1592 lines
46 KiB
Plaintext
1592 lines
46 KiB
Plaintext
#undef DEBUG
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#undef EVENTS
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#undef NO_SELECTION_TIMEOUT
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#define BIG_ENDIAN
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; 53c710 driver. Modified from Drew Eckhardts driver
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; for 53c810 by Richard Hirst [richard@sleepie.demon.co.uk]
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;
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; I have left the script for the 53c8xx family in here, as it is likely
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; to be useful to see what I changed when bug hunting.
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; NCR 53c810 driver, main script
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; Sponsored by
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; iX Multiuser Multitasking Magazine
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; hm@ix.de
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;
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; Copyright 1993, 1994, 1995 Drew Eckhardt
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; Visionary Computing
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; (Unix and Linux consulting and custom programming)
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; drew@PoohSticks.ORG
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; +1 (303) 786-7975
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;
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; TolerANT and SCSI SCRIPTS are registered trademarks of NCR Corporation.
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;
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; PRE-ALPHA
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;
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; For more information, please consult
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;
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; NCR 53C810
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; PCI-SCSI I/O Processor
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; Data Manual
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;
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; NCR 53C710
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; SCSI I/O Processor
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; Programmers Guide
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;
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; NCR Microelectronics
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; 1635 Aeroplaza Drive
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; Colorado Springs, CO 80916
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; 1+ (719) 578-3400
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;
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; Toll free literature number
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; +1 (800) 334-5454
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;
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; IMPORTANT : This code is self modifying due to the limitations of
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; the NCR53c7,8xx series chips. Persons debugging this code with
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; the remote debugger should take this into account, and NOT set
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; breakpoints in modified instructions.
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;
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; Design:
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; The NCR53c7,8xx family of SCSI chips are busmasters with an onboard
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; microcontroller using a simple instruction set.
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;
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; So, to minimize the effects of interrupt latency, and to maximize
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; throughput, this driver offloads the practical maximum amount
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; of processing to the SCSI chip while still maintaining a common
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; structure.
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;
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; Where tradeoffs were needed between efficiency on the older
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; chips and the newer NCR53c800 series, the NCR53c800 series
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; was chosen.
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;
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; While the NCR53c700 and NCR53c700-66 lacked the facilities to fully
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; automate SCSI transfers without host processor intervention, this
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; isn't the case with the NCR53c710 and newer chips which allow
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;
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; - reads and writes to the internal registers from within the SCSI
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; scripts, allowing the SCSI SCRIPTS(tm) code to save processor
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; state so that multiple threads of execution are possible, and also
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; provide an ALU for loop control, etc.
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;
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; - table indirect addressing for some instructions. This allows
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; pointers to be located relative to the DSA ((Data Structure
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; Address) register.
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;
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; These features make it possible to implement a mailbox style interface,
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; where the same piece of code is run to handle I/O for multiple threads
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; at once minimizing our need to relocate code. Since the NCR53c700/
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; NCR53c800 series have a unique combination of features, making a
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; a standard ingoing/outgoing mailbox system, costly, I've modified it.
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;
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; - Mailboxes are a mixture of code and data. This lets us greatly
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; simplify the NCR53c810 code and do things that would otherwise
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; not be possible.
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;
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; The saved data pointer is now implemented as follows :
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;
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; Control flow has been architected such that if control reaches
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; munge_save_data_pointer, on a restore pointers message or
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; reconnection, a jump to the address formerly in the TEMP register
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; will allow the SCSI command to resume execution.
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;
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;
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; Note : the DSA structures must be aligned on 32 bit boundaries,
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; since the source and destination of MOVE MEMORY instructions
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; must share the same alignment and this is the alignment of the
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; NCR registers.
