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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [drivers/] [scsi/] [atari_NCR5380.c] - Rev 1626
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/* * NCR 5380 generic driver routines. These should make it *trivial* * to implement 5380 SCSI drivers under Linux with a non-trantor * architecture. * * Note that these routines also work with NR53c400 family chips. * * Copyright 1993, Drew Eckhardt * Visionary Computing * (Unix and Linux consulting and custom programming) * drew@colorado.edu * +1 (303) 666-5836 * * DISTRIBUTION RELEASE 6. * * For more information, please consult * * NCR 5380 Family * SCSI Protocol Controller * Databook * * NCR Microelectronics * 1635 Aeroplaza Drive * Colorado Springs, CO 80916 * 1+ (719) 578-3400 * 1+ (800) 334-5454 */ /* * ++roman: To port the 5380 driver to the Atari, I had to do some changes in * this file, too: * * - Some of the debug statements were incorrect (undefined variables and the * like). I fixed that. * * - In information_transfer(), I think a #ifdef was wrong. Looking at the * possible DMA transfer size should also happen for REAL_DMA. I added this * in the #if statement. * * - When using real DMA, information_transfer() should return in a DATAOUT * phase after starting the DMA. It has nothing more to do. * * - The interrupt service routine should run main after end of DMA, too (not * only after RESELECTION interrupts). Additionally, it should _not_ test * for more interrupts after running main, since a DMA process may have * been started and interrupts are turned on now. The new int could happen * inside the execution of NCR5380_intr(), leading to recursive * calls. * * - I've added a function merge_consecutive_buffers() that tries to * merge scatter-gather buffers that are located at consecutive * physical addresses and can be processed with the same DMA setup. * Since most scatter-gather operations work on a page (4K) of * 4 buffers (1K), in more than 90% of all cases three interrupts and * DMA setup actions are saved. * * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA * and USLEEP, because these were messing up readability and will never be * needed for Atari SCSI. * * - I've revised the NCR5380_main() calling scheme (relax the 'main_running' * stuff), and 'main' is executed in a bottom half if awoken by an * interrupt. * * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..." * constructs. In my eyes, this made the source rather unreadable, so I * finally replaced that by the *_PRINTK() macros. * */ /* * Further development / testing that should be done : * 1. Test linked command handling code after Eric is ready with * the high level code. */ #if (NDEBUG & NDEBUG_LISTS) #define LIST(x,y) \ { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \ if ((x)==(y)) udelay(5); } #define REMOVE(w,x,y,z) \ { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \ (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \ if ((x)==(y)) udelay(5); } #else #define LIST(x,y) #define REMOVE(w,x,y,z) #endif #ifndef notyet #undef LINKED #endif /* * Design * Issues : * * The other Linux SCSI drivers were written when Linux was Intel PC-only, * and specifically for each board rather than each chip. This makes their * adaptation to platforms like the Mac (Some of which use NCR5380's) * more difficult than it has to be. * * Also, many of the SCSI drivers were written before the command queuing * routines were implemented, meaning their implementations of queued * commands were hacked on rather than designed in from the start. * * When I designed the Linux SCSI drivers I figured that * while having two different SCSI boards in a system might be useful * for debugging things, two of the same type wouldn't be used. * Well, I was wrong and a number of users have mailed me about running * multiple high-performance SCSI boards in a server. * * Finally, when I get questions from users, I have no idea what * revision of my driver they are running. * * This driver attempts to address these problems : * This is a generic 5380 driver. To use it on a different platform, * one simply writes appropriate system specific macros (ie, data * transfer - some PC's will use the I/O bus, 68K's must use * memory mapped) and drops this file in their 'C' wrapper. * * As far as command queueing, two queues are maintained for * each 5380 in the system - commands that haven't been issued yet, * and commands that are currently executing. This means that an * unlimited number of commands may be queued, letting * more commands propagate from the higher driver levels giving higher * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, * allowing multiple commands to propagate all the way to a SCSI-II device * while a command is already executing. * * To solve the multiple-boards-in-the-same-system problem, * there is a separate instance structure for each instance * of a 5380 in the system. So, multiple NCR5380 drivers will * be able to coexist with appropriate changes to the high level * SCSI code. * * A NCR5380_PUBLIC_REVISION macro is provided, with the release * number (updated for each public release) printed by the * NCR5380_print_options command, which should be called from the * wrapper detect function, so that I know what release of the driver * users are using. * * Issues specific to the NCR5380 : * * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead * piece of hardware that requires you to sit in a loop polling for * the REQ signal as long as you are connected. Some devices are * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect * while doing long seek operations. * * The workaround for this is to keep track of devices that have * disconnected. If the device hasn't disconnected, for commands that * should disconnect, we do something like * * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } * * Some tweaking of N and M needs to be done. An algorithm based * on "time to data" would give the best results as long as short time * to datas (ie, on the same track) were considered, however these * broken devices are the exception rather than the rule and I'd rather * spend my time optimizing for the normal case. * * Architecture : * * At the heart of the design is a coroutine, NCR5380_main, * which is started when not running by the interrupt handler, * timer, and queue command function. It attempts to establish * I_T_L or I_T_L_Q nexuses by removing the commands from the * issue queue and calling NCR5380_select() if a nexus * is not established. * * Once a nexus is established, the NCR5380_information_transfer() * phase goes through the various phases as instructed by the target. * if the target goes into MSG IN and sends a DISCONNECT message, * the command structure is placed into the per instance disconnected * queue, and NCR5380_main tries to find more work. If USLEEP * was defined, and the target is idle for too long, the system * will try to sleep. * * If a command has disconnected, eventually an interrupt will trigger, * calling NCR5380_intr() which will in turn call NCR5380_reselect * to reestablish a nexus. This will run main if necessary. * * On command termination, the done function will be called as * appropriate. * * SCSI pointers are maintained in the SCp field of SCSI command * structures, being initialized after the command is connected * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. * Note that in violation of the standard, an implicit SAVE POINTERS operation * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. */ /* * Using this file : * This file a skeleton Linux SCSI driver for the NCR 5380 series * of chips. To use it, you write a architecture specific functions * and macros and include this file in your driver. * * These macros control options : * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically * for commands that return with a CHECK CONDITION status. * * LINKED - if defined, linked commands are supported. * * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. * * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible * * These macros MUST be defined : * * NCR5380_read(register) - read from the specified register * * NCR5380_write(register, value) - write to the specific register * * Either real DMA *or* pseudo DMA may be implemented * REAL functions : * NCR5380_REAL_DMA should be defined if real DMA is to be used. * Note that the DMA setup functions should return the number of bytes * that they were able to program the controller for. * * Also note that generic i386/PC versions of these macros are * available as NCR5380_i386_dma_write_setup, * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. * * NCR5380_dma_write_setup(instance, src, count) - initialize * NCR5380_dma_read_setup(instance, dst, count) - initialize * NCR5380_dma_residual(instance); - residual count * * PSEUDO functions : * NCR5380_pwrite(instance, src, count) * NCR5380_pread(instance, dst, count); * * If nothing specific to this implementation needs doing (ie, with external * hardware), you must also define * * NCR5380_queue_command * NCR5380_reset * NCR5380_abort * NCR5380_proc_info * * to be the global entry points into the specific driver, ie * #define NCR5380_queue_command t128_queue_command. * * If this is not done, the routines will be defined as static functions * with the NCR5380* names and the user must provide a globally * accessible wrapper function. * * The generic driver is initialized by calling NCR5380_init(instance), * after setting the appropriate host specific fields and ID. If the * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, * possible) function may be used. Before the specific driver initialization * code finishes, NCR5380_print_options should be called. */ static struct Scsi_Host *first_instance = NULL; static Scsi_Host_Template *the_template = NULL; /* Macros ease life... :-) */ #define SETUP_HOSTDATA(in) \ struct NCR5380_hostdata *hostdata = \ (struct NCR5380_hostdata *)(in)->hostdata #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata) #define NEXT(cmd) ((Scsi_Cmnd *)((cmd)->host_scribble)) #define