpu.s b/ports/analog/supervisor/cpu.s
deleted file mode 100644
index 7cb8291045f14..0000000000000
--- a/ports/analog/supervisor/cpu.s
+++ /dev/null
@@ -1,34 +0,0 @@
-// This file is part of the CircuitPython project: https://circuitpython.org
-//
-// SPDX-FileCopyrightText: Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
-// SPDX-FileCopyrightText: Copyright (c) 2024 Brandon Hurst, Analog Devices, Inc
-//
-// SPDX-License-Identifier: MIT
-
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/atmel-samd/Makefile b/ports/atmel-samd/Makefile
index fa9bd923fdc4d..888729c7b7f3d 100644
--- a/ports/atmel-samd/Makefile
+++ b/ports/atmel-samd/Makefile
@@ -308,7 +308,7 @@ ifeq ($(CIRCUITPY_AUDIOBUSIO),1)
 SRC_C += peripherals/samd/i2s.c peripherals/samd/$(PERIPHERALS_CHIP_FAMILY)/i2s.c
 endif
 
-SRC_S = supervisor/$(CHIP_FAMILY)_cpu.s
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
 
 OBJ = $(PY_O) $(SUPERVISOR_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_ASF:.c=.o))
@@ -317,7 +317,7 @@ ifeq ($(INTERNAL_LIBM),1)
 OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
-OBJ += $(addprefix $(BUILD)/, $(SRC_S:.s=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
 
 QSTR_GLOBAL_REQUIREMENTS += $(HEADER_BUILD)/sdiodata.h
diff --git a/ports/atmel-samd/supervisor/samd21_cpu.s b/ports/atmel-samd/supervisor/samd21_cpu.s
deleted file mode 100755
index 741bb21358ad2..0000000000000
--- a/ports/atmel-samd/supervisor/samd21_cpu.s
+++ /dev/null
@@ -1,35 +0,0 @@
-.syntax unified
-.cpu cortex-m0
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0, #0]
-str     r5, [r0, #4]
-str     r6, [r0, #8]
-str     r7, [r0, #12]
-push {r1}
-mov     r1, r8
-str     r1, [r0, #16]
-mov     r1, r9
-str     r1, [r0, #20]
-mov     r1, r10
-str     r1, [r0, #24]
-mov     r1, r11
-str     r1, [r0, #28]
-mov     r1, r12
-str     r1, [r0, #32]
-mov     r1, r13
-str     r1, [r0, #36]
-pop {r1}
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/atmel-samd/supervisor/samd51_cpu.s b/ports/atmel-samd/supervisor/samd51_cpu.s
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/atmel-samd/supervisor/samd51_cpu.s
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/atmel-samd/supervisor/same51_cpu.s b/ports/atmel-samd/supervisor/same51_cpu.s
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/atmel-samd/supervisor/same51_cpu.s
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/atmel-samd/supervisor/same54_cpu.s b/ports/atmel-samd/supervisor/same54_cpu.s
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/atmel-samd/supervisor/same54_cpu.s
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/cxd56/Makefile b/ports/cxd56/Makefile
index ca97c33ca70ea..fdf3646c80d27 100644
--- a/ports/cxd56/Makefile
+++ b/ports/cxd56/Makefile
@@ -110,7 +110,7 @@ LDFLAGS = \
 
 CFLAGS += -DCFG_TUSB_MCU=OPT_MCU_CXD56 -DCFG_TUD_MIDI_RX_BUFSIZE=512 -DCFG_TUD_CDC_RX_BUFSIZE=1024 -DCFG_TUD_MIDI_TX_BUFSIZE=512 -DCFG_TUD_CDC_TX_BUFSIZE=1024 -DCFG_TUD_MSC_BUFSIZE=512 $(CFLAGS_MOD)
 
-SRC_S = supervisor/cpu.s
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
 
 SRC_C += \
 	background.c \
@@ -120,7 +120,7 @@ SRC_C += \
 	lib/tinyusb/src/portable/sony/cxd56/dcd_cxd56.c \
 
