| /* |
| * Copyright (C) 1995 Advanced RISC Machines Limited. All rights reserved. |
| * |
| * This software may be freely used, copied, modified, and distributed |
| * provided that the above copyright notice is preserved in all copies of the |
| * software. |
| */ |
| |
| /*-*-C-*- |
| * |
| * $Revision$ |
| * $Date$ |
| * |
| * |
| * Project: ANGEL |
| * |
| * Title: Definitions required for the rx and tx engines |
| */ |
| |
| #ifndef angel_rxtx_h |
| #define angel_rxtx_h |
| |
| |
| /* |
| * we need a definition for bool, which is "system" dependent |
| */ |
| #ifdef TARGET |
| # include "angel.h" |
| #else |
| # include "host.h" |
| #endif |
| |
| #include "devclnt.h" |
| |
| /* return status codes for the rx engine */ |
| typedef enum re_status { |
| RS_WAIT_PKT, |
| RS_IN_PKT, |
| RS_BAD_PKT, |
| RS_GOOD_PKT |
| } re_status; |
| |
| /* return status codes for the tx engine */ |
| typedef enum te_status { |
| TS_IDLE, |
| TS_IN_PKT, |
| TS_DONE_PKT |
| } te_status; |
| |
| |
| /* |
| * required serial definitions, they should all be <32, refer to the |
| * re_config struct comments for more details |
| */ |
| #define serial_STX (0x1c) /* data packet start */ |
| #define serial_ETX (0x1d) /* packet end */ |
| #define serial_ESC (0x1b) /* standard escape character */ |
| #define serial_XON (0x11) /* software flow control - enable transmission */ |
| #define serial_XOFF (0x13) /* software flow control - disable transmission */ |
| |
| /* |
| * All other characters are transmitted clean. If any of the above |
| * characters need to be transmitted as part of the serial data stream |
| * then the character will be preceded by the "serial_ESC" character, |
| * and then the required character transmitted (OR-ed with the |
| * "serial_ESCAPE" value, to ensure that the serial stream never has |
| * any of the exceptional characters generated by data transfers). |
| */ |
| |
| #define serial_ESCAPE (0x40) /* OR-ed with escaped characters */ |
| |
| /* bad packet error codes */ |
| typedef enum re_error { |
| RE_OKAY, |
| RE_U_STX, |
| RE_U_ETX, |
| RE_LEN, |
| RE_CRC, |
| RE_NETX, |
| RE_INTERNAL |
| } re_error; |
| |
| /* a decoded packet */ |
| struct data_packet { |
| unsigned short buf_len; /* should be set by caller */ |
| DevChanID type; /* valid when status is RS_GOOD_PKT */ |
| unsigned short len; /* --"-- */ |
| unsigned int crc; /* crc for the unescaped pkt */ |
| unsigned char *data; /* should be set by caller */ |
| }; |
| |
| /* |
| * Purpose: typedef for flow control function |
| * |
| * Params: |
| * Input: fc_char the flow control character in question |
| * In/Out: cb_data callback data as set in the fc_data |
| * field of re_config, typically device id |
| * |
| * This callback would tpyically respond to received XON and XOFF |
| * characters by controlling the transmit side of the device. |
| */ |
| typedef void (*fc_cb_func)(char fc_char, void *cb_data); |
| |
| |
| /* |
| * Purpose: typedef for the function to alloc the data buffer |
| * |
| * Params: |
| * In/Out: packet the data packet: len and type will be set on |
| * entry, and buf_len and data should |
| * be set by this routine if successful. |
| * cb_data callback data as set in the ba_data |
| * field of re_config, typically device id |
| * |
| * Returns: TRUE buffer allocated okay |
| * FALSE couldn't allocate buffer of required size |
| * for given type |
| * |
| * This callback should attempt to acquire a buffer for the data portion |
| * of the packet which is currently being received, based on the len and |
| * type fields supplied in packet. |
| * |
| * angel_DD_RxEng_BufferAlloc() is supplied for use as this callback, |
| * and will be sufficient for most devices. |
| */ |
| typedef bool (*BufferAlloc_CB_Fn)(struct data_packet *packet, void *cb_data); |
| |
| |
| /* |
| * The static info needed by the engine, may vary per device. |
| * |
| * fc_set and esc_set are bitmaps, e.g. bit 3 == charcode 3 == ASCII ETX. |
| * Thus any of the first 32 charcodes can be set for flow control or to |
| * be escaped. |
| * |
| * Note that esc_set should include all of fc_set, and should have bits |
