qca_7k_common.h

  1/* SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause */
  2/*
  3 *   Copyright (c) 2011, 2012, Atheros Communications Inc.
  4 *   Copyright (c) 2014, I2SE GmbH
  5 */
  6
  7/*   Atheros Ethernet framing. Every Ethernet frame is surrounded by an atheros
  8 *   frame while transmitted over a serial channel.
  9 */
 10
 11#ifndef _QCA_FRAMING_H
 12#define _QCA_FRAMING_H
 13
 14#include <linux/if_ether.h>
 15#include <linux/if_vlan.h>
 16#include <linux/types.h>
 17
 18/* Frame is currently being received */
 19#define QCAFRM_GATHER 0
 20
 21/*  No header byte while expecting it */
 22#define QCAFRM_NOHEAD (QCAFRM_ERR_BASE - 1)
 23
 24/* No tailer byte while expecting it */
 25#define QCAFRM_NOTAIL (QCAFRM_ERR_BASE - 2)
 26
 27/* Frame length is invalid */
 28#define QCAFRM_INVLEN (QCAFRM_ERR_BASE - 3)
 29
 30/* Frame length is invalid */
 31#define QCAFRM_INVFRAME (QCAFRM_ERR_BASE - 4)
 32
 33/* Min/Max Ethernet MTU: 46/1500 */
 34#define QCAFRM_MIN_MTU (ETH_ZLEN - ETH_HLEN)
 35#define QCAFRM_MAX_MTU ETH_DATA_LEN
 36
 37/* Min/Max frame lengths */
 38#define QCAFRM_MIN_LEN (QCAFRM_MIN_MTU + ETH_HLEN)
 39#define QCAFRM_MAX_LEN (QCAFRM_MAX_MTU + VLAN_ETH_HLEN)
 40
 41/* QCA7K header len */
 42#define QCAFRM_HEADER_LEN 8
 43
 44/* QCA7K footer len */
 45#define QCAFRM_FOOTER_LEN 2
 46
 47/* QCA7K Framing. */
 48#define QCAFRM_ERR_BASE -1000
 49
 50enum qcafrm_state {
 51	/* HW length is only available on SPI */
 52	QCAFRM_HW_LEN0 = 0x8000,
 53	QCAFRM_HW_LEN1 = QCAFRM_HW_LEN0 - 1,
 54	QCAFRM_HW_LEN2 = QCAFRM_HW_LEN1 - 1,
 55	QCAFRM_HW_LEN3 = QCAFRM_HW_LEN2 - 1,
 56
 57	/*  Waiting first 0xAA of header */
 58	QCAFRM_WAIT_AA1 = QCAFRM_HW_LEN3 - 1,
 59
 60	/*  Waiting second 0xAA of header */
 61	QCAFRM_WAIT_AA2 = QCAFRM_WAIT_AA1 - 1,
 62
 63	/*  Waiting third 0xAA of header */
 64	QCAFRM_WAIT_AA3 = QCAFRM_WAIT_AA2 - 1,
 65
 66	/*  Waiting fourth 0xAA of header */
 67	QCAFRM_WAIT_AA4 = QCAFRM_WAIT_AA3 - 1,
 68
 69	/*  Waiting Byte 0-1 of length (litte endian) */
 70	QCAFRM_WAIT_LEN_BYTE0 = QCAFRM_WAIT_AA4 - 1,
 71	QCAFRM_WAIT_LEN_BYTE1 = QCAFRM_WAIT_AA4 - 2,
 72
 73	/* Reserved bytes */
 74	QCAFRM_WAIT_RSVD_BYTE1 = QCAFRM_WAIT_AA4 - 3,
 75	QCAFRM_WAIT_RSVD_BYTE2 = QCAFRM_WAIT_AA4 - 4,
 76
 77	/*  The frame length is used as the state until
 78	 *  the end of the Ethernet frame
 79	 *  Waiting for first 0x55 of footer
 80	 */
 81	QCAFRM_WAIT_551 = 1,
 82
 83	/*  Waiting for second 0x55 of footer */
 84	QCAFRM_WAIT_552 = QCAFRM_WAIT_551 - 1
 85};
 86
 87/*   Structure to maintain the frame decoding during reception. */
 88
 89struct qcafrm_handle {
 90	/*  Current decoding state */
 91	enum qcafrm_state state;
 92	/* Initial state depends on connection type */
 93	enum qcafrm_state init;
 94
 95	/* Offset in buffer (borrowed for length too) */
 96	u16 offset;
 97};
 98
 99u16 qcafrm_create_header(u8 *buf, u16 len);
100
101u16 qcafrm_create_footer(u8 *buf);
102
103static inline void qcafrm_fsm_init_spi(struct qcafrm_handle *handle)
104{
105	handle->init = QCAFRM_HW_LEN0;
106	handle->state = handle->init;
107}
108
109static inline void qcafrm_fsm_init_uart(struct qcafrm_handle *handle)
110{
111	handle->init = QCAFRM_WAIT_AA1;
112	handle->state = handle->init;
113}
114
115s32 qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_byte);
116
117#endif /* _QCA_FRAMING_H */