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Diffstat (limited to 'drivers/scsi/53c7xx.scr')
-rw-r--r--drivers/scsi/53c7xx.scr1591
1 files changed, 0 insertions, 1591 deletions
diff --git a/drivers/scsi/53c7xx.scr b/drivers/scsi/53c7xx.scr
deleted file mode 100644
index 9c5694a2da8..00000000000
--- a/drivers/scsi/53c7xx.scr
+++ /dev/null
@@ -1,1591 +0,0 @@
-#undef DEBUG
-#undef EVENTS
-#undef NO_SELECTION_TIMEOUT
-#define BIG_ENDIAN
-
-; 53c710 driver. Modified from Drew Eckhardts driver
-; for 53c810 by Richard Hirst [richard@sleepie.demon.co.uk]
-;
-; I have left the script for the 53c8xx family in here, as it is likely
-; to be useful to see what I changed when bug hunting.
-
-; NCR 53c810 driver, main script
-; Sponsored by
-; iX Multiuser Multitasking Magazine
-; hm@ix.de
-;
-; Copyright 1993, 1994, 1995 Drew Eckhardt
-; Visionary Computing
-; (Unix and Linux consulting and custom programming)
-; drew@PoohSticks.ORG
-; +1 (303) 786-7975
-;
-; TolerANT and SCSI SCRIPTS are registered trademarks of NCR Corporation.
-;
-; PRE-ALPHA
-;
-; For more information, please consult
-;
-; NCR 53C810
-; PCI-SCSI I/O Processor
-; Data Manual
-;
-; NCR 53C710
-; SCSI I/O Processor
-; Programmers Guide
-;
-; NCR Microelectronics
-; 1635 Aeroplaza Drive
-; Colorado Springs, CO 80916
-; 1+ (719) 578-3400
-;
-; Toll free literature number
-; +1 (800) 334-5454
-;
-; IMPORTANT : This code is self modifying due to the limitations of
-; the NCR53c7,8xx series chips. Persons debugging this code with
-; the remote debugger should take this into account, and NOT set
-; breakpoints in modified instructions.
-;
-; Design:
-; The NCR53c7,8xx family of SCSI chips are busmasters with an onboard
-; microcontroller using a simple instruction set.
-;
-; So, to minimize the effects of interrupt latency, and to maximize
-; throughput, this driver offloads the practical maximum amount
-; of processing to the SCSI chip while still maintaining a common
-; structure.
-;
-; Where tradeoffs were needed between efficiency on the older
-; chips and the newer NCR53c800 series, the NCR53c800 series
-; was chosen.
-;
-; While the NCR53c700 and NCR53c700-66 lacked the facilities to fully
-; automate SCSI transfers without host processor intervention, this
-; isn't the case with the NCR53c710 and newer chips which allow
-;
-; - reads and writes to the internal registers from within the SCSI
-; scripts, allowing the SCSI SCRIPTS(tm) code to save processor
-; state so that multiple threads of execution are possible, and also
-; provide an ALU for loop control, etc.
-;
-; - table indirect addressing for some instructions. This allows
-; pointers to be located relative to the DSA ((Data Structure
-; Address) register.
-;
-; These features make it possible to implement a mailbox style interface,
-; where the same piece of code is run to handle I/O for multiple threads
-; at once minimizing our need to relocate code. Since the NCR53c700/
-; NCR53c800 series have a unique combination of features, making a
-; a standard ingoing/outgoing mailbox system, costly, I've modified it.
-;
-; - Mailboxes are a mixture of code and data. This lets us greatly
-; simplify the NCR53c810 code and do things that would otherwise
-; not be possible.
-;
-; The saved data pointer is now implemented as follows :
-;
-; Control flow has been architected such that if control reaches
-; munge_save_data_pointer, on a restore pointers message or
-; reconnection, a jump to the address formerly in the TEMP register
-; will allow the SCSI command to resume execution.
-;
-
-;
-; Note : the DSA structures must be aligned on 32 bit boundaries,
-; since the source and destination of MOVE MEMORY instructions
-; must share the same alignment and this is the alignment of the
-; NCR registers.
-;
-
-; For some systems (MVME166, for example) dmode is always the same, so don't
-; waste time writing it
-
-#if 1
-#define DMODE_MEMORY_TO_NCR
-#define DMODE_MEMORY_TO_MEMORY
-#define DMODE_NCR_TO_MEMORY
-#else
-#define DMODE_MEMORY_TO_NCR MOVE dmode_memory_to_ncr TO DMODE
-#define DMODE_MEMORY_TO_MEMORY MOVE dmode_memory_to_memory TO DMODE
-#define DMODE_NCR_TO_MEMORY MOVE dmode_ncr_to_memory TO DMODE
-#endif
-
-ABSOLUTE dsa_temp_lun = 0 ; Patch to lun for current dsa
-ABSOLUTE dsa_temp_next = 0 ; Patch to dsa next for current dsa
-ABSOLUTE dsa_temp_addr_next = 0 ; Patch to address of dsa next address
- ; for current dsa
-ABSOLUTE dsa_temp_sync = 0 ; Patch to address of per-target
- ; sync routine
-ABSOLUTE dsa_sscf_710 = 0 ; Patch to address of per-target
- ; sscf value (53c710)
-ABSOLUTE dsa_temp_target = 0 ; Patch to id for current dsa
-ABSOLUTE dsa_temp_addr_saved_pointer = 0; Patch to address of per-command
- ; saved data pointer
-ABSOLUTE dsa_temp_addr_residual = 0 ; Patch to address of per-command
- ; current residual code
-ABSOLUTE dsa_temp_addr_saved_residual = 0; Patch to address of per-command
- ; saved residual code
-ABSOLUTE dsa_temp_addr_new_value = 0 ; Address of value for JUMP operand
-ABSOLUTE dsa_temp_addr_array_value = 0 ; Address to copy to
-ABSOLUTE dsa_temp_addr_dsa_value = 0 ; Address of this DSA value
-
-;
-; Once a device has initiated reselection, we need to compare it
-; against the singly linked list of commands which have disconnected
-; and are pending reselection. These commands are maintained in
-; an unordered singly linked list of DSA structures, through the
-; DSA pointers at their 'centers' headed by the reconnect_dsa_head
-; pointer.
-;
-; To avoid complications in removing commands from the list,
-; I minimize the amount of expensive (at eight operations per
-; addition @ 500-600ns each) pointer operations which must
-; be done in the NCR driver by precomputing them on the
-; host processor during dsa structure generation.
-;
-; The fixed-up per DSA code knows how to recognize the nexus
-; associated with the corresponding SCSI command, and modifies
-; the source and destination pointers for the MOVE MEMORY
-; instruction which is executed when reselected_ok is called
-; to remove the command from the list. Similarly, DSA is
-; loaded with the address of the next DSA structure and
-; reselected_check_next is called if a failure occurs.
