rename ep_fifo_size (bytes) to otg_dfifo_depth (words)

12 files changed, 95 insertions, 78 deletions

diff --git a/src/portable/synopsys/dwc2/dcd_dwc2.c b/src/portable/synopsys/dwc2/dcd_dwc2.c
index e32dedd1b..bdd3a59ed 100644
--- a/src/portable/synopsys/dwc2/dcd_dwc2.c
+++ b/src/portable/synopsys/dwc2/dcd_dwc2.c
@@ -148,22 +148,23 @@ static void dma_setup_prepare(uint8_t rhport) {
 
 
 /* Device Data FIFO scheme
+  The controller has a single SPRAM of otg_dfifo_depth 32-bit words shared between all FIFOs and optional DMA metadata.
+  otg_dfifo_depth = ghwcfg3.dfifo_depth + EP_LOC_CNT. It is split up into:
 
-  The FIFO is split up into
-  - EPInfo: for storing DMA metadata, only required when use DMA. Maximum size is called
-    EP_LOC_CNT = ep_fifo_size - ghwcfg3.dfifo_depth. For value less than EP_LOC_CNT, gdfifocfg must be configured before
-    gahbcfg.dmaen is set
-      - Buffer mode: 1 word per endpoint direction
-      - Scatter/Gather DMA: 4 words per endpoint direction
+  - EPInfo: for storing DMA address registers (DxEPDMAn), only required when DMA is used.
+    gdfifocfg.EPINFOBASE and gdfifocfg.GDFIFOCfg must be configured before gahbcfg.dmaen is set.
+    The number of words needed per endpoint direction depends on the DMA mode used at runtime:
+      - Buffer DMA mode: 1 word per endpoint direction
+      - Scatter/Gather DMA mode: 4 words per endpoint direction
   - TX FIFO: one fifo for each IN endpoint. Size is dynamic depending on packet size, starting from top with EP0 IN.
   - Shared RX FIFO: a shared fifo for all OUT endpoints. Typically, can hold up to 2 packets of the largest EP size.
 
-  We allocated TX FIFO from top to bottom (using top pointer), this to allow the RX FIFO to grow dynamically which is
+  We allocate TX FIFOs from top to bottom (using a top pointer), this to allow the RX FIFO to grow dynamically, which is
   possible since the free space is located between the RX and TX FIFOs.
 
-   ---------------- ep_fifo_size
-  |  DxEPIDMAn  |
-  |-------------|-- gdfifocfg.EPINFOBASE (max is ghwcfg3.dfifo_depth)
+   --------------- otg_dfifo_depth
+  |  EPInfo      |   DxEPDMAn (DMA only, sized per runtime DMA mode)
+  |-------------|-- gdfifocfg.EPINFOBASE (= gdfifocfg.GDFIFOCfg)
   | IN FIFO 0   |       control EP
   |-------------|
   | IN FIFO 1   |
@@ -184,9 +185,9 @@ static void dma_setup_prepare(uint8_t rhport) {
     - 13 for setup packets + control words (up to 3 setup packets).
     - 1 for global NAK (not required/used here).
     - Largest-EPsize/4 + 1. (FS: 64 bytes, HS: 512 bytes). Recommended is  "2 x (Largest-EPsize/4 + 1)"
-    - 2 for each used OUT endpoint
+    - 2 for each used OUT endpoint.
 
-    Therefore GRXFSIZ = 13 + 1 + 2 x (Largest-EPsize/4 + 1) + 2 x EPOUTnum
+    Therefore, GRXFSIZ = 13 + 1 + 2 x (Largest-EPsize/4 + 1) + 2 x EPOUTnum
 */
 
 TU_ATTR_ALWAYS_INLINE static inline uint16_t calc_device_grxfsiz(uint16_t largest_ep_size, uint8_t ep_count) {
@@ -249,7 +250,7 @@ static void dfifo_device_init(uint8_t rhport) {
 
