hw/dv/dpi/usbdpi/usbdpi.h - 3p/lowrisc/opentitan - Git at Google

 // Copyright lowRISC contributors.
 // Licensed under the Apache License, Version 2.0, see LICENSE for details.
 // SPDX-License-Identifier: Apache-2.0

 #ifndef OPENTITAN_HW_DV_DPI_USBDPI_USBDPI_H_
 #define OPENTITAN_HW_DV_DPI_USBDPI_USBDPI_H_

 #define TOOL_VERILATOR 1
 #define TOOL_INCISIVE 0

 #include <assert.h>
 #include <limits.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #if USBDPI_STANDALONE
 // For stricter compilation checks, and building faster standalone
 typedef uint32_t svBitVecVal;
 #else
 #include <svdpi.h>
 #endif
 #include "usb_monitor.h"
 #include "usb_transfer.h"
 #include "usbdpi_stream.h"

 // Shall we employ a proper simulation of the frame interval (1ms)?
 // TODO - until such time as we can perform multiple control transfers in a
 //        single bus frame, this is impractical because the simulation takes too
 //        long and is apt to time out
 #define FULL_FRAME 0

 // How many bits in our frame
 //
 //   (frames on a Full Speed USB link are 1ms, with 12Mbps signalling, but the
 //    USB device supports only data transfers of up to 64 bytes, so a 1ms
 //    frame interval makes the simulation needlessly long)
 #if FULL_FRAME
 #define FRAME_INTERVAL 12000  // 12Mbps, 1ms frame time
 #else
 #define FRAME_INTERVAL 6000  // 0.5ms
 #endif

 // How many bits after start to assert VBUS
 #define SENSE_AT 20 * 8

 // Logging level (parameter to module)
 #define LOG_MON 0x01  // USB monitor logging (packet level)
 #define LOG_BIT 0x08  // bit level

 // Error insertion
 #define INSERT_ERR_CRC 0
 #define INSERT_ERR_PID 0
 #define INSERT_ERR_BITSTUFF 0
 #define INSERT_ERR_DATA_TOGGLE 0

 // Endpoints used during top-level tests
 #define ENDPOINT_ZERO 0         // Endpoint Zero (for the Default Control Pipe)
 #define ENDPOINT_SERIAL0 1      // For basic serial communications test
 #define ENDPOINT_SERIAL1 2      // Second serial channel
 #define ENDPOINT_ISOCHRONOUS 3  // For basic testing of Isochronous transfers
 #define ENDPOINT_UNIMPLEMENTED \
   15  // For testing of response to unimplemented
       // endpoints

 #define D2P_BITS 11
 #define D2P_DP 1024
 #define D2P_DP_EN 512
 #define D2P_DN 256
 #define D2P_DN_EN 128
 #define D2P_D 64
 #define D2P_D_EN 32
 #define D2P_SE0 16
 #define D2P_TX_USE_D_SE0 8
 #define D2P_DPPU 4
 #define D2P_DNPU 2
 #define D2P_RX_ENABLE 1
 // Either pullup (dp/dn swapped if the pullup is on DN)
 #define D2P_PU (D2P_DPPU | D2P_DNPU)

 #define P2D_SENSE 1
 #define P2D_DN 2
 #define P2D_DP 4
 #define P2D_D 8

 /* Remember these go LSB first */

 /* Sync is KJKJKJKK */
 #define USB_SYNC 0x2AU

 /* USB Packet IDentifiers */
 #define USB_PID_OUT 0xE1U
 #define USB_PID_IN 0x69U
 #define USB_PID_SOF 0xA5U
 #define USB_PID_SETUP 0x2DU
 #define USB_PID_DATA0 0xC3U
 #define USB_PID_DATA1 0x4BU
 #define USB_PID_ACK 0xD2U
 #define USB_PID_NAK 0x5AU
 #define USB_PID_STALL 0x1EU
 #define USB_PID_NYET 0x96U
 #define USB_PID_PING 0xB4U