NEXTADDR(cmd) ((Scsi_Cmnd **)&((cmd)->host_scribble)) #define HOSTNO instance->host_no #define H_NO(cmd) (cmd)->host->host_no #ifdef SUPPORT_TAGS /* * Functions for handling tagged queuing * ===================================== * * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes: * * Using consecutive numbers for the tags is no good idea in my eyes. There * could be wrong re-usings if the counter (8 bit!) wraps and some early * command has been preempted for a long time. My solution: a bitfield for * remembering used tags. * * There's also the problem that each target has a certain queue size, but we * cannot know it in advance :-( We just see a QUEUE_FULL status being * returned. So, in this case, the driver internal queue size assumption is * reduced to the number of active tags if QUEUE_FULL is returned by the * target. The command is returned to the mid-level, but with status changed * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL * correctly. * * We're also not allowed running tagged commands as long as an untagged * command is active. And REQUEST SENSE commands after a contingent allegiance * condition _must_ be untagged. To keep track whether an untagged command has * been issued, the host->busy array is still employed, as it is without * support for tagged queuing. * * One could suspect that there are possible race conditions between * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(), * which already guaranteed to be running at most once. It is also the only * place where tags/LUNs are allocated. So no other allocation can slip * between that pair, there could only happen a reselection, which can free a * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes * important: the tag bit must be cleared before 'nr_allocated' is decreased. */ /* -1 for TAG_NONE is not possible with unsigned char cmd->tag */ #undef TAG_NONE #define TAG_NONE 0xff /* For the m68k, the number of bits in 'allocated' must be a multiple of 32! */ #if (MAX_TAGS % 32) != 0 #error "MAX_TAGS must be a multiple of 32!" #endif typedef struct { char allocated[MAX_TAGS/8]; int nr_allocated; int queue_size; } TAG_ALLOC; static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */ static void init_tags( void ) { int target, lun; TAG_ALLOC *ta; if (!setup_use_tagged_queuing) return; for( target = 0; target < 8; ++target ) { for( lun = 0; lun < 8; ++lun ) { ta = &TagAlloc[target][lun]; memset( &ta->allocated, 0, MAX_TAGS/8 ); ta->nr_allocated = 0; /* At the beginning, assume the maximum queue size we could * support (MAX_TAGS). This value will be decreased if the target * returns QUEUE_FULL status. */ ta->queue_size = MAX_TAGS; } } } /* Check if we can issue a command to this LUN: First see if the LUN is marked * busy by an untagged command. If the command should use tagged queuing, also * check that there is a free tag and the target's queue won't overflow. This * function should be called with interrupts disabled to avoid race * conditions. */ static int is_lun_busy( Scsi_Cmnd *cmd, int should_be_tagged ) { SETUP_HOSTDATA(cmd->host); if (hostdata->busy[cmd->target] & (1 << cmd->lun)) return( 1 ); if (!should_be_tagged || !setup_use_tagged_queuing || !cmd->device->tagged_supported) return( 0 ); if (TagAlloc[cmd->target][cmd->lun].nr_allocated >= TagAlloc[cmd->target][cmd->lun].queue_size ) { TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n", H_NO(cmd), cmd->target, cmd->lun ); return( 1 ); } return( 0 ); } /* Allocate a tag for a command (there are no checks anymore, check_lun_busy() * must be called before!), or reserve the LUN in 'busy' if the command is * untagged. */ static void cmd_get_tag( Scsi_Cmnd *cmd, int should_be_tagged ) { SETUP_HOSTDATA(cmd->host); /* If we or the target don't support tagged queuing, allocate the LUN for * an untagged command. */ if (!should_be_tagged || !setup_use_tagged_queuing || !cmd->device->tagged_supported) { cmd->tag = TAG_NONE; hostdata->busy[cmd->target] |= (1 << cmd->lun); TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged " "command\n", H_NO(cmd), cmd->target, cmd->lun ); } else { TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun]; cmd->tag = find_first_zero_bit( &ta->allocated, MAX_TAGS ); set_bit( cmd->tag, &ta->allocated ); ta->nr_allocated++; TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d " "(now %d tags in use)\n", H_NO(cmd), cmd->tag, cmd->target, cmd->lun, ta->nr_allocated ); } } /* Mark the tag of command 'cmd' as free, or in case of an untagged command, * unlock the LUN. */ static void cmd_free_tag( Scsi_Cmnd *cmd ) { SETUP_HOSTDATA(cmd->host); if (cmd->tag == TAG_NONE) { hostdata->busy[cmd->target] &= ~(1 << cmd->lun); TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n", H_NO(cmd), cmd->target, cmd->lun ); } else if (cmd->tag >= MAX_TAGS) { printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n", H_NO(cmd), cmd->tag ); } else { TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun]; clear_bit( cmd->tag, &ta->allocated ); ta->nr_allocated--; TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n", H_NO(cmd), cmd->tag, cmd->target, cmd->lun ); } } #if 1 static void free_all_tags( void ) { int target, lun; TAG_ALLOC *ta; if (!setup_use_tagged_queuing) return; for( target = 0; target < 8; ++target ) { for( lun = 0; lun < 8; ++lun ) { ta = &TagAlloc[target][lun]; memset( &ta->allocated, 0, MAX_TAGS/8 ); ta->nr_allocated = 0; } } } #endif #endif /* SUPPORT_TAGS */ /* * Function: void merge_consecutive_buffers( Scsi_Cmnd *cmd ) * * Purpose: Try to merge several scatter-gather requests into one DMA * transfer. This is possible if the scatter buffers lie on * physical consecutive addresses. * * Parameters: Scsi_Cmnd *cmd * The command to work on. The first scatter buffer's data are * assumed to be already transfered into ptr/this_residual. */ /* A special issue is when the buffer is exactly at the end of the * last physical memory chunk: VTOP would have to calculate the * physical address just 1 byte behind the end of physical memory. But * it will panic if given this address :-( So we need to avoid calling * VTOP on addresses that don't exist. This is done by keeping * 'endadr' to be the real end address of the buffer, not one byte * more (which would be easier). */ static void merge_consecutive_buffers( Scsi_Cmnd *cmd ) { unsigned long endadr; #if (NDEBUG & NDEBUG_MERGING) unsigned long oldlen = cmd->SCp.this_residual; int cnt = 1; #endif for( endadr = VTOP(cmd->SCp.ptr + cmd->SCp.this_residual - 1); cmd->SCp.buffers_residual && VTOP( (cmd->SCp.buffer+1)->address ) == endadr + 1; ) { MER_PRINTK( "%08lx == %08lx -> merging\n", VTOP( (cmd->SCp.buffer+1)->address ), endadr ); #if (NDEBUG & NDEBUG_MERGING) ++cnt; #endif ++cmd->SCp.buffer; --cmd->SCp.buffers_residual; cmd->SCp.this_residual += cmd->SCp.buffer->length; endadr += cmd->SCp.buffer->length; } #if (NDEBUG & NDEBUG_MERGING) if (oldlen != cmd->SCp.this_residual) MER_PRINTK( "merged %d buffers from %08lx, new length %08lx\n", cnt, (long)(cmd->SCp.ptr), cmd->SCp.this_residual ); #endif } /* * Function : void initialize_SCp(Scsi_Cmnd *cmd) * * Purpose : initialize the saved data pointers for cmd to point to the * start of the buffer. * * Inputs : cmd - Scsi_Cmnd structure to have pointers reset. */ static __inline__ void initialize_SCp(Scsi_Cmnd *cmd) { /* * Initialize the Scsi Pointer field so that all of the commands in the * various queues are valid. */ if (cmd->use_sg) { cmd->SCp.buffer = (struct scatterlist *) cmd->buffer; cmd->SCp.buffers_residual = cmd->use_sg - 1; cmd->SCp.ptr = (char *) cmd->SCp.buffer->address; cmd->SCp.this_residual = cmd->SCp.buffer->length; /* ++roman: Try to merge some scatter-buffers if they are at * consecutive physical addresses. */ merge_consecutive_buffers( cmd ); } else { cmd->SCp.buffer = NULL; cmd->SCp.buffers_residual = 0; cmd->SCp.ptr = (char *) cmd->request_buffer; cmd->SCp.this_residual = cmd->request_bufflen; } } #include <linux/config.h> #include <linux/delay.h> #if NDEBUG static struct { unsigned char mask; const char * name;} signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" }, { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" }, { SR_SEL, "SEL" }, {0, NULL}}, basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}}, icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"}, {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"}, {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"}, {0, NULL}}, mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"}, {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"}, {MR_MONITOR_BSY, "MODE MONITOR BSY"}, {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"}, {0, NULL}}; /* * Function : void NCR5380_print(struct Scsi_Host *instance) * * Purpose : print the SCSI bus signals for debugging purposes * * Input : instance - which NCR5380 */ static void NCR5380_print(struct Scsi_Host *instance) { unsigned char status, data, basr, mr, icr, i; unsigned long flags; save_flags(flags); cli(); data = NCR5380_read(CURRENT_SCSI_DATA_REG); status = NCR5380_read(STATUS_REG); mr = NCR5380_read(MODE_REG); icr = NCR5380_read(INITIATOR_COMMAND_REG); basr = NCR5380_read(BUS_AND_STATUS_REG); restore_flags(flags); printk("STATUS_REG: %02x ", status); for (i = 0; signals[i].mask ; ++i) if (status & signals[i].mask) printk(",%s", signals[i].name); printk("\nBASR: %02x ", basr); for (i = 0; basrs[i].mask ; ++i) if (basr & basrs[i].mask) printk(",%s", basrs[i].name); printk("\nICR: %02x ", icr); for (i = 0; icrs[i].mask; ++i) if (icr & icrs[i].mask) printk(",%s", icrs[i].name); printk("\nMODE: %02x ", mr); for (i = 0; mrs[i].mask; ++i) if (mr & mrs[i].mask) printk(",%s", mrs[i].name); printk("\n"); } static struct { unsigned char value; const char *name; } phases[] = { {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"}, {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"}, {PHASE_UNKNOWN, "UNKNOWN"}}; /* * Function : void NCR5380_print_phase(struct Scsi_Host *instance) * * Purpose : print the current SCSI phase for debugging purposes * * Input : instance - which NCR5380 */ static void NCR5380_print_phase(struct Scsi_Host *instance) { unsigned char status; int i; status = NCR5380_read(STATUS_REG); if (!