   // Scatter/Gather DMA mode is not yet supported. Buffer DMA only need 1 words per endpoint direction
   const bool is_dma = dma_device_enabled(dwc2);
-  _dcd_data.dfifo_top = dwc2_controller->ep_fifo_size/4;
+  _dcd_data.dfifo_top = dwc2_controller->otg_dfifo_depth;
   if (is_dma) {
     _dcd_data.dfifo_top -= 2 * dwc2_controller->ep_count;
   }
diff --git a/src/portable/synopsys/dwc2/dwc2_at32.h b/src/portable/synopsys/dwc2/dwc2_at32.h
index fa6d10c12..594d350b7 100644
--- a/src/portable/synopsys/dwc2/dwc2_at32.h
+++ b/src/portable/synopsys/dwc2/dwc2_at32.h
@@ -32,38 +32,38 @@
 
 #if CFG_TUSB_MCU == OPT_MCU_AT32F415
   #include <at32f415.h>
-  #define OTG1_FIFO_SIZE           1280
+  #define OTG1_DFIFO_DEPTH           320
   #define OTG1_IRQn                OTGFS1_IRQn
   #define DWC2_OTG1_REG_BASE       0x50000000UL
 #elif CFG_TUSB_MCU == OPT_MCU_AT32F435_437
   #include <at32f435_437.h>
-  #define OTG1_FIFO_SIZE           1280
-  #define OTG2_FIFO_SIZE           1280
+  #define OTG1_DFIFO_DEPTH           320
+  #define OTG2_DFIFO_DEPTH           320
   #define OTG1_IRQn                OTGFS1_IRQn
   #define OTG2_IRQn                OTGFS2_IRQn
   #define DWC2_OTG1_REG_BASE       0x50000000UL
   #define DWC2_OTG2_REG_BASE       0x40040000UL
 #elif CFG_TUSB_MCU == OPT_MCU_AT32F423
   #include <at32f423.h>
-  #define OTG1_FIFO_SIZE           1280
+  #define OTG1_DFIFO_DEPTH           320
   #define OTG1_IRQn                OTGFS1_IRQn
   #define DWC2_OTG1_REG_BASE       0x50000000UL
 #elif CFG_TUSB_MCU == OPT_MCU_AT32F402_405
   #include <at32f402_405.h>
-  #define OTG1_FIFO_SIZE           1280
-  #define OTG2_FIFO_SIZE           4096
+  #define OTG1_DFIFO_DEPTH           320
+  #define OTG2_DFIFO_DEPTH           1024
   #define OTG1_IRQn                OTGFS1_IRQn
   #define OTG2_IRQn                OTGHS_IRQn
   #define DWC2_OTG1_REG_BASE       0x50000000UL
   #define DWC2_OTG2_REG_BASE       0x40040000UL //OTGHS
 #elif CFG_TUSB_MCU == OPT_MCU_AT32F425
   #include <at32f425.h>
-  #define OTG1_FIFO_SIZE           1280
+  #define OTG1_DFIFO_DEPTH           320
   #define OTG1_IRQn                OTGFS1_IRQn
   #define DWC2_OTG1_REG_BASE       0x50000000UL
 #elif CFG_TUSB_MCU == OPT_MCU_AT32F45X
   #include <at32f45x.h>
-  #define OTG1_FIFO_SIZE           1280
+  #define OTG1_DFIFO_DEPTH           320
   #define OTG1_IRQn                OTGFS1_IRQn
   #define DWC2_OTG1_REG_BASE       0x50000000UL
 #endif
@@ -73,9 +73,9 @@ extern "C" {
 #endif
 
 static const dwc2_controller_t _dwc2_controller[] = {
-    {.reg_base = DWC2_OTG1_REG_BASE, .irqnum = OTG1_IRQn, .ep_count = DWC2_EP_MAX, .ep_fifo_size = OTG1_FIFO_SIZE},
+    {.reg_base = DWC2_OTG1_REG_BASE, .irqnum = OTG1_IRQn, .ep_count = DWC2_EP_MAX, .otg_dfifo_depth = OTG1_DFIFO_DEPTH},
 #if defined DWC2_OTG2_REG_BASE
-    {.reg_base = DWC2_OTG2_REG_BASE, .irqnum = OTG2_IRQn, .ep_count = DWC2_EP_MAX, .ep_fifo_size = OTG2_FIFO_SIZE}
+    {.reg_base = DWC2_OTG2_REG_BASE, .irqnum = OTG2_IRQn, .ep_count = DWC2_EP_MAX, .otg_dfifo_depth = OTG2_DFIFO_DEPTH}
 #endif
 };
 
