qca_7k_common.h (4254B)
1/* 2 * Copyright (c) 2011, 2012, Atheros Communications Inc. 3 * Copyright (c) 2014, I2SE GmbH 4 * 5 * Permission to use, copy, modify, and/or distribute this software 6 * for any purpose with or without fee is hereby granted, provided 7 * that the above copyright notice and this permission notice appear 8 * in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL 11 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED 12 * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL 13 * THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR 14 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, 16 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 17 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20/* Atheros Ethernet framing. Every Ethernet frame is surrounded by an atheros 21 * frame while transmitted over a serial channel. 22 */ 23 24#ifndef _QCA_FRAMING_H 25#define _QCA_FRAMING_H 26 27#include <linux/if_ether.h> 28#include <linux/if_vlan.h> 29#include <linux/types.h> 30 31/* Frame is currently being received */ 32#define QCAFRM_GATHER 0 33 34/* No header byte while expecting it */ 35#define QCAFRM_NOHEAD (QCAFRM_ERR_BASE - 1) 36 37/* No tailer byte while expecting it */ 38#define QCAFRM_NOTAIL (QCAFRM_ERR_BASE - 2) 39 40/* Frame length is invalid */ 41#define QCAFRM_INVLEN (QCAFRM_ERR_BASE - 3) 42 43/* Frame length is invalid */ 44#define QCAFRM_INVFRAME (QCAFRM_ERR_BASE - 4) 45 46/* Min/Max Ethernet MTU: 46/1500 */ 47#define QCAFRM_MIN_MTU (ETH_ZLEN - ETH_HLEN) 48#define QCAFRM_MAX_MTU ETH_DATA_LEN 49 50/* Min/Max frame lengths */ 51#define QCAFRM_MIN_LEN (QCAFRM_MIN_MTU + ETH_HLEN) 52#define QCAFRM_MAX_LEN (QCAFRM_MAX_MTU + VLAN_ETH_HLEN) 53 54/* QCA7K header len */ 55#define QCAFRM_HEADER_LEN 8 56 57/* QCA7K footer len */ 58#define QCAFRM_FOOTER_LEN 2 59 60/* QCA7K Framing. */ 61#define QCAFRM_ERR_BASE -1000 62 63enum qcafrm_state { 64 /* HW length is only available on SPI */ 65 QCAFRM_HW_LEN0 = 0x8000, 66 QCAFRM_HW_LEN1 = QCAFRM_HW_LEN0 - 1, 67 QCAFRM_HW_LEN2 = QCAFRM_HW_LEN1 - 1, 68 QCAFRM_HW_LEN3 = QCAFRM_HW_LEN2 - 1, 69 70 /* Waiting first 0xAA of header */ 71 QCAFRM_WAIT_AA1 = QCAFRM_HW_LEN3 - 1, 72 73 /* Waiting second 0xAA of header */ 74 QCAFRM_WAIT_AA2 = QCAFRM_WAIT_AA1 - 1, 75 76 /* Waiting third 0xAA of header */ 77 QCAFRM_WAIT_AA3 = QCAFRM_WAIT_AA2 - 1, 78 79 /* Waiting fourth 0xAA of header */ 80 QCAFRM_WAIT_AA4 = QCAFRM_WAIT_AA3 - 1, 81 82 /* Waiting Byte 0-1 of length (litte endian) */ 83 QCAFRM_WAIT_LEN_BYTE0 = QCAFRM_WAIT_AA4 - 1, 84 QCAFRM_WAIT_LEN_BYTE1 = QCAFRM_WAIT_AA4 - 2, 85 86 /* Reserved bytes */ 87 QCAFRM_WAIT_RSVD_BYTE1 = QCAFRM_WAIT_AA4 - 3, 88 QCAFRM_WAIT_RSVD_BYTE2 = QCAFRM_WAIT_AA4 - 4, 89 90 /* The frame length is used as the state until 91 * the end of the Ethernet frame 92 * Waiting for first 0x55 of footer 93 */ 94 QCAFRM_WAIT_551 = 1, 95 96 /* Waiting for second 0x55 of footer */ 97 QCAFRM_WAIT_552 = QCAFRM_WAIT_551 - 1 98}; 99 100/* Structure to maintain the frame decoding during reception. */ 101 102struct qcafrm_handle { 103 /* Current decoding state */ 104 enum qcafrm_state state; 105 /* Initial state depends on connection type */ 106 enum qcafrm_state init; 107 108 /* Offset in buffer (borrowed for length too) */ 109 u16 offset; 110 111 /* Frame length as kept by this module */ 112 u16 len; 113}; 114 115u16 qcafrm_create_header(u8 *buf, u16 len); 116 117u16 qcafrm_create_footer(u8 *buf); 118 119static inline void qcafrm_fsm_init_spi(struct qcafrm_handle *handle) 120{ 121 handle->init = QCAFRM_HW_LEN0; 122 handle->state = handle->init; 123} 124 125static inline void qcafrm_fsm_init_uart(struct qcafrm_handle *handle) 126{ 127 handle->init = QCAFRM_WAIT_AA1; 128 handle->state = handle->init; 129} 130 131/* Gather received bytes and try to extract a full Ethernet frame 132 * by following a simple state machine. 133 * 134 * Return: QCAFRM_GATHER No Ethernet frame fully received yet. 135 * QCAFRM_NOHEAD Header expected but not found. 136 * QCAFRM_INVLEN QCA7K frame length is invalid 137 * QCAFRM_NOTAIL Footer expected but not found. 138 * > 0 Number of byte in the fully received 139 * Ethernet frame 140 */ 141 142s32 qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_byte); 143 144#endif /* _QCA_FRAMING_H */