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 8 |
43 | |
44 | /* QCA7K footer len */ |
45 | #define 2 |
46 | |
47 | /* QCA7K Framing. */ |
48 | #define QCAFRM_ERR_BASE -1000 |
49 | |
50 | enum 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 | |
89 | struct 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 | |
99 | u16 (u8 *buf, u16 len); |
100 | |
101 | u16 (u8 *buf); |
102 | |
103 | static inline void qcafrm_fsm_init_spi(struct qcafrm_handle *handle) |
104 | { |
105 | handle->init = QCAFRM_HW_LEN0; |
106 | handle->state = handle->init; |
107 | } |
108 | |
109 | static inline void qcafrm_fsm_init_uart(struct qcafrm_handle *handle) |
110 | { |
111 | handle->init = QCAFRM_WAIT_AA1; |
112 | handle->state = handle->init; |
113 | } |
114 | |
115 | s32 qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_byte); |
116 | |
117 | #endif /* _QCA_FRAMING_H */ |
118 | |