diff options
Diffstat (limited to 'usrp2/firmware/lib/bsm12.c')
| -rw-r--r-- | usrp2/firmware/lib/bsm12.c | 128 |
1 files changed, 119 insertions, 9 deletions
diff --git a/usrp2/firmware/lib/bsm12.c b/usrp2/firmware/lib/bsm12.c index 845046d65..c996e6496 100644 --- a/usrp2/firmware/lib/bsm12.c +++ b/usrp2/firmware/lib/bsm12.c @@ -16,6 +16,13 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +/* + * buffer state machine: 1 input to two outputs + * + * Typically used to read packets from the ethernet and then after inspecting, + * handle the packet in firmware or pass it on to 1 of the 2 buffer destinations. + */ + #ifdef HAVE_CONFIG_H #include <config.h> #endif @@ -35,8 +42,11 @@ typedef enum { } buffer_state_t; static buffer_state_t buffer_state[NBUFFERS]; -static unsigned char buffer_dst[NBUFFERS]; // 0 or 1 static uint32_t last_send_ctrl[NBUFFERS]; +static int8_t buffer_target[NBUFFERS]; // -1, 0 or 1. +static uint8_t buffer_dst[NBUFFERS]; // 0 or 1. Valid only when BF_EMPTYING + +#define ST_IDLE (-1) void bsm12_init(bsm12_t *sm, int buf0, @@ -54,9 +64,9 @@ bsm12_init(bsm12_t *sm, int buf0, sm->send_args[0] = *send0; sm->send_args[1] = *send1; - sm->rx_idle = true; - sm->tx_idle[0] = true; - sm->tx_idle[1] = true; + sm->rx_state = ST_IDLE; + sm->tx_state[0] = ST_IDLE; + sm->tx_state[1] = ST_IDLE; sm->inspect = inspect; @@ -72,6 +82,17 @@ bsm12_init(bsm12_t *sm, int buf0, buffer_state[sm->buf0 + 1] = BS_EMPTY; buffer_state[sm->buf0 + 2] = BS_EMPTY; + buffer_target[sm->buf0 + 0] = -1; + buffer_target[sm->buf0 + 1] = -1; + buffer_target[sm->buf0 + 2] = -1; + + for (int i = 0; i < NBUFFERS; i++) + sm->next_buf[i] = buf0; + + sm->next_buf[buf0 + 0] = buf0 + 1; + sm->next_buf[buf0 + 1] = buf0 + 2; + sm->next_buf[buf0 + 2] = buf0 + 0; + for (int i = 0; i < 3; i++){ sm->precomputed_receive_to_buf_ctrl_word[i] = (BPC_READ @@ -102,11 +123,15 @@ bsm12_receive_to_buf(bsm12_t *sm, int bufno) static inline void bsm12_send_from_buf(bsm12_t *sm, int bufno, int dst_idx) { - uint32_t t = (sm->precomputed_send_from_buf_ctrl_word[bufno & 0x3][dst_idx] - | BPC_LAST_LINE(buffer_pool_status->last_line[bufno] - sm->last_line_adj)); + dst_idx &= 0x1; + + uint32_t t = + (sm->precomputed_send_from_buf_ctrl_word[bufno & 0x3][dst_idx] + | BPC_LAST_LINE(buffer_pool_status->last_line[bufno] - sm->last_line_adj)); buffer_pool_ctrl->ctrl = t; last_send_ctrl[bufno] = t; + buffer_dst[bufno] = dst_idx; } static inline void @@ -124,13 +149,17 @@ bsm12_start(bsm12_t *sm) buffer_state[sm->buf0 + 1] = BS_EMPTY; buffer_state[sm->buf0 + 2] = BS_EMPTY; + buffer_target[sm->buf0 + 0] = -1; + buffer_target[sm->buf0 + 1] = -1; + buffer_target[sm->buf0 + 2] = -1; + bp_clear_buf(sm->buf0 + 0); bp_clear_buf(sm->buf0 + 1); bp_clear_buf(sm->buf0 + 2); - sm->rx_idle = false; - sm->tx_idle[0] = true; - sm->tx_idle[1] = true; + sm->rx_state = 0; + sm->tx_state[0] = ST_IDLE; + sm->tx_state[1] = ST_IDLE; bsm12_receive_to_buf(sm, sm->buf0); buffer_state[sm->buf0] = BS_FILLING; } @@ -182,6 +211,87 @@ bsm12_process_status(bsm12_t *sm, uint32_t status) static void bsm12_process_helper(bsm12_t *sm, int buf_this) { + bp_clear_buf(buf_this); + + if (buffer_state[buf_this] == BS_FILLING){ + + buffer_state[buf_this] = BS_FULL; + buffer_target[buf_this] = -1; + + // + // where does this packet go? + // + int dst = sm->inspect(sm, buf_this); + if (dst == -1){ + // + // f/w handled the packet; refill the buffer + // + bsm12_receive_to_buf(sm, buf_this); + buffer_state[buf_this] = BS_FILLING; + buffer_target[buf_this] = -1; + sm->rx_state = buf_this & 0x3; + } + else { // goes to dst 0 or 1 + // + // If the next buffer is empty, start a receive on it + // + int t = sm->next_buf[buf_this]; + if (buffer_state[t] == BS_EMPTY){ + bsm12_receive_to_buf(sm, t); + buffer_state[t] = BS_FILLING; + buffer_target[t] = -1; + sm->rx_state = t & 0x3; + } + else + sm->rx_state = ST_IDLE; + + // + // If the destination is idle, start the xfer, othewise remember it + // + if (sm->tx_state[dst] == ST_IDLE){ + bsm12_send_from_buf(sm, buf_this, dst); + sm->tx_state[dst] = buf_this & 0x3; + buffer_state[buf_this] = BS_EMPTYING; + buffer_target[buf_this] = -1; + } + else { + buffer_target[buf_this] = dst; + } + } + } + + else { // BS_EMPTYING + + buffer_state[buf_this] = BS_EMPTY; + buffer_target[buf_this] = -1; + + if (sm->rx_state == ST_IDLE){ // fire off another receive + sm->rx_state = buf_this & 0x3; + bsm12_receive_to_buf(sm, buf_this); + buffer_state[buf_this] = BS_FILLING; + buffer_target[buf_this] = -1; + } + + int dst = buffer_dst[buf_this]; // the dst we were emptying into + // is the next buffer full and for us? + int t = sm->next_buf[buf_this]; + if (buffer_target[t] == dst){ // yes, + bsm12_send_from_buf(sm, t, dst); // send it + buffer_state[t] = BS_EMPTYING; + buffer_target[t] = -1; + sm->tx_state[dst] = t & 0x3; + } + // how about the one after that? + else if (buffer_target[t=sm->next_buf[t]] == dst){ // yes, + bsm12_send_from_buf(sm, t, dst); // send it + buffer_state[t] = BS_EMPTYING; + buffer_target[t] = -1; + sm->tx_state[dst] = t & 0x3; + } + else { + sm->tx_state[dst] = ST_IDLE; + } + } } static void |