Go back to using DMA to get SCBs down to the adapter.

SCB paging is now handled almost entirely by the sequencer and also uses
DMA.  This should make SCB paging at least an order of magnitude more
efficient and vastly simplifies the implementation.

Add a few space optimizations so this code still fits on aic7770 chips.

Update comments.

1 files changed, 71 insertions, 54 deletions

diff --git a/sys/dev/aic7xxx/aic7xxx_reg.h b/sys/dev/aic7xxx/aic7xxx_reg.h
index c4c9ad4..c48a49a 100644
--- a/sys/dev/aic7xxx/aic7xxx_reg.h
+++ b/sys/dev/aic7xxx/aic7xxx_reg.h
@@ -28,7 +28,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: aic7xxx_reg.h,v 1.12 1996/06/09 17:29:12 gibbs Exp $
+ *	$Id: aic7xxx_reg.h,v 1.12.2.2 1996/10/06 01:24:13 gibbs Exp $
  */
 
 /*
@@ -408,6 +408,7 @@
 #define			NO_IDENT	0x21	/* no IDENTIFY after reconnect*/
 #define			NO_MATCH	0x31	/* no cmd match for reconnect */
 #define			EXTENDED_MSG	0x41	/* Extended message received */
+#define			DMA_UP_SCB	0x51
 #define			REJECT_MSG	0x61	/* Reject message received */
 #define			BAD_STATUS	0x71	/* Bad status from target */
 #define			RESIDUAL	0x81	/* Residual byte count != 0 */
@@ -529,6 +530,7 @@
 #define		MK_MESSAGE      0x80
 #define		DISCENB         0x40
 #define		TAG_ENB		0x20
+#define		ABORT_SCB	0x08
 #define		DISCONNECTED	0x04
 #define		SCB_TAG_TYPE	0x03
 #define	SCB_TCL			0x0a1
@@ -553,7 +555,7 @@
 #define		SCB_DATACNT0	0x0b0
 #define		SCB_DATACNT1	0x0b1
 #define		SCB_DATACNT2	0x0b2
-/* UNUSED - QUAD PADDING	0x0b3 */
+#define	SCB_LINKED_NEXT		0x0b3
 #define SCB_CMDPTR		0x0b4
 #define		SCB_CMDPTR0	0x0b4
 #define		SCB_CMDPTR1	0x0b5
@@ -563,6 +565,10 @@
 #define SCB_TAG			0x0b9
 #define	SCB_NEXT		0x0ba
 #define	SCB_PREV		0x0bb
+#define	SCB_ACTIVE0		0x0bc
+#define	SCB_ACTIVE1		0x0bd
+#define	SCB_ACTIVE2		0x0be
+#define	SCB_ACTIVE3		0x0bf
 
 #ifdef __linux__
 #define	SG_SIZEOF		0x0c		/* sizeof(struct scatterlist) */
@@ -644,11 +650,10 @@
 
 /*
  * The sequencer will stick the frist byte of any rejected message here so
- * we can see what is getting thrown away.  Extended messages put the
- * extended message type in REJBYTE_EXT.
+ * we can see what is getting thrown away.
  */
 #define REJBYTE			0x030
-#define REJBYTE_EXT		0x031
+#define	TARGID_MASK		0x031
 
 /*
  * Bit vector of targets that have disconnection disabled.
@@ -662,7 +667,7 @@
  */
 #define MSG_LEN			0x034
 
-/* We reserve 8bytes to store outgoing messages */
+/* We reserve 6bytes to store outgoing messages */
 #define MSG0			0x035
 #define		COMP_MSG0	0xcb      /* 2's complement of MSG0 */
 #define MSG1			0x036
@@ -670,92 +675,104 @@
 #define MSG3			0x038
 #define MSG4			0x039
 #define MSG5			0x03a
-#define MSG6			0x03b
-#define MSG7			0x03c
 
-/*
- * These are offsets into the card's scratch ram.  Some of the values are
- * specified in the AHA2742 technical reference manual and are initialized
- * by the BIOS at boot time.
- */
-#define LASTPHASE		0x03d
-#define ARG_1			0x03e
-#define RETURN_1		0x03f
+#define LASTPHASE		0x03b
+#define ARG_1			0x03c
+#define RETURN_1		0x03c
 #define		SEND_MSG	0x80
 #define		SEND_SENSE	0x40
 #define		SEND_REJ	0x20
 #define		SCB_PAGEDIN	0x10
 
-#define SIGSTATE		0x040
-
-#define DMAPARAMS		0x041	/* Parameters for DMA Logic */
+#define DMAPARAMS		0x03d	/* Parameters for DMA Logic */
 