-;
-; Perhaps more concisely, the net effect of the mess is
-;
-; for (dsa = reconnect_dsa_head, dest = &reconnect_dsa_head,
-; src = NULL; dsa; dest = &dsa->next, dsa = dsa->next) {
-; src = &dsa->next;
-; if (target_id == dsa->id && target_lun == dsa->lun) {
-; *dest = *src;
-; break;
-; }
-; }
-;
-; if (!dsa)
-; error (int_err_unexpected_reselect);
-; else
-; longjmp (dsa->jump_resume, 0);
-;
-;
-
-#if (CHIP != 700) && (CHIP != 70066)
-; Define DSA structure used for mailboxes
-ENTRY dsa_code_template
-dsa_code_template:
-ENTRY dsa_code_begin
-dsa_code_begin:
-; RGH: Don't care about TEMP and DSA here
- DMODE_MEMORY_TO_NCR
- MOVE MEMORY 4, dsa_temp_addr_dsa_value, addr_scratch
- DMODE_MEMORY_TO_MEMORY
-#if (CHIP == 710)
- MOVE MEMORY 4, addr_scratch, saved_dsa
- ; We are about to go and select the device, so must set SSCF bits
- MOVE MEMORY 4, dsa_sscf_710, addr_scratch
-#ifdef BIG_ENDIAN
- MOVE SCRATCH3 TO SFBR
-#else
- MOVE SCRATCH0 TO SFBR
-#endif
- MOVE SFBR TO SBCL
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#else
- CALL scratch_to_dsa
-#endif
- CALL select
-; Handle the phase mismatch which may have resulted from the
-; MOVE FROM dsa_msgout if we returned here. The CLEAR ATN
-; may or may not be necessary, and we should update script_asm.pl
-; to handle multiple pieces.
- CLEAR ATN
- CLEAR ACK
-
-; Replace second operand with address of JUMP instruction dest operand
-; in schedule table for this DSA. Becomes dsa_jump_dest in 53c7,8xx.c.
-ENTRY dsa_code_fix_jump
-dsa_code_fix_jump:
- MOVE MEMORY 4, NOP_insn, 0
- JUMP select_done
-
-; wrong_dsa loads the DSA register with the value of the dsa_next
-; field.
-;
-wrong_dsa:
-#if (CHIP == 710)
-; NOTE DSA is corrupt when we arrive here!
-#endif
-; Patch the MOVE MEMORY INSTRUCTION such that
-; the destination address is the address of the OLD
-; next pointer.
-;
- MOVE MEMORY 4, dsa_temp_addr_next, reselected_ok_patch + 8
- DMODE_MEMORY_TO_NCR
-;
-; Move the _contents_ of the next pointer into the DSA register as
-; the next I_T_L or I_T_L_Q tupple to check against the established
-; nexus.
-;
- MOVE MEMORY 4, dsa_temp_next, addr_scratch
- DMODE_MEMORY_TO_MEMORY
-#if (CHIP == 710)
- MOVE MEMORY 4, addr_scratch, saved_dsa
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#else
- CALL scratch_to_dsa
-#endif
- JUMP reselected_check_next
-
-ABSOLUTE dsa_save_data_pointer = 0
-ENTRY dsa_code_save_data_pointer
-dsa_code_save_data_pointer:
-#if (CHIP == 710)
- ; When we get here, TEMP has been saved in jump_temp+4, DSA is corrupt
- ; We MUST return with DSA correct
- MOVE MEMORY 4, jump_temp+4, dsa_temp_addr_saved_pointer
-; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
- MOVE MEMORY 24, dsa_temp_addr_residual, dsa_temp_addr_saved_residual
- CLEAR ACK
-#ifdef DEBUG
- INT int_debug_saved
-#endif
- MOVE MEMORY 4, saved_dsa, addr_dsa
- JUMP jump_temp
-#else
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_temp, dsa_temp_addr_saved_pointer
- DMODE_MEMORY_TO_MEMORY
-; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
- MOVE MEMORY 24, dsa_temp_addr_residual, dsa_temp_addr_saved_residual
- CLEAR ACK
-#ifdef DEBUG
- INT int_debug_saved
-#endif
- RETURN
-#endif
-ABSOLUTE dsa_restore_pointers = 0
-ENTRY dsa_code_restore_pointers
-dsa_code_restore_pointers:
-#if (CHIP == 710)
- ; TEMP and DSA are corrupt when we get here, but who cares!
- MOVE MEMORY 4, dsa_temp_addr_saved_pointer, jump_temp + 4
-; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
- MOVE MEMORY 24, dsa_temp_addr_saved_residual, dsa_temp_addr_residual
- CLEAR ACK
- ; Restore DSA, note we don't care about TEMP
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#ifdef DEBUG
- INT int_debug_restored
-#endif
- JUMP jump_temp
-#else
- DMODE_MEMORY_TO_NCR
- MOVE MEMORY 4, dsa_temp_addr_saved_pointer, addr_temp
- DMODE_MEMORY_TO_MEMORY
-; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
- MOVE MEMORY 24, dsa_temp_addr_saved_residual, dsa_temp_addr_residual
- CLEAR ACK
-#ifdef DEBUG
- INT int_debug_restored
-#endif
- RETURN
-#endif
-
-ABSOLUTE dsa_check_reselect = 0
-; dsa_check_reselect determines whether or not the current target and
-; lun match the current DSA
-ENTRY dsa_code_check_reselect
-dsa_code_check_reselect:
-#if (CHIP == 710)
- /* Arrives here with DSA correct */
- /* Assumes we are always ID 7 */
- MOVE LCRC TO SFBR ; LCRC has our ID and his ID bits set
- JUMP REL (wrong_dsa), IF NOT dsa_temp_target, AND MASK 0x80
-#else
- MOVE SSID TO SFBR ; SSID contains 3 bit target ID
-; FIXME : we need to accommodate bit fielded and binary here for '7xx/'8xx chips
- JUMP REL (wrong_dsa), IF NOT dsa_temp_target, AND MASK 0xf8
-#endif
-;
-; Hack - move to scratch first, since SFBR is not writeable
-; via the CPU and hence a MOVE MEMORY instruction.
-;
- DMODE_MEMORY_TO_NCR
- MOVE MEMORY 1, reselected_identify, addr_scratch
- DMODE_MEMORY_TO_MEMORY
-#ifdef BIG_ENDIAN
- ; BIG ENDIAN ON MVME16x
- MOVE SCRATCH3 TO SFBR
-#else
- MOVE SCRATCH0 TO SFBR
-#endif
-; FIXME : we need to accommodate bit fielded and binary here for '7xx/'8xx chips
-; Are you sure about that? richard@sleepie.demon.co.uk
- JUMP REL (wrong_dsa), IF NOT dsa_temp_lun, AND MASK 0xf8
-; Patch the MOVE MEMORY INSTRUCTION such that
-; the source address is the address of this dsa's
-; next pointer.
- MOVE MEMORY 4, dsa_temp_addr_next, reselected_ok_patch + 4
- CALL reselected_ok
-#if (CHIP == 710)
-; Restore DSA following memory moves in reselected_ok
-; dsa_temp_sync doesn't really care about DSA, but it has an
-; optional debug INT so a valid DSA is a good idea.
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
- CALL dsa_temp_sync
-; Release ACK on the IDENTIFY message _after_ we've set the synchronous
-; transfer parameters!
- CLEAR ACK
-; Implicitly restore pointers on reselection, so a RETURN
-; will transfer control back to the right spot.
- CALL REL (dsa_code_restore_pointers)
- RETURN
-ENTRY dsa_zero
-dsa_zero:
-ENTRY dsa_code_template_end
-dsa_code_template_end:
-
-; Perform sanity check for dsa_fields_start == dsa_code_template_end -
-; dsa_zero, puke.
-
-ABSOLUTE dsa_fields_start = 0 ; Sanity marker
- ; pad 48 bytes (fix this RSN)
-ABSOLUTE dsa_next = 48 ; len 4 Next DSA
- ; del 4 Previous DSA address
-ABSOLUTE dsa_cmnd = 56 ; len 4 Scsi_Cmnd * for this thread.