 OBJ = $(PY_O) $(SUPERVISOR_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
-OBJ += $(addprefix $(BUILD)/, $(SRC_S:.s=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_COMMON_HAL_SHARED_MODULE_EXPANDED:.c=.o))
 ifeq ($(INTERNAL_LIBM),1)
 OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
diff --git a/ports/cxd56/supervisor/cpu.s b/ports/cxd56/supervisor/cpu.s
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/cxd56/supervisor/cpu.s
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/espressif/Makefile b/ports/espressif/Makefile
index bdf0fd53f6876..8152fc78ee031 100644
--- a/ports/espressif/Makefile
+++ b/ports/espressif/Makefile
@@ -486,6 +486,8 @@ FROZEN_MPY_PY_FILES := $(shell find -L $(FROZEN_MPY_DIR) -type f -name '*.py')
 FROZEN_MPY_MPY_FILES := $(addprefix $(BUILD)/,$(FROZEN_MPY_PY_FILES:.py=.mpy))
 endif
 
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
+
 OBJ += $(PY_O) $(SUPERVISOR_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_COMMON_HAL_SHARED_MODULE_EXPANDED:.c=.o))
 ifeq ($(INTERNAL_LIBM),1)
@@ -493,6 +495,7 @@ OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 
 $(BUILD)/$(FATFS_DIR)/ff.o: COPT += -Os
 $(filter $(PY_BUILD)/../extmod/vfs_fat_%.o, $(PY_O)): COPT += -Os
diff --git a/ports/espressif/boards/lolin_c3_mini/mpconfigboard.mk b/ports/espressif/boards/lolin_c3_mini/mpconfigboard.mk
index 36dc38883ff39..2a8d4c97b69a7 100644
--- a/ports/espressif/boards/lolin_c3_mini/mpconfigboard.mk
+++ b/ports/espressif/boards/lolin_c3_mini/mpconfigboard.mk
@@ -9,4 +9,7 @@ CIRCUITPY_ESP_FLASH_SIZE=4MB
 
 CIRCUITPY_LEGACY_4MB_FLASH_LAYOUT = 1
 
+# Not enough flash
+CIRCUITPY_SOCKETPOOL_IPV6 = 0
+
 CIRCUITPY_ESP_USB_SERIAL_JTAG = 1
diff --git a/ports/espressif/mphalport.c b/ports/espressif/mphalport.c
index d6a7ef1bfce41..9046bbf7b102f 100644
--- a/ports/espressif/mphalport.c
+++ b/ports/espressif/mphalport.c
@@ -21,7 +21,6 @@ void IRAM_ATTR mp_hal_delay_us(mp_uint_t delay) {
 // This is provided by the esp-idf/components/xtensa/esp32s2/libhal.a binary blob.
 #ifndef CONFIG_IDF_TARGET_ARCH_RISCV
 extern void xthal_window_spill(void);
-#endif
 
 mp_uint_t cpu_get_regs_and_sp(mp_uint_t *regs) {
     // xtensa has more registers than an instruction can address. The 16 that
@@ -37,8 +36,7 @@ mp_uint_t cpu_get_regs_and_sp(mp_uint_t *regs) {
     // there is a HAL call to do it. There is a bit of a race condition here
     // because the register value could change after it's been restored but that
     // is unlikely to happen with a heap pointer while we do a GC.
-    #ifndef CONFIG_IDF_TARGET_ARCH_RISCV
     xthal_window_spill();
-    #endif
-    return (mp_uint_t)__builtin_frame_address(0);
+    return (mp_uint_t)__builtin_stack_address();
 }
+#endif
diff --git a/ports/litex/Makefile b/ports/litex/Makefile
index 688a1887959c8..bb1d88e755201 100644
--- a/ports/litex/Makefile
+++ b/ports/litex/Makefile
@@ -77,8 +77,9 @@ ifneq ($(CIRCUITPY_USB),0)
 SRC_C += lib/tinyusb/src/portable/valentyusb/eptri/dcd_eptri.c
 endif
 
-SRC_S = \
-	crt0-vexriscv.S
+SRC_S_UPPER = \
+	crt0-vexriscv.S \
+	supervisor/shared/cpu_regs.S
 
 $(BUILD)/lib/tlsf/tlsf.o: CFLAGS += -Wno-cast-align
 
@@ -93,7 +94,7 @@ ifeq ($(INTERNAL_LIBM),1)
 OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
-OBJ += $(addprefix $(BUILD)/, $(SRC_S:.S=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
 
