siop.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

	for (cbdp = TAILQ_FIRST(&sc->cmds); cbdp != NULL;
	    cbdp = TAILQ_NEXT(cbdp, next)) {
		if (dsa >= cbdp->xferdma->dm_segs[0].ds_addr &&
	    	    dsa < cbdp->xferdma->dm_segs[0].ds_addr + PAGE_SIZE) {
			dsa -= cbdp->xferdma->dm_segs[0].ds_addr;
			siop_cmd = &cbdp->cmds[dsa / sizeof(struct siop_xfer)];
			siop_table_sync(siop_cmd,
			    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
			break;
		}
	} 
	if (cbdp == NULL) {
		siop_cmd = NULL;
	}
	if (siop_cmd) {
		xs = siop_cmd->xs;
		siop_target = siop_cmd->siop_target;
		target = siop_cmd->xs->sc_link->target;
		lun = siop_cmd->xs->sc_link->lun;
		tag = siop_cmd->tag;
		siop_lun = siop_target->siop_lun[lun];
#ifdef DIAGNOSTIC
		if (siop_cmd->status != CMDST_ACTIVE &&
		    siop_cmd->status != CMDST_SENSE_ACTIVE) {
			printf("siop_cmd (lun %d) not active (%d)\n",
				lun, siop_cmd->status);
			xs = NULL;
			siop_target = NULL;
			target = -1;
			lun = -1;
			tag = -1;
			siop_lun = NULL;
			siop_cmd = NULL;
		} else if (siop_lun->siop_tag[tag].active != siop_cmd) {
			printf("siop_cmd (lun %d tag %d) not in siop_lun "
			    "active (%p != %p)\n", lun, tag, siop_cmd,
			    siop_lun->siop_tag[tag].active);
		}
#endif
	} else {
		xs = NULL;
		siop_target = NULL;
		target = -1;
		lun = -1;
		tag = -1;
		siop_lun = NULL;
	}
	if (istat & ISTAT_DIP) {
		dstat = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_DSTAT);
#ifdef DIAGNOSTIC
		printf("DSTAT: 0x%02x\n", dstat);
#endif
		if (dstat & DSTAT_SSI) {
			printf("single step dsp 0x%08x dsa 0x%08x\n",
			    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP),
			    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA));
			if ( bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) < 0xc0000000) {
				printf("* uncached inst 0x%08x 0x%08x\n",
					*(uint32_t*)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) + 0xa0000000),
					*(uint32_t*)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) + 0xa0000004));
				printf("* cached inst 0x%08x 0x%08x\n",
					*(uint32_t*)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) + 0x80000000),
					*(uint32_t*)(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) + 0x80000004));
			} else {
				printf("* inst 0x%08x 0x%08x\n",
					siop_script_read(sc,
					(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) - sc->sc_scriptaddr) / 4),
			    		siop_script_read(sc,
					(bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP) - sc->sc_scriptaddr) / 4 + 1));
			}
			if ((dstat & ~(DSTAT_DFE | DSTAT_SSI)) == 0 &&
			    (istat & ISTAT_SIP) == 0) {
				bus_space_write_1(sc->sc_rt, sc->sc_rh,
				    SIOP_DCNTL, bus_space_read_1(sc->sc_rt,
				    sc->sc_rh, SIOP_DCNTL) | DCNTL_STD);
			}
			return 1;
		}
		if (dstat & ~(DSTAT_SIR | DSTAT_DFE | DSTAT_SSI)) {
			printf("DMA IRQ:");
			if (dstat & DSTAT_IID)
				printf("Illegal instruction");
			if (dstat & DSTAT_ABRT)
				printf(" abort");
			if (dstat & DSTAT_BF)
				printf(" bus fault");
			if (dstat & DSTAT_MDPE)
				printf(" parity");
			if (dstat & DSTAT_DFE)
				printf(" dma fifo empty");
			printf(", DSP=0x%x DSA=0x%x: ",
			    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP),
			    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA));
			if (siop_cmd)
				printf("last msg_in=0x%x status=0x%x\n",
