dwc2: fix EP0 DMA setup race condition

Signed-off-by: HiFiPhile <[email protected]>

1 files changed, 15 insertions, 14 deletions

diff --git a/src/portable/synopsys/dwc2/dcd_dwc2.c b/src/portable/synopsys/dwc2/dcd_dwc2.c
index 23fe671d4..1c119eef4 100644
--- a/src/portable/synopsys/dwc2/dcd_dwc2.c
+++ b/src/portable/synopsys/dwc2/dcd_dwc2.c
@@ -73,8 +73,9 @@ typedef struct {
 
 static dcd_data_t _dcd_data;
 
-CFG_TUD_MEM_SECTION static struct {
-  TUD_EPBUF_DEF(setup_packet, 8);
+CFG_TUD_MEM_SECTION static union {
+  TUD_EPBUF_DEF(setup_buffer, 8);
+  tusb_control_request_t setup_packet;
 } _dcd_usbbuf;
 
 static tud_configure_dwc2_t _tud_cfg = CFG_TUD_CONFIGURE_DWC2_DEFAULT;
@@ -138,7 +139,7 @@ static void dma_setup_prepare(uint8_t rhport) {
 
   // Receive only 1 packet
   dwc2->epout[0].doeptsiz = (1 << DOEPTSIZ_STUPCNT_Pos) | (1 << DOEPTSIZ_PKTCNT_Pos) | (8 << DOEPTSIZ_XFRSIZ_Pos);
-  dwc2->epout[0].doepdma = (uintptr_t) _dcd_usbbuf.setup_packet;
+  dwc2->epout[0].doepdma = (uintptr_t) _dcd_usbbuf.setup_buffer;
   dwc2->epout[0].doepctl |= DOEPCTL_EPENA | DOEPCTL_USBAEP;
 }
 
@@ -896,7 +897,7 @@ static void handle_rxflvl_irq(uint8_t rhport) {
 
     case GRXSTS_PKTSTS_SETUP_RX: {
       // Setup packet received
-      uint32_t* setup = (uint32_t*)(uintptr_t) _dcd_usbbuf.setup_packet;
+      uint32_t* setup = (uint32_t*)(uintptr_t) _dcd_usbbuf.setup_buffer;
       // We can receive up to three setup packets in succession, but only the last one is valid.
       setup[0] = (*rx_fifo);
       setup[1] = (*rx_fifo);
@@ -956,7 +957,7 @@ static void handle_epout_slave(uint8_t rhport, uint8_t epnum, dwc2_doepint_t doe
     if (edpt_is_enabled(epin0)) {
       edpt_disable(rhport, 0x80, false);
     }
-    dcd_event_setup_received(rhport, _dcd_usbbuf.setup_packet, true);
+    dcd_event_setup_received(rhport, _dcd_usbbuf.setup_buffer, true);
     return;
   }
 
@@ -1021,9 +1022,13 @@ static void handle_epout_dma(uint8_t rhport, uint8_t epnum, dwc2_doepint_t doepi
     if (edpt_is_enabled(epin0)) {
       edpt_disable(rhport, 0x80, false);
     }
-    dma_setup_prepare(rhport);
-    dcd_dcache_invalidate(_dcd_usbbuf.setup_packet, 8);
-    dcd_event_setup_received(rhport, _dcd_usbbuf.setup_packet, true);
+    dcd_dcache_invalidate(_dcd_usbbuf.setup_buffer, 8);
+    dcd_event_setup_received(rhport, _dcd_usbbuf.setup_buffer, true);
+
+    // Prepare EP0 for next setup if this setup has no data stage
+    if (_dcd_usbbuf.setup_packet.wLength == 0) {
+      dma_setup_prepare(rhport);
+    }
     return;
   }
 
@@ -1044,9 +1049,8 @@ static void handle_epout_dma(uint8_t rhport, uint8_t epnum, dwc2_doepint_t doepi
         const uint16_t remain = tsiz.xfer_size;
         xfer->total_len -= remain;
 
-        // this is ZLP, so prepare EP0 for next setup
-        // TODO use status phase rx
-        if(epnum == 0 && xfer->total_len == 0) {
+        // prepare EP0 for next setup
+        if(epnum == 0) {
           dma_setup_prepare(rhport);
         }
 
@@ -1065,9 +1069,6 @@ static void handle_epin_dma(uint8_t rhport, uint8_t epnum, dwc2_diepint_t diepin
       // EP0 can only handle one packet. Schedule another packet to be transmitted.
       edpt_schedule_packets(rhport, epnum, TUSB_DIR_IN);
     } else {
-      if(epnum == 0) {
-        dma_setup_prepare(rhport);
-      }
       dcd_event_xfer_complete(rhport, epnum | TUSB_DIR_IN_MASK, xfer->total_len, XFER_RESULT_SUCCESS, true);
     }
   }