Improve USB device detection

Author: hikalium

DEBUGGING.md

@@ -0,0 +1,9 @@
+# Debugging tips
+
+## usb
+
+- https://github.com/qemu/qemu/blob/master/docs/usb2.txt
+```
+device_add usb-mouse,id=usbmouse_hotplug,port=4
+device_del usbmouse_hotplug
+```

qemu.mk

@@ -9,7 +9,7 @@ PORT_VNC=5
 QEMU_ARGS_COMMON_HW_CONFIG=\
 		-machine q35,nvdimm=on -cpu qemu64 -smp 4 \
 		-bios $(OVMF) \
-		-device qemu-xhci -device usb-mouse \
+		-device qemu-xhci -device usb-mouse,id=usbmouse1 \
 		-netdev user,id=usbnet0 -device usb-net,netdev=usbnet0 \
 		-object filter-dump,id=f2,netdev=usbnet0,file=dump_usb_nic.dat \
 		-m 2G,slots=2,maxmem=4G \

src/hpet.cc

@@ -84,6 +84,9 @@ void HPET::BusyWaitMicroSecond(uint64_t microsec) {
 uint64_t HPET::GetFemtosecondPerCount() {
   return femtosecond_per_count_;
 }
+uint64_t HPET::GetCountPerSecond() {
+  return 1e15 / femtosecond_per_count_;
+}
 
 void HPET::Print() {
   PutStringAndHex("HPET at", registers_);

src/hpet.h

@@ -20,6 +20,7 @@ class HPET {
                   HPET::TimerConfig flags);
   uint64_t ReadMainCounterValue();
   uint64_t GetFemtosecondPerCount();
+  uint64_t GetCountPerSecond();
   void BusyWait(uint64_t ms);
   void BusyWaitMicroSecond(uint64_t);
   void Print(void);

src/xhci.cc

@@ -153,15 +153,14 @@ void Controller::ResetPort(int port) {
   while ((ReadPORTSC(port) & kPortSCBitPortReset)) {
     // wait
   }
-  port_state_[port] = kNeedsSlotAssignment;
-  port_is_initializing_[port] = true;
+  port_state_[port] = kDisabled;
+  port_is_initializing_[port] = false;
 }
 
 void Controller::DisablePort(int port) {
   PutStringAndHex("Disable port", port);
   WritePORTSC(port, 2);
-  port_state_[port] = kDisabled;
-  port_is_initializing_[port] = false;
+  ResetPort(port);
 }
 
 class Controller::EndpointContext {
@@ -712,6 +711,7 @@ void Controller::HandleAddressDeviceCompleted(int slot) {
   uint8_t* buf = AllocMemoryForMappedIO<uint8_t*>(kSizeOfDescriptorBuffer);
   descriptor_buffers_[slot] = buf;
   port_is_initializing_[slot_info_[slot].port] = false;
+  kprintf("AddressDevice for port %d completed\n", slot_info_[slot].port);
   RequestDeviceDescriptor(slot, SlotInfo::kWaitingForDeviceDescriptor);
 }
 
@@ -858,24 +858,25 @@ void Controller::HandleTransferEvent(BasicTRB& e) {
   }
 }
 
+static void PrintPortSCValue(uint32_t portsc) {
+  PutStringAndHex("PORTSC", portsc);
+  PutString("PortSC: ");
+  PutHex64ZeroFilled(portsc);
+  PutString(" (");
+  PutString((portsc & (1 << 9)) ? "1" : "0");
+  PutString((portsc & (1 << 0)) ? "1" : "0");
+  PutString((portsc & (1 << 1)) ? "1" : "0");
+  PutString((portsc & (1 << 4)) ? "1" : "0");
+  PutString(") ");
+  // 7.2.2.1.1 Default USB Speed ID Mapping
+  PutString("Speed=0x");
+  PutHex64(GetBits<13, 10>(portsc));
+  PutString("\n");
+}
 void Controller::PrintPortSC() {
   for (int slot = 1; slot <= num_of_slots_enabled_; slot++) {
-    uint32_t portsc = ReadPORTSC(slot);
     PutStringAndHex("Port", slot);
-    PutStringAndHex("PORTSC", portsc);
-    PutString("PortSC: ");
-    PutHex64ZeroFilled(portsc);
-    PutString(" (");
-    PutString((portsc & (1 << 9)) ? "1" : "0");
-    PutString((portsc & (1 << 0)) ? "1" : "0");
-    PutString((portsc & (1 << 1)) ? "1" : "0");
-    PutString((portsc & (1 << 4)) ? "1" : "0");
-    PutString(") ");
-    // 7.2.2.1.1 Default USB Speed ID Mapping
-    PutString("Speed=0x");
-    PutHex64(GetBits<13, 10>(portsc));
-
-    PutString("\n");
+    PrintPortSCValue(ReadPORTSC(slot));
   }
 }
 void Controller::PrintUSBSTS() {
@@ -891,6 +892,7 @@ void Controller::PrintUSBSTS() {
 }
 
