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Diffstat (limited to 'firmware/microblaze/lib/dbsm.h')
| -rw-r--r-- | firmware/microblaze/lib/dbsm.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/firmware/microblaze/lib/dbsm.h b/firmware/microblaze/lib/dbsm.h new file mode 100644 index 000000000..cb7e12fc3 --- /dev/null +++ b/firmware/microblaze/lib/dbsm.h @@ -0,0 +1,90 @@ +/* -*- c++ -*- */ +/* + * Copyright 2007 Free Software Foundation, Inc. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef INCLUDED_DBSM_H +#define INCLUDED_DBSM_H + +/* + * Double Buffering State Machine + */ + +#include <stdint.h> +#include <stdbool.h> + +struct _dbsm; +typedef struct _dbsm dbsm_t; + +/* + * pointer to function that does packet inspection. + * + * If one of these returns true, it means that the s/w + * handled that packet, and that it should NOT be passed + * on to the normal destination port. + */ +typedef bool (*inspector_t)(dbsm_t *sm, int buf_this); + +bool dbsm_nop_inspector(dbsm_t *sm, int buf_this); // returns false + + +typedef struct +{ + uint16_t port; + uint16_t first_line; + uint16_t last_line; +} buf_cmd_args_t; + +/*! + * double buffer state machine + */ +struct _dbsm +{ + uint8_t buf0; // Must be even. This machine uses buf0 and buf0+1 + uint8_t running; + uint8_t rx_idle; + uint8_t tx_idle; + buf_cmd_args_t recv_args; + buf_cmd_args_t send_args; + inspector_t inspect; + uint32_t precomputed_receive_to_buf_ctrl_word[2]; + uint32_t precomputed_send_from_buf_ctrl_word[2]; + int last_line_adj; +}; + +void dbsm_init(dbsm_t *sm, int buf0, + const buf_cmd_args_t *recv, const buf_cmd_args_t *send, + inspector_t inspect); + +void dbsm_start(dbsm_t *sm); +void dbsm_stop(dbsm_t *sm); +void dbsm_process_status(dbsm_t *sm, uint32_t status); +void dbsm_handle_tx_underrun(dbsm_t *sm); +void dbsm_handle_rx_overrun(dbsm_t *sm); + +/* + * The cpu calls this when it want to ensure that it can send a buffer + * to the same destination being used by this state machine. + * + * If neither buffer is EMPTYING it returns immediately. If a buffer + * is EMPYTING, it waits for the h/w to transition to the DONE or + * ERROR state. + * + * When this function returns, the caller queues it's buffer and busy + * waits for it to complete. + */ +void dbsm_wait_for_opening(dbsm_t *sm); + +#endif /* INCLUDED_DBSM_H */ |