diff options
Diffstat (limited to 'kernel/drivers/net/ethernet/qualcomm/qca_framing.h')
| -rw-r--r-- | kernel/drivers/net/ethernet/qualcomm/qca_framing.h | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/kernel/drivers/net/ethernet/qualcomm/qca_framing.h b/kernel/drivers/net/ethernet/qualcomm/qca_framing.h new file mode 100644 index 000000000..5d965959c --- /dev/null +++ b/kernel/drivers/net/ethernet/qualcomm/qca_framing.h @@ -0,0 +1,134 @@ +/* + * Copyright (c) 2011, 2012, Atheros Communications Inc. + * Copyright (c) 2014, I2SE GmbH + * + * Permission to use, copy, modify, and/or distribute this software + * for any purpose with or without fee is hereby granted, provided + * that the above copyright notice and this permission notice appear + * in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL + * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + * THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, + * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN + * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* Atheros Ethernet framing. Every Ethernet frame is surrounded by an atheros + * frame while transmitted over a serial channel. + */ + +#ifndef _QCA_FRAMING_H +#define _QCA_FRAMING_H + +#include <linux/if_ether.h> +#include <linux/if_vlan.h> +#include <linux/types.h> + +/* Frame is currently being received */ +#define QCAFRM_GATHER 0 + +/* No header byte while expecting it */ +#define QCAFRM_NOHEAD (QCAFRM_ERR_BASE - 1) + +/* No tailer byte while expecting it */ +#define QCAFRM_NOTAIL (QCAFRM_ERR_BASE - 2) + +/* Frame length is invalid */ +#define QCAFRM_INVLEN (QCAFRM_ERR_BASE - 3) + +/* Frame length is invalid */ +#define QCAFRM_INVFRAME (QCAFRM_ERR_BASE - 4) + +/* Min/Max Ethernet MTU */ +#define QCAFRM_ETHMINMTU 46 +#define QCAFRM_ETHMAXMTU 1500 + +/* Min/Max frame lengths */ +#define QCAFRM_ETHMINLEN (QCAFRM_ETHMINMTU + ETH_HLEN) +#define QCAFRM_ETHMAXLEN (QCAFRM_ETHMAXMTU + VLAN_ETH_HLEN) + +/* QCA7K header len */ +#define QCAFRM_HEADER_LEN 8 + +/* QCA7K footer len */ +#define QCAFRM_FOOTER_LEN 2 + +/* QCA7K Framing. */ +#define QCAFRM_ERR_BASE -1000 + +enum qcafrm_state { + QCAFRM_HW_LEN0 = 0x8000, + QCAFRM_HW_LEN1 = QCAFRM_HW_LEN0 - 1, + QCAFRM_HW_LEN2 = QCAFRM_HW_LEN1 - 1, + QCAFRM_HW_LEN3 = QCAFRM_HW_LEN2 - 1, + + /* Waiting first 0xAA of header */ + QCAFRM_WAIT_AA1 = QCAFRM_HW_LEN3 - 1, + + /* Waiting second 0xAA of header */ + QCAFRM_WAIT_AA2 = QCAFRM_WAIT_AA1 - 1, + + /* Waiting third 0xAA of header */ + QCAFRM_WAIT_AA3 = QCAFRM_WAIT_AA2 - 1, + + /* Waiting fourth 0xAA of header */ + QCAFRM_WAIT_AA4 = QCAFRM_WAIT_AA3 - 1, + + /* Waiting Byte 0-1 of length (litte endian) */ + QCAFRM_WAIT_LEN_BYTE0 = QCAFRM_WAIT_AA4 - 1, + QCAFRM_WAIT_LEN_BYTE1 = QCAFRM_WAIT_AA4 - 2, + + /* Reserved bytes */ + QCAFRM_WAIT_RSVD_BYTE1 = QCAFRM_WAIT_AA4 - 3, + QCAFRM_WAIT_RSVD_BYTE2 = QCAFRM_WAIT_AA4 - 4, + + /* The frame length is used as the state until + * the end of the Ethernet frame + * Waiting for first 0x55 of footer + */ + QCAFRM_WAIT_551 = 1, + + /* Waiting for second 0x55 of footer */ + QCAFRM_WAIT_552 = QCAFRM_WAIT_551 - 1 +}; + +/* Structure to maintain the frame decoding during reception. */ + +struct qcafrm_handle { + /* Current decoding state */ + enum qcafrm_state state; + + /* Offset in buffer (borrowed for length too) */ + s16 offset; + + /* Frame length as kept by this module */ + u16 len; +}; + +u16 qcafrm_create_header(u8 *buf, u16 len); + +u16 qcafrm_create_footer(u8 *buf); + +static inline void qcafrm_fsm_init(struct qcafrm_handle *handle) +{ + handle->state = QCAFRM_HW_LEN0; +} + +/* Gather received bytes and try to extract a full Ethernet frame + * by following a simple state machine. + * + * Return: QCAFRM_GATHER No Ethernet frame fully received yet. + * QCAFRM_NOHEAD Header expected but not found. + * QCAFRM_INVLEN QCA7K frame length is invalid + * QCAFRM_NOTAIL Footer expected but not found. + * > 0 Number of byte in the fully received + * Ethernet frame + */ + +s32 qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_byte); + +#endif /* _QCA_FRAMING_H */ |