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Diffstat (limited to 'gdb/rdi-share/rxtx.h')
| -rw-r--r-- | gdb/rdi-share/rxtx.h | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/gdb/rdi-share/rxtx.h b/gdb/rdi-share/rxtx.h new file mode 100644 index 00000000000..204e99870fa --- /dev/null +++ b/gdb/rdi-share/rxtx.h @@ -0,0 +1,263 @@ +/* + * 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 */ |