 /* USB Standard Request Codes */
 #define USB_REQ_GET_STATUS 0x00U
 #define USB_REQ_CLEAR_FEATURE 0x01U
 #define USB_REQ_SET_FEATURE 0x03U
 #define USB_REQ_SET_ADDRESS 0x05U
 #define USB_REQ_GET_DESCRIPTOR 0x06U
 #define USB_REQ_SET_DESCRIPTOR 0x07U
 #define USB_REQ_GET_CONFIGURATION 0x08U
 #define USB_REQ_SET_CONFIGURATION 0x09U
 #define USB_REQ_GET_INTERFACE 0x0AU
 #define USB_REQ_SET_INTERFACE 0x0BU
 #define USB_REQ_SYNCH_FRAME 0x0CU

 /* USB Descriptor Types */
 #define USB_DESC_TYPE_DEVICE 0x01U
 #define USB_DESC_TYPE_CONFIGURATION 0x02U
 #define USB_DESC_TYPE_STRING 0x03U
 #define USB_DESC_TYPE_INTERFACE 0x04U
 #define USB_DESC_TYPE_ENDPOINT 0x05U
 #define USB_DESC_TYPE_DEVICE_QUALIFIER 0x06U
 #define USB_DESC_TYPE_OTHER_SPEED_CONFIG 0x07U
 #define USB_DESC_TYPE_INTERFACE_POWER 0x08U

 // Device address to be used for the USBDEV IP block
 #define USBDEV_ADDRESS 2

 // Unknown device address (check USBDEV ignores traffic to other devices)
 #define UKDEV_ADDRESS 6

 // Maximum number of endpoints implemented by the USBDEV IP
 #define USBDEV_MAX_ENDPOINTS 12U

 // Maximum number of endpoints supported by the DPI model
 #define USBDPI_MAX_ENDPOINTS 16U

 // Maximum number of bidirection LFSR-generated byte streams that may be
 // supported simultaneously
 #define USBDPI_MAX_STREAMS (USBDPI_MAX_ENDPOINTS - 1U)

 // Maximum number of simultaneous transfer descriptors
 //   (The host model may simply avoid polling for further IN transfers
 //    whilst there are no further desciptors available)
 #define USBDPI_MAX_TRANSFERS 0x10U

 // Time intervals for common transactions, in bits
 // (allowing for bit stuffing and bus turnaround etc; for setting timeouts)
 #define USBDPI_INTERVAL_SETUP_STAGE 200U

 // Return the time at which the given number of bit intervals shall have elapsed
 #define USBDPI_TIMEOUT(ctx, bits) ((ctx)->tick_bits + (bits))

 // Maximum length of test status message
 #define USBDPI_MAX_TEST_MSG_LEN 80U

 // Vendor-specific commands used for test framework
 #define USBDPI_VENDOR_TEST_CONFIG 0x7CU
 #define USBDPI_VENDOR_TEST_STATUS 0x7EU

 // Next DATAx PID to be used (transmission) or expected (reception)
 #define DATA_TOGGLE_ADVANCE(pid) \
   ((pid) == USB_PID_DATA1 ? USB_PID_DATA0 : USB_PID_DATA1)

 #ifdef __cplusplus
 extern "C" {
 #endif

 // USBDPI driver states
 typedef enum {
   ST_IDLE = 0,
   ST_SEND = 1,
   ST_GET = 2,
   ST_SYNC = 3,
   ST_EOP = 4,
   ST_EOP0 = 5
 } usbdpi_drv_state_t;

 // Test steps
 typedef enum {

   STEP_BUS_RESET = 0u,
   STEP_SET_DEVICE_ADDRESS,
   STEP_GET_DEVICE_DESCRIPTOR,
   STEP_GET_CONFIG_DESCRIPTOR,
   STEP_GET_FULL_CONFIG_DESCRIPTOR,
   STEP_SET_DEVICE_CONFIG,

   // Read test configuration
   // This is a bespoke 'vendor' command via which we inquire of the CPU
   // software what behaviour is required
   STEP_GET_TEST_CONFIG,
   // Report test status (pass/failure) to the CPU software
   STEP_SET_TEST_STATUS,

   // usbdev_test
   STEP_FIRST_READ,
   STEP_READ_BAUD,
   STEP_SECOND_READ,
   STEP_SET_BAUD,
   STEP_THIRD_READ,
   STEP_TEST_ISO1,
   STEP_TEST_ISO2,
   STEP_ENDPT_UNIMPL_SETUP,
   STEP_ENDPT_UNIMPL_OUT,
   STEP_ENDPT_UNIMPL_IN,
   STEP_DEVICE_UK_SETUP,
   STEP_IDLE_START,
   STEP_IDLE_END = STEP_IDLE_START + 4,