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;
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; For some systems (MVME166, for example) dmode is always the same, so don't
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; waste time writing it
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#if 1
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#define DMODE_MEMORY_TO_NCR
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#define DMODE_MEMORY_TO_MEMORY
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#define DMODE_NCR_TO_MEMORY
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#else
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#define DMODE_MEMORY_TO_NCR MOVE dmode_memory_to_ncr TO DMODE
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#define DMODE_MEMORY_TO_MEMORY MOVE dmode_memory_to_memory TO DMODE
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#define DMODE_NCR_TO_MEMORY MOVE dmode_ncr_to_memory TO DMODE
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#endif
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ABSOLUTE dsa_temp_lun = 0 ; Patch to lun for current dsa
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ABSOLUTE dsa_temp_next = 0 ; Patch to dsa next for current dsa
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ABSOLUTE dsa_temp_addr_next = 0 ; Patch to address of dsa next address
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; for current dsa
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ABSOLUTE dsa_temp_sync = 0 ; Patch to address of per-target
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; sync routine
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ABSOLUTE dsa_sscf_710 = 0 ; Patch to address of per-target
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; sscf value (53c710)
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ABSOLUTE dsa_temp_target = 0 ; Patch to id for current dsa
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ABSOLUTE dsa_temp_addr_saved_pointer = 0; Patch to address of per-command
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; saved data pointer
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ABSOLUTE dsa_temp_addr_residual = 0 ; Patch to address of per-command
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; current residual code
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ABSOLUTE dsa_temp_addr_saved_residual = 0; Patch to address of per-command
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; saved residual code
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ABSOLUTE dsa_temp_addr_new_value = 0 ; Address of value for JUMP operand
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ABSOLUTE dsa_temp_addr_array_value = 0 ; Address to copy to
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ABSOLUTE dsa_temp_addr_dsa_value = 0 ; Address of this DSA value
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;
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; Once a device has initiated reselection, we need to compare it
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; against the singly linked list of commands which have disconnected
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; and are pending reselection. These commands are maintained in
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; an unordered singly linked list of DSA structures, through the
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; DSA pointers at their 'centers' headed by the reconnect_dsa_head
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; pointer.
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;
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; To avoid complications in removing commands from the list,
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; I minimize the amount of expensive (at eight operations per
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; addition @ 500-600ns each) pointer operations which must
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; be done in the NCR driver by precomputing them on the
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; host processor during dsa structure generation.
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;
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; The fixed-up per DSA code knows how to recognize the nexus
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; associated with the corresponding SCSI command, and modifies
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; the source and destination pointers for the MOVE MEMORY
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; instruction which is executed when reselected_ok is called
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; to remove the command from the list. Similarly, DSA is
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; loaded with the address of the next DSA structure and
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; reselected_check_next is called if a failure occurs.
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;
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; Perhaps more concisely, the net effect of the mess is
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;
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; for (dsa = reconnect_dsa_head, dest = &reconnect_dsa_head,
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; src = NULL; dsa; dest = &dsa->next, dsa = dsa->next) {
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; src = &dsa->next;
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; if (target_id == dsa->id && target_lun == dsa->lun) {
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; *dest = *src;
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; break;
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; }
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; }
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;
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; if (!dsa)
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; error (int_err_unexpected_reselect);
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; else
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; longjmp (dsa->jump_resume, 0);
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;
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;
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#if (CHIP != 700) && (CHIP != 70066)
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; Define DSA structure used for mailboxes
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ENTRY dsa_code_template
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dsa_code_template:
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ENTRY dsa_code_begin
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dsa_code_begin:
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; RGH: Don't care about TEMP and DSA here
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DMODE_MEMORY_TO_NCR
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MOVE MEMORY 4, dsa_temp_addr_dsa_value, addr_scratch
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DMODE_MEMORY_TO_MEMORY
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#if (CHIP == 710)
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MOVE MEMORY 4, addr_scratch, saved_dsa
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; We are about to go and select the device, so must set SSCF bits
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MOVE MEMORY 4, dsa_sscf_710, addr_scratch
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#ifdef BIG_ENDIAN
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MOVE SCRATCH3 TO SFBR
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#else
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MOVE SCRATCH0 TO SFBR
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#endif
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MOVE SFBR TO SBCL
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MOVE MEMORY 4, saved_dsa, addr_dsa
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#else
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CALL scratch_to_dsa
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#endif
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CALL select
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; Handle the phase mismatch which may have resulted from the
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; MOVE FROM dsa_msgout if we returned here. The CLEAR ATN
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; may or may not be necessary, and we should update script_asm.pl
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; to handle multiple pieces.