(status & SR_REQ)) printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO); else { for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i); printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name); } } #else /* !NDEBUG */ /* dummies... */ __inline__ void NCR5380_print(struct Scsi_Host *instance) { }; __inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { }; #endif /* * ++roman: New scheme of calling NCR5380_main() * * If we're not in an interrupt, we can call our main directly, it cannot be * already running. Else, we queue it on a task queue, if not 'main_running' * tells us that a lower level is already executing it. This way, * 'main_running' needs not be protected in a special way. * * queue_main() is a utility function for putting our main onto the task * queue, if main_running is false. It should be called only from a * interrupt or bottom half. */ #include <linux/tqueue.h> #include <linux/interrupt.h> static volatile int main_running = 0; static struct tq_struct NCR5380_tqueue = { NULL, /* next */ 0, /* sync */ (void (*)(void*))NCR5380_main, /* routine, must have (void *) arg... */ NULL /* data */ }; static __inline__ void queue_main(void) { if (!main_running) { /* If in interrupt and NCR5380_main() not already running, queue it on the 'immediate' task queue, to be processed immediately after the current interrupt processing has finished. */ queue_task_irq(&NCR5380_tqueue, &tq_immediate); mark_bh(IMMEDIATE_BH); } /* else: nothing to do: the running NCR5380_main() will pick up any newly queued command. */ } static void NCR5380_all_init (void) { static int done = 0; if (!done) { INI_PRINTK("scsi : NCR5380_all_init()\n"); done = 1; } } /* * Function : void NCR58380_print_options (struct Scsi_Host *instance) * * Purpose : called by probe code indicating the NCR5380 driver * options that were selected. * * Inputs : instance, pointer to this instance. Unused. */ static void NCR5380_print_options (struct Scsi_Host *instance) { printk(" generic options" #ifdef AUTOSENSE " AUTOSENSE" #endif #ifdef REAL_DMA " REAL DMA" #endif #ifdef PARITY " PARITY" #endif #ifdef SUPPORT_TAGS " SCSI-2 TAGGED QUEUING" #endif ); printk(" generic release=%d", NCR5380_PUBLIC_RELEASE); } /* * Function : void NCR5380_print_status (struct Scsi_Host *instance) * * Purpose : print commands in the various queues, called from * NCR5380_abort and NCR5380_debug to aid debugging. * * Inputs : instance, pointer to this instance. */ static void NCR5380_print_status (struct Scsi_Host *instance) { char pr_bfr[256]; char *start; int len; NCR_PRINT(NDEBUG_ANY); NCR_PRINT_PHASE(NDEBUG_ANY); len = NCR5380_proc_info(pr_bfr, &start, 0, sizeof(pr_bfr), HOSTNO, 0); pr_bfr[len] = 0; printk("\n%s\n", pr_bfr); } /******************************************/ /* * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED] * * *buffer: I/O buffer * **start: if inout == FALSE pointer into buffer where user read should start * offset: current offset * length: length of buffer * hostno: Scsi_Host host_no * inout: TRUE - user is writing; FALSE - user is reading * * Return the number of bytes read from or written */ #undef SPRINTF #define SPRINTF(args...) do { if(pos < buffer + length) pos += sprintf(pos, ## args); } while(0) static char *lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length); static char *lprint_command (unsigned char *cmd, char *pos, char *buffer, int len); static char *lprint_opcode(int opcode, char *pos, char *buffer, int length); #ifndef NCR5380_proc_info static #endif int NCR5380_proc_info (char *buffer, char **start, off_t offset, int length, int hostno, int inout) { char *pos = buffer; struct Scsi_Host *instance; struct NCR5380_hostdata *hostdata; Scsi_Cmnd *ptr; unsigned long flags; for (instance = first_instance; instance && HOSTNO != hostno; instance = instance->next) ; if (!instance) return(-ESRCH); hostdata = (struct NCR5380_hostdata *)instance->hostdata; if (inout) { /* Has data been written to the file ? */ return(-ENOSYS); /* Currently this is a no-op */ } SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE); save_flags(flags); cli(); SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't"); if (!hostdata->connected) SPRINTF("scsi%d: no currently connected command\n", HOSTNO); else pos = lprint_Scsi_Cmnd ((Scsi_Cmnd *) hostdata->connected, pos, buffer, length); SPRINTF("scsi%d: issue_queue\n", HOSTNO); for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr)) pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length); SPRINTF("scsi%d: disconnected_queue\n", HOSTNO); for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = NEXT(ptr)) pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length); restore_flags(flags); *start = buffer; if (pos - buffer < offset) return 0; else if (pos - buffer - offset < length) return pos - buffer - offset; return length; } static char * lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length) { SPRINTF("scsi%d: destination target %d, lun %d\n", H_NO(cmd), cmd->target, cmd->lun); SPRINTF(" command = "); pos = lprint_command (cmd->cmnd, pos, buffer, length); return (pos); } static char * lprint_command (unsigned char *command, char *pos, char *buffer, int length) { int i, s; pos = lprint_opcode(command[0], pos, buffer, length); for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) SPRINTF("%02x ", command[i]); SPRINTF("\n"); return(pos); } static char *lprint_opcode(int opcode, char *pos, char *buffer, int length) { SPRINTF("%2d (0x%02x)", opcode, opcode); return(pos); } /* * Function : void NCR5380_init (struct Scsi_Host *instance) * * Purpose : initializes *instance and corresponding 5380 chip. * * Inputs : instance - instantiation of the 5380 driver. * * Notes : I assume that the host, hostno, and id bits have been * set correctly. I don't care about the irq and other fields. * */ static void NCR5380_init (struct Scsi_Host *instance, int flags) { int i; SETUP_HOSTDATA(instance); NCR5380_all_init(); hostdata->aborted = 0; hostdata->id_mask = 1 << instance->this_id; hostdata->id_higher_mask = 0; for (i = hostdata->id_mask; i <= 0x80; i <<= 1) if (i > hostdata->id_mask) hostdata->id_higher_mask |= i; for (i = 0; i < 8; ++i) hostdata->busy[i] = 0; #ifdef SUPPORT_TAGS init_tags(); #endif #if defined (REAL_DMA) hostdata->dma_len = 0; #endif hostdata->targets_present = 0; hostdata->connected = NULL; hostdata->issue_queue = NULL; hostdata->disconnected_queue = NULL; hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT; if (!the_template) { the_template = instance->hostt; first_instance = instance; } #ifndef AUTOSENSE if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)) printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n" " without AUTOSENSE option, contingent allegiance conditions may\n" " be incorrectly cleared.\n", HOSTNO); #endif /* def AUTOSENSE */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); NCR5380_write(MODE_REG, MR_BASE); NCR5380_write(TARGET_COMMAND_REG, 0); NCR5380_write(SELECT_ENABLE_REG, 0); } /* * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd, * void (*done)(Scsi_Cmnd *)) * * Purpose : enqueues a SCSI command * * Inputs : cmd - SCSI command, done - function called on completion, with * a pointer to the command descriptor. * * Returns : 0 * * Side effects : * cmd is added to the per instance issue_queue, with minor * twiddling done to the host specific fields of cmd. If the * main coroutine is not running, it is restarted. * */ /* Only make static if a wrapper function is used */ #ifndef NCR5380_queue_command static #endif int NCR5380_queue_command (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *)) { SETUP_HOSTDATA(cmd->host); Scsi_Cmnd *tmp; int oldto; unsigned long flags; extern int scsi_update_timeout(Scsi_Cmnd * SCset, int timeout); #if (NDEBUG & NDEBUG_NO_WRITE) switch (cmd->cmnd[0]) { case WRITE_6: case WRITE_10: printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n", H_NO(cmd)); cmd->result = (DID_ERROR << 16); done(cmd); return 0; } #endif /* (NDEBUG & NDEBUG_NO_WRITE) */ #ifdef NCR5380_STATS # if 0 if (!hostdata->connected && !hostdata->issue_queue && !hostdata->disconnected_queue) { hostdata->timebase = jiffies; } # endif # ifdef NCR5380_STAT_LIMIT if (cmd->request_bufflen > NCR5380_STAT_LIMIT) # endif switch (cmd->cmnd[0]) { case WRITE: case WRITE_6: case WRITE_10: hostdata->time_write[cmd->target] -= (jiffies - hostdata->timebase); hostdata->bytes_write[cmd->target] += cmd->request_bufflen; hostdata->pendingw++; break; case READ: case READ_6: case READ_10: hostdata->time_read[cmd->target] -= (jiffies - hostdata->timebase); hostdata->bytes_read[cmd->target] += cmd->request_bufflen; hostdata->pendingr++; break; } #endif /* * We use the host_scribble field as a pointer to the next command * in a queue */ NEXT(cmd) = NULL; cmd->scsi_done = done; cmd->result = 0; /* * Insert the cmd into the issue queue. Note that REQUEST SENSE * commands are added to the head of the queue since any command will * clear the contingent allegiance condition that exists and the * sense data is only guaranteed to be valid while the condition exists. */ save_flags(flags); cli(); /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA. * Otherwise a running NCR5380_main may steal the lock. * Lock before actually inserting due to fairness reasons explained in * atari_scsi.c. If we insert first, then it's impossible for this driver * to release the lock. * Stop timer for this command while waiting for the lock, or timeouts * may happen (and they really do), and it's no good if the command doesn't * appear in any of the queues. * ++roman: Just disabling the NCR interrupt isn't sufficient here, * because also a timer int can trigger an abort or reset, which would * alter queues and touch the lock. */ if (!IS_A_TT()) { oldto = scsi_update_timeout(cmd, 0); falcon_get_lock(); scsi_update_timeout(cmd, oldto); } if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { LIST(cmd, hostdata->issue_queue); NEXT(cmd) = hostdata->issue_queue; hostdata->issue_queue = cmd; } else { for (tmp = (Scsi_Cmnd *)hostdata->issue_queue; NEXT(tmp); tmp = NEXT(tmp)) ; LIST(cmd, tmp); NEXT(tmp) = cmd; } restore_flags(flags); QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd), (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); /* If queue_command() is called from an interrupt (real one or bottom * half), we let queue_main() do the job of taking care about main. If it * is already running, this is a no-op, else main will be queued. * * If we're not in an interrupt, we can call NCR5380_main() * unconditionally, because it cannot be already running. */ if (intr_count > 0) queue_main(); else NCR5380_main(); return 0; } /* * Function : NCR5380_main (void) * * Purpose : NCR5380_main is a coroutine that runs as long as more work can * be done on the NCR5380 host adapters in a system. Both * NCR5380_queue_command() and NCR5380_intr() will try to start it * in case it is not running. * * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should * reenable them. This prevents reentrancy and kernel stack overflow. */ static void NCR5380_main (void) { Scsi_Cmnd *tmp, *prev; struct Scsi_Host *instance = first_instance; struct NCR5380_hostdata *hostdata = HOSTDATA(instance); int done; unsigned long flags; /* * We run (with interrupts disabled) until we're sure that none of * the host adapters have anything that can be done, at which point * we set main_running to 0 and exit. * * Interrupts are enabled before doing various other internal * instructions, after we've decided that we need to run through * the loop again. * * this should prevent any race conditions. * * ++roman: Just disabling the NCR interrupt isn't sufficient here, * because also a timer int can trigger an abort or reset, which can * alter queues and touch the Falcon lock. */ /* Tell int handlers main() is now already executing. Note that no races are possible here. If an int comes in before 'main_running' is set here, and queues/executes main via the task queue, it doesn't do any harm, just this instance of main won't find any work left to do. */ main_running = 1; save_flags(flags); do { cli(); /* Freeze request queues */ done = 1; if (!hostdata->connected) { MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO ); /* * Search through the issue_queue for a command destined * for a target that's not busy. */ #if (NDEBUG & NDEBUG_LISTS) for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp)) ; /*printk("%p ", tmp);*/ if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/ #endif for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) { #if (NDEBUG & NDEBUG_LISTS) if (prev != tmp) printk("MAIN tmp=%p target=%d busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun); #endif /* When we find one, remove it from the issue queue. */ /* ++guenther: possible race with Falcon locking */ if ( #ifdef SUPPORT_TAGS !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE) #else !(hostdata->busy[tmp->target] & (1 << tmp->lun)) #endif ) { cli(); /* ++guenther: just to be sure, this must be atomic */ if (prev) { REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); NEXT(prev) = NEXT(tmp); } else { REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp)); hostdata->issue_queue = NEXT(tmp); } NEXT(tmp) = NULL; falcon_dont_release++; /* reenable interrupts after finding one */ restore_flags(flags); /* * Attempt to establish an I_T_L nexus here. * On success, instance->hostdata->connected is set. * On failure, we must add the command back to the * issue queue so we can keep trying. */ DPRINTK(NDEBUG_MAIN | NDEBUG_QUEUES, "scsi%d: main(): command for target %d lun %d " "removed from issue_queue\n", HOSTNO, tmp->target, tmp->lun); /* * REQUEST SENSE commands are issued without tagged * queueing, even on SCSI-II devices because the * contingent allegiance condition exists for the * entire unit. */ /* ++roman: ...and the standard also requires that * REQUEST SENSE command are untagged. */ #ifdef SUPPORT_TAGS cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE ); #endif if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) { falcon_dont_release--; /* release if target did not response! */ falcon_release_lock_if_possible( hostdata ); break; } else { cli(); LIST(tmp, hostdata->issue_queue); NEXT(tmp) = hostdata->issue_queue; hostdata->issue_queue = tmp; #ifdef SUPPORT_TAGS cmd_free_tag( tmp ); #endif falcon_dont_release--; restore_flags(flags); DPRINTK(NDEBUG_MAIN | NDEBUG_QUEUES, "scsi%d: main(): select() failed, " "returned to issue_queue\n", HOSTNO); if (hostdata->connected) break; } } /* if target/lun/target queue is not busy */ } /* for issue_queue */ } /* if (!hostdata->connected) */ if (hostdata->connected #ifdef REAL_DMA && !hostdata->dma_len #endif ) { restore_flags(flags); MAIN_PRINTK("scsi%d: main: performing information transfer\n", HOSTNO); NCR5380_information_transfer(instance); MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO); done = 0; } } while (!done); /* Better allow ints _after_ 'main_running' has been cleared, else an interrupt could believe we'll pick up the work it left for us, but we won't see it anymore here... */ main_running = 0; restore_flags(flags); } #ifdef REAL_DMA /* * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) * * Purpose : Called by interrupt handler when DMA finishes or a phase * mismatch occurs (which would finish the DMA transfer). * * Inputs : instance - this instance of the NCR5380. * */ static void NCR5380_dma_complete( struct Scsi_Host *instance ) { SETUP_HOSTDATA(instance); int transfered, saved_data = 0, overrun = 0, cnt, toPIO; unsigned char **data, p; volatile int *count; if (!hostdata->connected) { printk(KERN_WARNING "scsi%d: received end of DMA interrupt with " "no connected cmd\n", HOSTNO); return; } if (atari_read_overruns) { p = hostdata->connected->SCp.phase; if (p & SR_IO) { udelay(10); if ((((NCR5380_read(BUS_AND_STATUS_REG)) & (BASR_PHASE_MATCH|BASR_ACK)) == (BASR_PHASE_MATCH|BASR_ACK))) { saved_data = NCR5380_read(INPUT_DATA_REG); overrun = 1; DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO); } } } DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n", HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)); (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); NCR5380_write(MODE_REG, MR_BASE); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); transfered = hostdata->dma_len - NCR5380_dma_residual(instance); hostdata->dma_len = 0; data = (unsigned char **) &(hostdata->connected->SCp.ptr); count = &(hostdata->connected->SCp.this_residual); *data += transfered; *count -= transfered; if (atari_read_overruns) { if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) { cnt = toPIO = atari_read_overruns; if (overrun) { DMA_PRINTK("Got an input overrun, using saved byte\n"); *(*data)++ = saved_data; (*count)--; cnt--; toPIO--; } DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data); NCR5380_transfer_pio(instance, &p, &cnt, data); *count -= toPIO - cnt; } } } #endif /* REAL_DMA */ /* * Function : void NCR5380_intr (int irq) * * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses * from the disconnected queue, and restarting NCR5380_main() * as required. * * Inputs : int irq, irq that caused this interrupt. * */ static void NCR5380_intr (int irq, void *dev_id, struct pt_regs *regs) { struct Scsi_Host *instance = first_instance; int done = 1; unsigned char basr; INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO); /* Look for pending interrupts */ basr = NCR5380_read(BUS_AND_STATUS_REG); INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr); /* dispatch to appropriate routine if found and done=0 */ if (basr & BASR_IRQ) { NCR_PRINT(NDEBUG_INTR); if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) { done = 0; ENABLE_IRQ(); INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO); NCR5380_reselect(instance); (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); } else if (basr & BASR_PARITY_ERROR) { INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO); (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO); (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); } else { /* * The rest of the interrupt conditions can occur only during a * DMA transfer */ #if defined(REAL_DMA) /* * We should only get PHASE MISMATCH and EOP interrupts if we have * DMA enabled, so do a sanity check based on the current setting * of the MODE register. */ if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) { INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO); NCR5380_dma_complete( instance ); done = 0; ENABLE_IRQ(); } else #endif /* REAL_DMA */ { /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */ if (basr & BASR_PHASE_MATCH) printk(KERN_NOTICE "scsi%d: unknown interrupt, " "BASR 0x%x, MR 0x%x, SR 0x%x\n", HOSTNO, basr, NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); } } /* if !