diff --git a/ports/stm32/Makefile b/ports/stm32/Makefile
index 8d920ae953..3bb18ee3cb 100644
--- a/ports/stm32/Makefile
+++ b/ports/stm32/Makefile
@@ -25,12 +25,11 @@ include ../../py/mkenv.mk
 -include mpconfigport.mk
 include $(BOARD_DIR)/mpconfigboard.mk
 
-# Files that are generated and needed before the QSTR build.
-QSTR_GENERATED_HEADERS = $(GEN_PINS_QSTR) $(GEN_STMCONST_QSTR)
-
 # qstr definitions (must come before including py.mk)
-QSTR_DEFS += qstrdefsport.h $(QSTR_GENERATED_HEADERS)
-QSTR_GLOBAL_DEPENDENCIES += mpconfigboard_common.h $(BOARD_DIR)/mpconfigboard.h $(QSTR_GENERATED_HEADERS)
+QSTR_DEFS += qstrdefsport.h
+
+# Files that are generated and needed before the QSTR build.
+QSTR_GLOBAL_DEPENDENCIES += mpconfigboard_common.h $(BOARD_DIR)/mpconfigboard.h $(GEN_STMCONST_HDR)
 
 # MicroPython feature configurations
 MICROPY_ROM_TEXT_COMPRESSION ?= 1
@@ -71,7 +70,6 @@ BOARD_PINS = $(BOARD_DIR)/pins.csv
 PREFIX_FILE = boards/stm32f4xx_prefix.c
 GEN_PINS_SRC = $(BUILD)/pins_$(BOARD).c
 GEN_PINS_HDR = $(HEADER_BUILD)/pins.h
-GEN_PINS_QSTR = $(BUILD)/pins_qstr.h
 GEN_PINS_AF_CONST = $(HEADER_BUILD)/pins_af_const.h
 GEN_PINS_AF_DEFS = $(HEADER_BUILD)/pins_af_defs.h
 GEN_PINS_AF_PY = $(BUILD)/pins_af.py
@@ -86,7 +84,6 @@ GEN_CDCINF_HEADER = $(HEADER_BUILD)/pybcdc_inf.h
 
 GEN_PLLFREQTABLE_HDR = $(HEADER_BUILD)/pllfreqtable.h
 GEN_STMCONST_HDR = $(HEADER_BUILD)/modstm_const.h
-GEN_STMCONST_QSTR = $(BUILD)/modstm_qstr.h
 GEN_STMCONST_MPZ = $(HEADER_BUILD)/modstm_mpz.h
 CMSIS_MCU_HDR = $(STM32LIB_CMSIS_ABS)/Include/$(CMSIS_MCU_LOWER).h
 
@@ -655,7 +652,7 @@ $(BUILD)/firmware.elf: $(OBJ)
 	$(call GENERATE_ELF,$@,$^)
 
 # List of sources for qstr extraction
-SRC_QSTR += $(SRC_C) $(SRC_CXX) $(SHARED_SRC_C)
+SRC_QSTR += $(SRC_C) $(SRC_CXX) $(SHARED_SRC_C) $(GEN_PINS_SRC)
 # Append any auto-generated sources that are needed by sources listed in
 # SRC_QSTR
 SRC_QSTR_AUTO_DEPS += $(GEN_CDCINF_HEADER)
@@ -676,13 +673,12 @@ main.c: $(GEN_CDCINF_HEADER)
 