				    siop_cmd->siop_tables.msg_in[0],
				    letoh32(siop_cmd->siop_tables.status));
			else 
				printf("%s: current DSA invalid\n",
				    sc->sc_dev.dv_xname);
			need_reset = 1;
		}
	}
	if (istat & ISTAT_SIP) {
		if (istat & ISTAT_DIP)
			delay(10);
		/*
		 * Can't read sist0 & sist1 independantly, or we have to
		 * insert delay
		 */
		sist = bus_space_read_2(sc->sc_rt, sc->sc_rh, SIOP_SIST0);
		sstat1 = bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SSTAT1);
#ifdef SIOP_DEBUG_INTR
		printf("scsi interrupt, sist=0x%x sstat1=0x%x "
		    "DSA=0x%x DSP=0x%lx\n", sist,
		    bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SSTAT1),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP));
#endif
		if (sist & SIST0_RST) {
			siop_handle_reset(sc);
			siop_start(sc);
			/* no table to flush here */
			return 1;
		}
		if (sist & SIST0_SGE) {
			if (siop_cmd)
				sc_print_addr(xs->sc_link);
			else
				printf("%s:", sc->sc_dev.dv_xname);
			printf("scsi gross error\n");
			goto reset;
		}
		if ((sist & SIST0_MA) && need_reset == 0) {
			if (siop_cmd) { 
				int scratcha0;
				dstat = bus_space_read_1(sc->sc_rt, sc->sc_rh,
				    SIOP_DSTAT);
				/*
				 * first restore DSA, in case we were in a S/G
				 * operation.
				 */
				bus_space_write_4(sc->sc_rt, sc->sc_rh,
				    SIOP_DSA, siop_cmd->dsa);
				scratcha0 = bus_space_read_1(sc->sc_rt,
				    sc->sc_rh, SIOP_SCRATCHA);
				switch (sstat1 & SSTAT1_PHASE_MASK) {
				case SSTAT1_PHASE_STATUS:
				/*
				 * Previous phase may have aborted for any reason
				 * (for example, the target has less data to
				 * transfer than requested). Just go to status
				 * and the command should terminate.
				 */
					INCSTAT(siop_stat_intr_shortxfer);
					if ((dstat & DSTAT_DFE) == 0)
						siop_clearfifo(sc);
					/* no table to flush here */
					CALL_SCRIPT(Ent_status);
					return 1;
				case SSTAT1_PHASE_MSGIN:
					/*
					 * Target may be ready to disconnect.
					 * Save data pointers just in case.
					 */
					INCSTAT(siop_stat_intr_xferdisc);
					if (scratcha0 & A_flag_data)
						siop_sdp(siop_cmd);
					else if ((dstat & DSTAT_DFE) == 0)
						siop_clearfifo(sc);
					bus_space_write_1(sc->sc_rt, sc->sc_rh,
					    SIOP_SCRATCHA,
					    scratcha0 & ~A_flag_data);
					siop_table_sync(siop_cmd,
					    BUS_DMASYNC_PREREAD |
					    BUS_DMASYNC_PREWRITE);
					CALL_SCRIPT(Ent_msgin);
					return 1;
				}
				printf("%s: unexpected phase mismatch %d\n",
				    sc->sc_dev.dv_xname,
				    sstat1 & SSTAT1_PHASE_MASK);
			} else {
				printf("%s: phase mismatch without command\n",
				    sc->sc_dev.dv_xname);
			}
			need_reset = 1;
		}
		if (sist & SIST0_PAR) {
			/* parity error, reset */
			if (siop_cmd)
				sc_print_addr(xs->sc_link);
			else
				printf("%s:", sc->sc_dev.dv_xname);
			printf("parity error\n");
			goto reset;
		}
		if ((sist & (SIST1_STO << 8)) && need_reset == 0) {
			/* selection time out, assume there's no device here */
			if (siop_cmd) {
				siop_cmd->status = CMDST_DONE;
				xs->error = XS_SELTIMEOUT;
				freetarget = 1;
				goto end;
			} else {
				printf("%s: selection timeout without "
				    "command\n", sc->sc_dev.dv_xname);
				need_reset = 1;
			}
		}
		if (sist & SIST0_UDC) {
			/*
			 * unexpected disconnect. Usually the target signals
			 * a fatal condition this way. Attempt to get sense.