-ABSOLUTE dsa_select = 60 ; len 4 Device ID, Period, Offset for
- ; table indirect select
-ABSOLUTE dsa_msgout = 64 ; len 8 table indirect move parameter for
- ; select message
-ABSOLUTE dsa_cmdout = 72 ; len 8 table indirect move parameter for
- ; command
-ABSOLUTE dsa_dataout = 80 ; len 4 code pointer for dataout
-ABSOLUTE dsa_datain = 84 ; len 4 code pointer for datain
-ABSOLUTE dsa_msgin = 88 ; len 8 table indirect move for msgin
-ABSOLUTE dsa_status = 96 ; len 8 table indirect move for status byte
-ABSOLUTE dsa_msgout_other = 104 ; len 8 table indirect for normal message out
- ; (Synchronous transfer negotiation, etc).
-ABSOLUTE dsa_end = 112
-
-ABSOLUTE schedule = 0 ; Array of JUMP dsa_begin or JUMP (next),
- ; terminated by a call to JUMP wait_reselect
-
-; Linked lists of DSA structures
-ABSOLUTE reconnect_dsa_head = 0 ; Link list of DSAs which can reconnect
-ABSOLUTE addr_reconnect_dsa_head = 0 ; Address of variable containing
- ; address of reconnect_dsa_head
-
-; These select the source and destination of a MOVE MEMORY instruction
-ABSOLUTE dmode_memory_to_memory = 0x0
-ABSOLUTE dmode_memory_to_ncr = 0x0
-ABSOLUTE dmode_ncr_to_memory = 0x0
-
-ABSOLUTE addr_scratch = 0x0
-ABSOLUTE addr_temp = 0x0
-#if (CHIP == 710)
-ABSOLUTE saved_dsa = 0x0
-ABSOLUTE emulfly = 0x0
-ABSOLUTE addr_dsa = 0x0
-#endif
-#endif /* CHIP != 700 && CHIP != 70066 */
-
-; Interrupts -
-; MSB indicates type
-; 0 handle error condition
-; 1 handle message
-; 2 handle normal condition
-; 3 debugging interrupt
-; 4 testing interrupt
-; Next byte indicates specific error
-
-; XXX not yet implemented, I'm not sure if I want to -
-; Next byte indicates the routine the error occurred in
-; The LSB indicates the specific place the error occurred
-
-ABSOLUTE int_err_unexpected_phase = 0x00000000 ; Unexpected phase encountered
-ABSOLUTE int_err_selected = 0x00010000 ; SELECTED (nee RESELECTED)
-ABSOLUTE int_err_unexpected_reselect = 0x00020000
-ABSOLUTE int_err_check_condition = 0x00030000
-ABSOLUTE int_err_no_phase = 0x00040000
-ABSOLUTE int_msg_wdtr = 0x01000000 ; WDTR message received
-ABSOLUTE int_msg_sdtr = 0x01010000 ; SDTR received
-ABSOLUTE int_msg_1 = 0x01020000 ; single byte special message
- ; received
-
-ABSOLUTE int_norm_select_complete = 0x02000000 ; Select complete, reprogram
- ; registers.
-ABSOLUTE int_norm_reselect_complete = 0x02010000 ; Nexus established
-ABSOLUTE int_norm_command_complete = 0x02020000 ; Command complete
-ABSOLUTE int_norm_disconnected = 0x02030000 ; Disconnected
-ABSOLUTE int_norm_aborted =0x02040000 ; Aborted *dsa
-ABSOLUTE int_norm_reset = 0x02050000 ; Generated BUS reset.
-ABSOLUTE int_norm_emulateintfly = 0x02060000 ; 53C710 Emulated intfly
-ABSOLUTE int_debug_break = 0x03000000 ; Break point
-#ifdef DEBUG
-ABSOLUTE int_debug_scheduled = 0x03010000 ; new I/O scheduled
-ABSOLUTE int_debug_idle = 0x03020000 ; scheduler is idle
-ABSOLUTE int_debug_dsa_loaded = 0x03030000 ; dsa reloaded
-ABSOLUTE int_debug_reselected = 0x03040000 ; NCR reselected
-ABSOLUTE int_debug_head = 0x03050000 ; issue head overwritten
-ABSOLUTE int_debug_disconnected = 0x03060000 ; disconnected
-ABSOLUTE int_debug_disconnect_msg = 0x03070000 ; got message to disconnect
-ABSOLUTE int_debug_dsa_schedule = 0x03080000 ; in dsa_schedule
-ABSOLUTE int_debug_reselect_check = 0x03090000 ; Check for reselection of DSA
-ABSOLUTE int_debug_reselected_ok = 0x030a0000 ; Reselection accepted
-#endif
-ABSOLUTE int_debug_panic = 0x030b0000 ; Panic driver
-#ifdef DEBUG
-ABSOLUTE int_debug_saved = 0x030c0000 ; save/restore pointers
-ABSOLUTE int_debug_restored = 0x030d0000
-ABSOLUTE int_debug_sync = 0x030e0000 ; Sanity check synchronous
- ; parameters.
-ABSOLUTE int_debug_datain = 0x030f0000 ; going into data in phase
- ; now.
-ABSOLUTE int_debug_check_dsa = 0x03100000 ; Sanity check DSA against
- ; SDID.
-#endif
-
-ABSOLUTE int_test_1 = 0x04000000 ; Test 1 complete
-ABSOLUTE int_test_2 = 0x04010000 ; Test 2 complete
-ABSOLUTE int_test_3 = 0x04020000 ; Test 3 complete
-
-
-; These should start with 0x05000000, with low bits incrementing for
-; each one.
-
-#ifdef EVENTS
-ABSOLUTE int_EVENT_SELECT = 0
-ABSOLUTE int_EVENT_DISCONNECT = 0
-ABSOLUTE int_EVENT_RESELECT = 0
-ABSOLUTE int_EVENT_COMPLETE = 0
-ABSOLUTE int_EVENT_IDLE = 0
-ABSOLUTE int_EVENT_SELECT_FAILED = 0
-ABSOLUTE int_EVENT_BEFORE_SELECT = 0
-ABSOLUTE int_EVENT_RESELECT_FAILED = 0
-#endif
-
-ABSOLUTE NCR53c7xx_msg_abort = 0 ; Pointer to abort message
-ABSOLUTE NCR53c7xx_msg_reject = 0 ; Pointer to reject message
-ABSOLUTE NCR53c7xx_zero = 0 ; long with zero in it, use for source
-ABSOLUTE NCR53c7xx_sink = 0 ; long to dump worthless data in
-ABSOLUTE NOP_insn = 0 ; NOP instruction
-
-; Pointer to message, potentially multi-byte
-ABSOLUTE msg_buf = 0
-
-; Pointer to holding area for reselection information
-ABSOLUTE reselected_identify = 0
-ABSOLUTE reselected_tag = 0
-
-; Request sense command pointer, it's a 6 byte command, should
-; be constant for all commands since we always want 16 bytes of
-; sense and we don't need to change any fields as we did under
-; SCSI-I when we actually cared about the LUN field.
-;EXTERNAL NCR53c7xx_sense ; Request sense command
-
-#if (CHIP != 700) && (CHIP != 70066)
-; dsa_schedule
-; PURPOSE : after a DISCONNECT message has been received, and pointers
-; saved, insert the current DSA structure at the head of the
-; disconnected queue and fall through to the scheduler.