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CLEAR ATN
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CLEAR ACK
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; Replace second operand with address of JUMP instruction dest operand
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; in schedule table for this DSA. Becomes dsa_jump_dest in 53c7,8xx.c.
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ENTRY dsa_code_fix_jump
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dsa_code_fix_jump:
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MOVE MEMORY 4, NOP_insn, 0
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JUMP select_done
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; wrong_dsa loads the DSA register with the value of the dsa_next
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; field.
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;
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wrong_dsa:
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#if (CHIP == 710)
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; NOTE DSA is corrupt when we arrive here!
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#endif
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; Patch the MOVE MEMORY INSTRUCTION such that
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; the destination address is the address of the OLD
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; next pointer.
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;
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MOVE MEMORY 4, dsa_temp_addr_next, reselected_ok_patch + 8
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DMODE_MEMORY_TO_NCR
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;
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; Move the _contents_ of the next pointer into the DSA register as
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; the next I_T_L or I_T_L_Q tupple to check against the established
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; nexus.
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;
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MOVE MEMORY 4, dsa_temp_next, addr_scratch
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DMODE_MEMORY_TO_MEMORY
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#if (CHIP == 710)
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MOVE MEMORY 4, addr_scratch, saved_dsa
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MOVE MEMORY 4, saved_dsa, addr_dsa
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#else
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CALL scratch_to_dsa
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#endif
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JUMP reselected_check_next
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ABSOLUTE dsa_save_data_pointer = 0
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ENTRY dsa_code_save_data_pointer
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dsa_code_save_data_pointer:
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#if (CHIP == 710)
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; When we get here, TEMP has been saved in jump_temp+4, DSA is corrupt
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; We MUST return with DSA correct
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MOVE MEMORY 4, jump_temp+4, dsa_temp_addr_saved_pointer
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; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
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MOVE MEMORY 24, dsa_temp_addr_residual, dsa_temp_addr_saved_residual
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CLEAR ACK
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#ifdef DEBUG
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INT int_debug_saved
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#endif
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MOVE MEMORY 4, saved_dsa, addr_dsa
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JUMP jump_temp
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#else
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DMODE_NCR_TO_MEMORY
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MOVE MEMORY 4, addr_temp, dsa_temp_addr_saved_pointer
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DMODE_MEMORY_TO_MEMORY
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; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
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MOVE MEMORY 24, dsa_temp_addr_residual, dsa_temp_addr_saved_residual
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CLEAR ACK
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#ifdef DEBUG
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INT int_debug_saved
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#endif
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RETURN
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#endif
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ABSOLUTE dsa_restore_pointers = 0
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ENTRY dsa_code_restore_pointers
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dsa_code_restore_pointers:
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#if (CHIP == 710)
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; TEMP and DSA are corrupt when we get here, but who cares!
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MOVE MEMORY 4, dsa_temp_addr_saved_pointer, jump_temp + 4
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; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
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MOVE MEMORY 24, dsa_temp_addr_saved_residual, dsa_temp_addr_residual
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CLEAR ACK
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; Restore DSA, note we don't care about TEMP
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MOVE MEMORY 4, saved_dsa, addr_dsa
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#ifdef DEBUG
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INT int_debug_restored
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#endif
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JUMP jump_temp
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#else
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DMODE_MEMORY_TO_NCR
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MOVE MEMORY 4, dsa_temp_addr_saved_pointer, addr_temp
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DMODE_MEMORY_TO_MEMORY
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; HARD CODED : 24 bytes needs to agree with 53c7,8xx.h
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MOVE MEMORY 24, dsa_temp_addr_saved_residual, dsa_temp_addr_residual
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CLEAR ACK
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#ifdef DEBUG
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INT int_debug_restored
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#endif
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RETURN
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#endif
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ABSOLUTE dsa_check_reselect = 0
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; dsa_check_reselect determines whether or not the current target and
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; lun match the current DSA
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ENTRY dsa_code_check_reselect
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dsa_code_check_reselect:
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#if (CHIP == 710)
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/* Arrives here with DSA correct */
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/* Assumes we are always ID 7 */
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MOVE LCRC TO SFBR ; LCRC has our ID and his ID bits set
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JUMP REL (wrong_dsa), IF NOT dsa_temp_target, AND MASK 0x80
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#else
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MOVE SSID TO SFBR ; SSID contains 3 bit target ID
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; FIXME : we need to accommodate bit fielded and binary here for '7xx/'8xx chips
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JUMP REL (wrong_dsa), IF NOT dsa_temp_target, AND MASK 0xf8
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#endif
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;
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; Hack - move to scratch first, since SFBR is not writeable
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; via the CPU and hence a MOVE MEMORY instruction.