 $(BUILD)/$(FATFS_DIR)/ff.o: COPT += -Os
diff --git a/ports/litex/mphalport.c b/ports/litex/mphalport.c
index cc74762a14f14..b94699e81e705 100644
--- a/ports/litex/mphalport.c
+++ b/ports/litex/mphalport.c
@@ -54,9 +54,3 @@ void isr(void) {
     // Decrease the "nesting count". Note: This should be going from 1 -> 0.
     nesting_count -= 1;
 }
-
-mp_uint_t cpu_get_regs_and_sp(mp_uint_t *regs) {
-    unsigned long __tmp;
-    asm volatile ("mv %0, x2" : "=r" (__tmp));
-    return __tmp;
-}
diff --git a/ports/mimxrt10xx/Makefile b/ports/mimxrt10xx/Makefile
index bbbb2479721ae..57a8beb069129 100644
--- a/ports/mimxrt10xx/Makefile
+++ b/ports/mimxrt10xx/Makefile
@@ -161,9 +161,9 @@ SRC_C += \
 
 endif
 
-SRC_S = \
+SRC_S_UPPER = \
     sdk/devices/$(CHIP_FAMILY)/gcc/startup_$(CHIP_CORE).S \
-    supervisor/cpu.S
+    supervisor/shared/cpu_regs.S
 
 OBJ = $(PY_O) $(SUPERVISOR_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_SDK:.c=.o))
@@ -173,6 +173,7 @@ OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_S:.S=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
 
 SRC_QSTR += $(SRC_C) $(SRC_SUPERVISOR) $(SRC_COMMON_HAL_SHARED_MODULE_EXPANDED) $(SRC_CIRCUITPY_COMMON)
diff --git a/ports/mimxrt10xx/supervisor/cpu.S b/ports/mimxrt10xx/supervisor/cpu.S
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/mimxrt10xx/supervisor/cpu.S
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/nordic/Makefile b/ports/nordic/Makefile
index 9633dfdd3a824..e60b4072a8d48 100755
--- a/ports/nordic/Makefile
+++ b/ports/nordic/Makefile
@@ -146,7 +146,7 @@ SRC_C += $(SRC_DCD)
 $(patsubst %.c,$(BUILD)/%.o,$(SRC_DCD)): CFLAGS += -Wno-missing-prototypes
 endif # CIRCUITPY_USB_DEVICE
 
-SRC_S = supervisor/cpu.s
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
 
 OBJ += $(PY_O) $(SUPERVISOR_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_NRFX:.c=.o))
@@ -155,7 +155,7 @@ ifeq ($(INTERNAL_LIBM),1)
 OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
-OBJ += $(addprefix $(BUILD)/, $(SRC_S:.s=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
 
 # nrfx uses undefined preprocessor variables quite casually, so we can't do
diff --git a/ports/nordic/supervisor/cpu.s b/ports/nordic/supervisor/cpu.s
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/nordic/supervisor/cpu.s
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/raspberrypi/Makefile b/ports/raspberrypi/Makefile
index e9090f5fbe24e..582c04282734c 100644
--- a/ports/raspberrypi/Makefile
+++ b/ports/raspberrypi/Makefile
@@ -660,13 +660,13 @@ else
 OBJ_MBEDTLS :=
 endif
 
-SRC_S = supervisor/$(CHIP_FAMILY)_cpu.s
 BOOT2_S_CFLAGS ?= -DPICO_FLASH_SPI_CLKDIV=4
 SRC_S_UPPER = sdk/src/rp2_common/hardware_irq/irq_handler_chain.S \
               sdk/src/rp2_common/pico_bit_ops/bit_ops_aeabi.S \
               sdk/src/rp2_common/pico_double/double_aeabi_$(DOUBLE_EABI).S \
               sdk/src/rp2_common/pico_int64_ops/pico_int64_ops_aeabi.S \
               sdk/src/rp2_common/pico_crt0/crt0.S \
+              supervisor/shared/cpu_regs.S \
               $(SRC_S_UPPER_CHIP_VARIANT)
 
 ifeq ($(CIRCUITPY_PICODVI),1)
diff --git a/ports/raspberrypi/supervisor/rp2_cpu.s b/ports/raspberrypi/supervisor/rp2_cpu.s
deleted file mode 100755
index 741bb21358ad2..0000000000000
--- a/ports/raspberrypi/supervisor/rp2_cpu.s
+++ /dev/null
@@ -1,35 +0,0 @@
-.syntax unified
-.cpu cortex-m0
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0, #0]
-str     r5, [r0, #4]
-str     r6, [r0, #8]
-str     r7, [r0, #12]
-push {r1}
-mov     r1, r8
-str     r1, [r0, #16]
-mov     r1, r9
-str     r1, [r0, #20]
-mov     r1, r10
-str     r1, [r0, #24]
-mov     r1, r11
-str     r1, [r0, #28]
-mov     r1, r12
-str     r1, [r0, #32]
-mov     r1, r13
-str     r1, [r0, #36]
-pop {r1}
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/renode/Makefile b/ports/renode/Makefile
index 170198455fbf5..22e32f9d2fb6e 100644
--- a/ports/renode/Makefile
+++ b/ports/renode/Makefile
@@ -45,7 +45,7 @@ SRC_C += \
 	background.c \
 	mphalport.c \
 
