diff --git a/hw/mcu/st/cmsis_device_f4 b/hw/mcu/st/cmsis_device_f4
new file mode 160000
index 000000000..3c77349ce
--- /dev/null
+++ b/hw/mcu/st/cmsis_device_f4
@@ -0,0 +1 @@
+Subproject commit 3c77349ce04c8af401454cc51f85ea9a50e34fc1
diff --git a/hw/mcu/st/stm32f4xx_hal_driver b/hw/mcu/st/stm32f4xx_hal_driver
new file mode 160000
index 000000000..b6f0ed382
--- /dev/null
+++ b/hw/mcu/st/stm32f4xx_hal_driver
@@ -0,0 +1 @@
+Subproject commit b6f0ed3829f3829eb358a2e7417d80bba1a42db7
diff --git a/lib/CMSIS_5 b/lib/CMSIS_5
new file mode 160000
index 000000000..2b7495b85
--- /dev/null
+++ b/lib/CMSIS_5
@@ -0,0 +1 @@
+Subproject commit 2b7495b8535bdcb306dac29b9ded4cfb679d7e5c
diff --git a/lib/FreeRTOS-Kernel b/lib/FreeRTOS-Kernel
new file mode 160000
index 000000000..cc0e0707c
--- /dev/null
+++ b/lib/FreeRTOS-Kernel
@@ -0,0 +1 @@
+Subproject commit cc0e0707c0c748713485b870bb980852b210877f
diff --git a/lib/lwip b/lib/lwip
new file mode 160000
index 000000000..159e31b68
--- /dev/null
+++ b/lib/lwip
@@ -0,0 +1 @@
+Subproject commit 159e31b689577dbf69cf0683bbaffbd71fa5ee10
diff --git a/lib/threadx b/lib/threadx
new file mode 160000
index 000000000..4b6e8100d
--- /dev/null
+++ b/lib/threadx
@@ -0,0 +1 @@
+Subproject commit 4b6e8100d932a3a67b34c6eb17f84f3bffb9e2ae
diff --git a/src/class/net/ecm_rndis_device.c b/src/class/net/ecm_rndis_device.c
index eaa82c187..773c495ed 100644
--- a/src/class/net/ecm_rndis_device.c
+++ b/src/class/net/ecm_rndis_device.c
@@ -356,8 +356,8 @@ bool netd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_
   /* data transmission finished */
   if (ep_addr == _netd_itf.ep_in) {
     /* TinyUSB requires the class driver to implement ZLP (since ZLP usage is class-specific) */
-
-    if (xferred_bytes && (0 == (xferred_bytes % CFG_TUD_NET_ENDPOINT_SIZE))) {
+    uint16_t const ep_size = (tud_speed_get() == TUSB_SPEED_HIGH) ? 512 : 64;
+    if (xferred_bytes && (0 == (xferred_bytes % ep_size))) {
       do_in_xfer(NULL, 0); /* a ZLP is needed */
     } else {
       /* we're finally finished */
diff --git a/src/class/net/ncm_device.c b/src/class/net/ncm_device.c
index 405e4467b..4f75dc478 100644
--- a/src/class/net/ncm_device.c
+++ b/src/class/net/ncm_device.c
@@ -340,7 +340,7 @@ static xmit_ntb_t *xmit_get_next_ready_ntb(void) {
 static bool xmit_insert_required_zlp(uint8_t rhport, uint32_t xferred_bytes) {
   TU_LOG_DRV("xmit_insert_required_zlp(%d,%ld)\n", rhport, xferred_bytes);
 
-  if (xferred_bytes == 0 || xferred_bytes % CFG_TUD_NET_ENDPOINT_SIZE != 0) {
+  if (xferred_bytes == 0 || xferred_bytes % (tud_speed_get() == TUSB_SPEED_HIGH ? 512 : 64) != 0) {
     return false;
   }
 
diff --git a/src/class/net/net_device.h b/src/class/net/net_device.h
index 96c03fd61..849f8a2f9 100644
--- a/src/class/net/net_device.h
+++ b/src/class/net/net_device.h
@@ -35,9 +35,6 @@
 #error "Cannot enable both ECM_RNDIS and NCM network drivers"
 #endif
 
-/* declared here, NOT in usb_descriptors.c, so that the driver can intelligently ZLP as needed */
-#define CFG_TUD_NET_ENDPOINT_SIZE (TUD_OPT_HIGH_SPEED ? 512 : 64)
-
 /* Maximum Transmission Unit (in bytes) of the network, including Ethernet header */
 #ifndef CFG_TUD_NET_MTU
 #define CFG_TUD_NET_MTU           1514
diff --git a/tools/linkermap b/tools/linkermap
new file mode 160000
index 000000000..8e1f440fa
--- /dev/null
+++ b/tools/linkermap
@@ -0,0 +1 @@
+Subproject commit 8e1f440fa15c567aceb5aa0d14f6d18c329cc67f
diff --git a/tools/uf2 b/tools/uf2
new file mode 160000
index 000000000..c594542b2
--- /dev/null
+++ b/tools/uf2
@@ -0,0 +1 @@
+Subproject commit c594542b2faa01cc33a2b97c9fbebc38549df80a