-#define	SG_COUNT		0x042
-#define	SG_NEXT			0x043	/* working value of SG pointer */
-#define		SG_NEXT0	0x043
-#define		SG_NEXT1	0x044
-#define		SG_NEXT2	0x045
-#define		SG_NEXT3	0x046
-
-#define	SCBCOUNT		0x047	/*
+#define	SCBCOUNT		0x03e	/*
 					 * Number of SCBs supported by
 					 * this card.
 					 */
-#define	COMP_SCBCOUNT		0x048	/*
+#define	COMP_SCBCOUNT		0x03f	/*
 					 * Two's compliment of SCBCOUNT
 					 */
-#define QCNTMASK		0x049	/*
+#define QCNTMASK		0x040	/*
 					 * Mask of bits to test against
 					 * when looking at the Queue Count
 					 * registers.  Works around a bug
 					 * on aic7850 chips. 
 					 */
-#define FLAGS			0x04a
+#define FLAGS			0x041
 #define		SINGLE_BUS	0x00
 #define		TWIN_BUS	0x01
 #define		WIDE_BUS	0x02
 #define		PAGESCBS	0x04
+#define		SCB_LISTED	0x08
 #define		DPHASE		0x10
-#define		SELECTED	0x20
 #define		IDENTIFY_SEEN	0x40
 #define		RESELECTED	0x80
 
-#define	SAVED_TCL		0x04b	/*
+#define	SAVED_TCL		0x042	/*
 					 * Temporary storage for the
 					 * target/channel/lun of a
 					 * reconnecting target
 					 */
-#define	ACTIVE_A		0x04c
-#define	ACTIVE_B		0x04d
-#define WAITING_SCBH		0x04e	/*
+#define	SG_COUNT		0x043
+#define	SG_NEXT			0x044	/* working value of SG pointer */
+#define		SG_NEXT0	0x044
+#define		SG_NEXT1	0x045
+#define		SG_NEXT2	0x046
+#define		SG_NEXT3	0x047
+
+#define WAITING_SCBH		0x048	/*
 					 * head of list of SCBs awaiting
 					 * selection
 					 */
-#define DISCONNECTED_SCBH	0x04f	/*
+#define SAVED_LINKPTR		0x049
+#define SAVED_SCBPTR		0x04a
+#define ULTRA_ENB		0x04b
+#define ULTRA_ENB_B		0x04c
+
+#define MSGIN_EXT_LEN		0x04d
+#define MSGIN_EXT_OPCODE	0x04e
+#define MSGIN_EXT_BYTE0		0x04f
+#define MSGIN_EXT_BYTE1		0x050
+#define MSGIN_EXT_BYTE2		0x051	/*
+					 * This location, stores the last
+					 * byte of an extended message if
+					 * it passes the two bytes of space
+					 * we allow now.  This byte isn't
+					 * used for anything, it just makes
+					 * the code shorter for tossing
+					 * extra bytes.
+					 */
+#define	MSGIN_EXT_LASTBYTE	0x052	/* Used as the address for range
+					 * checking, not used for storage.
+					 */
+
+#define DISCONNECTED_SCBH	0x052	/*
 					 * head of list of SCBs that are
 					 * disconnected.  Used for SCB
 					 * paging.
 					 */
-#define		SCB_LIST_NULL	0xff
-
-#define SAVED_LINKPTR		0x050
-#define SAVED_SCBPTR		0x051
-#define ULTRA_ENB		0x052
-#define ULTRA_ENB_B		0x053
-
-#define MSGIN_EXT_LEN		0x054
-#define MSGIN_EXT_OPCODE	0x055
-#define MSGIN_EXT_BYTE0		0x056
-#define MSGIN_EXT_BYTE1		0x057
-#define	MSGIN_EXT_LASTBYTE	0x058	/*
-					 * We don't use this location, but
-					 * continue to store bytes until
-					 * we reach this address (avoids
-					 * a more complicated compare).
-					 * So, we can store at most 2
-					 * bytes for now.
+#define FREE_SCBH		0x053	/*
+					 * head of list of SCBs that are
+					 * not in use.  Used for SCB paging.
 					 */
 
+
+#define HSCB_ADDR0		0x054
+#define HSCB_ADDR1		0x055
+#define HSCB_ADDR2		0x056
+#define HSCB_ADDR3		0x057
+
+#define	CUR_SCBID		0x058
+#define QFULLCNT		0x059
+
+#define		SCB_LIST_NULL	0xff
+
+/*
+ * These are offsets into the card's scratch ram.  Some of the values are
+ * specified in the AHA2742 technical reference manual and are initialized
+ * by the BIOS at boot time.
+ */
 #define SCSICONF		0x05a
 #define		RESET_SCSI	0x40