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;
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DMODE_MEMORY_TO_NCR
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MOVE MEMORY 1, reselected_identify, addr_scratch
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DMODE_MEMORY_TO_MEMORY
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#ifdef BIG_ENDIAN
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; BIG ENDIAN ON MVME16x
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MOVE SCRATCH3 TO SFBR
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#else
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MOVE SCRATCH0 TO SFBR
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#endif
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; FIXME : we need to accommodate bit fielded and binary here for '7xx/'8xx chips
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; Are you sure about that? richard@sleepie.demon.co.uk
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JUMP REL (wrong_dsa), IF NOT dsa_temp_lun, AND MASK 0xf8
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; Patch the MOVE MEMORY INSTRUCTION such that
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; the source address is the address of this dsa's
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; next pointer.
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MOVE MEMORY 4, dsa_temp_addr_next, reselected_ok_patch + 4
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CALL reselected_ok
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#if (CHIP == 710)
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; Restore DSA following memory moves in reselected_ok
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; dsa_temp_sync doesn't really care about DSA, but it has an
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; optional debug INT so a valid DSA is a good idea.
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MOVE MEMORY 4, saved_dsa, addr_dsa
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#endif
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CALL dsa_temp_sync
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; Release ACK on the IDENTIFY message _after_ we've set the synchronous
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; transfer parameters!
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CLEAR ACK
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; Implicitly restore pointers on reselection, so a RETURN
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; will transfer control back to the right spot.
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CALL REL (dsa_code_restore_pointers)
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RETURN
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ENTRY dsa_zero
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dsa_zero:
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ENTRY dsa_code_template_end
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dsa_code_template_end:
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; Perform sanity check for dsa_fields_start == dsa_code_template_end -
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; dsa_zero, puke.
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ABSOLUTE dsa_fields_start = 0 ; Sanity marker
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; pad 48 bytes (fix this RSN)
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ABSOLUTE dsa_next = 48 ; len 4 Next DSA
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; del 4 Previous DSA address
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ABSOLUTE dsa_cmnd = 56 ; len 4 Scsi_Cmnd * for this thread.
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ABSOLUTE dsa_select = 60 ; len 4 Device ID, Period, Offset for
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; table indirect select
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ABSOLUTE dsa_msgout = 64 ; len 8 table indirect move parameter for
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; select message
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ABSOLUTE dsa_cmdout = 72 ; len 8 table indirect move parameter for
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; command
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ABSOLUTE dsa_dataout = 80 ; len 4 code pointer for dataout
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ABSOLUTE dsa_datain = 84 ; len 4 code pointer for datain
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ABSOLUTE dsa_msgin = 88 ; len 8 table indirect move for msgin
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ABSOLUTE dsa_status = 96 ; len 8 table indirect move for status byte
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ABSOLUTE dsa_msgout_other = 104 ; len 8 table indirect for normal message out
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; (Synchronous transfer negotiation, etc).