-SRC_S = supervisor/$(CPU)_cpu.s
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
 
 OBJ = $(PY_O) $(SUPERVISOR_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_COMMON_HAL_SHARED_MODULE_EXPANDED:.c=.o))
diff --git a/ports/renode/supervisor/cortex-m0+_cpu.s b/ports/renode/supervisor/cortex-m0+_cpu.s
deleted file mode 100755
index 741bb21358ad2..0000000000000
--- a/ports/renode/supervisor/cortex-m0+_cpu.s
+++ /dev/null
@@ -1,35 +0,0 @@
-.syntax unified
-.cpu cortex-m0
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0, #0]
-str     r5, [r0, #4]
-str     r6, [r0, #8]
-str     r7, [r0, #12]
-push {r1}
-mov     r1, r8
-str     r1, [r0, #16]
-mov     r1, r9
-str     r1, [r0, #20]
-mov     r1, r10
-str     r1, [r0, #24]
-mov     r1, r11
-str     r1, [r0, #28]
-mov     r1, r12
-str     r1, [r0, #32]
-mov     r1, r13
-str     r1, [r0, #36]
-pop {r1}
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/stm/Makefile b/ports/stm/Makefile
index 4bacecf60688a..baea6893a33d9 100755
--- a/ports/stm/Makefile
+++ b/ports/stm/Makefile
@@ -212,8 +212,8 @@ ifneq ($(CIRCUITPY_USB),0)
 	endif
 endif
 
+SRC_S_UPPER = supervisor/shared/cpu_regs.S
 SRC_S = \
-	supervisor/cpu.s \
 	st_driver/cmsis_device_$(MCU_SERIES_LOWER)/Source/Templates/gcc/startup_$(MCU_VARIANT_LOWER).s
 
 ifneq ($(FROZEN_MPY_DIR),)
@@ -229,6 +229,7 @@ OBJ += $(addprefix $(BUILD)/, $(SRC_LIBM:.c=.o))
 endif
 OBJ += $(addprefix $(BUILD)/, $(SRC_CIRCUITPY_COMMON:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_S:.s=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S_UPPER:.S=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_MOD:.c=.o))
 
 $(BUILD)/$(FATFS_DIR)/ff.o: COPT += -Os
diff --git a/ports/stm/supervisor/cpu.s b/ports/stm/supervisor/cpu.s
deleted file mode 100755
index 9e6807a5e2e99..0000000000000
--- a/ports/stm/supervisor/cpu.s
+++ /dev/null
@@ -1,27 +0,0 @@
-.syntax unified
-.cpu cortex-m4
-.thumb
-.text
-.align  2
-
-@ uint cpu_get_regs_and_sp(r0=uint regs[10])
-.global cpu_get_regs_and_sp
-.thumb
-.thumb_func
-.type   cpu_get_regs_and_sp, %function
-cpu_get_regs_and_sp:
-@ store registers into given array
-str     r4, [r0], #4
-str     r5, [r0], #4
-str     r6, [r0], #4
-str     r7, [r0], #4
-str     r8, [r0], #4
-str     r9, [r0], #4
-str     r10, [r0], #4
-str     r11, [r0], #4
-str     r12, [r0], #4
-str     r13, [r0], #4
-
-@ return the sp
-mov     r0, sp
-bx      lr
diff --git a/ports/zephyr-cp/cptools/build_circuitpython.py b/ports/zephyr-cp/cptools/build_circuitpython.py
index 905b281f7ea96..15ed46b794e22 100644
--- a/ports/zephyr-cp/cptools/build_circuitpython.py
+++ b/ports/zephyr-cp/cptools/build_circuitpython.py
@@ -575,7 +575,7 @@ async def build_circuitpython():
     source_files.append(portdir / "common-hal/zephyr_kernel/__init__.c")
     # source_files.append(srcdir / "ports" / port / "peripherals" / "nrf" / "nrf52840" / "pins.c")
 