 # Use a pattern rule here so that make will only call make-pins.py once to make
 # both pins_$(BOARD).c and pins.h
-$(BUILD)/%_$(BOARD).c $(HEADER_BUILD)/%.h $(HEADER_BUILD)/%_af_const.h $(HEADER_BUILD)/%_af_defs.h $(BUILD)/%_qstr.h: $(BOARD_DIR)/%.csv $(MAKE_PINS) $(AF_FILE) $(PREFIX_FILE) | $(HEADER_BUILD)
+$(BUILD)/%_$(BOARD).c $(HEADER_BUILD)/%.h $(HEADER_BUILD)/%_af_const.h $(HEADER_BUILD)/%_af_defs.h: $(BOARD_DIR)/%.csv $(MAKE_PINS) $(AF_FILE) $(PREFIX_FILE) | $(HEADER_BUILD)
 	$(ECHO) "GEN $@"
 	$(Q)$(PYTHON) $(MAKE_PINS) --board $(BOARD_PINS) --af $(AF_FILE) \
 		--prefix $(PREFIX_FILE) --hdr $(GEN_PINS_HDR) --hdr-obj-decls \
-		--qstr $(GEN_PINS_QSTR) --af-const $(GEN_PINS_AF_CONST) \
-		--af-defs $(GEN_PINS_AF_DEFS) --af-defs-cmp-strings \
-		--af-py $(GEN_PINS_AF_PY) > $(GEN_PINS_SRC)
+		--af-const $(GEN_PINS_AF_CONST) --af-defs $(GEN_PINS_AF_DEFS) \
+		--af-defs-cmp-strings --af-py $(GEN_PINS_AF_PY) > $(GEN_PINS_SRC)
 
 modmachine.c: $(GEN_PLLFREQTABLE_HDR)
 $(GEN_PLLFREQTABLE_HDR): $(PLLVALUES) | $(HEADER_BUILD)
@@ -690,11 +686,9 @@ $(GEN_PLLFREQTABLE_HDR): $(PLLVALUES) | $(HEADER_BUILD)
 	$(Q)$(PYTHON) $(PLLVALUES) -c -m $(CMSIS_MCU_LOWER) file:$(BOARD_DIR)/stm32$(MCU_SERIES)xx_hal_conf.h > $@
 
 $(BUILD)/modstm.o: $(GEN_STMCONST_HDR)
-# Use a pattern rule here so that make will only call make-stmconst.py once to
-# make both modstm_const.h and modstm_qstr.h
-$(HEADER_BUILD)/%_const.h $(BUILD)/%_qstr.h: $(CMSIS_MCU_HDR) make-stmconst.py | $(HEADER_BUILD)
+$(HEADER_BUILD)/modstm_const.h: $(CMSIS_MCU_HDR) make-stmconst.py | $(HEADER_BUILD)
 	$(ECHO) "GEN stmconst $@"
-	$(Q)$(PYTHON) make-stmconst.py --qstr $(GEN_STMCONST_QSTR) --mpz $(GEN_STMCONST_MPZ) $(CMSIS_MCU_HDR) > $(GEN_STMCONST_HDR)
+	$(Q)$(PYTHON) make-stmconst.py --mpz $(GEN_STMCONST_MPZ) $(CMSIS_MCU_HDR) > $(GEN_STMCONST_HDR)
 
 $(GEN_CDCINF_HEADER): $(GEN_CDCINF_FILE) $(FILE2H) | $(HEADER_BUILD)
 	$(ECHO) "GEN $@"
diff --git a/ports/stm32/boards/make-pins.py b/ports/stm32/boards/make-pins.py
index a3e6ee0669..f0fcb82437 100755
--- a/ports/stm32/boards/make-pins.py
+++ b/ports/stm32/boards/make-pins.py
@@ -188,9 +188,6 @@ class AlternateFunction(object):
         )
         print_conditional_endif(cond_var)
 
-    def qstr_list(self):
-        return [self.mux_name()]
-
 
 class Pin(object):
     """Holds the information associated with a pin."""
@@ -301,13 +298,6 @@ class Pin(object):
         if self.alt_fn_count > 0:
             hdr_file.write("extern const pin_af_obj_t pin_{:s}_af[];\n".format(n))
 
-    def qstr_list(self):
-        result = []
-        for alt_fn in self.alt_fn:
-            if alt_fn.is_supported():
-                result += alt_fn.qstr_list()
-        return result
-
 
 class NamedPin(object):
     def __init__(self, name, pin):
@@ -462,26 +452,6 @@ class Pins(object):
                     )
                 )
 