(SELECTION || PARITY) */ } /* BASR & IRQ */ else { printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, " "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr, NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); } if (!done) { INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO); /* Put a call to NCR5380_main() on the queue... */ queue_main(); } } #ifdef NCR5380_STATS static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd* cmd) { # ifdef NCR5380_STAT_LIMIT if (cmd->request_bufflen > NCR5380_STAT_LIMIT) # endif switch (cmd->cmnd[0]) { case WRITE: case WRITE_6: case WRITE_10: hostdata->time_write[cmd->target] += (jiffies - hostdata->timebase); /*hostdata->bytes_write[cmd->target] += cmd->request_bufflen;*/ hostdata->pendingw--; break; case READ: case READ_6: case READ_10: hostdata->time_read[cmd->target] += (jiffies - hostdata->timebase); /*hostdata->bytes_read[cmd->target] += cmd->request_bufflen;*/ hostdata->pendingr--; break; } } #endif /* * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, * int tag); * * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, * including ARBITRATION, SELECTION, and initial message out for * IDENTIFY and queue messages. * * Inputs : instance - instantiation of the 5380 driver on which this * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for * the command that is presently connected. * * Returns : -1 if selection could not execute for some reason, * 0 if selection succeeded or failed because the target * did not respond. * * Side effects : * If bus busy, arbitration failed, etc, NCR5380_select() will exit * with registers as they should have been on entry - ie * SELECT_ENABLE will be set appropriately, the NCR5380 * will cease to drive any SCSI bus signals. * * If successful : I_T_L or I_T_L_Q nexus will be established, * instance->connected will be set to cmd. * SELECT interrupt will be disabled. * * If failed (no target) : cmd->scsi_done() will be called, and the * cmd->result host byte set to DID_BAD_TARGET. */ static int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag) { SETUP_HOSTDATA(instance); unsigned char tmp[3], phase; unsigned char *data; int len; unsigned long timeout; unsigned long flags; hostdata->restart_select = 0; NCR_PRINT(NDEBUG_ARBITRATION); ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO, instance->this_id); /* * Set the phase bits to 0, otherwise the NCR5380 won't drive the * data bus during SELECTION. */ save_flags(flags); cli(); if (hostdata->connected) { restore_flags(flags); return -1; } NCR5380_write(TARGET_COMMAND_REG, 0); /* * Start arbitration. */ NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); NCR5380_write(MODE_REG, MR_ARBITRATE); restore_flags(flags); /* Wait for arbitration logic to complete */ #if NCR_TIMEOUT { unsigned long timeout = jiffies + 2*NCR_TIMEOUT; while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && jiffies < timeout && !hostdata->connected) ; if (jiffies >= timeout) { printk("scsi : arbitration timeout at %d\n", __LINE__); NCR5380_write(MODE_REG, MR_BASE); NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); return -1; } } #else /* NCR_TIMEOUT */ while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) && !hostdata->connected); #endif ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO); if (hostdata->connected) { NCR5380_write(MODE_REG, MR_BASE); return -1; } /* * The arbitration delay is 2.2us, but this is a minimum and there is * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate * the integral nature of udelay(). * */ udelay(3); /* Check for lost arbitration */ if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || hostdata->connected) { NCR5380_write(MODE_REG, MR_BASE); ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n", HOSTNO); return -1; } /* after/during arbitration, BSY should be asserted. IBM DPES-31080 Version S31Q works now */ /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY ) ; if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || hostdata->connected) { NCR5380_write(MODE_REG, MR_BASE); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n", HOSTNO); return -1; } /* * Again, bus clear + bus settle time is 1.2us, however, this is * a minimum so we'll udelay ceil(1.2) */ #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY /* ++roman: But some targets (see above :-) seem to need a bit more... */ udelay(15); #else udelay(2); #endif if (hostdata->connected) { NCR5380_write(MODE_REG, MR_BASE); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); return -1; } ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO); /* * Now that we have won arbitration, start Selection process, asserting * the host and target ID's on the SCSI bus. */ NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->target))); /* * Raise ATN while SEL is true before BSY goes false from arbitration, * since this is the only way to guarantee that we'll get a MESSAGE OUT * phase immediately after selection. */ NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL )); NCR5380_write(MODE_REG, MR_BASE); /* * Reselect interrupts must be turned off prior to the dropping of BSY, * otherwise we will trigger an interrupt. */ if (hostdata->connected) { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); return -1; } NCR5380_write(SELECT_ENABLE_REG, 0); /* * The initiator shall then wait at least two deskew delays and release * the BSY signal. */ udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ /* Reset BSY */ NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL)); /* * Something weird happens when we cease to drive BSY - looks * like the board/chip is letting us do another read before the * appropriate propagation delay has expired, and we're confusing * a BSY signal from ourselves as the target's response to SELECTION. * * A small delay (the 'C++' frontend breaks the pipeline with an * unnecessary jump, making it work on my 386-33/Trantor T128, the * tighter 'C' code breaks and requires this) solves the problem - * the 1 us delay is arbitrary, and only used because this delay will * be the same on other platforms and since it works here, it should * work there. * * wingel suggests that this could be due to failing to wait * one deskew delay. */ udelay(1); SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->target); /* * The SCSI specification calls for a 250 ms timeout for the actual * selection. */ timeout = jiffies + 25; /* * XXX very interesting - we're seeing a bounce where the BSY we * asserted is being reflected / still asserted (propagation delay?) * and it's detecting as true. Sigh. */ #if 0 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert * IO while SEL is true. But again, there are some disks out the in the * world that do that nevertheless. (Somebody claimed that this announces * reselection capability of the target.) So we better skip that test and * only wait for BSY... (Famous german words: Der Klügere gibt nach :-) */ while ((jiffies < timeout) && !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO))); if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); NCR5380_reselect(instance); printk (KERN_ERR "scsi%d: reselection after won arbitration?\n", HOSTNO); NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); return -1; } #else while ((jiffies < timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY)); #endif /* * No less than two deskew delays after the initiator detects the * BSY signal is true, it shall release the SEL signal and may * change the DATA BUS. -wingel */ udelay(1); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); if (hostdata->targets_present & (1 << cmd->target)) { printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO); if (hostdata->restart_select) printk(KERN_NOTICE "\trestart select\n"); NCR_PRINT(NDEBUG_ANY); NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); return -1; } cmd->result = DID_BAD_TARGET << 16; #ifdef NCR5380_STATS collect_stats(hostdata, cmd); #endif #ifdef SUPPORT_TAGS cmd_free_tag( cmd ); #endif cmd->scsi_done(cmd); NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO); NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); return 0; } hostdata->targets_present |= (1 << cmd->target); /* * Since we followed the SCSI spec, and raised ATN while SEL * was true but before BSY was false during selection, the information * transfer phase should be a MESSAGE OUT phase so that we can send the * IDENTIFY message. * * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG * message (2 bytes) with a tag ID that we increment with every command * until it wraps back to 0. * * XXX - it turns out that there are some broken SCSI-II devices, * which claim to support tagged queuing but fail when more than * some number of commands are issued at once. */ /* Wait for start of REQ/ACK handshake */ while (!(NCR5380_read(STATUS_REG) & SR_REQ)); SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n", HOSTNO, cmd->target); tmp[0] = IDENTIFY(1, cmd->lun); #ifdef SUPPORT_TAGS if (cmd->tag != TAG_NONE) { tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG; tmp[2] = cmd->tag; len = 3; } else len = 1; #else len = 1; cmd->tag=0; #endif /* SUPPORT_TAGS */ /* Send message(s) */ data = tmp; phase = PHASE_MSGOUT; NCR5380_transfer_pio(instance, &phase, &len, &data); SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO); /* XXX need to handle errors here */ hostdata->connected = cmd; #ifndef SUPPORT_TAGS hostdata->busy[cmd->target] |= (1 << cmd->lun); #endif initialize_SCp(cmd); return 0; } /* * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, * unsigned char *phase, int *count, unsigned char **data) * * Purpose : transfers data in given phase using polled I/O * * Inputs : instance - instance of driver, *phase - pointer to * what phase is expected, *count - pointer to number of * bytes to transfer, **data - pointer to data pointer. * * Returns : -1 when different phase is entered without transferring * maximum number of bytes, 0 if all bytes are transfered or exit * is in same phase. * * Also, *phase, *count, *data are modified in place. * * XXX Note : handling for bus free may be useful. */ /* * Note : this code is not as quick as it could be, however it * IS 100% reliable, and for the actual data transfer where speed * counts, we will always do a pseudo DMA or DMA transfer. */ static int NCR5380_transfer_pio( struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) { register unsigned char p = *phase, tmp; register int c = *count; register unsigned char *d = *data; /* * The NCR5380 chip will only drive the SCSI bus when the * phase specified in the appropriate bits of the TARGET COMMAND * REGISTER match the STATUS REGISTER */ NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); do { /* * Wait for assertion of REQ, after which the phase bits will be * valid */ while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)); HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO); /* Check for phase mismatch */ if ((tmp & PHASE_MASK) != p) { PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO); NCR_PRINT_PHASE(NDEBUG_PIO); break; } /* Do actual transfer from SCSI bus to / from memory */ if (!(p & SR_IO)) NCR5380_write(OUTPUT_DATA_REG, *d); else *d = NCR5380_read(CURRENT_SCSI_DATA_REG); ++d; /* * The SCSI standard suggests that in MSGOUT phase, the initiator * should drop ATN on the last byte of the message phase * after REQ has been asserted for the handshake but before * the initiator raises ACK. */ if (!