-    assembly_files.append(srcdir / "ports/nordic/supervisor/cpu.s")
+    assembly_files.append(srcdir / "supervisor/shared/cpu_regs.S")
 
     source_files.extend(assembly_files)
 
diff --git a/supervisor/shared/cpu_regs.S b/supervisor/shared/cpu_regs.S
new file mode 100644
index 0000000000000..90e5367ed5808
--- /dev/null
+++ b/supervisor/shared/cpu_regs.S
@@ -0,0 +1,102 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2025 Scott Shawcroft for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+#include "supervisor/shared/cpu_regs.h"
+
+#ifdef __arm__
+.syntax unified
+.thumb
+.text
+.align  2
+
+@ uint cpu_get_regs_and_sp(r0=uint regs[SAVED_REGISTER_COUNT])
+.global cpu_get_regs_and_sp
+.thumb
+.thumb_func
+.type   cpu_get_regs_and_sp, %function
+cpu_get_regs_and_sp:
+#if __ARM_ARCH_ISA_THUMB == 2
+@ store registers into given array
+#ifdef __arm__
+stmia   r0!, {r4-r11}
+#endif
+#if defined(__aarch64__) && __aarch64__ == 1
+#error "aarch64 not supported"
+stmia   r0!, {x19-x28}
+#endif
+#ifdef __ARM_FP
+#ifdef __arm__
+vstmia   r0!, {s16-s31}
+#endif
+#if defined(__aarch64__) && __aarch64__ == 1
+vst1.64 {d8-d15}, [r0], #16
+#endif
+#endif
+#endif
+// Thumb 1 can only store directly from R0-R7. This is M0 and M23 mostly.
+#if __ARM_ARCH_ISA_THUMB == 1
+str     r4, [r0, #0]
+str     r5, [r0, #4]
+str     r6, [r0, #8]
+str     r7, [r0, #12]
+push {r1}
+mov     r1, r8
+str     r1, [r0, #16]
+mov     r1, r9
+str     r1, [r0, #20]
+mov     r1, r10
+str     r1, [r0, #24]
+mov     r1, r11
+str     r1, [r0, #28]
+mov     r1, r12
+str     r1, [r0, #32]
+mov     r1, r13
+str     r1, [r0, #36]
+pop {r1}
+#endif
+
+@ return the sp
+mov     r0, sp
+bx      lr
+#endif
+
+#ifdef __riscv
+#if __riscv_xlen == 32
+.global cpu_get_regs_and_sp
+.type   cpu_get_regs_and_sp, %function
+cpu_get_regs_and_sp:
+sw s0, 0(a0)
+sw s1, 4(a0)
+sw s2, 8(a0)
+sw s3, 12(a0)
+sw s4, 16(a0)
+sw s5, 20(a0)
+sw s6, 24(a0)
+sw s7, 28(a0)
+sw s8, 32(a0)
+sw s9, 36(a0)
+sw s10, 40(a0)
+sw s11, 44(a0)
+#ifdef __riscv_vector
+sw fs0, 48(a0)
+sw fs1, 52(a0)
+sw fs2, 56(a0)
+sw fs3, 60(a0)
+sw fs4, 64(a0)
+sw fs5, 68(a0)
+sw fs6, 72(a0)
+sw fs7, 76(a0)
+sw fs8, 80(a0)
+sw fs9, 84(a0)
+sw fs10, 88(a0)
+sw fs11, 92(a0)
+#endif
+move a0, sp
+ret
+#else
+#error "Unsupported RISC-V bit length"
+#endif
+#endif
diff --git a/supervisor/shared/cpu_regs.h b/supervisor/shared/cpu_regs.h
new file mode 100644
index 0000000000000..aff0b69ebab0c
--- /dev/null
+++ b/supervisor/shared/cpu_regs.h
@@ -0,0 +1,31 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2025 Scott Shawcroft for Adafruit Industries
+//
+// SPDX-License-Identifier: MIT
+
+#pragma once
+
+#ifdef __arm__
+#define INTEGER_REGS 8
+#ifdef __ARM_FP
+#define FLOATING_POINT_REGS 16
+#endif
+#endif
+
+#ifdef __aarch64__
+#define INTEGER_REGS 10
+#ifdef __ARM_FP
+#define FLOATING_POINT_REGS 8
+#endif
+#endif
+
+#ifndef INTEGER_REGS
+#define INTEGER_REGS 0
+#endif
+
+#ifndef FLOATING_POINT_REGS
+#define FLOATING_POINT_REGS 0
+#endif
+
+#define SAVED_REGISTER_COUNT (INTEGER_REGS + FLOATING_POINT_REGS)