/*
 * Copyright 2021 Max Planck Institute for Software Systems, and
 * National University of Singapore
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#pragma once

#include <stdint.h>

#include <list>
#include <vector>

#include <simbricks/nicbm/nicbm.h>

typedef uint32_t reg_t;
typedef uint64_t addr_t;
typedef uint16_t ptr_t;

#define REG_FW_ID 0x0000
#define REG_FW_VER 0x0004
#define REG_BOARD_ID 0x0008
#define REG_BOARD_VER 0x000C
#define REG_PHC_COUNT 0x0010
#define REG_PHC_OFFSET 0x0014
#define REG_PHC_STRIDE 0x0018
#define REG_IF_COUNT 0x0020
#define REG_IF_STRIDE 0x0024
#define REG_IF_CSR_OFFSET 0x002C

#define IF_FEATURE_RSS (1 << 0)
#define IF_FEATURE_PTP_TS (1 << 4)
#define IF_FEATURE_TX_CSUM (1 << 8)
#define IF_FEATURE_RX_CSUM (1 << 9)
#define IF_FEATURE_RX_HASH (1 << 10)

#define PHC_REG_FEATURES 0x0200
#define PHC_REG_PTP_CUR_SEC_L 0x0218
#define PHC_REG_PTP_CUR_SEC_H 0x021C
#define PHC_REG_PTP_SET_FNS 0x0230
#define PHC_REG_PTP_SET_NS 0x0234
#define PHC_REG_PTP_SET_SEC_L 0x0238
#define PHC_REG_PTP_SET_SEC_H 0x023C

#define IF_REG_IF_ID 0x80000
#define IF_REG_IF_FEATURES 0x80004
#define IF_REG_EVENT_QUEUE_COUNT 0x80010
#define IF_REG_EVENT_QUEUE_OFFSET 0x80014
#define IF_REG_TX_QUEUE_COUNT 0x80020
#define IF_REG_TX_QUEUE_OFFSET 0x80024
#define IF_REG_TX_CPL_QUEUE_COUNT 0x80028
#define IF_REG_TX_CPL_QUEUE_OFFSET 0x8002C
#define IF_REG_RX_QUEUE_COUNT 0x80030
#define IF_REG_RX_QUEUE_OFFSET 0x80034
#define IF_REG_RX_CPL_QUEUE_COUNT 0x80038
#define IF_REG_RX_CPL_QUEUE_OFFSET 0x8003C
#define IF_REG_PORT_COUNT 0x80040
#define IF_REG_PORT_OFFSET 0x80044
#define IF_REG_PORT_STRIDE 0x80048

#define QUEUE_ACTIVE_MASK 0x80000000
#define QUEUE_ARM_MASK 0x80000000
#define QUEUE_CONT_MASK 0x40000000

#define EVENT_QUEUE_BASE_ADDR_REG 0x100000
#define EVENT_QUEUE_ACTIVE_LOG_SIZE_REG 0x100008
#define EVENT_QUEUE_INTERRUPT_INDEX_REG 0x10000C
#define EVENT_QUEUE_HEAD_PTR_REG 0x100010
#define EVENT_QUEUE_TAIL_PTR_REG 0x100018

#define TX_QUEUE_BASE_ADDR_REG 0x200000
#define TX_QUEUE_ACTIVE_LOG_SIZE_REG 0x200008
#define TX_QUEUE_CPL_QUEUE_INDEX_REG 0x20000C
#define TX_QUEUE_HEAD_PTR_REG 0x200010
#define TX_QUEUE_TAIL_PTR_REG 0x200018

#define TX_CPL_QUEUE_BASE_ADDR_REG 0x400000
#define TX_CPL_QUEUE_ACTIVE_LOG_SIZE_REG 0x400008
#define TX_CPL_QUEUE_INTERRUPT_INDEX_REG 0x40000C
#define TX_CPL_QUEUE_HEAD_PTR_REG 0x400010
#define TX_CPL_QUEUE_TAIL_PTR_REG 0x400018

#define RX_QUEUE_BASE_ADDR_REG 0x600000
#define RX_QUEUE_ACTIVE_LOG_SIZE_REG 0x600008
#define RX_QUEUE_CPL_QUEUE_INDEX_REG 0x60000C
#define RX_QUEUE_HEAD_PTR_REG 0x600010
#define RX_QUEUE_TAIL_PTR_REG 0x600018

#define RX_CPL_QUEUE_BASE_ADDR_REG 0x700000
#define RX_CPL_QUEUE_ACTIVE_LOG_SIZE_REG 0x700008
#define RX_CPL_QUEUE_INTERRUPT_INDEX_REG 0x70000C
#define RX_CPL_QUEUE_HEAD_PTR_REG 0x700010
#define RX_CPL_QUEUE_TAIL_PTR_REG 0x700018

#define PORT_REG_PORT_ID 0x800000
#define PORT_REG_PORT_FEATURES 0x800004
#define PORT_REG_PORT_MTU 0x800008
#define PORT_REG_SCHED_COUNT 0x800010
#define PORT_REG_SCHED_OFFSET 0x800014
#define PORT_REG_SCHED_STRIDE 0x800018
#define PORT_REG_SCHED_TYPE 0x80001C
#define PORT_REG_SCHED_ENABLE 0x800040
#define PORT_REG_RSS_MASK 0x800080