diff --git a/src/portable/synopsys/dwc2/dwc2_bcm.h b/src/portable/synopsys/dwc2/dwc2_bcm.h
index 00842bba2..50f3122e8 100644
--- a/src/portable/synopsys/dwc2/dwc2_bcm.h
+++ b/src/portable/synopsys/dwc2/dwc2_bcm.h
@@ -39,7 +39,7 @@
 
 static const dwc2_controller_t _dwc2_controller[] =
 {
-  { .reg_base = USB_OTG_GLOBAL_BASE, .irqnum = USB_IRQn, .ep_count = DWC2_EP_MAX, .ep_fifo_size = 16384 }
+  { .reg_base = USB_OTG_GLOBAL_BASE, .irqnum = USB_IRQn, .ep_count = DWC2_EP_MAX, .otg_dfifo_depth = 4096 }
 };
 
 #define dcache_clean(_addr, _size)              data_clean(_addr, _size)
diff --git a/src/portable/synopsys/dwc2/dwc2_efm32.h b/src/portable/synopsys/dwc2/dwc2_efm32.h
index e1cb7c769..167f5b4cd 100644
--- a/src/portable/synopsys/dwc2/dwc2_efm32.h
+++ b/src/portable/synopsys/dwc2/dwc2_efm32.h
@@ -40,7 +40,7 @@
 
 static const dwc2_controller_t _dwc2_controller[] =
 {
-  { .reg_base = DWC2_REG_BASE, .irqnum = USB_IRQn, .ep_count = DWC2_EP_MAX, .ep_fifo_size = 2048 }
+  { .reg_base = DWC2_REG_BASE, .irqnum = USB_IRQn, .ep_count = DWC2_EP_MAX, .otg_dfifo_depth = 512 }
 };
 
 TU_ATTR_ALWAYS_INLINE
diff --git a/src/portable/synopsys/dwc2/dwc2_esp32.h b/src/portable/synopsys/dwc2/dwc2_esp32.h
index ff9f216bd..99ef9456f 100644
--- a/src/portable/synopsys/dwc2/dwc2_esp32.h
+++ b/src/portable/synopsys/dwc2/dwc2_esp32.h
@@ -44,7 +44,7 @@
 #define DWC2_EP_MAX        7
 
 static const dwc2_controller_t _dwc2_controller[] = {
-  { .reg_base = DWC2_FS_REG_BASE, .irqnum = ETS_USB_INTR_SOURCE, .ep_count = 7, .ep_in_count = 5, .ep_fifo_size = 1024 }
+  { .reg_base = DWC2_FS_REG_BASE, .irqnum = ETS_USB_INTR_SOURCE, .ep_count = 7, .ep_in_count = 5, .otg_dfifo_depth = 256 }
 };
 
 #elif TU_CHECK_MCU(OPT_MCU_ESP32H4)
@@ -61,7 +61,7 @@ static const dwc2_controller_t _dwc2_controller[] = {
 #define DWC2_EP_MAX        7
 
 static const dwc2_controller_t _dwc2_controller[] = {
-  { .reg_base = DWC2_FS_REG_BASE, .irqnum = ETS_USB_OTG11_INTR_SOURCE, .ep_count = 7, .ep_in_count = 5, .ep_fifo_size = 1024 }
+  { .reg_base = DWC2_FS_REG_BASE, .irqnum = ETS_USB_OTG11_INTR_SOURCE, .ep_count = 7, .ep_in_count = 5, .otg_dfifo_depth = 256 }
 };
 
 #elif TU_CHECK_MCU(OPT_MCU_ESP32P4)
@@ -72,8 +72,8 @@ static const dwc2_controller_t _dwc2_controller[] = {
 // On ESP32 for consistency we associate
 // - Port0 to OTG_FS, and Port1 to OTG_HS
 static const dwc2_controller_t _dwc2_controller[] = {
-  { .reg_base = DWC2_FS_REG_BASE, .irqnum = ETS_USB_OTG11_CH0_INTR_SOURCE, .ep_count = 7, .ep_in_count = 5, .ep_fifo_size = 1024 },
-  { .reg_base = DWC2_HS_REG_BASE, .irqnum = ETS_USB_OTG_INTR_SOURCE, .ep_count = 16, .ep_in_count = 8, .ep_fifo_size = 4096 }
+  { .reg_base = DWC2_FS_REG_BASE, .irqnum = ETS_USB_OTG11_CH0_INTR_SOURCE, .ep_count = 7, .ep_in_count = 5, .otg_dfifo_depth = 256 },
+  { .reg_base = DWC2_HS_REG_BASE, .irqnum = ETS_USB_OTG_INTR_SOURCE, .ep_count = 16, .ep_in_count = 8, .otg_dfifo_depth = 1024 }
 };
 #endif
 