   // usbdev_stream_test
   STEP_STREAM_SERVICE = 0x20u,

   // Disconnect the device and stop
   STEP_BUS_DISCONNECT = 0x7fu
 } usbdpi_test_step_t;

 // Host states
 typedef enum {
   HS_STARTFRAME = 0,
   HS_WAITACK = 1,
   HS_SET_DATASTAGE = 2,

   HS_DS_RXDATA = 3,
   HS_DS_SENDACK = 4,
   HS_DONEDADR = 5,
   HS_REQDATA = 6,
   HS_WAITDATA = 7,
   HS_SENDACK = 8,
   HS_WAIT_PKT = 9,
   HS_ACKIFDATA = 10,
   HS_SENDHI = 11,
   HS_EMPTYDATA = 12,
   HS_WAITACK2 = 13,
   HS_STREAMOUT = 14,
   HS_STREAMIN = 15,
   HS_NEXTFRAME = 16
 } usbdpi_host_state_t;

 typedef enum usbdpi_bus_state {
   kUsbIdle = 0,
   kUsbControlSetup,
   kUsbControlSetupAck,
   kUsbControlDataOut,
   kUsbControlDataOutAck,
   kUsbControlStatusInToken,
   kUsbControlStatusInData,
   kUsbControlStatusInAck,

   kUsbControlDataInToken,
   kUsbControlDataInData,
   kUsbControlDataInAck,
   kUsbControlStatusOut,
   kUsbControlStatusOutAck,
   kUsbIsoToken,
   kUsbIsoDataIn,
   kUsbIsoDataOut,

   kUsbBulkOut,
   kUsbBulkOutAck,
   kUsbBulkInToken,
   kUsbBulkInData,
   kUsbBulkInAck,
 } usbdpi_bus_state_t;

 /**
  * USB DPI state information
  */
 struct usbdpi_ctx {
   // Bus signalling state
   usbdpi_bus_state_t bus_state;
   uint32_t driving;
   int linebits;
   int bit;
   int byte;
   /**
    * Test number, retrieved from the software
    */
   uint16_t test_number;
   /**
    * Test-specific arguments
    */
   uint8_t test_arg[4];
   /**
    * Test status
    * TODO - introduce enum indicating the test status, or borrow from
    *        the existing source tree; we indicate progress too in other places
    */
   uint32_t test_status;
   char test_msg[USBDPI_MAX_TEST_MSG_LEN];

   /**
    * Context for IN endpoints
    */
   struct {
     /**
      * Next DATAx PID (DATA0 or DATA1) expected from device
      */
     uint8_t next_data;
   } ep_in[USBDPI_MAX_ENDPOINTS];
   /**
    * Context for OUT endpoints
    */
   struct {
     /**
      * Next DATAx (DATA0 or DATA1) to be transmitted; advanced when ACKed
      * and reset after SETUP packet transmitted
      */
     uint8_t next_data;
   } ep_out[USBDPI_MAX_ENDPOINTS];

   /**
    * Number of data streams being used
    */
   uint8_t nstreams;
   /**
    * Stream number of next stream to attempt IN transfers
    */
   uint8_t stream_in;
   /**
    * Stream number of next stream to attempt OUT transfers
    */
   uint8_t stream_out;
   /**
    * Context for streaming data test (usbdev_stream_test)
    */
   usbdpi_stream_t stream[USBDPI_MAX_STREAMS];

   // Diagnostic logging and bus monitoring
   int loglevel;
   char mon_pathname[FILENAME_MAX];

   /**
    * USB monitor instance
    */
   usb_monitor_ctx_t *mon;

   /**
    * Host controller state
    */
   usbdpi_host_state_t hostSt;
   /**
    * Transfer currently being received from the DUT (NULL iff none)
    */
   usbdpi_transfer_t *recving;
   /***
    * Transfer currently being sent to the DUT (NULL iff none)
    */
   usbdpi_transfer_t *sending;

   uint32_t last_pu;
   uint8_t lastrxpid;

   /**
    * Count of clock cycles
    */
   uint32_t tick;
   /**
    * Current time in USB bit intervals
    */
   uint32_t tick_bits;
   /**
    * End time of recovery interval (following device attachment)
    */
   uint32_t recovery_time;