-;
-; CALLS : OK
-;
-; INPUTS : dsa - current DSA structure, reconnect_dsa_head - list
-; of disconnected commands
-;
-; MODIFIES : SCRATCH, reconnect_dsa_head
-;
-; EXITS : always passes control to schedule
-
-ENTRY dsa_schedule
-dsa_schedule:
-#ifdef DEBUG
- INT int_debug_dsa_schedule
-#endif
-
-;
-; Calculate the address of the next pointer within the DSA
-; structure of the command that is currently disconnecting
-;
-#if (CHIP == 710)
- ; Read what should be the current DSA from memory - actual DSA
- ; register is probably corrupt
- MOVE MEMORY 4, saved_dsa, addr_scratch
-#else
- CALL dsa_to_scratch
-#endif
- MOVE SCRATCH0 + dsa_next TO SCRATCH0
- MOVE SCRATCH1 + 0 TO SCRATCH1 WITH CARRY
- MOVE SCRATCH2 + 0 TO SCRATCH2 WITH CARRY
- MOVE SCRATCH3 + 0 TO SCRATCH3 WITH CARRY
-
-; Point the next field of this DSA structure at the current disconnected
-; list
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, dsa_schedule_insert + 8
- DMODE_MEMORY_TO_MEMORY
-dsa_schedule_insert:
- MOVE MEMORY 4, reconnect_dsa_head, 0
-
-; And update the head pointer.
-#if (CHIP == 710)
- ; Read what should be the current DSA from memory - actual DSA
- ; register is probably corrupt
- MOVE MEMORY 4, saved_dsa, addr_scratch
-#else
- CALL dsa_to_scratch
-#endif
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, reconnect_dsa_head
- DMODE_MEMORY_TO_MEMORY
-/* Temporarily, see what happens. */
-#ifndef ORIGINAL
-#if (CHIP != 710)
- MOVE SCNTL2 & 0x7f TO SCNTL2
-#endif
- CLEAR ACK
-#endif
-#if (CHIP == 710)
- ; Time to correct DSA following memory move
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
- WAIT DISCONNECT
-#ifdef EVENTS
- INT int_EVENT_DISCONNECT;
-#endif
-#ifdef DEBUG
- INT int_debug_disconnected
-#endif
- JUMP schedule
-#endif
-
-;
-; select
-;
-; PURPOSE : establish a nexus for the SCSI command referenced by DSA.
-; On success, the current DSA structure is removed from the issue
-; queue. Usually, this is entered as a fall-through from schedule,
-; although the contingent allegiance handling code will write
-; the select entry address to the DSP to restart a command as a
-; REQUEST SENSE. A message is sent (usually IDENTIFY, although
-; additional SDTR or WDTR messages may be sent). COMMAND OUT
-; is handled.
-;
-; INPUTS : DSA - SCSI command, issue_dsa_head
-;
-; CALLS : NOT OK
-;
-; MODIFIES : SCRATCH, issue_dsa_head
-;
-; EXITS : on reselection or selection, go to select_failed
-; otherwise, RETURN so control is passed back to
-; dsa_begin.
-;
-
-ENTRY select
-select:
-
-#ifdef EVENTS
- INT int_EVENT_BEFORE_SELECT
-#endif
-
-#ifdef DEBUG
- INT int_debug_scheduled
-#endif
- CLEAR TARGET
-
-; XXX
-;
-; In effect, SELECTION operations are backgrounded, with execution
-; continuing until code which waits for REQ or a fatal interrupt is
-; encountered.
-;
-; So, for more performance, we could overlap the code which removes
-; the command from the NCRs issue queue with the selection, but
-; at this point I don't want to deal with the error recovery.
-;
-
-#if (CHIP != 700) && (CHIP != 70066)
-#if (CHIP == 710)
- ; Enable selection timer
-#ifdef NO_SELECTION_TIMEOUT
- MOVE CTEST7 & 0xff TO CTEST7
-#else
- MOVE CTEST7 & 0xef TO CTEST7
-#endif
-#endif
- SELECT ATN FROM dsa_select, select_failed
- JUMP select_msgout, WHEN MSG_OUT
-ENTRY select_msgout
-select_msgout:
-#if (CHIP == 710)
- ; Disable selection timer
- MOVE CTEST7 | 0x10 TO CTEST7
-#endif
- MOVE FROM dsa_msgout, WHEN MSG_OUT
-#else
-ENTRY select_msgout
- SELECT ATN 0, select_failed
-select_msgout:
- MOVE 0, 0, WHEN MSGOUT
-#endif
-
-#ifdef EVENTS
- INT int_EVENT_SELECT
-#endif
- RETURN
-
-;
-; select_done
-;
-; PURPOSE: continue on to normal data transfer; called as the exit
-; point from dsa_begin.
-;
-; INPUTS: dsa
-;
-; CALLS: OK
-;
-;
-
-select_done:
-#if (CHIP == 710)
-; NOTE DSA is corrupt when we arrive here!
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
-
-#ifdef DEBUG
-ENTRY select_check_dsa
-select_check_dsa:
- INT int_debug_check_dsa
-#endif
-
-; After a successful selection, we should get either a CMD phase or
-; some transfer request negotiation message.
-
- JUMP cmdout, WHEN CMD
- INT int_err_unexpected_phase, WHEN NOT MSG_IN
-
-select_msg_in:
- CALL msg_in, WHEN MSG_IN
- JUMP select_msg_in, WHEN MSG_IN
-
-cmdout:
- INT int_err_unexpected_phase, WHEN NOT CMD
-#if (CHIP == 700)
- INT int_norm_selected
-#endif
-ENTRY cmdout_cmdout
-cmdout_cmdout:
-#if (CHIP != 700) && (CHIP != 70066)
- MOVE FROM dsa_cmdout, WHEN CMD
-#else
- MOVE 0, 0, WHEN CMD
-#endif /* (CHIP != 700) && (CHIP != 70066) */
-
-;
-; data_transfer
-; other_out
-; other_in
-; other_transfer
-;
-; PURPOSE : handle the main data transfer for a SCSI command in
-; several parts. In the first part, data_transfer, DATA_IN
-; and DATA_OUT phases are allowed, with the user provided
-; code (usually dynamically generated based on the scatter/gather
-; list associated with a SCSI command) called to handle these
-; phases.
-;
-; After control has passed to one of the user provided
-; DATA_IN or DATA_OUT routines, back calls are made to
-; other_transfer_in or other_transfer_out to handle non-DATA IN
-; and DATA OUT phases respectively, with the state of the active
-; data pointer being preserved in TEMP.
-;
-; On completion, the user code passes control to other_transfer
-; which causes DATA_IN and DATA_OUT to result in unexpected_phase
-; interrupts so that data overruns may be trapped.
-;
-; INPUTS : DSA - SCSI command
-;
-; CALLS : OK in data_transfer_start, not ok in other_out and other_in, ok in
-; other_transfer
-;
-; MODIFIES : SCRATCH
-;
-; EXITS : if STATUS IN is detected, signifying command completion,
-; the NCR jumps to command_complete. If MSG IN occurs, a
-; CALL is made to msg_in. Otherwise, other_transfer runs in
-; an infinite loop.
-;
-
-ENTRY data_transfer
-data_transfer:
- JUMP cmdout_cmdout, WHEN CMD
- CALL msg_in, WHEN MSG_IN
- INT int_err_unexpected_phase, WHEN MSG_OUT
- JUMP do_dataout, WHEN DATA_OUT
- JUMP do_datain, WHEN DATA_IN
- JUMP command_complete, WHEN STATUS
- JUMP data_transfer
-ENTRY end_data_transfer
-end_data_transfer:
-
-;
-; FIXME: On NCR53c700 and NCR53c700-66 chips, do_dataout/do_datain
-; should be fixed up whenever the nexus changes so it can point to the
-; correct routine for that command.