diff --git a/src/portable/synopsys/dwc2/dwc2_gd32.h b/src/portable/synopsys/dwc2/dwc2_gd32.h
index ccbf93a76..396d17e30 100644
--- a/src/portable/synopsys/dwc2/dwc2_gd32.h
+++ b/src/portable/synopsys/dwc2/dwc2_gd32.h
@@ -37,7 +37,7 @@
 
 static const dwc2_controller_t _dwc2_controller[] =
 {
-  { .reg_base = DWC2_REG_BASE, .irqnum = 86, .ep_count = DWC2_EP_MAX, .ep_fifo_size = 1280 }
+  { .reg_base = DWC2_REG_BASE, .irqnum = 86, .ep_count = DWC2_EP_MAX, .otg_dfifo_depth = 320 }
 };
 
 extern uint32_t SystemCoreClock;
diff --git a/src/portable/synopsys/dwc2/dwc2_info.py b/src/portable/synopsys/dwc2/dwc2_info.py
index bdf63d590..eab95ffe1 100755
--- a/src/portable/synopsys/dwc2/dwc2_info.py
+++ b/src/portable/synopsys/dwc2/dwc2_info.py
@@ -9,14 +9,14 @@ import pandas as pd
 dwc2_reg_list = ['GUID', 'GSNPSID', 'GHWCFG1', 'GHWCFG2', 'GHWCFG3', 'GHWCFG4']
 dwc2_reg_value = {
     'AT32 F405 FS': [0x00002000, 0x4F54400A, 0x00000000, 0x228FDD00, 0x020004E8, 0x1FF0A020],
-    'AT32 F405 HS': [0x00000000, 0x4F54400A, 0x00000000, 0x229FDDD0, 0x03F006E8, 0x1FF0A020],
+    'AT32 F405 HS': [0, 0x4F54400A, 0x00000000, 0x229FDDD0, 0x03F006E8, 0x1FF0A020],
     'AT32 F415': [0x00001000, 0x4F54400A, 0x00000000, 0x228DCD00, 0x020004E8, 0x0F],
     'BCM2711 (Pi4)': [0x2708A000, 0x4F54280A, 0, 0x228DDD50, 0xFF000E8, 0x1FF00020],
     'EFM32GG': [0, 0x4F54330A, 0, 0x228F5910, 0x01F204E8, 0x1BF08030],
     'ESP32-S2/S3': [0, 0x4F54400A, 0, 0x224DD930, 0x0C804B5, 0xD3F0A030],
     'ESP32-P4': [0, 0x4F54400A, 0, 0x215FFFD0, 0x03805EB5, 0xDFF1A030],
-    'nRF54': [0, 0x4F54430A, 0xAA555000, 0x228BFC72, 0x0BEAC0E8, 0x1E10AA60],
-    'nRF54LM20': [0x00000000, 0x4F54500B, 0x00000000, 0x22AFFC52, 0x0BE0C0E8, 0x3E10AA60],
+    # 'nRF54H20': [0, 0x4F54430A, 0xAA555000, 0x228BFC72, 0x0BEAC0E8, 0x1E10AA60],
+    'nRF54LM20': [0, 0x4F54500B, 0x00000000, 0x22AFFC52, 0x0BE0C0E8, 0x3E10AA60],
     # ST sort by GUID
     'ST F407/429 HS': [0x1100, 0x4F54281A, 0, 0x229ED590, 0x03F403E8, 0x17F00030],
     'ST F207/F407/411/429 FS': [0x1200, 0x4F54281A, 0, 0x229DCD20, 0x020001E8, 0x0FF08030],
diff --git a/src/portable/synopsys/dwc2/dwc2_nrf.h b/src/portable/synopsys/dwc2/dwc2_nrf.h
index 067bf39cc..fc9cd18bc 100644
--- a/src/portable/synopsys/dwc2/dwc2_nrf.h
+++ b/src/portable/synopsys/dwc2/dwc2_nrf.h
@@ -2,7 +2,6 @@
  * The MIT License (MIT)
  *
  * Copyright (c) 2025 Ha Thach (tinyusb.org)
- * Copyright (c) 2026, Gabriel Koppenstein
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -23,6 +22,9 @@
  * THE SOFTWARE.
  *
  * This file is part of the TinyUSB stack.
+ *
+ * Modification
+ * - Gabriel Koppenstein add nRF54LM20 support
  */
 #ifndef TUSB_DWC2_NRF_H
 #define TUSB_DWC2_NRF_H
@@ -33,18 +35,18 @@
 