 void Controller::CheckPortAndInitiateProcess() {
+  HPET& hpet = HPET::GetInstance();
   for (int i = 0; i < kMaxNumOfPorts; i++) {
     if (port_state_[i] == kNeedsSlotAssignment) {
       port_state_[i] = kWaitingForSlotAssignment;
@@ -903,16 +905,28 @@ void Controller::CheckPortAndInitiateProcess() {
       enable_slot_trb.control = (BasicTRB::kTRBTypeEnableSlotCommand << 10);
       cmd_ring_->Push();
       NotifyHostControllerDoorbell();
+      kprintf("Sent slot assignment request for port%d\n", i);
       return;
     }
   }
   for (int i = 0; i < kMaxNumOfPorts; i++) {
-    if (port_is_initializing_[i])
-      return;
+    if (!port_is_initializing_[i]) {
+      continue;
+    }
+    if (port_init_deadline_ < hpet.ReadMainCounterValue()) {
+      kprintf("Port init deadline exceeded for port %d\n", i);
+      DisablePort(i);
+    }
+    return;
   }
   for (int i = 0; i < kMaxNumOfPorts; i++) {
     if (port_state_[i] == kAttachedUSB2) {
       ResetPort(i);
+      port_state_[i] = kNeedsSlotAssignment;
+      port_is_initializing_[i] = true;
+      kprintf("Port init deadline for port %d is set.\n", i);
+      port_init_deadline_ =
+          hpet.ReadMainCounterValue() + hpet.GetCountPerSecond();
       return;
     }
   }
@@ -990,13 +1004,27 @@ void Controller::PollEvents() {
   }
   for (int port = 1; port <= max_ports_; port++) {
     uint32_t portsc = ReadPORTSC(port);
+    if (!(portsc & kPortSCBitCurrentConnectStatus)) {
+      // Device is disconnected
+      if (port_state_[port] == kDisconnected) {
+        continue;
+      }
+      DisablePort(port);
+      port_state_[port] = kDisconnected;
+      kprintf("port %d disconnected\n", port);
+      PrintPortSCValue(ReadPORTSC(port));
+      continue;
+    }
     if (port_state_[port] == kDisconnected &&
         (portsc & kPortSCBitCurrentConnectStatus)) {
+      kprintf("port %d connected\n", port);
+      PrintPortSCValue(ReadPORTSC(port));
       port_state_[port] = kAttached;
     }
     if (port_state_[port] == kAttached &&
         !(portsc & kPortSCBitPortEnableDisable) &&
         !(portsc & kPortSCBitPortReset) && ReadPORTSCLinkState(port) == 7) {
+      kprintf("port %d: kAttachedUSB2\n", port);
       port_state_[port] = kAttachedUSB2;
     }
   }

src/xhci.h

@@ -274,8 +274,11 @@ class Controller {
   static constexpr uint32_t kUSBCMDMaskRunStop = 0b01;
   static constexpr uint32_t kUSBCMDMaskHCReset = 0b10;
 
+  /*
+   * PORTSC values
+   */
   static constexpr uint32_t kPortSCBitCurrentConnectStatus = 1 << 0;
-  static constexpr uint32_t kPortSCBitPortEnableDisable = 1 << 1;
+  static constexpr uint32_t kPortSCBitPortEnableDisable = 1 << 1; // RW1CS
   static constexpr uint32_t kPortSCBitPortReset = 1 << 4;
   static constexpr uint32_t kPortSCBitPortLinkState = 0b111100000;
   static constexpr uint32_t kPortSCPortLinkStateShift = 5;
@@ -404,6 +407,7 @@ class Controller {
   bool controller_reset_requested_ = false;
   int max_num_of_scratch_pad_buf_entries_;
   volatile uint64_t* scratchpad_buffer_array_;
+  uint64_t port_init_deadline_;
 };
 
 }  // namespace XHCI