   /**
    * Test step number
    */
   usbdpi_test_step_t step;

   // Bus framing
   // Note: USB frame numbers are transmitted as 11-bit fields [0,0x7ffU]
   uint16_t frame;
   uint16_t framepend;

   /**
    * Time at which the current frame started (bit intervals)
    */
   uint32_t frame_start;

   /**
    * Wait timeout for current operation (bit intervals)
    */
   uint32_t wait;

   /**
    * DPI driver state
    */
   usbdpi_drv_state_t state;

   int baudrate_set_successfully;

   /**
    * Device address currently assigned to the DUT
    */
   uint8_t dev_address;
   /**
    * Length of configuration descriptor
    */
   uint16_t cfg_desc_len;
   /**
    * Linked-list of free transfer descriptors
    */
   usbdpi_transfer_t *free;

   /**
    * Small pool of transfer descriptors
    */
   usbdpi_transfer_t transfer_pool[USBDPI_MAX_TRANSFERS];
 };

 /**
  * Create a USB DPI instance, returning a 'chandle' for later use
  */
 void *usbdpi_create(const char *name, int loglevel);
 /**
  * Close a USB DPI instance
  */
 void usbdpi_close(void *ctx_void);

 /**
  * Respond to device outputs
  */
 void usbdpi_device_to_host(void *ctx_void, const svBitVecVal *usb_d2p);

 /**
  * Update DPI model outputs
  */
 uint8_t usbdpi_host_to_device(void *ctx_void, const svBitVecVal *usb_d2p);

 /**
  * Return DPI model diagnostic information for viewing in waveforms
  */
 void usbdpi_diags(void *ctx_void, svBitVecVal *diags);

 /**
  * Calculate 5-bit CRC used to check token packets
  */
 uint32_t CRC5(uint32_t dwInput, int iBitcnt);

 /**
  * Calculate 16-bit CRC used to check data fields
  */
 uint32_t CRC16(const uint8_t *data, int bytes);

 #ifdef __cplusplus
 }
 #endif

 #endif  // OPENTITAN_HW_DV_DPI_USBDPI_USBDPI_H_
	// Copyright lowRISC contributors.
	// Licensed under the Apache License, Version 2.0, see LICENSE for details.
	// SPDX-License-Identifier: Apache-2.0

	#ifndef OPENTITAN_HW_DV_DPI_USBDPI_USBDPI_H_
	#define OPENTITAN_HW_DV_DPI_USBDPI_USBDPI_H_

	#define TOOL_VERILATOR 1
	#define TOOL_INCISIVE 0

	#include <assert.h>
	#include <limits.h>
	#include <stdint.h>
	#include <stdio.h>
	#include <stdlib.h>
	#if USBDPI_STANDALONE
	// For stricter compilation checks, and building faster standalone
	typedef uint32_t svBitVecVal;
	#else
	#include <svdpi.h>
	#endif
	#include "usb_monitor.h"
	#include "usb_transfer.h"
	#include "usbdpi_stream.h"

	// Shall we employ a proper simulation of the frame interval (1ms)?
	// TODO - until such time as we can perform multiple control transfers in a
	// single bus frame, this is impractical because the simulation takes too
	// long and is apt to time out
	#define FULL_FRAME 0

	// How many bits in our frame
	//
	// (frames on a Full Speed USB link are 1ms, with 12Mbps signalling, but the
	// USB device supports only data transfers of up to 64 bytes, so a 1ms
	// frame interval makes the simulation needlessly long)
	#if FULL_FRAME
	#define FRAME_INTERVAL 12000 // 12Mbps, 1ms frame time
	#else
	#define FRAME_INTERVAL 6000 // 0.5ms
	#endif

	// How many bits after start to assert VBUS
	#define SENSE_AT 20 * 8

	// Logging level (parameter to module)
	#define LOG_MON 0x01 // USB monitor logging (packet level)
	#define LOG_BIT 0x08 // bit level

	// Error insertion
	#define INSERT_ERR_CRC 0
	#define INSERT_ERR_PID 0
	#define INSERT_ERR_BITSTUFF 0
	#define INSERT_ERR_DATA_TOGGLE 0

