text: /* Intel(R) Ethernet Switch Host Interface Driver
   * Copyright(c) 2013 - 2016 Intel Corporation.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms and conditions of the GNU General Public License,
   * version 2, as published by the Free Software Foundation.
   *
   * This program is distributed in the hope it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * The full GNU General Public License is included in this distribution in
   * the file called "COPYING".
   *
   * Contact Information:
   * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
   * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
   */
  
  #ifndef _FM10K_MBX_H_
  #define _FM10K_MBX_H_
  
  /* forward declaration */
  struct fm10k_mbx_info;
  
  #include "fm10k_type.h"
  #include "fm10k_tlv.h"
  
  /* PF Mailbox Registers */
  #define FM10K_MBMEM(_n)		((_n) + 0x18000)
  #define FM10K_MBMEM_VF(_n, _m)	(((_n) * 0x10) + (_m) + 0x18000)
  #define FM10K_MBMEM_SM(_n)	((_n) + 0x18400)
  #define FM10K_MBMEM_PF(_n)	((_n) + 0x18600)
  /* XOR provides means of switching from Tx to Rx FIFO */
  #define FM10K_MBMEM_PF_XOR	(FM10K_MBMEM_SM(0) ^ FM10K_MBMEM_PF(0))
  #define FM10K_MBX(_n)		((_n) + 0x18800)
  #define FM10K_MBX_REQ				0x00000002
  #define FM10K_MBX_ACK				0x00000004
  #define FM10K_MBX_REQ_INTERRUPT			0x00000008
  #define FM10K_MBX_ACK_INTERRUPT			0x00000010
  #define FM10K_MBX_INTERRUPT_ENABLE		0x00000020
  #define FM10K_MBX_INTERRUPT_DISABLE		0x00000040
  #define FM10K_MBICR(_n)		((_n) + 0x18840)
  #define FM10K_GMBX		0x18842
  
  /* VF Mailbox Registers */
  #define FM10K_VFMBX		0x00010
  #define FM10K_VFMBMEM(_n)	((_n) + 0x00020)
  #define FM10K_VFMBMEM_LEN	16
  #define FM10K_VFMBMEM_VF_XOR	(FM10K_VFMBMEM_LEN / 2)
  
  /* Delays/timeouts */
  #define FM10K_MBX_DISCONNECT_TIMEOUT		500
  #define FM10K_MBX_POLL_DELAY			19
  #define FM10K_MBX_INT_DELAY			20
  
  /* PF/VF Mailbox state machine
   *
   * +----------+	    connect()	+----------+
   * |  CLOSED  | --------------> |  CONNECT |
   * +----------+			+----------+
   *   ^				  ^	 |
   *   | rcv:	      rcv:	  |	 | rcv:
   *   |  Connect	       Disconnect |	 |  Connect
   *   |  Disconnect     Error	  |	 |  Data
   *   |				  |	 |
   *   |				  |	 V
   * +----------+   disconnect()	+----------+
   * |DISCONNECT| <-------------- |   OPEN   |
   * +----------+			+----------+
   *
   * The diagram above describes the PF/VF mailbox state machine.  There
   * are four main states to this machine.
   * Closed: This state represents a mailbox that is in a standby state
   *	   with interrupts disabled.  In this state the mailbox should not
   *	   read the mailbox or write any data.  The only means of exiting
   *	   this state is for the system to make the connect() call for the
   *	   mailbox, it will then transition to the connect state.
   * Connect: In this state the mailbox is seeking a connection.  It will
   *	    post a connect message with no specified destination and will
   *	    wait for a reply from the other side of the mailbox.  This state
   *	    is exited when either a connect with the local mailbox as the
   *	    destination is received or when a data message is received with
   *	    a valid sequence number.
   * Open: In this state the mailbox is able to transfer data between the local
   *       entity and the remote.  It will fall back to connect in the event of
   *       receiving either an error message, or a disconnect message.  It will
   *       transition to disconnect on a call to disconnect();
   * Disconnect: In this state the mailbox is attempting to gracefully terminate
   *	       the connection.  It will do so at the first point where it knows
   *	       that the remote endpoint is either done sending, or when the
   *	       remote endpoint has fallen back into connect.
   */
  enum fm10k_mbx_state {
  	FM10K_STATE_CLOSED,
  	FM10K_STATE_CONNECT,
  	FM10K_STATE_OPEN,
  	FM10K_STATE_DISCONNECT,
  };
  