-;
-
-#if (CHIP != 700) && (CHIP != 70066)
-; Nasty jump to dsa->dataout
-do_dataout:
-#if (CHIP == 710)
- MOVE MEMORY 4, saved_dsa, addr_scratch
-#else
- CALL dsa_to_scratch
-#endif
- MOVE SCRATCH0 + dsa_dataout TO SCRATCH0
- MOVE SCRATCH1 + 0 TO SCRATCH1 WITH CARRY
- MOVE SCRATCH2 + 0 TO SCRATCH2 WITH CARRY
- MOVE SCRATCH3 + 0 TO SCRATCH3 WITH CARRY
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, dataout_to_jump + 4
- DMODE_MEMORY_TO_MEMORY
-dataout_to_jump:
- MOVE MEMORY 4, 0, dataout_jump + 4
-#if (CHIP == 710)
- ; Time to correct DSA following memory move
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
-dataout_jump:
- JUMP 0
-
-; Nasty jump to dsa->dsain
-do_datain:
-#if (CHIP == 710)
- MOVE MEMORY 4, saved_dsa, addr_scratch
-#else
- CALL dsa_to_scratch
-#endif
- MOVE SCRATCH0 + dsa_datain TO SCRATCH0
- MOVE SCRATCH1 + 0 TO SCRATCH1 WITH CARRY
- MOVE SCRATCH2 + 0 TO SCRATCH2 WITH CARRY
- MOVE SCRATCH3 + 0 TO SCRATCH3 WITH CARRY
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, datain_to_jump + 4
- DMODE_MEMORY_TO_MEMORY
-ENTRY datain_to_jump
-datain_to_jump:
- MOVE MEMORY 4, 0, datain_jump + 4
-#if (CHIP == 710)
- ; Time to correct DSA following memory move
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
-#ifdef DEBUG
- INT int_debug_datain
-#endif
-datain_jump:
- JUMP 0
-#endif /* (CHIP != 700) && (CHIP != 70066) */
-
-
-; Note that other_out and other_in loop until a non-data phase
-; is discovered, so we only execute return statements when we
-; can go on to the next data phase block move statement.
-
-ENTRY other_out
-other_out:
-#if 0
- INT 0x03ffdead
-#endif
- INT int_err_unexpected_phase, WHEN CMD
- JUMP msg_in_restart, WHEN MSG_IN
- INT int_err_unexpected_phase, WHEN MSG_OUT
- INT int_err_unexpected_phase, WHEN DATA_IN
- JUMP command_complete, WHEN STATUS
- JUMP other_out, WHEN NOT DATA_OUT
-#if (CHIP == 710)
-; TEMP should be OK, as we got here from a call in the user dataout code.
-#endif
- RETURN
-
-ENTRY other_in
-other_in:
-#if 0
- INT 0x03ffdead
-#endif
- INT int_err_unexpected_phase, WHEN CMD
- JUMP msg_in_restart, WHEN MSG_IN
- INT int_err_unexpected_phase, WHEN MSG_OUT
- INT int_err_unexpected_phase, WHEN DATA_OUT
- JUMP command_complete, WHEN STATUS
- JUMP other_in, WHEN NOT DATA_IN
-#if (CHIP == 710)
-; TEMP should be OK, as we got here from a call in the user datain code.
-#endif
- RETURN
-
-
-ENTRY other_transfer
-other_transfer:
- INT int_err_unexpected_phase, WHEN CMD
- CALL msg_in, WHEN MSG_IN
- INT int_err_unexpected_phase, WHEN MSG_OUT
- INT int_err_unexpected_phase, WHEN DATA_OUT
- INT int_err_unexpected_phase, WHEN DATA_IN
- JUMP command_complete, WHEN STATUS
- JUMP other_transfer
-
-;
-; msg_in_restart
-; msg_in
-; munge_msg
-;
-; PURPOSE : process messages from a target. msg_in is called when the
-; caller hasn't read the first byte of the message. munge_message
-; is called when the caller has read the first byte of the message,
-; and left it in SFBR. msg_in_restart is called when the caller
-; hasn't read the first byte of the message, and wishes RETURN
-; to transfer control back to the address of the conditional
-; CALL instruction rather than to the instruction after it.
-;
-; Various int_* interrupts are generated when the host system
-; needs to intervene, as is the case with SDTR, WDTR, and
-; INITIATE RECOVERY messages.
-;
-; When the host system handles one of these interrupts,
-; it can respond by reentering at reject_message,
-; which rejects the message and returns control to
-; the caller of msg_in or munge_msg, accept_message
-; which clears ACK and returns control, or reply_message
-; which sends the message pointed to by the DSA
-; msgout_other table indirect field.
-;
-; DISCONNECT messages are handled by moving the command
-; to the reconnect_dsa_queue.
-#if (CHIP == 710)
-; NOTE: DSA should be valid when we get here - we cannot save both it
-; and TEMP in this routine.
-#endif
-;
-; INPUTS : DSA - SCSI COMMAND, SFBR - first byte of message (munge_msg
-; only)
-;
-; CALLS : NO. The TEMP register isn't backed up to allow nested calls.
-;
-; MODIFIES : SCRATCH, DSA on DISCONNECT
-;
-; EXITS : On receipt of SAVE DATA POINTER, RESTORE POINTERS,
-; and normal return from message handlers running under
-; Linux, control is returned to the caller. Receipt
-; of DISCONNECT messages pass control to dsa_schedule.
-;
-ENTRY msg_in_restart
-msg_in_restart:
-; XXX - hackish
-;
-; Since it's easier to debug changes to the statically
-; compiled code, rather than the dynamically generated
-; stuff, such as
-;
-; MOVE x, y, WHEN data_phase
-; CALL other_z, WHEN NOT data_phase
-; MOVE x, y, WHEN data_phase
-;
-; I'd like to have certain routines (notably the message handler)
-; restart on the conditional call rather than the next instruction.
-;
-; So, subtract 8 from the return address
-
- MOVE TEMP0 + 0xf8 TO TEMP0
- MOVE TEMP1 + 0xff TO TEMP1 WITH CARRY
- MOVE TEMP2 + 0xff TO TEMP2 WITH CARRY
- MOVE TEMP3 + 0xff TO TEMP3 WITH CARRY
-
-ENTRY msg_in
-msg_in:
- MOVE 1, msg_buf, WHEN MSG_IN
-
-munge_msg:
- JUMP munge_extended, IF 0x01 ; EXTENDED MESSAGE
- JUMP munge_2, IF 0x20, AND MASK 0xdf ; two byte message
-;
-; XXX - I've seen a handful of broken SCSI devices which fail to issue
-; a SAVE POINTERS message before disconnecting in the middle of
-; a transfer, assuming that the DATA POINTER will be implicitly
-; restored.
-;
-; Historically, I've often done an implicit save when the DISCONNECT
-; message is processed. We may want to consider having the option of
-; doing that here.
-;
- JUMP munge_save_data_pointer, IF 0x02 ; SAVE DATA POINTER
- JUMP munge_restore_pointers, IF 0x03 ; RESTORE POINTERS
- JUMP munge_disconnect, IF 0x04 ; DISCONNECT
- INT int_msg_1, IF 0x07 ; MESSAGE REJECT
- INT int_msg_1, IF 0x0f ; INITIATE RECOVERY
-#ifdef EVENTS
- INT int_EVENT_SELECT_FAILED
-#endif
- JUMP reject_message
-
-munge_2:
- JUMP reject_message
-;
-; The SCSI standard allows targets to recover from transient
-; error conditions by backing up the data pointer with a
-; RESTORE POINTERS message.