	// Endpoints used during top-level tests
	#define ENDPOINT_ZERO 0 // Endpoint Zero (for the Default Control Pipe)
	#define ENDPOINT_SERIAL0 1 // For basic serial communications test
	#define ENDPOINT_SERIAL1 2 // Second serial channel
	#define ENDPOINT_ISOCHRONOUS 3 // For basic testing of Isochronous transfers
	#define ENDPOINT_UNIMPLEMENTED \
	15 // For testing of response to unimplemented
	// endpoints

	#define D2P_BITS 11
	#define D2P_DP 1024
	#define D2P_DP_EN 512
	#define D2P_DN 256
	#define D2P_DN_EN 128
	#define D2P_D 64
	#define D2P_D_EN 32
	#define D2P_SE0 16
	#define D2P_TX_USE_D_SE0 8
	#define D2P_DPPU 4
	#define D2P_DNPU 2
	#define D2P_RX_ENABLE 1
	// Either pullup (dp/dn swapped if the pullup is on DN)
	#define D2P_PU (D2P_DPPU \| D2P_DNPU)

	#define P2D_SENSE 1
	#define P2D_DN 2
	#define P2D_DP 4
	#define P2D_D 8

	/* Remember these go LSB first */

	/* Sync is KJKJKJKK */
	#define USB_SYNC 0x2AU

	/* USB Packet IDentifiers */
	#define USB_PID_OUT 0xE1U
	#define USB_PID_IN 0x69U
	#define USB_PID_SOF 0xA5U
	#define USB_PID_SETUP 0x2DU
	#define USB_PID_DATA0 0xC3U
	#define USB_PID_DATA1 0x4BU
	#define USB_PID_ACK 0xD2U
	#define USB_PID_NAK 0x5AU
	#define USB_PID_STALL 0x1EU
	#define USB_PID_NYET 0x96U
	#define USB_PID_PING 0xB4U

	/* USB Standard Request Codes */
	#define USB_REQ_GET_STATUS 0x00U
	#define USB_REQ_CLEAR_FEATURE 0x01U
	#define USB_REQ_SET_FEATURE 0x03U
	#define USB_REQ_SET_ADDRESS 0x05U
	#define USB_REQ_GET_DESCRIPTOR 0x06U
	#define USB_REQ_SET_DESCRIPTOR 0x07U
	#define USB_REQ_GET_CONFIGURATION 0x08U
	#define USB_REQ_SET_CONFIGURATION 0x09U
	#define USB_REQ_GET_INTERFACE 0x0AU
	#define USB_REQ_SET_INTERFACE 0x0BU
	#define USB_REQ_SYNCH_FRAME 0x0CU

	/* USB Descriptor Types */
	#define USB_DESC_TYPE_DEVICE 0x01U
	#define USB_DESC_TYPE_CONFIGURATION 0x02U
	#define USB_DESC_TYPE_STRING 0x03U
	#define USB_DESC_TYPE_INTERFACE 0x04U
	#define USB_DESC_TYPE_ENDPOINT 0x05U
	#define USB_DESC_TYPE_DEVICE_QUALIFIER 0x06U
	#define USB_DESC_TYPE_OTHER_SPEED_CONFIG 0x07U
	#define USB_DESC_TYPE_INTERFACE_POWER 0x08U

	// Device address to be used for the USBDEV IP block
	#define USBDEV_ADDRESS 2

	// Unknown device address (check USBDEV ignores traffic to other devices)
	#define UKDEV_ADDRESS 6

	// Maximum number of endpoints implemented by the USBDEV IP
	#define USBDEV_MAX_ENDPOINTS 12U

	// Maximum number of endpoints supported by the DPI model
	#define USBDPI_MAX_ENDPOINTS 16U

	// Maximum number of bidirection LFSR-generated byte streams that may be
	// supported simultaneously
	#define USBDPI_MAX_STREAMS (USBDPI_MAX_ENDPOINTS - 1U)

	// Maximum number of simultaneous transfer descriptors
	// (The host model may simply avoid polling for further IN transfers
	// whilst there are no further desciptors available)
	#define USBDPI_MAX_TRANSFERS 0x10U

	// Time intervals for common transactions, in bits
	// (allowing for bit stuffing and bus turnaround etc; for setting timeouts)
	#define USBDPI_INTERVAL_SETUP_STAGE 200U

	// Return the time at which the given number of bit intervals shall have elapsed
	#define USBDPI_TIMEOUT(ctx, bits) ((ctx)->tick_bits + (bits))