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ABSOLUTE dsa_end = 112
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ABSOLUTE schedule = 0 ; Array of JUMP dsa_begin or JUMP (next),
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; terminated by a call to JUMP wait_reselect
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; Linked lists of DSA structures
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ABSOLUTE reconnect_dsa_head = 0 ; Link list of DSAs which can reconnect
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ABSOLUTE addr_reconnect_dsa_head = 0 ; Address of variable containing
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; address of reconnect_dsa_head
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; These select the source and destination of a MOVE MEMORY instruction
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ABSOLUTE dmode_memory_to_memory = 0x0
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ABSOLUTE dmode_memory_to_ncr = 0x0
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ABSOLUTE dmode_ncr_to_memory = 0x0
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ABSOLUTE addr_scratch = 0x0
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ABSOLUTE addr_temp = 0x0
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#if (CHIP == 710)
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ABSOLUTE saved_dsa = 0x0
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ABSOLUTE emulfly = 0x0
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ABSOLUTE addr_dsa = 0x0
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#endif
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#endif /* CHIP != 700 && CHIP != 70066 */
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; Interrupts -
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; MSB indicates type
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; 0 handle error condition
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; 1 handle message
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; 2 handle normal condition
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; 3 debugging interrupt
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; 4 testing interrupt
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; Next byte indicates specific error
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; XXX not yet implemented, I'm not sure if I want to -
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; Next byte indicates the routine the error occurred in
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; The LSB indicates the specific place the error occurred
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ABSOLUTE int_err_unexpected_phase = 0x00000000 ; Unexpected phase encountered
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ABSOLUTE int_err_selected = 0x00010000 ; SELECTED (nee RESELECTED)
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ABSOLUTE int_err_unexpected_reselect = 0x00020000
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ABSOLUTE int_err_check_condition = 0x00030000
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ABSOLUTE int_err_no_phase = 0x00040000
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ABSOLUTE int_msg_wdtr = 0x01000000 ; WDTR message received
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ABSOLUTE int_msg_sdtr = 0x01010000 ; SDTR received
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ABSOLUTE int_msg_1 = 0x01020000 ; single byte special message
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; received
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ABSOLUTE int_norm_select_complete = 0x02000000 ; Select complete, reprogram
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; registers.
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ABSOLUTE int_norm_reselect_complete = 0x02010000 ; Nexus established
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ABSOLUTE int_norm_command_complete = 0x02020000 ; Command complete
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ABSOLUTE int_norm_disconnected = 0x02030000 ; Disconnected
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ABSOLUTE int_norm_aborted =0x02040000 ; Aborted *dsa
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ABSOLUTE int_norm_reset = 0x02050000 ; Generated BUS reset.
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ABSOLUTE int_norm_emulateintfly = 0x02060000 ; 53C710 Emulated intfly
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ABSOLUTE int_debug_break = 0x03000000 ; Break point
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#ifdef DEBUG
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ABSOLUTE int_debug_scheduled = 0x03010000 ; new I/O scheduled
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ABSOLUTE int_debug_idle = 0x03020000 ; scheduler is idle
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ABSOLUTE int_debug_dsa_loaded = 0x03030000 ; dsa reloaded
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ABSOLUTE int_debug_reselected = 0x03040000 ; NCR reselected
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ABSOLUTE int_debug_head = 0x03050000 ; issue head overwritten
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ABSOLUTE int_debug_disconnected = 0x03060000 ; disconnected
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ABSOLUTE int_debug_disconnect_msg = 0x03070000 ; got message to disconnect
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ABSOLUTE int_debug_dsa_schedule = 0x03080000 ; in dsa_schedule
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ABSOLUTE int_debug_reselect_check = 0x03090000 ; Check for reselection of DSA
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ABSOLUTE int_debug_reselected_ok = 0x030a0000 ; Reselection accepted
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#endif
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ABSOLUTE int_debug_panic = 0x030b0000 ; Panic driver
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#ifdef DEBUG
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ABSOLUTE int_debug_saved = 0x030c0000 ; save/restore pointers
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ABSOLUTE int_debug_restored = 0x030d0000
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ABSOLUTE int_debug_sync = 0x030e0000 ; Sanity check synchronous
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; parameters.
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ABSOLUTE int_debug_datain = 0x030f0000 ; going into data in phase
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; 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
|