(p & SR_IO)) { if (!((p & SR_MSG) && c > 1)) { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); NCR_PRINT(NDEBUG_PIO); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK); } else { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN); NCR_PRINT(NDEBUG_PIO); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); } } else { NCR_PRINT(NDEBUG_PIO); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); } while (NCR5380_read(STATUS_REG) & SR_REQ); HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO); /* * We have several special cases to consider during REQ/ACK handshaking : * 1. We were in MSGOUT phase, and we are on the last byte of the * message. ATN must be dropped as ACK is dropped. * * 2. We are in a MSGIN phase, and we are on the last byte of the * message. We must exit with ACK asserted, so that the calling * code may raise ATN before dropping ACK to reject the message. * * 3. ACK and ATN are clear and the target may proceed as normal. */ if (!(p == PHASE_MSGIN && c == 1)) { if (p == PHASE_MSGOUT && c > 1) NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); else NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); } } while (--c); PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c); *count = c; *data = d; tmp = NCR5380_read(STATUS_REG); /* The phase read from the bus is valid if either REQ is (already) * asserted or if ACK hasn't been released yet. The latter is the case if * we're in MSGIN and all wanted bytes have been received. */ if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0)) *phase = tmp & PHASE_MASK; else *phase = PHASE_UNKNOWN; if (!c || (*phase == p)) return 0; else return -1; } /* * Function : do_abort (Scsi_Host *host) * * Purpose : abort the currently established nexus. Should only be * called from a routine which can drop into a * * Returns : 0 on success, -1 on failure. */ static int do_abort (struct Scsi_Host *host) { unsigned char tmp, *msgptr, phase; int len; /* Request message out phase */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); /* * Wait for the target to indicate a valid phase by asserting * REQ. Once this happens, we'll have either a MSGOUT phase * and can immediately send the ABORT message, or we'll have some * other phase and will have to source/sink data. * * We really don't care what value was on the bus or what value * the target sees, so we just handshake. */ while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ); NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); while (NCR5380_read(STATUS_REG) & SR_REQ); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); } tmp = ABORT; msgptr = &tmp; len = 1; phase = PHASE_MSGOUT; NCR5380_transfer_pio (host, &phase, &len, &msgptr); /* * If we got here, and the command completed successfully, * we're about to go into bus free state. */ return len ? -1 : 0; } #if defined(REAL_DMA) /* * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, * unsigned char *phase, int *count, unsigned char **data) * * Purpose : transfers data in given phase using either real * or pseudo DMA. * * Inputs : instance - instance of driver, *phase - pointer to * what phase is expected, *count - pointer to number of * bytes to transfer, **data - pointer to data pointer. * * Returns : -1 when different phase is entered without transferring * maximum number of bytes, 0 if all bytes or transfered or exit * is in same phase. * * Also, *phase, *count, *data are modified in place. * */ static int NCR5380_transfer_dma( struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) { SETUP_HOSTDATA(instance); register int c = *count; register unsigned char p = *phase; register unsigned char *d = *data; unsigned char tmp; unsigned long flags; if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { *phase = tmp; return -1; } if (atari_read_overruns && (p & SR_IO)) { c -= atari_read_overruns; } DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n", HOSTNO, (p & SR_IO) ? "reading" : "writing", c, (p & SR_IO) ? "to" : "from", d); NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); #ifdef REAL_DMA NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); #endif /* def REAL_DMA */ if (IS_A_TT()) { /* On the Medusa, it is a must to initialize the DMA before * starting the NCR. This is also the cleaner way for the TT. */ save_flags(flags); cli(); hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c); restore_flags(flags); } if (p & SR_IO) NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); else { NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); NCR5380_write(START_DMA_SEND_REG, 0); } if (!IS_A_TT()) { /* On the Falcon, the DMA setup must be done after the last */ /* NCR access, else the DMA setup gets trashed! */ save_flags(flags); cli(); hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c); restore_flags(flags); } return 0; } #endif /* defined(REAL_DMA) */ /* * Function : NCR5380_information_transfer (struct Scsi_Host *instance) * * Purpose : run through the various SCSI phases and do as the target * directs us to. Operates on the currently connected command, * instance->connected. * * Inputs : instance, instance for which we are doing commands * * Side effects : SCSI things happen, the disconnected queue will be * modified if a command disconnects, *instance->connected will * change. * * XXX Note : we need to watch for bus free or a reset condition here * to recover from an unexpected bus free condition. */ static void NCR5380_information_transfer (struct Scsi_Host *instance) { SETUP_HOSTDATA(instance); unsigned long flags; unsigned char msgout = NOP; int sink = 0; int len; #if defined(REAL_DMA) int transfersize; #endif unsigned char *data; unsigned char phase, tmp, extended_msg[10], old_phase=0xff; Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected; while (1) { tmp = NCR5380_read(STATUS_REG); /* We only have a valid SCSI phase when REQ is asserted */ if (tmp & SR_REQ) { phase = (tmp & PHASE_MASK); if (phase != old_phase) { old_phase = phase; NCR_PRINT_PHASE(NDEBUG_INFORMATION); } if (sink && (phase != PHASE_MSGOUT)) { NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); while (NCR5380_read(STATUS_REG) & SR_REQ); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); sink = 0; continue; } switch (phase) { case PHASE_DATAOUT: #if (NDEBUG & NDEBUG_NO_DATAOUT) printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT " "aborted\n", HOSTNO); sink = 1; do_abort(instance); cmd->result = DID_ERROR << 16; cmd->done(cmd); return; #endif case PHASE_DATAIN: /* * If there is no room left in the current buffer in the * scatter-gather list, move onto the next one. */ if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { ++cmd->SCp.buffer; --cmd->SCp.buffers_residual; cmd->SCp.this_residual = cmd->SCp.buffer->length; cmd->SCp.ptr = cmd->SCp.buffer->address; /* ++roman: Try to merge some scatter-buffers if * they are at consecutive physical addresses. */ merge_consecutive_buffers( cmd ); INF_PRINTK("scsi%d: %d bytes and %d buffers left\n", HOSTNO, cmd->SCp.this_residual, cmd->SCp.buffers_residual); } /* * The preferred transfer method is going to be * PSEUDO-DMA for systems that are strictly PIO, * since we can let the hardware do the handshaking. * * For this to work, we need to know the transfersize * ahead of time, since the pseudo-DMA code will sit * in an unconditional loop. */ /* ++roman: I suggest, this should be * #if def(REAL_DMA) * instead of leaving REAL_DMA out. */ #if defined(REAL_DMA) if (!cmd->device->borken && (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) { len = transfersize; cmd->SCp.phase = phase; if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) { /* * If the watchdog timer fires, all future * accesses to this device will use the * polled-IO. */ printk(KERN_NOTICE "scsi%d: switching target %d " "lun %d to slow handshake\n", HOSTNO, cmd->target, cmd->lun); cmd->device->borken = 1; NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); sink = 1; do_abort(instance); cmd->result = DID_ERROR << 16; cmd->done(cmd); /* XXX - need to source or sink data here, as appropriate */ } else { #ifdef REAL_DMA /* ++roman: When using real DMA, * information_transfer() should return after * starting DMA since it has nothing more to * do. */ return; #else cmd->SCp.this_residual -= transfersize - len; #endif } } else #endif /* defined(REAL_DMA) */ NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **) &cmd->SCp.ptr); break; case PHASE_MSGIN: len = 1; data = &tmp; NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */ NCR5380_transfer_pio(instance, &phase, &len, &data); cmd->SCp.Message = tmp; switch (tmp) { /* * Linking lets us reduce the time required to get the * next command out to the device, hopefully this will * mean we don't waste another revolution due to the delays * required by ARBITRATION and another SELECTION. * * In the current implementation proposal, low level drivers * merely have to start the next command, pointed to by * next_link, done() is called as with unlinked commands. */ #ifdef LINKED case LINKED_CMD_COMPLETE: case LINKED_FLG_CMD_COMPLETE: /* Accept message by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); LNK_PRINTK("scsi%d: target %d lun %d linked command " "complete.\n", HOSTNO, cmd->target, cmd->lun); /* Enable reselect interrupts */ NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); /* * Sanity check : A linked command should only terminate * with one of these messages if there are more linked * commands available. */ if (!cmd->next_link) { printk(KERN_NOTICE "scsi%d: target %d lun %d " "linked command complete, no next_link\n", HOSTNO, cmd->target, cmd->lun); sink = 1; do_abort (instance); return; } initialize_SCp(cmd->next_link); /* The next command is still part of this process; copy it * and don't free it! */ cmd->next_link->tag = cmd->tag; cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); LNK_PRINTK("scsi%d: target %d lun %d linked request " "done, calling scsi_done().