-    def print_qstr(self, qstr_filename):
-        with open(qstr_filename, "wt") as qstr_file:
-            qstr_set = set([])
-            for named_pin in self.cpu_pins:
-                pin = named_pin.pin()
-                if pin.is_board_pin():
-                    qstr_set |= set(pin.qstr_list())
-                    qstr_set |= set([named_pin.name()])
-            for named_pin in self.board_pins:
-                if not named_pin.is_hidden():
-                    qstr_set |= set([named_pin.name()])
-            for qstr in sorted(qstr_set):
-                cond_var = None
-                if qstr.startswith("AF"):
-                    af_words = qstr.split("_")
-                    cond_var = conditional_var(af_words[1])
-                    print_conditional_if(cond_var, file=qstr_file)
-                print("Q({})".format(qstr), file=qstr_file)
-                print_conditional_endif(cond_var, file=qstr_file)
-
     def print_af_hdr(self, af_const_filename):
         with open(af_const_filename, "wt") as af_const_file:
             af_hdr_set = set([])
@@ -597,13 +567,6 @@ def main():
         help="Specifies beginning portion of generated pins file",
         default="stm32f4xx_prefix.c",
     )
-    parser.add_argument(
-        "-q",
-        "--qstr",
-        dest="qstr_filename",
-        help="Specifies name of generated qstr header file",
-        default="build/pins_qstr.h",
-    )
     parser.add_argument(
         "-r",
         "--hdr",
@@ -640,7 +603,6 @@ def main():
     for i in range(1, 4):
         pins.print_adc(i)
     pins.print_header(args.hdr_filename, args.hdr_obj_decls)
-    pins.print_qstr(args.qstr_filename)
     pins.print_af_hdr(args.af_const_filename)
     pins.print_af_py(args.af_py_filename)
     pins.print_af_defs(args.af_defs_filename, args.af_defs_cmp_strings)
diff --git a/ports/stm32/make-stmconst.py b/ports/stm32/make-stmconst.py
index 4e4f2d7155..6d64fe3cfa 100644
--- a/ports/stm32/make-stmconst.py
+++ b/ports/stm32/make-stmconst.py
@@ -183,22 +183,20 @@ def print_int_obj(val, needed_mpzs):
         needed_mpzs.add(val)
 
 
-def print_periph(periph_name, periph_val, needed_qstrs, needed_mpzs):
+def print_periph(periph_name, periph_val, needed_mpzs):
     qstr = periph_name.upper()
     print("{ MP_ROM_QSTR(MP_QSTR_%s), " % qstr, end="")
     print_int_obj(periph_val, needed_mpzs)
     print(" },")
-    needed_qstrs.add(qstr)
 
 
-def print_regs(reg_name, reg_defs, needed_qstrs, needed_mpzs):
+def print_regs(reg_name, reg_defs, needed_mpzs):
     reg_name = reg_name.upper()
     for r in reg_defs:
         qstr = reg_name + "_" + r[0]
         print("{ MP_ROM_QSTR(MP_QSTR_%s), " % qstr, end="")
         print_int_obj(r[1], needed_mpzs)
         print(" }, // %s-bits, %s" % (r[2], r[3]))
-        needed_qstrs.add(qstr)
 
 
 # This version of print regs groups registers together into submodules (eg GPIO submodule).
@@ -208,7 +206,7 @@ def print_regs(reg_name, reg_defs, needed_qstrs, needed_mpzs):
 # As such, we don't use this version.
 # And for the number of constants we have, this function seems to use about the same amount
 # of ROM as print_regs.
-def print_regs_as_submodules(reg_name, reg_defs, modules, needed_qstrs):
+def print_regs_as_submodules(reg_name, reg_defs, modules):
     mod_name_lower = reg_name.lower() + "_"
     mod_name_upper = mod_name_lower.upper()
     modules.append((mod_name_lower, mod_name_upper))
@@ -220,14 +218,12 @@ STATIC const mp_rom_map_elem_t stm_%s_globals_table[] = {
 """
         % (mod_name_lower, mod_name_upper)
     )
-    needed_qstrs.add(mod_name_upper)
 
     for r in reg_defs:
         print(
             "    { MP_ROM_QSTR(MP_QSTR_%s), MP_ROM_INT(%#x) }, // %s-bits, %s"
             % (r[0], r[1], r[2], r[3])
         )
-        needed_qstrs.add(r[0])
 