	// Maximum length of test status message
	#define USBDPI_MAX_TEST_MSG_LEN 80U

	// Vendor-specific commands used for test framework
	#define USBDPI_VENDOR_TEST_CONFIG 0x7CU
	#define USBDPI_VENDOR_TEST_STATUS 0x7EU

	// Next DATAx PID to be used (transmission) or expected (reception)
	#define DATA_TOGGLE_ADVANCE(pid) \
	((pid) == USB_PID_DATA1 ? USB_PID_DATA0 : USB_PID_DATA1)

	#ifdef __cplusplus
	extern "C" {
	#endif

	// USBDPI driver states
	typedef enum {
	ST_IDLE = 0,
	ST_SEND = 1,
	ST_GET = 2,
	ST_SYNC = 3,
	ST_EOP = 4,
	ST_EOP0 = 5
	} usbdpi_drv_state_t;

	// Test steps
	typedef enum {

	STEP_BUS_RESET = 0u,
	STEP_SET_DEVICE_ADDRESS,
	STEP_GET_DEVICE_DESCRIPTOR,
	STEP_GET_CONFIG_DESCRIPTOR,
	STEP_GET_FULL_CONFIG_DESCRIPTOR,
	STEP_SET_DEVICE_CONFIG,

	// Read test configuration
	// This is a bespoke 'vendor' command via which we inquire of the CPU
	// software what behaviour is required
	STEP_GET_TEST_CONFIG,
	// Report test status (pass/failure) to the CPU software
	STEP_SET_TEST_STATUS,

	// usbdev_test
	STEP_FIRST_READ,
	STEP_READ_BAUD,
	STEP_SECOND_READ,
	STEP_SET_BAUD,
	STEP_THIRD_READ,
	STEP_TEST_ISO1,
	STEP_TEST_ISO2,
	STEP_ENDPT_UNIMPL_SETUP,
	STEP_ENDPT_UNIMPL_OUT,
	STEP_ENDPT_UNIMPL_IN,
	STEP_DEVICE_UK_SETUP,
	STEP_IDLE_START,
	STEP_IDLE_END = STEP_IDLE_START + 4,

	// usbdev_stream_test
	STEP_STREAM_SERVICE = 0x20u,

	// Disconnect the device and stop
	STEP_BUS_DISCONNECT = 0x7fu
	} usbdpi_test_step_t;

	// Host states
	typedef enum {
	HS_STARTFRAME = 0,
	HS_WAITACK = 1,
	HS_SET_DATASTAGE = 2,

	HS_DS_RXDATA = 3,
	HS_DS_SENDACK = 4,
	HS_DONEDADR = 5,
	HS_REQDATA = 6,
	HS_WAITDATA = 7,
	HS_SENDACK = 8,
	HS_WAIT_PKT = 9,
	HS_ACKIFDATA = 10,
	HS_SENDHI = 11,
	HS_EMPTYDATA = 12,
	HS_WAITACK2 = 13,
	HS_STREAMOUT = 14,
	HS_STREAMIN = 15,
	HS_NEXTFRAME = 16
	} usbdpi_host_state_t;

	typedef enum usbdpi_bus_state {
	kUsbIdle = 0,
	kUsbControlSetup,
	kUsbControlSetupAck,
	kUsbControlDataOut,
	kUsbControlDataOutAck,
	kUsbControlStatusInToken,
	kUsbControlStatusInData,
	kUsbControlStatusInAck,

	kUsbControlDataInToken,
	kUsbControlDataInData,
	kUsbControlDataInAck,
	kUsbControlStatusOut,
	kUsbControlStatusOutAck,
	kUsbIsoToken,
	kUsbIsoDataIn,
	kUsbIsoDataOut,

	kUsbBulkOut,
	kUsbBulkOutAck,
	kUsbBulkInToken,
	kUsbBulkInData,
	kUsbBulkInAck,
	} usbdpi_bus_state_t;