-;
-; So, we must save and restore the _residual_ code as well as
-; the current instruction pointer. Because of this messiness,
-; it is simpler to put dynamic code in the dsa for this and to
-; just do a simple jump down there.
-;
-
-munge_save_data_pointer:
-#if (CHIP == 710)
- ; We have something in TEMP here, so first we must save that
- MOVE TEMP0 TO SFBR
- MOVE SFBR TO SCRATCH0
- MOVE TEMP1 TO SFBR
- MOVE SFBR TO SCRATCH1
- MOVE TEMP2 TO SFBR
- MOVE SFBR TO SCRATCH2
- MOVE TEMP3 TO SFBR
- MOVE SFBR TO SCRATCH3
- MOVE MEMORY 4, addr_scratch, jump_temp + 4
- ; Now restore DSA
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
- MOVE DSA0 + dsa_save_data_pointer TO SFBR
- MOVE SFBR TO SCRATCH0
- MOVE DSA1 + 0xff TO SFBR WITH CARRY
- MOVE SFBR TO SCRATCH1
- MOVE DSA2 + 0xff TO SFBR WITH CARRY
- MOVE SFBR TO SCRATCH2
- MOVE DSA3 + 0xff TO SFBR WITH CARRY
- MOVE SFBR TO SCRATCH3
-
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, jump_dsa_save + 4
- DMODE_MEMORY_TO_MEMORY
-jump_dsa_save:
- JUMP 0
-
-munge_restore_pointers:
-#if (CHIP == 710)
- ; The code at dsa_restore_pointers will RETURN, but we don't care
- ; about TEMP here, as it will overwrite it anyway.
-#endif
- MOVE DSA0 + dsa_restore_pointers TO SFBR
- MOVE SFBR TO SCRATCH0
- MOVE DSA1 + 0xff TO SFBR WITH CARRY
- MOVE SFBR TO SCRATCH1
- MOVE DSA2 + 0xff TO SFBR WITH CARRY
- MOVE SFBR TO SCRATCH2
- MOVE DSA3 + 0xff TO SFBR WITH CARRY
- MOVE SFBR TO SCRATCH3
-
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, jump_dsa_restore + 4
- DMODE_MEMORY_TO_MEMORY
-jump_dsa_restore:
- JUMP 0
-
-
-munge_disconnect:
-#ifdef DEBUG
- INT int_debug_disconnect_msg
-#endif
-
-/*
- * Before, we overlapped processing with waiting for disconnect, but
- * debugging was beginning to appear messy. Temporarily move things
- * to just before the WAIT DISCONNECT.
- */
-
-#ifdef ORIGINAL
-#if (CHIP == 710)
-; Following clears Unexpected Disconnect bit. What do we do?
-#else
- MOVE SCNTL2 & 0x7f TO SCNTL2
-#endif
- CLEAR ACK
-#endif
-
-#if (CHIP != 700) && (CHIP != 70066)
- JUMP dsa_schedule
-#else
- WAIT DISCONNECT
- INT int_norm_disconnected
-#endif
-
-munge_extended:
- CLEAR ACK
- INT int_err_unexpected_phase, WHEN NOT MSG_IN
- MOVE 1, msg_buf + 1, WHEN MSG_IN
- JUMP munge_extended_2, IF 0x02
- JUMP munge_extended_3, IF 0x03
- JUMP reject_message
-
-munge_extended_2:
- CLEAR ACK
- MOVE 1, msg_buf + 2, WHEN MSG_IN
- JUMP reject_message, IF NOT 0x02 ; Must be WDTR
- CLEAR ACK
- MOVE 1, msg_buf + 3, WHEN MSG_IN
- INT int_msg_wdtr
-
-munge_extended_3:
- CLEAR ACK
- MOVE 1, msg_buf + 2, WHEN MSG_IN
- JUMP reject_message, IF NOT 0x01 ; Must be SDTR
- CLEAR ACK
- MOVE 2, msg_buf + 3, WHEN MSG_IN
- INT int_msg_sdtr
-
-ENTRY reject_message
-reject_message:
- SET ATN
- CLEAR ACK
- MOVE 1, NCR53c7xx_msg_reject, WHEN MSG_OUT
- RETURN
-
-ENTRY accept_message
-accept_message:
- CLEAR ATN
- CLEAR ACK
- RETURN
-
-ENTRY respond_message
-respond_message:
- SET ATN
- CLEAR ACK
- MOVE FROM dsa_msgout_other, WHEN MSG_OUT
- RETURN
-
-;
-; command_complete
-;
-; PURPOSE : handle command termination when STATUS IN is detected by reading
-; a status byte followed by a command termination message.
-;
-; Normal termination results in an INTFLY instruction, and
-; the host system can pick out which command terminated by
-; examining the MESSAGE and STATUS buffers of all currently
-; executing commands;
-;
-; Abnormal (CHECK_CONDITION) termination results in an
-; int_err_check_condition interrupt so that a REQUEST SENSE
-; command can be issued out-of-order so that no other command
-; clears the contingent allegiance condition.
-;
-;
-; INPUTS : DSA - command
-;
-; CALLS : OK
-;
-; EXITS : On successful termination, control is passed to schedule.
-; On abnormal termination, the user will usually modify the
-; DSA fields and corresponding buffers and return control
-; to select.
-;
-
-ENTRY command_complete
-command_complete:
- MOVE FROM dsa_status, WHEN STATUS
-#if (CHIP != 700) && (CHIP != 70066)
- MOVE SFBR TO SCRATCH0 ; Save status
-#endif /* (CHIP != 700) && (CHIP != 70066) */
-ENTRY command_complete_msgin
-command_complete_msgin:
- MOVE FROM dsa_msgin, WHEN MSG_IN
-; Indicate that we should be expecting a disconnect
-#if (CHIP != 710)
- MOVE SCNTL2 & 0x7f TO SCNTL2
-#else
- ; Above code cleared the Unexpected Disconnect bit, what do we do?
-#endif
- CLEAR ACK
-#if (CHIP != 700) && (CHIP != 70066)
- WAIT DISCONNECT
-
-;
-; The SCSI specification states that when a UNIT ATTENTION condition
-; is pending, as indicated by a CHECK CONDITION status message,
-; the target shall revert to asynchronous transfers. Since
-; synchronous transfers parameters are maintained on a per INITIATOR/TARGET
-; basis, and returning control to our scheduler could work on a command
-; running on another lun on that target using the old parameters, we must
-; interrupt the host processor to get them changed, or change them ourselves.
-;
-; Once SCSI-II tagged queueing is implemented, things will be even more
-; hairy, since contingent allegiance conditions exist on a per-target/lun
-; basis, and issuing a new command with a different tag would clear it.
-; In these cases, we must interrupt the host processor to get a request
-; added to the HEAD of the queue with the request sense command, or we
-; must automatically issue the request sense command.
-
-#if 0
- MOVE SCRATCH0 TO SFBR
- JUMP command_failed, IF 0x02
-#endif
-#if (CHIP == 710)
-#if defined(MVME16x_INTFLY)
-; For MVME16x (ie CHIP=710) we will force an INTFLY by triggering a software
-; interrupt (SW7). We can use SCRATCH, as we are about to jump to
-; schedule, which corrupts it anyway. Will probably remove this later,
-; but want to check performance effects first.