\n", HOSTNO, cmd->target, cmd->lun); #ifdef NCR5380_STATS collect_stats(hostdata, cmd); #endif cmd->scsi_done(cmd); cmd = hostdata->connected; break; #endif /* def LINKED */ case ABORT: case COMMAND_COMPLETE: /* Accept message by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); /* ++guenther: possible race with Falcon locking */ falcon_dont_release++; hostdata->connected = NULL; QU_PRINTK("scsi%d: command for target %d, lun %d " "completed\n", HOSTNO, cmd->target, cmd->lun); #ifdef SUPPORT_TAGS cmd_free_tag( cmd ); if (cmd->SCp.Status == QUEUE_FULL) { /* Turn a QUEUE FULL status into BUSY, I think the * mid level cannot handle QUEUE FULL :-( (The * command is retried after BUSY). Also update our * queue size to the number of currently issued * commands now. */ TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun]; TAG_PRINTK("scsi%d: target %d lun %d returned " "QUEUE_FULL after %d commands\n", HOSTNO, cmd->target, cmd->lun, ta->nr_allocated); if (ta->queue_size > ta->nr_allocated) ta->nr_allocated = ta->queue_size; cmd->SCp.Status = BUSY; } #else hostdata->busy[cmd->target] &= ~(1 << cmd->lun); #endif /* Enable reselect interrupts */ NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); /* * I'm not sure what the correct thing to do here is : * * If the command that just executed is NOT a request * sense, the obvious thing to do is to set the result * code to the values of the stored parameters. * * If it was a REQUEST SENSE command, we need some way to * differentiate between the failure code of the original * and the failure code of the REQUEST sense - the obvious * case is success, where we fall through and leave the * result code unchanged. * * The non-obvious place is where the REQUEST SENSE failed */ if (cmd->cmnd[0] != REQUEST_SENSE) cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); else if (cmd->SCp.Status != GOOD) cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); #ifdef AUTOSENSE if ((cmd->cmnd[0] != REQUEST_SENSE) && (cmd->SCp.Status == CHECK_CONDITION)) { ASEN_PRINTK("scsi%d: performing request sense\n", HOSTNO); cmd->cmnd[0] = REQUEST_SENSE; cmd->cmnd[1] &= 0xe0; cmd->cmnd[2] = 0; cmd->cmnd[3] = 0; cmd->cmnd[4] = sizeof(cmd->sense_buffer); cmd->cmnd[5] = 0; cmd->SCp.buffer = NULL; cmd->SCp.buffers_residual = 0; cmd->SCp.ptr = (char *) cmd->sense_buffer; cmd->SCp.this_residual = sizeof(cmd->sense_buffer); save_flags(flags); cli(); LIST(cmd,hostdata->issue_queue); NEXT(cmd) = hostdata->issue_queue; hostdata->issue_queue = (Scsi_Cmnd *) cmd; restore_flags(flags); QU_PRINTK("scsi%d: REQUEST SENSE added to head of " "issue queue\n", H_NO(cmd)); } else #endif /* def AUTOSENSE */ { #ifdef NCR5380_STATS collect_stats(hostdata, cmd); #endif cmd->scsi_done(cmd); } NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); /* * Restore phase bits to 0 so an interrupted selection, * arbitration can resume. */ NCR5380_write(TARGET_COMMAND_REG, 0); while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) barrier(); falcon_dont_release--; /* ++roman: For Falcon SCSI, release the lock on the * ST-DMA here if no other commands are waiting on the * disconnected queue. */ falcon_release_lock_if_possible( hostdata ); return; case MESSAGE_REJECT: /* Accept message by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); /* Enable reselect interrupts */ NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); switch (hostdata->last_message) { case HEAD_OF_QUEUE_TAG: case ORDERED_QUEUE_TAG: case SIMPLE_QUEUE_TAG: /* The target obviously doesn't support tagged * queuing, even though it announced this ability in * its INQUIRY data ?!? (maybe only this LUN?) Ok, * clear 'tagged_supported' and lock the LUN, since * the command is treated as untagged further on. */ cmd->device->tagged_supported = 0; hostdata->busy[cmd->target] |= (1 << cmd->lun); cmd->tag = TAG_NONE; TAG_PRINTK("scsi%d: target %d lun %d rejected " "QUEUE_TAG message; tagged queuing " "disabled\n", HOSTNO, cmd->target, cmd->lun); break; } break; case DISCONNECT: /* Accept message by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); save_flags(flags); cli(); cmd->device->disconnect = 1; LIST(cmd,hostdata->disconnected_queue); NEXT(cmd) = hostdata->disconnected_queue; hostdata->connected = NULL; hostdata->disconnected_queue = cmd; restore_flags(flags); QU_PRINTK("scsi%d: command for target %d lun %d was " "moved from connected to the " "disconnected_queue\n", HOSTNO, cmd->target, cmd->lun); /* * Restore phase bits to 0 so an interrupted selection, * arbitration can resume. */ NCR5380_write(TARGET_COMMAND_REG, 0); /* Enable reselect interrupts */ NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); /* Wait for bus free to avoid nasty timeouts */ while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) barrier(); return; /* * The SCSI data pointer is *IMPLICITLY* saved on a disconnect * operation, in violation of the SCSI spec so we can safely * ignore SAVE/RESTORE pointers calls. * * Unfortunately, some disks violate the SCSI spec and * don't issue the required SAVE_POINTERS message before * disconnecting, and we have to break spec to remain * compatible. */ case SAVE_POINTERS: case RESTORE_POINTERS: /* Accept message by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); /* Enable reselect interrupts */ NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); break; case EXTENDED_MESSAGE: /* * Extended messages are sent in the following format : * Byte * 0 EXTENDED_MESSAGE == 1 * 1 length (includes one byte for code, doesn't * include first two bytes) * 2 code * 3..length+1 arguments * * Start the extended message buffer with the EXTENDED_MESSAGE * byte, since print_msg() wants the whole thing. */ extended_msg[0] = EXTENDED_MESSAGE; /* Accept first byte by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO); len = 2; data = extended_msg + 1; phase = PHASE_MSGIN; NCR5380_transfer_pio(instance, &phase, &len, &data); EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO, (int)extended_msg[1], (int)extended_msg[2]); if (!len && extended_msg[1] <= (sizeof (extended_msg) - 1)) { /* Accept third byte by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); len = extended_msg[1] - 1; data = extended_msg + 3; phase = PHASE_MSGIN; NCR5380_transfer_pio(instance, &phase, &len, &data); EXT_PRINTK("scsi%d: message received, residual %d\n", HOSTNO, len); switch (extended_msg[2]) { case EXTENDED_SDTR: case EXTENDED_WDTR: case EXTENDED_MODIFY_DATA_POINTER: case EXTENDED_EXTENDED_IDENTIFY: tmp = 0; } } else if (len) { printk(KERN_NOTICE "scsi%d: error receiving " "extended message\n", HOSTNO); tmp = 0; } else { printk(KERN_NOTICE "scsi%d: extended message " "code %02x length %d is too long\n", HOSTNO, extended_msg[2], extended_msg[1]); tmp = 0; } /* Fall through to reject message */ /* * If we get something weird that we aren't expecting, * reject it. */ default: if (!tmp) { printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO); print_msg (extended_msg); printk("\n"); } else if (tmp != EXTENDED_MESSAGE) printk(KERN_DEBUG "scsi%d: rejecting unknown " "message %02x from target %d, lun %d\n", HOSTNO, tmp, cmd->target, cmd->lun); else printk(KERN_DEBUG "scsi%d: rejecting unknown " "extended message " "code %02x, length %d from target %d, lun %d\n", HOSTNO, extended_msg[1], extended_msg[0], cmd->target, cmd->lun); msgout = MESSAGE_REJECT; NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); break; } /* switch (tmp) */ break; case PHASE_MSGOUT: len = 1; data = &msgout; hostdata->last_message = msgout; NCR5380_transfer_pio(instance, &phase, &len, &data); if (msgout == ABORT) { #ifdef SUPPORT_TAGS cmd_free_tag( cmd ); #else hostdata->busy[cmd->target] &= ~(1 << cmd->lun); #endif hostdata->connected = NULL; cmd->result = DID_ERROR << 16; #ifdef NCR5380_STATS collect_stats(hostdata, cmd); #endif cmd->scsi_done(cmd); NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); falcon_release_lock_if_possible( hostdata ); return; } msgout = NOP; break; case PHASE_CMDOUT: len = cmd->cmd_len; data = cmd->cmnd; /* * XXX for performance reasons, on machines with a * PSEUDO-DMA architecture we should probably * use the dma transfer function. */ NCR5380_transfer_pio(instance, &phase, &len, &data); break; case PHASE_STATIN: len = 1; data = &tmp; NCR5380_transfer_pio(instance, &phase, &len, &data); cmd->SCp.Status = tmp; break; default: printk("scsi%d: unknown phase\n", HOSTNO); NCR_PRINT(NDEBUG_ANY); } /* switch(phase) */ } /* if (tmp * SR_REQ) */ } /* while (1) */ } /* * Function : void NCR5380_reselect (struct Scsi_Host *instance) * * Purpose : does reselection, initializing the instance->connected * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q * nexus has been reestablished, * * Inputs : instance - this instance of the NCR5380. * */ static void NCR5380_reselect (struct Scsi_Host *instance) { SETUP_HOSTDATA(instance); unsigned char target_mask; unsigned char lun, phase; int len; #ifdef SUPPORT_TAGS unsigned char tag; #endif unsigned char msg[3]; unsigned char *data; Scsi_Cmnd *tmp = NULL, *prev; /* unsigned long flags; */ /* * Disable arbitration, etc. since the host adapter obviously * lost, and tell an interrupted NCR5380_select() to restart. */ NCR5380_write(MODE_REG, MR_BASE); hostdata->restart_select = 1; target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); RSL_PRINTK("scsi%d: reselect\n", HOSTNO); /* * At this point, we have detected that our SCSI ID is on the bus, * SEL is true and BSY was false for at least one bus settle delay * (400 ns). * * We must assert BSY ourselves, until the target drops the SEL * signal. */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); while (NCR5380_read(STATUS_REG) & SR_SEL); NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); /* * Wait for target to go into MSGIN. */ while (!