- BT_CONTROL(BT_H2B_ATN); /* clears too fast to catch? */
- bt->state = BT_STATE_WRITE_CONSUME;
- return SI_SM_CALL_WITHOUT_DELAY; /* it MIGHT sail through */
-
- case BT_STATE_WRITE_CONSUME: /* BMCs usually blow right thru here */
- if (status & (BT_H2B_ATN | BT_B_BUSY)) break;
- bt->state = BT_STATE_B2H_WAIT;
- /* fall through with status */
-
- /* Stay in BT_STATE_B2H_WAIT until a packet matches. However, spinning
- hard here, constantly reading status, seems to hold off the
- generation of B2H_ATN so ALWAYS return CALL_WITH_DELAY. */
-
- case BT_STATE_B2H_WAIT:
- if (!(status & BT_B2H_ATN)) break;
-
- /* Assume ordered, uncached writes: no need to wait */
- if (!(status & BT_H_BUSY)) BT_CONTROL(BT_H_BUSY); /* set */
- BT_CONTROL(BT_B2H_ATN); /* clear it, ACK to the BMC */
- BT_CONTROL(BT_CLR_RD_PTR); /* reset the queue */
- i = read_all_bytes(bt);
- BT_CONTROL(BT_H_BUSY); /* clear */
- if (!i) break; /* Try this state again */
- bt->state = BT_STATE_READ_END;
- return SI_SM_CALL_WITHOUT_DELAY; /* for logging */
-
- case BT_STATE_READ_END:
-
- /* I could wait on BT_H_BUSY to go clear for a truly clean
- exit. However, this is already done in XACTION_START
- and the (possible) extra loop/status/possible wait affects
- performance. So, as long as it works, just ignore H_BUSY */
-
-#ifdef MAKE_THIS_TRUE_IF_NECESSARY
-
- if (status & BT_H_BUSY) break;
-#endif
- bt->seq++;
- bt->state = BT_STATE_IDLE;
- return SI_SM_TRANSACTION_COMPLETE;
+ BT_CONTROL(BT_H2B_ATN); /* can clear too fast to catch */
+ BT_STATE_CHANGE(BT_STATE_WRITE_CONSUME,
+ SI_SM_CALL_WITHOUT_DELAY);
+
+ case BT_STATE_WRITE_CONSUME:
+ if (status & (BT_B_BUSY | BT_H2B_ATN))
+ BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY);
+ BT_STATE_CHANGE(BT_STATE_READ_WAIT,
+ SI_SM_CALL_WITHOUT_DELAY);
+
+ /* Spinning hard can suppress B2H_ATN and force a timeout */
+
+ case BT_STATE_READ_WAIT:
+ if (!(status & BT_B2H_ATN))
+ BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY);
+ BT_CONTROL(BT_H_BUSY); /* set */
+
+ /* Uncached, ordered writes should just proceeed serially but
+ some BMCs don't clear B2H_ATN with one hit. Fast-path a
+ workaround without too much penalty to the general case. */
+
+ BT_CONTROL(BT_B2H_ATN); /* clear it to ACK the BMC */
+ BT_STATE_CHANGE(BT_STATE_CLEAR_B2H,
+ SI_SM_CALL_WITHOUT_DELAY);
+
+ case BT_STATE_CLEAR_B2H:
+ if (status & BT_B2H_ATN) { /* keep hitting it */
+ BT_CONTROL(BT_B2H_ATN);
+ BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY);
+ }
+ BT_STATE_CHANGE(BT_STATE_READ_BYTES,
+ SI_SM_CALL_WITHOUT_DELAY);
+
+ case BT_STATE_READ_BYTES:
+ if (!(status & BT_H_BUSY)) /* check in case of retry */
+ BT_CONTROL(BT_H_BUSY);
+ BT_CONTROL(BT_CLR_RD_PTR); /* start of BMC2HOST buffer */
+ i = read_all_bytes(bt); /* true == packet seq match */
+ BT_CONTROL(BT_H_BUSY); /* NOW clear */
+ if (!i) /* Not my message */
+ BT_STATE_CHANGE(BT_STATE_READ_WAIT,
+ SI_SM_CALL_WITHOUT_DELAY);
+ bt->state = bt->complete;
+ return bt->state == BT_STATE_IDLE ? /* where to next? */
+ SI_SM_TRANSACTION_COMPLETE : /* normal */
+ SI_SM_CALL_WITHOUT_DELAY; /* Startup magic */
+
+ case BT_STATE_LONG_BUSY: /* For example: after FW update */
+ if (!(status & BT_B_BUSY)) {
+ reset_flags(bt); /* next state is now IDLE */
+ bt_init_data(bt, bt->io);
+ }
+ return SI_SM_CALL_WITH_DELAY; /* No repeat printing */