			 */
			 if (siop_cmd) {
				siop_cmd->siop_tables.status =
				    htole32(SCSI_CHECK);
				goto end;
			}
			printf("%s: unexpected disconnect without "
			    "command\n", sc->sc_dev.dv_xname);
			goto reset;
		}
		if (sist & (SIST1_SBMC << 8)) {
			/* SCSI bus mode change */
			if (siop_modechange(sc) == 0 || need_reset == 1)
				goto reset;
			if ((istat & ISTAT_DIP) && (dstat & DSTAT_SIR)) {
				/*
				 * We have a script interrupt. It will
				 * restart the script.
				 */
				goto scintr;
			}
			/*
			 * Else we have to restart the script ourself, at the
			 * interrupted instruction.
			 */
			bus_space_write_4(sc->sc_rt, sc->sc_rh, SIOP_DSP,
			    bus_space_read_4(sc->sc_rt, sc->sc_rh,
			    SIOP_DSP) - 8);
			return 1;
		}
		/* Else it's an unhandled exception (for now). */
		printf("%s: unhandled scsi interrupt, sist=0x%x sstat1=0x%x "
		    "DSA=0x%x DSP=0x%x\n", sc->sc_dev.dv_xname, sist,
		    bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SSTAT1),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSA),
		    bus_space_read_4(sc->sc_rt, sc->sc_rh, SIOP_DSP));
		if (siop_cmd) {
			siop_cmd->status = CMDST_DONE;
			xs->error = XS_SELTIMEOUT;
			goto end;
		}
		need_reset = 1;
	}
	if (need_reset) {
reset:
		/* fatal error, reset the bus */
		siop_resetbus(sc);
		/* no table to flush here */
		return 1;
	}

scintr:
	if ((istat & ISTAT_DIP) && (dstat & DSTAT_SIR)) { /* script interrupt */
		irqcode = bus_space_read_4(sc->sc_rt, sc->sc_rh,
		    SIOP_DSPS);
#ifdef SIOP_DEBUG_INTR
		printf("script interrupt 0x%x\n", irqcode);
#endif
		/*
		 * no command, or an inactive command is only valid for a
		 * reselect interrupt
		 */
		if ((irqcode & 0x80) == 0) {
			if (siop_cmd == NULL) {
				printf("%s: script interrupt (0x%x) with "
				    "invalid DSA !!!\n", sc->sc_dev.dv_xname,
				    irqcode);
				goto reset;
			}
			if (siop_cmd->status != CMDST_ACTIVE &&
			    siop_cmd->status != CMDST_SENSE_ACTIVE) {
				printf("%s: command with invalid status "
				    "(IRQ code 0x%x current status %d) !\n",
				    sc->sc_dev.dv_xname,
				    irqcode, siop_cmd->status);
				xs = NULL;
			}
		}
		switch(irqcode) {
		case A_int_err:
			printf("error, DSP=0x%x\n",
			    (int)(bus_space_read_4(sc->sc_rt, sc->sc_rh,
			    SIOP_DSP) - sc->sc_scriptaddr));
			if (xs) {
				xs->error = XS_SELTIMEOUT;
				goto end;
			} else {
				goto reset;
			}
		case A_int_reseltarg:
			printf("%s: reselect with invalid target\n",
				    sc->sc_dev.dv_xname);
			goto reset;
		case A_int_resellun: 
			INCSTAT(siop_stat_intr_lunresel);
			target = bus_space_read_1(sc->sc_rt, sc->sc_rh,
			    SIOP_SCRATCHA) & 0xf;
			lun = bus_space_read_1(sc->sc_rt, sc->sc_rh,
			    SIOP_SCRATCHA + 1);
			tag = bus_space_read_1(sc->sc_rt, sc->sc_rh,
			    SIOP_SCRATCHA + 2);
			siop_target = sc->targets[target];
			if (siop_target == NULL) {
				printf("%s: reselect with invalid "
				    "target %d\n", sc->sc_dev.dv_xname, target);
				goto reset;
			}
			siop_lun = siop_target->siop_lun[lun];
			if (siop_lun == NULL) {