-
-#define INTFLY_ADDR 0xfff40070
-
- MOVE 0 TO SCRATCH0
- MOVE 0x80 TO SCRATCH1
- MOVE 0 TO SCRATCH2
- MOVE 0 TO SCRATCH3
- MOVE MEMORY 4, addr_scratch, INTFLY_ADDR
-#else
- INT int_norm_emulateintfly
-#endif
-#else
- INTFLY
-#endif
-#endif /* (CHIP != 700) && (CHIP != 70066) */
-#if (CHIP == 710)
- ; Time to correct DSA following memory move
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
-#ifdef EVENTS
- INT int_EVENT_COMPLETE
-#endif
-#if (CHIP != 700) && (CHIP != 70066)
- JUMP schedule
-command_failed:
- INT int_err_check_condition
-#else
- INT int_norm_command_complete
-#endif
-
-;
-; wait_reselect
-;
-; PURPOSE : This is essentially the idle routine, where control lands
-; when there are no new processes to schedule. wait_reselect
-; waits for reselection, selection, and new commands.
-;
-; When a successful reselection occurs, with the aid
-; of fixed up code in each DSA, wait_reselect walks the
-; reconnect_dsa_queue, asking each dsa if the target ID
-; and LUN match its.
-;
-; If a match is found, a call is made back to reselected_ok,
-; which through the miracles of self modifying code, extracts
-; the found DSA from the reconnect_dsa_queue and then
-; returns control to the DSAs thread of execution.
-;
-; INPUTS : NONE
-;
-; CALLS : OK
-;
-; MODIFIES : DSA,
-;
-; EXITS : On successful reselection, control is returned to the
-; DSA which called reselected_ok. If the WAIT RESELECT
-; was interrupted by a new commands arrival signaled by
-; SIG_P, control is passed to schedule. If the NCR is
-; selected, the host system is interrupted with an
-; int_err_selected which is usually responded to by
-; setting DSP to the target_abort address.
-
-ENTRY wait_reselect
-wait_reselect:
-#ifdef EVENTS
- int int_EVENT_IDLE
-#endif
-#ifdef DEBUG
- int int_debug_idle
-#endif
- WAIT RESELECT wait_reselect_failed
-
-reselected:
-#ifdef EVENTS
- int int_EVENT_RESELECT
-#endif
- CLEAR TARGET
- DMODE_MEMORY_TO_MEMORY
- ; Read all data needed to reestablish the nexus -
- MOVE 1, reselected_identify, WHEN MSG_IN
- ; We used to CLEAR ACK here.
-#if (CHIP != 700) && (CHIP != 70066)
-#ifdef DEBUG
- int int_debug_reselected
-#endif
-
- ; Point DSA at the current head of the disconnected queue.
- DMODE_MEMORY_TO_NCR
- MOVE MEMORY 4, reconnect_dsa_head, addr_scratch
- DMODE_MEMORY_TO_MEMORY
-#if (CHIP == 710)
- MOVE MEMORY 4, addr_scratch, saved_dsa
-#else
- CALL scratch_to_dsa
-#endif
-
- ; Fix the update-next pointer so that the reconnect_dsa_head
- ; pointer is the one that will be updated if this DSA is a hit
- ; and we remove it from the queue.
-
- MOVE MEMORY 4, addr_reconnect_dsa_head, reselected_ok_patch + 8
-#if (CHIP == 710)
- ; Time to correct DSA following memory move
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
-
-ENTRY reselected_check_next
-reselected_check_next:
-#ifdef DEBUG
- INT int_debug_reselect_check
-#endif
- ; Check for a NULL pointer.
- MOVE DSA0 TO SFBR
- JUMP reselected_not_end, IF NOT 0
- MOVE DSA1 TO SFBR
- JUMP reselected_not_end, IF NOT 0
- MOVE DSA2 TO SFBR
- JUMP reselected_not_end, IF NOT 0
- MOVE DSA3 TO SFBR
- JUMP reselected_not_end, IF NOT 0
- INT int_err_unexpected_reselect
-
-reselected_not_end:
- ;
- ; XXX the ALU is only eight bits wide, and the assembler
- ; wont do the dirt work for us. As long as dsa_check_reselect
- ; is negative, we need to sign extend with 1 bits to the full
- ; 32 bit width of the address.
- ;
- ; A potential work around would be to have a known alignment
- ; of the DSA structure such that the base address plus
- ; dsa_check_reselect doesn't require carrying from bytes
- ; higher than the LSB.
- ;
-
- MOVE DSA0 TO SFBR
- MOVE SFBR + dsa_check_reselect TO SCRATCH0
- MOVE DSA1 TO SFBR
- MOVE SFBR + 0xff TO SCRATCH1 WITH CARRY
- MOVE DSA2 TO SFBR
- MOVE SFBR + 0xff TO SCRATCH2 WITH CARRY
- MOVE DSA3 TO SFBR
- MOVE SFBR + 0xff TO SCRATCH3 WITH CARRY
-
- DMODE_NCR_TO_MEMORY
- MOVE MEMORY 4, addr_scratch, reselected_check + 4
- DMODE_MEMORY_TO_MEMORY
-#if (CHIP == 710)
- ; Time to correct DSA following memory move
- MOVE MEMORY 4, saved_dsa, addr_dsa
-#endif
-reselected_check:
- JUMP 0
-
-
-;
-;
-#if (CHIP == 710)
-; We have problems here - the memory move corrupts TEMP and DSA. This
-; routine is called from DSA code, and patched from many places. Scratch
-; is probably free when it is called.
-; We have to:
-; copy temp to scratch, one byte at a time
-; write scratch to patch a jump in place of the return
-; do the move memory
-; jump to the patched in return address
-; DSA is corrupt when we get here, and can be left corrupt
-
-ENTRY reselected_ok
-reselected_ok:
- MOVE TEMP0 TO SFBR
- MOVE SFBR TO SCRATCH0
- MOVE TEMP1 TO SFBR
- MOVE SFBR TO SCRATCH1
- MOVE TEMP2 TO SFBR
- MOVE SFBR TO SCRATCH2
- MOVE TEMP3 TO SFBR
- MOVE SFBR TO SCRATCH3
- MOVE MEMORY 4, addr_scratch, reselected_ok_jump + 4
-reselected_ok_patch:
- MOVE MEMORY 4, 0, 0
-reselected_ok_jump:
- JUMP 0
-#else
-ENTRY reselected_ok
-reselected_ok:
-reselected_ok_patch:
- MOVE MEMORY 4, 0, 0 ; Patched : first word
- ; is address of
- ; successful dsa_next
- ; Second word is last
- ; unsuccessful dsa_next,
- ; starting with
- ; dsa_reconnect_head
- ; We used to CLEAR ACK here.
-#ifdef DEBUG
- INT int_debug_reselected_ok
-#endif
-#ifdef DEBUG
- INT int_debug_check_dsa
-#endif
- RETURN ; Return control to where
-#endif
-#else
- INT int_norm_reselected
-#endif /* (CHIP != 700) && (CHIP != 70066) */
-
-selected:
- INT int_err_selected;
-
-;
-; A select or reselect failure can be caused by one of two conditions :
-; 1. SIG_P was set. This will be the case if the user has written
-; a new value to a previously NULL head of the issue queue.
-;
-; 2. The NCR53c810 was selected or reselected by another device.
-;
-; 3. The bus was already busy since we were selected or reselected
-; before starting the command.
-
-wait_reselect_failed:
-#ifdef EVENTS
- INT int_EVENT_RESELECT_FAILED
-#endif
-; Check selected bit.