 // Use the auto-resolving peripheral pointer (respects TrustZone secure/non-secure mapping)
 #if defined(NRF54LM20A_ENGA_XXAA)
-  #define _DWC2_NRF_REG_BASE ((uintptr_t) NRF_USBHSCORE)
+  #define DWC2_REG_BASE ((uintptr_t)NRF_USBHSCORE)
 #else
-  #define _DWC2_NRF_REG_BASE ((uintptr_t) NRF_USBHSCORE0)
+  #define DWC2_REG_BASE ((uintptr_t)NRF_USBHSCORE0)
 #endif
 
 static const dwc2_controller_t _dwc2_controller[] = {
-  { .reg_base = _DWC2_NRF_REG_BASE, .irqnum = USBHS_IRQn, .ep_count = 16, .ep_fifo_size = 12160 },
+  {.reg_base = DWC2_REG_BASE, .irqnum = USBHS_IRQn, .ep_count = 16, .otg_dfifo_depth = 3072},
 };
 
 TU_ATTR_ALWAYS_INLINE static inline void dwc2_int_set(uint8_t rhport, tusb_role_t role, bool enabled) {
-  (void) rhport;
-  (void) role;
+  (void)rhport;
+  (void)role;
   if (enabled) {
     NVIC_EnableIRQ(USBHS_IRQn);
   } else {
@@ -59,32 +61,38 @@ TU_ATTR_ALWAYS_INLINE static inline void dwc2_remote_wakeup_delay(void) {
 }
 
 // MCU specific PHY init, called BEFORE core reset
-TU_ATTR_ALWAYS_INLINE static inline void dwc2_phy_init(dwc2_regs_t* dwc2, uint8_t hs_phy_type) {
+TU_ATTR_ALWAYS_INLINE static inline void dwc2_phy_init(dwc2_regs_t *dwc2, uint8_t hs_phy_type) {
   (void)dwc2;
   (void)hs_phy_type;
 }
 
 // MCU specific PHY deinit, disable PHY power
-TU_ATTR_ALWAYS_INLINE static inline void dwc2_phy_deinit(dwc2_regs_t* dwc2, uint8_t hs_phy_type) {
+TU_ATTR_ALWAYS_INLINE static inline void dwc2_phy_deinit(dwc2_regs_t *dwc2, uint8_t hs_phy_type) {
   (void)dwc2;
   (void)hs_phy_type;
 }
 
 // MCU specific PHY update, it is called AFTER init() and core reset
-TU_ATTR_ALWAYS_INLINE static inline void dwc2_phy_update(dwc2_regs_t* dwc2, uint8_t hs_phy_type) {
+TU_ATTR_ALWAYS_INLINE static inline void dwc2_phy_update(dwc2_regs_t *dwc2, uint8_t hs_phy_type) {
   (void)dwc2;
   (void)hs_phy_type;
 }
 