(NCR5380_read(STATUS_REG) & SR_REQ)); len = 1; data = msg; phase = PHASE_MSGIN; NCR5380_transfer_pio(instance, &phase, &len, &data); if (!msg[0] & 0x80) { printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO); print_msg(msg); do_abort(instance); return; } lun = (msg[0] & 0x07); #ifdef SUPPORT_TAGS /* If the phase is still MSGIN, the target wants to send some more * messages. In case it supports tagged queuing, this is probably a * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. */ tag = TAG_NONE; if (phase == PHASE_MSGIN && setup_use_tagged_queuing) { /* Accept previous IDENTIFY message by clearing ACK */ NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE ); len = 2; data = msg+1; if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && msg[1] == SIMPLE_QUEUE_TAG) tag = msg[2]; TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at " "reselection\n", HOSTNO, target_mask, lun, tag); } #endif /* * Find the command corresponding to the I_T_L or I_T_L_Q nexus we * just reestablished, and remove it from the disconnected queue. */ for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) { if ((target_mask == (1 << tmp->target)) && (lun == tmp->lun) #ifdef SUPPORT_TAGS && (tag == tmp->tag) #endif ) { /* ++guenther: prevent race with falcon_release_lock */ falcon_dont_release++; if (prev) { REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); NEXT(prev) = NEXT(tmp); } else { REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp)); hostdata->disconnected_queue = NEXT(tmp); } NEXT(tmp) = NULL; break; } } if (!tmp) { printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d " #ifdef SUPPORT_TAGS "tag %d " #endif "not in disconnect_queue.\n", HOSTNO, target_mask, lun #ifdef SUPPORT_TAGS , tag #endif ); /* * Since we have an established nexus that we can't do anything * with, we must abort it. */ do_abort(instance); return; } /* Accept message by clearing ACK */ NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); hostdata->connected = tmp; RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n", HOSTNO, tmp->target, tmp->lun, tmp->tag); falcon_dont_release--; } /* * Function : int NCR5380_abort (Scsi_Cmnd *cmd) * * Purpose : abort a command * * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the * host byte of the result field to, if zero DID_ABORTED is * used. * * Returns : 0 - success, -1 on failure. * * XXX - there is no way to abort the command that is currently * connected, you have to wait for it to complete. If this is * a problem, we could implement longjmp() / setjmp(), setjmp() * called where the loop started in NCR5380_main(). */ #ifndef NCR5380_abort static #endif int NCR5380_abort (Scsi_Cmnd *cmd) { struct Scsi_Host *instance = cmd->host; SETUP_HOSTDATA(instance); Scsi_Cmnd *tmp, **prev; unsigned long flags; printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO); print_Scsi_Cmnd (cmd); NCR5380_print_status (instance); save_flags(flags); cli(); if (!IS_A_TT() && !falcon_got_lock) printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n", HOSTNO); ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)); #if 1 /* * Case 1 : If the command is the currently executing command, * we'll set the aborted flag and return control so that * information transfer routine can exit cleanly. */ if (hostdata->connected == cmd) { int rv; ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO); hostdata->aborted = 1; /* * We should perform BSY checking, and make sure we haven't slipped * into BUS FREE. */ /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */ /* * Since we can't change phases until we've completed the current * handshake, we have to source or sink a byte of data if the current * phase is not MSGOUT. */ /* * MSch: use the do_abort function instead ... unless there is need to wait * a longer period for the target to go into MSGOUT. */ rv = do_abort(instance); save_flags(flags); cli(); cmd->result = DID_ABORT << 16; #ifdef SUPPORT_TAGS cmd_free_tag( cmd ); #else hostdata->busy[cmd->target] &= ~(1 << cmd->lun); #endif restore_flags(flags); cmd->done(cmd); falcon_release_lock_if_possible( hostdata ); /* * Return control to the executing NCR drive so we can clear the * aborted flag and get back into our main loop. */ return rv ? SCSI_ABORT_SUCCESS : SCSI_ABORT_ERROR; } #endif /* * Case 2 : If the command hasn't been issued yet, we simply remove it * from the issue queue. */ for (prev = (Scsi_Cmnd **) &(hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) ) if (cmd == tmp) { REMOVE(5, *prev, tmp, NEXT(tmp)); (*prev) = NEXT(tmp); NEXT(tmp) = NULL; tmp->result = DID_ABORT << 16; restore_flags(flags); ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n", HOSTNO); /* Tagged queuing note: no tag to free here, hasn't been assigned * yet... */ tmp->done(tmp); falcon_release_lock_if_possible( hostdata ); return SCSI_ABORT_SUCCESS; } /* * Case 3 : If any commands are connected, we're going to fail the abort * and let the high level SCSI driver retry at a later time or * issue a reset. * * Timeouts, and therefore aborted commands, will be highly unlikely * and handling them cleanly in this situation would make the common * case of noresets less efficient, and would pollute our code. So, * we fail. */ if (hostdata->connected) { restore_flags(flags); ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO); return SCSI_ABORT_SNOOZE; } /* * Case 4: If the command is currently disconnected from the bus, and * there are no connected commands, we reconnect the I_T_L or * I_T_L_Q nexus associated with it, go into message out, and send * an abort message. * * This case is especially ugly. In order to reestablish the nexus, we * need to call NCR5380_select(). The easiest way to implement this * function was to abort if the bus was busy, and let the interrupt * handler triggered on the SEL for reselect take care of lost arbitrations * where necessary, meaning interrupts need to be enabled. * * When interrupts are enabled, the queues may change - so we * can't remove it from the disconnected queue before selecting it * because that could cause a failure in hashing the nexus if that * device reselected. * * Since the queues may change, we can't use the pointers from when we * first locate it. * * So, we must first locate the command, and if NCR5380_select() * succeeds, then issue the abort, relocate the command and remove * it from the disconnected queue. */ for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = NEXT(tmp)) if (cmd == tmp) { restore_flags(flags); ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO); if (NCR5380_select (instance, cmd, (int) cmd->tag)) return SCSI_ABORT_BUSY; ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO); do_abort (instance); save_flags(flags); cli(); for (prev = (Scsi_Cmnd **) &(hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) ) if (cmd == tmp) { REMOVE(5, *prev, tmp, NEXT(tmp)); *prev = NEXT(tmp); NEXT(tmp) = NULL; tmp->result = DID_ABORT << 16; /* We must unlock the tag/LUN immediately here, since the * target goes to BUS FREE and doesn't send us another * message (COMMAND_COMPLETE or the like) */ #ifdef SUPPORT_TAGS cmd_free_tag( tmp ); #else hostdata->busy[cmd->target] &= ~(1 << cmd->lun); #endif restore_flags(flags); tmp->done(tmp); falcon_release_lock_if_possible( hostdata ); return SCSI_ABORT_SUCCESS; } } /* * Case 5 : If we reached this point, the command was not found in any of * the queues. * * We probably reached this point because of an unlikely race condition * between the command completing successfully and the abortion code, * so we won't panic, but we will notify the user in case something really * broke. */ restore_flags(flags); printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n" KERN_INFO " before abortion\n", HOSTNO); /* Maybe it is sufficient just to release the ST-DMA lock... (if * possible at all) At least, we should check if the lock could be * released after the abort, in case it is kept due to some bug. */ falcon_release_lock_if_possible( hostdata ); return SCSI_ABORT_NOT_RUNNING; } /* * Function : int NCR5380_reset (Scsi_Cmnd *cmd, unsigned int reset_flags) * * Purpose : reset the SCSI bus. * * Returns : SCSI_RESET_WAKEUP * */ static int NCR5380_reset( Scsi_Cmnd *cmd, unsigned int reset_flags) { SETUP_HOSTDATA(cmd->host); int i; unsigned long flags; Scsi_Cmnd *connected, *disconnected_queue; if (!IS_A_TT() && !falcon_got_lock) printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n", H_NO(cmd) ); NCR5380_print_status (cmd->host); /* get in phase */ NCR5380_write( TARGET_COMMAND_REG, PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) )); /* assert RST */ NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST ); udelay (40); /* reset NCR registers */ NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE ); NCR5380_write( MODE_REG, MR_BASE ); NCR5380_write( TARGET_COMMAND_REG, 0 ); NCR5380_write( SELECT_ENABLE_REG, 0 ); /* ++roman: reset interrupt condition! otherwise no interrupts don't get * through anymore ... */ (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG ); #if 1 /* XXX Should now be done by midlevel code, bug isn't XXX */ /* After the reset, there are no more connected or disconnected commands * and no busy units; to avoid problems with re-inserting the commands * into the issue_queue (via scsi_done()), the aborted commands are * remembered in local variables first. */ save_flags(flags); cli(); connected = (Scsi_Cmnd *)hostdata->connected; hostdata->connected = NULL; disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue; hostdata->disconnected_queue = NULL; #ifdef SUPPORT_TAGS free_all_tags(); #endif for( i = 0; i < 8; ++i ) hostdata->busy[i] = 0; #ifdef REAL_DMA hostdata->dma_len = 0; #endif restore_flags(flags); if ((cmd = connected)) { ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd)); cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); cmd->scsi_done( cmd ); } for (i = 0; (cmd = disconnected_queue); ++i) { disconnected_queue = NEXT(cmd); NEXT(cmd) = NULL; cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); cmd->scsi_done( cmd ); } if (i > 0) ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i); /* The Falcon lock should be released after a reset... */ /* ++guenther: moved to atari_scsi_reset(), to prevent a race between * unlocking and enabling dma interrupt. */ /* falcon_release_lock_if_possible( hostdata );*/ #endif /* 1 */ return SCSI_RESET_WAKEUP; } /* Local Variables: */ /* tab-width: 8 */ /* End: */
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