				printf("%s: target %d reselect with invalid "
				    "lun %d\n", sc->sc_dev.dv_xname,
				    target, lun);
				goto reset;
			}
			if (siop_lun->siop_tag[tag].active == NULL) {
				printf("%s: target %d lun %d tag %d reselect "
				    "without command\n", sc->sc_dev.dv_xname,
				    target, lun, tag);
				goto reset;
			}
			siop_cmd = siop_lun->siop_tag[tag].active;
			bus_space_write_4(sc->sc_rt, sc->sc_rh, SIOP_DSP,
			    siop_cmd->dsa + sizeof(struct siop_xfer_common) +
			    Ent_ldsa_reload_dsa);
			siop_table_sync(siop_cmd, BUS_DMASYNC_PREWRITE);
			return 1;
		case A_int_reseltag:
			printf("%s: reselect with invalid tag\n",
				    sc->sc_dev.dv_xname);
			goto reset;
		case A_int_msgin:
		{
			int msgin = bus_space_read_1(sc->sc_rt, sc->sc_rh,
			    SIOP_SFBR);
			if (msgin == MSG_MESSAGE_REJECT) {
				int msg, extmsg;
				if (siop_cmd->siop_tables.msg_out[0] & 0x80) {
					/*
					 * Message was part of an identify +
					 * something else. Identify shouldn't
					 * have been rejected.
					 */
					msg = siop_cmd->siop_tables.msg_out[1];
					extmsg =
					    siop_cmd->siop_tables.msg_out[3];
				} else {
					msg = siop_cmd->siop_tables.msg_out[0];
					extmsg =
					    siop_cmd->siop_tables.msg_out[2];
				}
				if (msg == MSG_MESSAGE_REJECT) {
					/* MSG_REJECT for a MSG_REJECT! */
					if (xs)
						sc_print_addr(xs->sc_link);
					else
						printf("%s: ",
						   sc->sc_dev.dv_xname);
					printf("our reject message was "
					    "rejected\n");
					goto reset;
				}
				if (msg == MSG_EXTENDED &&
				    extmsg == MSG_EXT_WDTR) {
					if ((siop_target->flags & TARF_SYNC)
					    == 0) {
						siop_target->status = TARST_OK;
						siop_print_info(sc, target);
						/* no table to flush here */
						CALL_SCRIPT(Ent_msgin_ack);
						return 1;
					}
					siop_target->status = TARST_SYNC_NEG;
					siop_sdtr_msg(siop_cmd, 0,
					    sc->min_st_sync, sc->maxoff);
					siop_table_sync(siop_cmd,
					    BUS_DMASYNC_PREREAD |
					    BUS_DMASYNC_PREWRITE);
					CALL_SCRIPT(Ent_send_msgout);
					return 1;
				} else if (msg == MSG_EXTENDED &&
				    extmsg == MSG_EXT_SDTR) {
					siop_target->status = TARST_OK;
					siop_print_info(sc, target);
					/* no table to flush here */
					CALL_SCRIPT(Ent_msgin_ack);
					return 1;
				} else if (msg == MSG_SIMPLE_Q_TAG || 
				    msg == MSG_HEAD_OF_Q_TAG ||
				    msg == MSG_ORDERED_Q_TAG) {
					if (siop_handle_qtag_reject(
					    siop_cmd) == -1)
						goto reset;
					CALL_SCRIPT(Ent_msgin_ack);
					return 1;
				}
				if (xs)
					sc_print_addr(xs->sc_link);
				else
					printf("%s: ", sc->sc_dev.dv_xname);
				if (msg == MSG_EXTENDED) {
					printf("scsi message reject, extended "
					    "message sent was 0x%x\n", extmsg);
				} else {
					printf("scsi message reject, message "
					    "sent was 0x%x\n", msg);
				}
				/* no table to flush here */
				CALL_SCRIPT(Ent_msgin_ack);
				return 1;
			}
			if (xs)
				sc_print_addr(xs->sc_link);
			else
				printf("%s: ", sc->sc_dev.dv_xname);
			printf("unhandled message 0x%x\n",