-#if (CHIP == 710)
- ; Must work out how to tell if we are selected....
-#else
- MOVE SIST0 & 0x20 TO SFBR
- JUMP selected, IF 0x20
-#endif
-; Reading CTEST2 clears the SIG_P bit in the ISTAT register.
- MOVE CTEST2 & 0x40 TO SFBR
- JUMP schedule, IF 0x40
-; Check connected bit.
-; FIXME: this needs to change if we support target mode
- MOVE ISTAT & 0x08 TO SFBR
- JUMP reselected, IF 0x08
-; FIXME : Something bogus happened, and we shouldn't fail silently.
-#if 0
- JUMP schedule
-#else
- INT int_debug_panic
-#endif
-
-
-select_failed:
-#if (CHIP == 710)
- ; Disable selection timer
- MOVE CTEST7 | 0x10 TO CTEST7
-#endif
-#ifdef EVENTS
- int int_EVENT_SELECT_FAILED
-#endif
-; Otherwise, mask the selected and reselected bits off SIST0
-#if (CHIP ==710)
- ; Let's assume we don't get selected for now
- MOVE SSTAT0 & 0x10 TO SFBR
-#else
- MOVE SIST0 & 0x30 TO SFBR
- JUMP selected, IF 0x20
-#endif
- JUMP reselected, IF 0x10
-; If SIGP is set, the user just gave us another command, and
-; we should restart or return to the scheduler.
-; Reading CTEST2 clears the SIG_P bit in the ISTAT register.
- MOVE CTEST2 & 0x40 TO SFBR
- JUMP select, IF 0x40
-; Check connected bit.
-; FIXME: this needs to change if we support target mode
-; FIXME: is this really necessary?
- MOVE ISTAT & 0x08 TO SFBR
- JUMP reselected, IF 0x08
-; FIXME : Something bogus happened, and we shouldn't fail silently.
-#if 0
- JUMP schedule
-#else
- INT int_debug_panic
-#endif
-
-;
-; test_1
-; test_2
-;
-; PURPOSE : run some verification tests on the NCR. test_1
-; copies test_src to test_dest and interrupts the host
-; processor, testing for cache coherency and interrupt
-; problems in the processes.
-;
-; test_2 runs a command with offsets relative to the
-; DSA on entry, and is useful for miscellaneous experimentation.
-;
-
-; Verify that interrupts are working correctly and that we don't
-; have a cache invalidation problem.
-
-ABSOLUTE test_src = 0, test_dest = 0
-ENTRY test_1
-test_1:
- MOVE MEMORY 4, test_src, test_dest
- INT int_test_1
-
-;
-; Run arbitrary commands, with test code establishing a DSA
-;
-
-ENTRY test_2
-test_2:
- CLEAR TARGET
-#if (CHIP == 710)
- ; Enable selection timer
-#ifdef NO_SELECTION_TIMEOUT
- MOVE CTEST7 & 0xff TO CTEST7
-#else
- MOVE CTEST7 & 0xef TO CTEST7
-#endif
-#endif
- SELECT ATN FROM 0, test_2_fail
- JUMP test_2_msgout, WHEN MSG_OUT
-ENTRY test_2_msgout
-test_2_msgout:
-#if (CHIP == 710)
- ; Disable selection timer
- MOVE CTEST7 | 0x10 TO CTEST7
-#endif
- MOVE FROM 8, WHEN MSG_OUT
- MOVE FROM 16, WHEN CMD
- MOVE FROM 24, WHEN DATA_IN
- MOVE FROM 32, WHEN STATUS
- MOVE FROM 40, WHEN MSG_IN
-#if (CHIP != 710)
- MOVE SCNTL2 & 0x7f TO SCNTL2
-#endif
- CLEAR ACK
- WAIT DISCONNECT
-test_2_fail:
-#if (CHIP == 710)
- ; Disable selection timer
- MOVE CTEST7 | 0x10 TO CTEST7
-#endif
- INT int_test_2
-
-ENTRY debug_break
-debug_break:
- INT int_debug_break
-
-;
-; initiator_abort
-; target_abort
-;
-; PURPOSE : Abort the currently established nexus from with initiator
-; or target mode.
-;
-;
-
-ENTRY target_abort
-target_abort:
- SET TARGET
- DISCONNECT
- CLEAR TARGET
- JUMP schedule
-
-ENTRY initiator_abort
-initiator_abort:
- SET ATN
-;
-; The SCSI-I specification says that targets may go into MSG out at
-; their leisure upon receipt of the ATN single. On all versions of the
-; specification, we can't change phases until REQ transitions true->false,
-; so we need to sink/source one byte of data to allow the transition.
-;
-; For the sake of safety, we'll only source one byte of data in all
-; cases, but to accommodate the SCSI-I dain bramage, we'll sink an
-; arbitrary number of bytes.
- JUMP spew_cmd, WHEN CMD
- JUMP eat_msgin, WHEN MSG_IN
- JUMP eat_datain, WHEN DATA_IN
- JUMP eat_status, WHEN STATUS
- JUMP spew_dataout, WHEN DATA_OUT
- JUMP sated
-spew_cmd:
- MOVE 1, NCR53c7xx_zero, WHEN CMD
- JUMP sated
-eat_msgin:
- MOVE 1, NCR53c7xx_sink, WHEN MSG_IN
- JUMP eat_msgin, WHEN MSG_IN
- JUMP sated
-eat_status:
- MOVE 1, NCR53c7xx_sink, WHEN STATUS
- JUMP eat_status, WHEN STATUS
- JUMP sated
-eat_datain:
- MOVE 1, NCR53c7xx_sink, WHEN DATA_IN
- JUMP eat_datain, WHEN DATA_IN
- JUMP sated
-spew_dataout:
- MOVE 1, NCR53c7xx_zero, WHEN DATA_OUT
-sated:
-#if (CHIP != 710)
- MOVE SCNTL2 & 0x7f TO SCNTL2
-#endif
- MOVE 1, NCR53c7xx_msg_abort, WHEN MSG_OUT
- WAIT DISCONNECT
- INT int_norm_aborted
-
-#if (CHIP != 710)
-;
-; dsa_to_scratch
-; scratch_to_dsa
-;
-; PURPOSE :
-; The NCR chips cannot do a move memory instruction with the DSA register
-; as the source or destination. So, we provide a couple of subroutines
-; that let us switch between the DSA register and scratch register.
-;
-; Memory moves to/from the DSPS register also don't work, but we
-; don't use them.
-;
-;
-
-
-dsa_to_scratch:
- MOVE DSA0 TO SFBR
- MOVE SFBR TO SCRATCH0
- MOVE DSA1 TO SFBR
- MOVE SFBR TO SCRATCH1
- MOVE DSA2 TO SFBR
- MOVE SFBR TO SCRATCH2
- MOVE DSA3 TO SFBR
- MOVE SFBR TO SCRATCH3
- RETURN
-
-scratch_to_dsa:
- MOVE SCRATCH0 TO SFBR
- MOVE SFBR TO DSA0
- MOVE SCRATCH1 TO SFBR
- MOVE SFBR TO DSA1
- MOVE SCRATCH2 TO SFBR
- MOVE SFBR TO DSA2
- MOVE SCRATCH3 TO SFBR
- MOVE SFBR TO DSA3
- RETURN
-#endif
-
-#if (CHIP == 710)
-; Little patched jump, used to overcome problems with TEMP getting
-; corrupted on memory moves.
-
-jump_temp:
- JUMP 0
-#endif