 // nRF54 Cortex-M33 has no D-cache, provide no-op stubs for DMA mode
-TU_ATTR_ALWAYS_INLINE static inline bool dwc2_dcache_clean(const void* addr, uint32_t data_size) {
-  (void)addr; (void)data_size; return true;
+TU_ATTR_ALWAYS_INLINE static inline bool dwc2_dcache_clean(const void *addr, uint32_t data_size) {
+  (void)addr;
+  (void)data_size;
+  return true;
 }
-TU_ATTR_ALWAYS_INLINE static inline bool dwc2_dcache_invalidate(const void* addr, uint32_t data_size) {
-  (void)addr; (void)data_size; return true;
+TU_ATTR_ALWAYS_INLINE static inline bool dwc2_dcache_invalidate(const void *addr, uint32_t data_size) {
+  (void)addr;
+  (void)data_size;
+  return true;
 }
-TU_ATTR_ALWAYS_INLINE static inline bool dwc2_dcache_clean_invalidate(const void* addr, uint32_t data_size) {
-  (void)addr; (void)data_size; return true;
+TU_ATTR_ALWAYS_INLINE static inline bool dwc2_dcache_clean_invalidate(const void *addr, uint32_t data_size) {
+  (void)addr;
+  (void)data_size;
+  return true;
 }
 
 #endif
diff --git a/src/portable/synopsys/dwc2/dwc2_stm32.h b/src/portable/synopsys/dwc2/dwc2_stm32.h
index 259ad21b9..5f6e98224 100644
--- a/src/portable/synopsys/dwc2/dwc2_stm32.h
+++ b/src/portable/synopsys/dwc2/dwc2_stm32.h
@@ -31,36 +31,36 @@
 extern "C" {
 #endif
 
-// EP_MAX       : Max number of bi-directional endpoints including EP0
-// EP_FIFO_SIZE : Size of dedicated USB SRAM
+// EP_MAX          : Max number of bi-directional endpoints including EP0
+// DFIFO_DEPTH_FS/HS : DFIFO depth in 32-bit words (OTG_DFIFO_DEPTH)
 #if CFG_TUSB_MCU == OPT_MCU_STM32F1
   #include "stm32f1xx.h"
   #define EP_MAX_FS       4
-  #define EP_FIFO_SIZE_FS 1280
+  #define DFIFO_DEPTH_FS 320
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32F2
   #include "stm32f2xx.h"
   #define EP_MAX_FS       USB_OTG_FS_MAX_IN_ENDPOINTS
-  #define EP_FIFO_SIZE_FS USB_OTG_FS_TOTAL_FIFO_SIZE
+  #define DFIFO_DEPTH_FS  320
 
   #define EP_MAX_HS       USB_OTG_HS_MAX_IN_ENDPOINTS
-  #define EP_FIFO_SIZE_HS USB_OTG_HS_TOTAL_FIFO_SIZE
+  #define DFIFO_DEPTH_HS  1024
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32F4
   #include "stm32f4xx.h"
   #define EP_MAX_FS       USB_OTG_FS_MAX_IN_ENDPOINTS
-  #define EP_FIFO_SIZE_FS USB_OTG_FS_TOTAL_FIFO_SIZE
+  #define DFIFO_DEPTH_FS  320
 
   #define EP_MAX_HS       USB_OTG_HS_MAX_IN_ENDPOINTS
-  #define EP_FIFO_SIZE_HS USB_OTG_HS_TOTAL_FIFO_SIZE
+  #define DFIFO_DEPTH_HS  1024
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32H7
   #include "stm32h7xx.h"
   #define EP_MAX_FS       9
-  #define EP_FIFO_SIZE_FS 4096
+  #define DFIFO_DEPTH_FS 1024
 
   #define EP_MAX_HS       9
-  #define EP_FIFO_SIZE_HS 4096
+  #define DFIFO_DEPTH_HS 1024
 
   // NOTE: H7 with only 1 USB port: H72x / H73x / H7Ax / H7Bx
   // USB_OTG_FS_PERIPH_BASE and OTG_FS_IRQn not defined
@@ -72,18 +72,18 @@ extern "C" {
 #elif CFG_TUSB_MCU == OPT_MCU_STM32H7RS
   #include "stm32h7rsxx.h"
   #define EP_MAX_FS       6
-  #define EP_FIFO_SIZE_FS 1280
+  #define DFIFO_DEPTH_FS 320
 
   #define EP_MAX_HS       9
-  #define EP_FIFO_SIZE_HS 4096
+  #define DFIFO_DEPTH_HS 1024
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32N6
   #include "stm32n6xx.h"
   #define EP_MAX_FS       9
-  #define EP_FIFO_SIZE_FS 4096
+  #define DFIFO_DEPTH_FS 1024
 
   #define EP_MAX_HS       9
-  #define EP_FIFO_SIZE_HS 4096
+  #define DFIFO_DEPTH_HS 1024
 