#define PORT_QUEUE_ENABLE 0x900000

namespace corundum {

#define DESC_SIZE 16
#define CPL_SIZE 32
#define EVENT_SIZE 32
#define MAX_DMA_LEN 2048

class DescRing;

struct Desc {
  uint16_t rsvd0;
  uint16_t tx_csum_cmd;
  uint32_t len;
  uint64_t addr;
} __attribute__((packed));

struct Cpl {
  uint16_t queue;
  uint16_t index;
  uint16_t len;
  uint16_t rsvd0;
  uint32_t ts_ns;
  uint16_t ts_s;
  uint16_t rx_csum;
  uint32_t rx_hash;
  uint8_t rx_hash_type;
  uint8_t rsvd1;
  uint8_t rsvd2;
  uint8_t rsvd3;
  uint32_t rsvd4;
  uint32_t rsvd5;
} __attribute__((packed));

#define EVENT_TYPE_TX_CPL 0x0000
#define EVENT_TYPE_RX_CPL 0x0001

struct Event {
  uint16_t type;
  uint16_t source;
} __attribute__((packed));

struct RxData {
  size_t len;
  uint8_t data[MAX_DMA_LEN];
};

#define DMA_TYPE_DESC 0
#define DMA_TYPE_MEM 1
#define DMA_TYPE_TX_CPL 2
#define DMA_TYPE_RX_CPL 3
#define DMA_TYPE_EVENT 4

struct DMAOp : public nicbm::DMAOp {
  DMAOp() {
    data_ = databuf;
  }

  uint8_t type;
  DescRing *ring;
  RxData *rx_data;
  uint64_t tag;
  uint8_t databuf[MAX_DMA_LEN];
};

class DescRing {
 public:
  DescRing();
  ~DescRing();

  addr_t dmaAddr();
  size_t sizeLog();
  unsigned index();
  ptr_t headPtr();
  ptr_t tailPtr();

  void setDMALower(uint32_t addr);
  void setDMAUpper(uint32_t addr);
  void setSizeLog(size_t size_log);
  void setIndex(unsigned index);
  virtual void setHeadPtr(ptr_t ptr);
  void setTailPtr(ptr_t ptr);

  virtual void dmaDone(DMAOp *op) = 0;

 protected:
  bool empty();
  bool full();
  bool updatePtr(ptr_t ptr, bool head);

  addr_t _dmaAddr;
  size_t _sizeLog;
  size_t _size;
  size_t _sizeMask;
  unsigned _index;
  ptr_t _headPtr;
  ptr_t _tailPtr;
  ptr_t _currHead;
  ptr_t _currTail;
  bool active;
  bool armed;
  std::vector<bool> cplDma;
};

class EventRing : public DescRing {
 public:
  EventRing();
  ~EventRing();

  void dmaDone(DMAOp *op) override;
  void issueEvent(unsigned type, unsigned source);
};

class CplRing : public DescRing {
 public:
  explicit CplRing(EventRing *eventRing);
  ~CplRing();

  void dmaDone(DMAOp *op) override;
  void complete(unsigned index, size_t len, bool tx);

 private:
  struct CplData {
    unsigned index;
    size_t len;
    bool tx;
  };
  EventRing *eventRing;
  std::list<CplData> pending;
};

class TxRing : public DescRing {
 public:
  explicit TxRing(CplRing *cplRing);
  ~TxRing();

  void setHeadPtr(ptr_t ptr) override;
  void dmaDone(DMAOp *op) override;

 private:
  CplRing *txCplRing;
};

class RxRing : public DescRing {
 public:
  explicit RxRing(CplRing *cplRing);
  ~RxRing();

  void dmaDone(DMAOp *op) override;
  void rx(RxData *rx_data);

 private:
  CplRing *rxCplRing;
};

class Port {
 public:
  Port();
  ~Port();

  unsigned id();
  unsigned features();
  size_t mtu();
  size_t schedCount();
  addr_t schedOffset();
  addr_t schedStride();
  unsigned schedType();
  unsigned rssMask();

  void setId(unsigned id);
  void setFeatures(unsigned features);
  void setMtu(size_t mtu);
  void setSchedCount(size_t count);
  void setSchedOffset(addr_t offset);
  void setSchedStride(addr_t stride);
  void setSchedType(unsigned type);
  void setRssMask(unsigned mask);
  void schedEnable();
  void schedDisable();
  void queueEnable();
  void queueDisable();

 private:
  unsigned _id;
  unsigned _features;
  size_t _mtu;
  size_t _schedCount;
  addr_t _schedOffset;
  addr_t _schedStride;
  unsigned _schedType;
  unsigned _rssMask;
  bool _schedEnable;
  bool _queueEnable;
};

class Corundum : public nicbm::SimpleDevice<reg_t> {
 public:
  Corundum();
  ~Corundum();

  void SetupIntro(struct SimbricksProtoPcieDevIntro &di) override;
  reg_t RegRead(uint8_t bar, addr_t addr) override;
  void RegWrite(uint8_t bar, addr_t addr, reg_t val) override;
  void DmaComplete(nicbm::DMAOp &op) override;
  void EthRx(uint8_t port, const void *data, size_t len) override;

 private:
  EventRing eventRing;
  TxRing txRing;
  CplRing txCplRing;
  RxRing rxRing;
  CplRing rxCplRing;
  Port port;
  uint32_t features;
};

}  // namespace corundum