     print(
         """};
@@ -247,13 +243,6 @@ const mp_obj_module_t stm_%s_obj = {
 def main():
     cmd_parser = argparse.ArgumentParser(description="Extract ST constants from a C header file.")
     cmd_parser.add_argument("file", nargs=1, help="input file")
-    cmd_parser.add_argument(
-        "-q",
-        "--qstr",
-        dest="qstr_filename",
-        default="build/stmconst_qstr.h",
-        help="Specified the name of the generated qstr header file",
-    )
     cmd_parser.add_argument(
         "--mpz",
         dest="mpz_filename",
@@ -269,14 +258,13 @@ def main():
         reg_defs["GPIO"].append(["BSRRL", 0x18, 16, "legacy register"])
         reg_defs["GPIO"].append(["BSRRH", 0x1A, 16, "legacy register"])
 
-    needed_qstrs = set()
     needed_mpzs = set()
 
     print("// Automatically generated from %s by make-stmconst.py" % args.file[0])
     print("")
 
     for periph_name, periph_val in periphs:
-        print_periph(periph_name, periph_val, needed_qstrs, needed_mpzs)
+        print_periph(periph_name, periph_val, needed_mpzs)
 
     for reg in (
         "ADC",
@@ -309,8 +297,8 @@ def main():
         "IPCC",
     ):
         if reg in reg_defs:
-            print_regs(reg, reg_defs[reg], needed_qstrs, needed_mpzs)
-        # print_regs_as_submodules(reg, reg_defs[reg], modules, needed_qstrs)
+            print_regs(reg, reg_defs[reg], needed_mpzs)
+        # print_regs_as_submodules(reg, reg_defs[reg], modules)
 
     # print("#define MOD_STM_CONST_MODULES \\")
     # for mod_lower, mod_upper in modules:
@@ -318,12 +306,6 @@ def main():
 
     print("")
 
-    with open(args.qstr_filename, "wt") as qstr_file:
-        print("#if MICROPY_PY_STM_CONST", file=qstr_file)
-        for qstr in sorted(needed_qstrs):
-            print("Q({})".format(qstr), file=qstr_file)
-        print("#endif // MICROPY_PY_STM_CONST", file=qstr_file)
-
     with open(args.mpz_filename, "wt") as mpz_file:
         for mpz in sorted(needed_mpzs):
             assert 0 <= mpz <= 0xFFFFFFFF
diff --git a/ports/stm32/mboot/Makefile b/ports/stm32/mboot/Makefile
index 54fc8f4830..a37b046ca5 100755
--- a/ports/stm32/mboot/Makefile
+++ b/ports/stm32/mboot/Makefile
@@ -227,7 +227,6 @@ GEN_QSTRDEFS_GENERATED = $(HEADER_BUILD)/qstrdefs.generated.h
 GEN_ROOT_POINTERS = $(HEADER_BUILD)/root_pointers.h
 GEN_PINS_SRC = $(BUILD)/pins_$(BOARD).c
 GEN_PINS_HDR = $(HEADER_BUILD)/pins.h
-GEN_PINS_QSTR = $(HEADER_BUILD)/pins_qstr.h
 GEN_PINS_AF_CONST = $(HEADER_BUILD)/pins_af_const.h
 GEN_PINS_AF_DEFS = $(HEADER_BUILD)/pins_af_defs.h
 GEN_PINS_AF_PY = $(BUILD)/pins_af.py
@@ -246,7 +245,7 @@ $(GEN_ROOT_POINTERS): | $(HEADER_BUILD)
 $(GEN_PINS_AF_DEFS): $(BOARD_PINS) $(MAKE_PINS) ../$(AF_FILE) $(PREFIX_FILE) | $(HEADER_BUILD)
 	$(ECHO) "GEN $@"
 	$(Q)$(PYTHON) $(MAKE_PINS) --board $(BOARD_PINS) --af ../$(AF_FILE) \
-		--prefix $(PREFIX_FILE) --hdr $(GEN_PINS_HDR) --qstr $(GEN_PINS_QSTR) \
+		--prefix $(PREFIX_FILE) --hdr $(GEN_PINS_HDR) \
 		--af-const $(GEN_PINS_AF_CONST) --af-defs $(GEN_PINS_AF_DEFS) \
 		--af-py $(GEN_PINS_AF_PY) > $(GEN_PINS_SRC)