   #define USB_OTG_FS_PERIPH_BASE    USB1_OTG_HS_BASE
   #define OTG_FS_IRQn               USB1_OTG_HS_IRQn
@@ -94,15 +94,15 @@ extern "C" {
 #elif CFG_TUSB_MCU == OPT_MCU_STM32F7
   #include "stm32f7xx.h"
   #define EP_MAX_FS       6
-  #define EP_FIFO_SIZE_FS 1280
+  #define DFIFO_DEPTH_FS 320
 
   #define EP_MAX_HS       9
-  #define EP_FIFO_SIZE_HS 4096
+  #define DFIFO_DEPTH_HS 1024
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32L4
   #include "stm32l4xx.h"
   #define EP_MAX_FS       6
-  #define EP_FIFO_SIZE_FS 1280
+  #define DFIFO_DEPTH_FS 320
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32U5
   #include "stm32u5xx.h"
@@ -110,11 +110,11 @@ extern "C" {
   #ifdef USB_OTG_FS
     #define USB_OTG_FS_PERIPH_BASE    USB_OTG_FS_BASE
     #define EP_MAX_FS                 6
-    #define EP_FIFO_SIZE_FS           1280
+    #define DFIFO_DEPTH_FS           1280
   #else
     #define USB_OTG_HS_PERIPH_BASE    USB_OTG_HS_BASE
     #define EP_MAX_HS                 9
-    #define EP_FIFO_SIZE_HS           4096
+    #define DFIFO_DEPTH_HS           4096
   #endif
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32WBA
@@ -131,7 +131,7 @@ extern "C" {
   #define USB_OTG_HS_PERIPH_BASE    USB_OTG_HS_BASE_NS
   #define OTG_HS_IRQn               USB_OTG_HS_IRQn
   #define EP_MAX_HS                 9
-  #define EP_FIFO_SIZE_HS           4096
+  #define DFIFO_DEPTH_HS           4096
 #else
   #error "Unsupported MCUs"
 #endif
@@ -147,11 +147,11 @@ extern "C" {
 // - Port0 to OTG_FS, and Port1 to OTG_HS
 static const dwc2_controller_t _dwc2_controller[] = {
     #ifdef USB_OTG_FS_PERIPH_BASE
-    { .reg_base = USB_OTG_FS_PERIPH_BASE, .irqnum = OTG_FS_IRQn, .ep_count = EP_MAX_FS, .ep_fifo_size = EP_FIFO_SIZE_FS },
+    { .reg_base = USB_OTG_FS_PERIPH_BASE, .irqnum = OTG_FS_IRQn, .ep_count = EP_MAX_FS, .otg_dfifo_depth = DFIFO_DEPTH_FS },
     #endif
 
     #ifdef USB_OTG_HS_PERIPH_BASE
-    { .reg_base = USB_OTG_HS_PERIPH_BASE, .irqnum = OTG_HS_IRQn, .ep_count = EP_MAX_HS, .ep_fifo_size = EP_FIFO_SIZE_HS },
+    { .reg_base = USB_OTG_HS_PERIPH_BASE, .irqnum = OTG_HS_IRQn, .ep_count = EP_MAX_HS, .otg_dfifo_depth = DFIFO_DEPTH_HS },
     #endif
 };
 
diff --git a/src/portable/synopsys/dwc2/dwc2_type.h b/src/portable/synopsys/dwc2/dwc2_type.h
index 596bd0b34..7c03a4a91 100644
--- a/src/portable/synopsys/dwc2/dwc2_type.h
+++ b/src/portable/synopsys/dwc2/dwc2_type.h
@@ -47,7 +47,7 @@ typedef struct
   uint32_t  irqnum;
   uint8_t   ep_count;
   uint8_t   ep_in_count;
-  uint32_t  ep_fifo_size;
+  uint16_t  otg_dfifo_depth; // total SPRAM in 32-bit words = ghwcfg3.dfifo_depth + EP_LOC_CNT
 }dwc2_controller_t;
 