| * set for stx, etx and esc, as a minimum. |
| * |
| * If character codes > 31 need to be used then fc_set and esc_set |
| * and their handling can be extended to use arrays and bit manipulation |
| * macros, potentially up to the full 256 possible chars. |
| * |
| * Note too that this could/should be shared with the tx engine. |
| */ |
| |
| struct re_config { |
| unsigned char stx; /* the STX char for this device */ |
| unsigned char etx; /* the ETX --"-- */ |
| unsigned char esc; /* the ESC --"-- */ |
| unsigned int fc_set; /* bitmap of flow control chars */ |
| unsigned int esc_set; /* bitmap of special chars */ |
| fc_cb_func fc_callback; /* flow control callback func */ |
| void *fc_data; /* data to pass to fc_callback */ |
| BufferAlloc_CB_Fn ba_callback; /* buffer alloc callback */ |
| void *ba_data; /* data to pass to ba_calback */ |
| }; |
| |
| /* the dynamic info needed by the rx engine */ |
| struct re_state { |
| unsigned char rx_state; /* 3 bits pkt state, 1 prepro state */ |
| unsigned short field_c; /* chars left in current field */ |
| unsigned short index; /* index into buffer */ |
| unsigned int crc; /* crc accumulator */ |
| re_error error; /* valid only if status is RS_BAD_PKT */ |
| const struct re_config *config; /* pointer to static config */ |
| }; |
| |
| /* dynamic state info needed by the tx engine */ |
| struct te_state { |
| unsigned short field_c; /* position in current field */ |
| unsigned char tx_state; /* encodes n,e, and f (2+1+2=5 bits) */ |
| unsigned char encoded; /* escape-encoded char for transmission */ |
| const struct re_config *config; /* pointer to static config */ |
| unsigned int crc; /* space for CRC (before escaping) */ |
| }; |
| |
| /* |
| * Function: Angel_RxEngineInit |
| * Purpose: Initialise state (during device init) for engine. |
| * |
| * Params: |
| * Input: config static config info |
| * In/Out: state internal state |
| */ |
| |
| void Angel_RxEngineInit(const struct re_config *config, |
| struct re_state *state); |
| |
| /* |
| * Function: Angel_RxEngine |
| * Purpose: Rx Engine for character-based devices |
| * |
| * Params: |
| * Input: new_ch the latest character |
| * |
| * In/Out: packet details of packet |
| * packet.buf_len and packet.data must |
| * be set on entry! |
| * state internal state, intially set by |
| * angel_RxEngineInit() |
| * |
| * Returns: re_status (see above) |
| * |
| */ |
| |
| re_status Angel_RxEngine(unsigned char new_ch, struct data_packet *packet, |
| struct re_state *state); |
| |
| /* |
| * This can be used as the buffer allocation callback for the rx engine, |
| * and will make use of angel_DD_GetBuffer() [in devdrv.h]. |
| * |
| * Saves duplicating this callback function in every device driver that |
| * uses the rx engine. |
| * |
| * Note that this REQUIRES that the device id is installed as ba_data |
| * in the rx engine config structure for the driver. |
| */ |
| bool angel_DD_RxEng_BufferAlloc( struct data_packet *packet, void *cb_data ); |
| |
| /* |
| * Function: Angel_TxEngineInit |
| * Purpose: Set up tx engine at start of new packet, calculate CRC etc. |
| * (This should perform the actions described under |
| * "Initialisation" above) |
| * |
| * Params: |
| * Input: config static config info |
| * packet the packet to transmit |
| * In/Out: state internal state |
| */ |
| |
| void Angel_TxEngineInit(const struct re_config *config, |
| const struct data_packet *packet, |
| struct te_state *state); |
| |
| /* |
| * Function: Angel_TxEngine |
| * Purpose: Tx Engine for character-based devices |
| * |
| * Params: |
| * Input: packet details of packet |
| * packet.len, packet.data and |
| * packet.type must |
| * be set on entry! |
| * In/Out: state internal state, intially set by |
| * angel_TxEngineStart() |
| * Output: tx_ch the character to be transmitted |
| * (NOT SET if return code is TS_IDLE) |
| * |
| * Returns: te_status (see above) |
| */ |
| |
| te_status Angel_TxEngine(const struct data_packet *packet, |
| struct te_state *state, |
| unsigned char *tx_ch); |
| |
| |
| |
| #endif /* !defined(angel_rxtx_h) */ |
| |
| /* EOF rxtx.h */ |