  /* PF/VF Mailbox header format
   *    3			  2		      1			  0
   *  1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
   * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   * |        Size/Err_no/CRC        | Rsvd0 | Head  | Tail  | Type  |
   * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   *
   * The layout above describes the format for the header used in the PF/VF
   * mailbox.  The header is broken out into the following fields:
   * Type: There are 4 supported message types
   *		0x8: Data header - used to transport message data
   *		0xC: Connect header - used to establish connection
   *		0xD: Disconnect header - used to tear down a connection
   *		0xE: Error header - used to address message exceptions
   * Tail: Tail index for local FIFO
   *		Tail index actually consists of two parts.  The MSB of
   *		the head is a loop tracker, it is 0 on an even numbered
   *		loop through the FIFO, and 1 on the odd numbered loops.
   *		To get the actual mailbox offset based on the tail it
   *		is necessary to add bit 3 to bit 0 and clear bit 3.  This
   *		gives us a valid range of 0x1 - 0xE.
   * Head: Head index for remote FIFO
   *		Head index follows the same format as the tail index.
   * Rsvd0: Reserved 0 portion of the mailbox header
   * CRC: Running CRC for all data since connect plus current message header
   * Size: Maximum message size - Applies only to connect headers
   *		The maximum message size is provided during connect to avoid
   *		jamming the mailbox with messages that do not fit.
   * Err_no: Error number - Applies only to error headers
   *		The error number provides an indication of the type of error
   *		experienced.
   */
  
  /* macros for retrieving and setting header values */
  #define FM10K_MSG_HDR_MASK(name) \
  	((0x1u << FM10K_MSG_##name##_SIZE) - 1)
  #define FM10K_MSG_HDR_FIELD_SET(value, name) \
  	(((u32)(value) & FM10K_MSG_HDR_MASK(name)) << FM10K_MSG_##name##_SHIFT)
  #define FM10K_MSG_HDR_FIELD_GET(value, name) \
  	((u16)((value) >> FM10K_MSG_##name##_SHIFT) & FM10K_MSG_HDR_MASK(name))
  
  /* offsets shared between all headers */
  #define FM10K_MSG_TYPE_SHIFT			0
  #define FM10K_MSG_TYPE_SIZE			4
  #define FM10K_MSG_TAIL_SHIFT			4
  #define FM10K_MSG_TAIL_SIZE			4
  #define FM10K_MSG_HEAD_SHIFT			8
  #define FM10K_MSG_HEAD_SIZE			4
  #define FM10K_MSG_RSVD0_SHIFT			12
  #define FM10K_MSG_RSVD0_SIZE			4
  
  /* offsets for data/disconnect headers */
  #define FM10K_MSG_CRC_SHIFT			16
  #define FM10K_MSG_CRC_SIZE			16
  
  /* offsets for connect headers */
  #define FM10K_MSG_CONNECT_SIZE_SHIFT		16
  #define FM10K_MSG_CONNECT_SIZE_SIZE		16
  
  /* offsets for error headers */
  #define FM10K_MSG_ERR_NO_SHIFT			16
  #define FM10K_MSG_ERR_NO_SIZE			16
  
  enum fm10k_msg_type {
  	FM10K_MSG_DATA			= 0x8,
  	FM10K_MSG_CONNECT		= 0xC,
  	FM10K_MSG_DISCONNECT		= 0xD,
  	FM10K_MSG_ERROR			= 0xE,
  };
  
  /* HNI/SM Mailbox FIFO format
   *    3                   2                   1                   0
   *  1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
   * +-------+-----------------------+-------+-----------------------+
   * | Error |      Remote Head      |Version|      Local Tail       |
   * +-------+-----------------------+-------+-----------------------+
   * |                                                               |
   * .                        Local FIFO Data                        .
   * .                                                               .
   * +-------+-----------------------+-------+-----------------------+
   *
   * The layout above describes the format for the FIFOs used by the host
   * network interface and the switch manager to communicate messages back
   * and forth.  Both the HNI and the switch maintain one such FIFO.  The
   * layout in memory has the switch manager FIFO followed immediately by
   * the HNI FIFO.  For this reason I am using just the pointer to the
   * HNI FIFO in the mailbox ops as the offset between the two is fixed.
   *
   * The header for the FIFO is broken out into the following fields:
   * Local Tail:  Offset into FIFO region for next DWORD to write.
   * Version:  Version info for mailbox, only values of 0/1 are supported.
   * Remote Head:  Offset into remote FIFO to indicate how much we have read.
   * Error: Error indication, values TBD.
   */
  
  /* version number for switch manager mailboxes */
  #define FM10K_SM_MBX_VERSION		1
  #define FM10K_SM_MBX_FIFO_LEN		(FM10K_MBMEM_PF_XOR - 1)
  
  /* offsets shared between all SM FIFO headers */
  #define FM10K_MSG_SM_TAIL_SHIFT			0
  #define FM10K_MSG_SM_TAIL_SIZE			12
  #define FM10K_MSG_SM_VER_SHIFT			12
  #define FM10K_MSG_SM_VER_SIZE			4
  #define FM10K_MSG_SM_HEAD_SHIFT			16
  #define FM10K_MSG_SM_HEAD_SIZE			12
  #define FM10K_MSG_SM_ERR_SHIFT			28
  #define FM10K_MSG_SM_ERR_SIZE			4
  