	/**
	* USB DPI state information
	*/
	struct usbdpi_ctx {
	// Bus signalling state
	usbdpi_bus_state_t bus_state;
	uint32_t driving;
	int linebits;
	int bit;
	int byte;
	/**
	* Test number, retrieved from the software
	*/
	uint16_t test_number;
	/**
	* Test-specific arguments
	*/
	uint8_t test_arg[4];
	/**
	* Test status
	* TODO - introduce enum indicating the test status, or borrow from
	* the existing source tree; we indicate progress too in other places
	*/
	uint32_t test_status;
	char test_msg[USBDPI_MAX_TEST_MSG_LEN];

	/**
	* Context for IN endpoints
	*/
	struct {
	/**
	* Next DATAx PID (DATA0 or DATA1) expected from device
	*/
	uint8_t next_data;
	} ep_in[USBDPI_MAX_ENDPOINTS];
	/**
	* Context for OUT endpoints
	*/
	struct {
	/**
	* Next DATAx (DATA0 or DATA1) to be transmitted; advanced when ACKed
	* and reset after SETUP packet transmitted
	*/
	uint8_t next_data;
	} ep_out[USBDPI_MAX_ENDPOINTS];

	/**
	* Number of data streams being used
	*/
	uint8_t nstreams;
	/**
	* Stream number of next stream to attempt IN transfers
	*/
	uint8_t stream_in;
	/**
	* Stream number of next stream to attempt OUT transfers
	*/
	uint8_t stream_out;
	/**
	* Context for streaming data test (usbdev_stream_test)
	*/
	usbdpi_stream_t stream[USBDPI_MAX_STREAMS];

	// Diagnostic logging and bus monitoring
	int loglevel;
	char mon_pathname[FILENAME_MAX];

	/**
	* USB monitor instance
	*/
	usb_monitor_ctx_t *mon;

	/**
	* Host controller state
	*/
	usbdpi_host_state_t hostSt;
	/**
	* Transfer currently being received from the DUT (NULL iff none)
	*/
	usbdpi_transfer_t *recving;
	/***
	* Transfer currently being sent to the DUT (NULL iff none)
	*/
	usbdpi_transfer_t *sending;

	uint32_t last_pu;
	uint8_t lastrxpid;

	/**
	* Count of clock cycles
	*/
	uint32_t tick;
	/**
	* Current time in USB bit intervals
	*/
	uint32_t tick_bits;
	/**
	* End time of recovery interval (following device attachment)
	*/
	uint32_t recovery_time;

	/**
	* Test step number
	*/
	usbdpi_test_step_t step;

	// Bus framing
	// Note: USB frame numbers are transmitted as 11-bit fields [0,0x7ffU]
	uint16_t frame;
	uint16_t framepend;

	/**
	* Time at which the current frame started (bit intervals)
	*/
	uint32_t frame_start;

	/**
	* Wait timeout for current operation (bit intervals)
	*/
	uint32_t wait;

	/**
	* DPI driver state
	*/
	usbdpi_drv_state_t state;

	int baudrate_set_successfully;

	/**
	* Device address currently assigned to the DUT
	*/
	uint8_t dev_address;
	/**
	* Length of configuration descriptor
	*/
	uint16_t cfg_desc_len;
	/**
	* Linked-list of free transfer descriptors
	*/
	usbdpi_transfer_t *free;

	/**
	* Small pool of transfer descriptors
	*/
	usbdpi_transfer_t transfer_pool[USBDPI_MAX_TRANSFERS];
	};

	/**
	* Create a USB DPI instance, returning a 'chandle' for later use
	*/
	void usbdpi_create(const char name, int loglevel);
	/**
	* Close a USB DPI instance
	*/
	void usbdpi_close(void *ctx_void);

	/**
	* Respond to device outputs
	*/
	void usbdpi_device_to_host(void ctx_void, const svBitVecVal usb_d2p);

	/**
	* Update DPI model outputs
	*/
	uint8_t usbdpi_host_to_device(void ctx_void, const svBitVecVal usb_d2p);

	/**
	* Return DPI model diagnostic information for viewing in waveforms
	*/
	void usbdpi_diags(void ctx_void, svBitVecVal diags);

	/**
	* Calculate 5-bit CRC used to check token packets
	*/
	uint32_t CRC5(uint32_t dwInput, int iBitcnt);

	/**
	* Calculate 16-bit CRC used to check data fields
	*/
	uint32_t CRC16(const uint8_t *data, int bytes);

	#ifdef __cplusplus
	}
	#endif

	#endif // OPENTITAN_HW_DV_DPI_USBDPI_USBDPI_H_