 // DWC OTG HW Release versions
@@ -63,6 +63,7 @@ typedef struct
 #define DWC2_CORE_REV_4_00a   0x4f54400a
 #define DWC2_CORE_REV_4_11a   0x4f54411a
 #define DWC2_CORE_REV_4_20a   0x4f54420a
+#define DWC2_CORE_REV_5_00b   0x4F54500b
 #define DWC2_FS_IOT_REV_1_00a 0x5531100a
 #define DWC2_HS_IOT_REV_1_00a 0x5532100a
 #define DWC2_CORE_REV_MASK    0x0000ffff
diff --git a/src/portable/synopsys/dwc2/dwc2_xmc.h b/src/portable/synopsys/dwc2/dwc2_xmc.h
index aca3873df..b946444ee 100644
--- a/src/portable/synopsys/dwc2/dwc2_xmc.h
+++ b/src/portable/synopsys/dwc2/dwc2_xmc.h
@@ -39,7 +39,7 @@
 static const dwc2_controller_t _dwc2_controller[] =
 {
   // Note: XMC has some custom control registers before DWC registers
-  { .reg_base = USB0_BASE, .irqnum = USB0_0_IRQn, .ep_count = DWC2_EP_MAX, .ep_fifo_size = 2048 }
+  { .reg_base = USB0_BASE, .irqnum = USB0_0_IRQn, .ep_count = DWC2_EP_MAX, .otg_dfifo_depth = 512 }
 };
 
 TU_ATTR_ALWAYS_INLINE
diff --git a/src/portable/synopsys/dwc2/hcd_dwc2.c b/src/portable/synopsys/dwc2/hcd_dwc2.c
index e12e44a41..cd2ddf572 100644
--- a/src/portable/synopsys/dwc2/hcd_dwc2.c
+++ b/src/portable/synopsys/dwc2/hcd_dwc2.c
@@ -323,9 +323,9 @@ TU_ATTR_ALWAYS_INLINE static inline uint8_t cal_next_pid(uint8_t pid, uint8_t pa
   We allocated TX FIFO from top to bottom (using top pointer), this to allow the RX FIFO to grow dynamically which is
   possible since the free space is located between the RX and TX FIFOs.
 
-   ----------------- ep_fifo_size
-  |    HCDMAn    |
-  |--------------|-- gdfifocfg.EPINFOBASE (max is ghwcfg3.dfifo_depth)
+   ----------------- otg_dfifo_depth
+  |    HCDMAn    |   (DMA only, sized per runtime DMA mode)
+  |--------------|-- gdfifocfg.EPINFOBASE (= gdfifocfg.GDFIFOCfg)
   | Non-Periodic |
   |   TX FIFO    |
   |--------------|--- GNPTXFSIZ.addr (fixed size)
@@ -358,15 +358,22 @@ static void dfifo_host_init(uint8_t rhport, bool is_hs_phy) {
 
   // Scatter/Gather DMA mode is not yet supported. Buffer DMA only need 1 words per channel
   const bool is_dma = dma_host_enabled(dwc2);
-  uint16_t dfifo_top = dwc2_controller->ep_fifo_size/4;
+  uint16_t dfifo_top = dwc2_controller->otg_dfifo_depth;
   if (is_dma) {
     dfifo_top -= ghwcfg2.num_host_ch;
   }
 
   // fixed allocation for now, improve later:
-  // - ptx_largest is limited to 256 for FS since most FS core only has 1024 bytes total
-  uint32_t nptx_largest = is_hs_phy ? TUSB_EPSIZE_BULK_HS / 4 : TUSB_EPSIZE_BULK_FS / 4;
-  uint32_t ptx_largest  = is_hs_phy ? TUSB_EPSIZE_ISO_HS_MAX / 4 : 256 / 4;
+  // - ptx_largest is limited to 64 words for FS since most FS core only has 256-320 words total
+  uint32_t nptx_largest;
+  uint32_t ptx_largest;
+  if (is_hs_phy) {
+    nptx_largest = TUSB_EPSIZE_BULK_HS / 4;
+    ptx_largest = TUSB_EPSIZE_ISO_HS_MAX / 4;
+  } else {
+    nptx_largest = TUSB_EPSIZE_BULK_FS / 4;
+    ptx_largest = 256 / 4;
+  }
 
   uint16_t nptxfsiz = 2 * nptx_largest;
   uint16_t rxfsiz = 2 * (ptx_largest + 2) + ghwcfg2.num_host_ch;