  /* All error messages returned by mailbox functions
   * The value -511 is 0xFE01 in hex.  The idea is to order the errors
   * from 0xFE01 - 0xFEFF so error codes are easily visible in the mailbox
   * messages.  This also helps to avoid error number collisions as Linux
   * doesn't appear to use error numbers 256 - 511.
   */
  #define FM10K_MBX_ERR(_n) ((_n) - 512)
  #define FM10K_MBX_ERR_NO_MBX		FM10K_MBX_ERR(0x01)
  #define FM10K_MBX_ERR_NO_SPACE		FM10K_MBX_ERR(0x03)
  #define FM10K_MBX_ERR_TAIL		FM10K_MBX_ERR(0x05)
  #define FM10K_MBX_ERR_HEAD		FM10K_MBX_ERR(0x06)
  #define FM10K_MBX_ERR_SRC		FM10K_MBX_ERR(0x08)
  #define FM10K_MBX_ERR_TYPE		FM10K_MBX_ERR(0x09)
  #define FM10K_MBX_ERR_SIZE		FM10K_MBX_ERR(0x0B)
  #define FM10K_MBX_ERR_BUSY		FM10K_MBX_ERR(0x0C)
  #define FM10K_MBX_ERR_RSVD0		FM10K_MBX_ERR(0x0E)
  #define FM10K_MBX_ERR_CRC		FM10K_MBX_ERR(0x0F)
  
  #define FM10K_MBX_CRC_SEED		0xFFFF
  
  struct fm10k_mbx_ops {
  	s32 (*connect)(struct fm10k_hw *, struct fm10k_mbx_info *);
  	void (*disconnect)(struct fm10k_hw *, struct fm10k_mbx_info *);
  	bool (*rx_ready)(struct fm10k_mbx_info *);
  	bool (*tx_ready)(struct fm10k_mbx_info *, u16);
  	bool (*tx_complete)(struct fm10k_mbx_info *);
  	s32 (*enqueue_tx)(struct fm10k_hw *, struct fm10k_mbx_info *,
  			  const u32 *);
  	s32 (*process)(struct fm10k_hw *, struct fm10k_mbx_info *);
  	s32 (*register_handlers)(struct fm10k_mbx_info *,
  				 const struct fm10k_msg_data *);
  };
  
  struct fm10k_mbx_fifo {
  	u32 *buffer;
  	u16 head;
  	u16 tail;
  	u16 size;
  };
  
  /* size of buffer to be stored in mailbox for FIFOs */
  #define FM10K_MBX_TX_BUFFER_SIZE	512
  #define FM10K_MBX_RX_BUFFER_SIZE	128
  #define FM10K_MBX_BUFFER_SIZE \
  	(FM10K_MBX_TX_BUFFER_SIZE + FM10K_MBX_RX_BUFFER_SIZE)
  
  /* minimum and maximum message size in dwords */
  #define FM10K_MBX_MSG_MAX_SIZE \
  	((FM10K_MBX_TX_BUFFER_SIZE - 1) & (FM10K_MBX_RX_BUFFER_SIZE - 1))
  #define FM10K_VFMBX_MSG_MTU	((FM10K_VFMBMEM_LEN / 2) - 1)
  
  #define FM10K_MBX_INIT_TIMEOUT	2000 /* number of retries on mailbox */
  #define FM10K_MBX_INIT_DELAY	500  /* microseconds between retries */
  
  struct fm10k_mbx_info {
  	/* function pointers for mailbox operations */
  	struct fm10k_mbx_ops ops;
  	const struct fm10k_msg_data *msg_data;
  
  	/* message FIFOs */
  	struct fm10k_mbx_fifo rx;
  	struct fm10k_mbx_fifo tx;
  
  	/* delay for handling timeouts */
  	u32 timeout;
  	u32 udelay;
  
  	/* mailbox state info */
  	u32 mbx_reg, mbmem_reg, mbx_lock, mbx_hdr;
  	u16 max_size, mbmem_len;
  	u16 tail, tail_len, pulled;
  	u16 head, head_len, pushed;
  	u16 local, remote;
  	enum fm10k_mbx_state state;
  
  	/* result of last mailbox test */
  	s32 test_result;
  
  	/* statistics */
  	u64 tx_busy;
  	u64 tx_dropped;
  	u64 tx_messages;
  	u64 tx_dwords;
  	u64 tx_mbmem_pulled;
  	u64 rx_messages;
  	u64 rx_dwords;
  	u64 rx_mbmem_pushed;
  	u64 rx_parse_err;
  
  	/* Buffer to store messages */
  	u32 buffer[FM10K_MBX_BUFFER_SIZE];
  };
  
  s32 fm10k_pfvf_mbx_init(struct fm10k_hw *, struct fm10k_mbx_info *,
  			const struct fm10k_msg_data *, u8);
  s32 fm10k_sm_mbx_init(struct fm10k_hw *, struct fm10k_mbx_info *,
  		      const struct fm10k_msg_data *);
  
  #endif /* _FM10K_MBX_H_ */
  