diff options
| -rw-r--r-- | drivers/scsi/atari_NCR5380.c | 205 |
1 files changed, 85 insertions, 120 deletions
diff --git a/drivers/scsi/atari_NCR5380.c b/drivers/scsi/atari_NCR5380.c index 1331b8cf5fe9..7bbfa1b777c3 100644 --- a/drivers/scsi/atari_NCR5380.c +++ b/drivers/scsi/atari_NCR5380.c @@ -104,27 +104,7 @@ /* * 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 @@ -139,11 +119,6 @@ * 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. * * Issues specific to the NCR5380 : * @@ -168,19 +143,17 @@ * 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. + * which is started from a workqueue for each NCR5380 host in the + * system. 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. + * queue, and NCR5380_main tries to find more work. If 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 @@ -206,6 +179,9 @@ * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically * for commands that return with a CHECK CONDITION status. * + * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential + * transceivers. + * * LINKED - if defined, linked commands are supported. * * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. @@ -218,6 +194,9 @@ * * NCR5380_write(register, value) - write to the specific register * + * NCR5380_implementation_fields - additional fields needed for this + * specific implementation of the NCR5380 + * * Either real DMA *or* pseudo DMA may be implemented * REAL functions : * NCR5380_REAL_DMA should be defined if real DMA is to be used. @@ -236,20 +215,6 @@ * 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 - * - * 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, @@ -489,13 +454,11 @@ static void merge_contiguous_buffers(struct scsi_cmnd *cmd) #endif /* !defined(CONFIG_SUN3) */ } -/* - * Function : void initialize_SCp(struct scsi_cmnd *cmd) - * - * Purpose : initialize the saved data pointers for cmd to point to the - * start of the buffer. +/** + * initialize_SCp - init the scsi pointer field + * @cmd: command block to set up * - * Inputs : cmd - scsi_cmnd structure to have pointers reset. + * Set up the internal fields in the SCSI command. */ static inline void initialize_SCp(struct scsi_cmnd *cmd) @@ -548,12 +511,11 @@ static struct { {0, NULL} }; -/* - * Function : void NCR5380_print(struct Scsi_Host *instance) - * - * Purpose : print the SCSI bus signals for debugging purposes +/** + * NCR5380_print - print scsi bus signals + * @instance: adapter state to dump * - * Input : instance - which NCR5380 + * Print the SCSI bus signals for debugging purposes */ static void NCR5380_print(struct Scsi_Host *instance) @@ -596,12 +558,13 @@ static struct { {PHASE_UNKNOWN, "UNKNOWN"} }; -/* - * Function : void NCR5380_print_phase(struct Scsi_Host *instance) +/** + * NCR5380_print_phase - show SCSI phase + * @instance: adapter to dump * - * Purpose : print the current SCSI phase for debugging purposes + * Print the current SCSI phase for debugging purposes * - * Input : instance - which NCR5380 + * Locks: none */ static void NCR5380_print_phase(struct Scsi_Host *instance) @@ -710,13 +673,12 @@ static void prepare_info(struct Scsi_Host *instance) ""); } -/* - * 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. +/** + * NCR5380_print_status - dump controller info + * @instance: controller to dump * - * Inputs : instance, pointer to this instance. + * Print commands in the various queues, called from NCR5380_abort + * to aid debugging. */ static void lprint_Scsi_Cmnd(struct scsi_cmnd *cmd) @@ -807,16 +769,18 @@ static int __maybe_unused NCR5380_show_info(struct seq_file *m, return 0; } -/* - * Function : void NCR5380_init (struct Scsi_Host *instance) - * - * Purpose : initializes *instance and corresponding 5380 chip. +/** + * NCR5380_init - initialise an NCR5380 + * @instance: adapter to configure + * @flags: control flags * - * Inputs : instance - instantiation of the 5380 driver. + * Initializes *instance and corresponding 5380 chip, + * with flags OR'd into the initial flags value. * * Notes : I assume that the host, hostno, and id bits have been - * set correctly. I don't care about the irq and other fields. + * set correctly. I don't care about the irq and other fields. * + * Returns 0 for success */ static int __init NCR5380_init(struct Scsi_Host *instance, int flags) @@ -861,27 +825,26 @@ static int __init NCR5380_init(struct Scsi_Host *instance, int flags) return 0; } +/** + * NCR5380_exit - remove an NCR5380 + * @instance: adapter to remove + * + * Assumes that no more work can be queued (e.g. by NCR5380_intr). + */ + static void NCR5380_exit(struct Scsi_Host *instance) { - /* Empty, as we didn't schedule any delayed work */ + cancel_work_sync(&NCR5380_tqueue); } -/* - * Function : int NCR5380_queue_command (struct scsi_cmnd *cmd, - * void (*done)(struct 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. +/** + * NCR5380_queue_command - queue a command + * @instance: the relevant SCSI adapter + * @cmd: SCSI command * + * 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. */ static int NCR5380_queue_command(struct Scsi_Host *instance, @@ -935,6 +898,13 @@ static int NCR5380_queue_command(struct Scsi_Host *instance, local_irq_save(flags); + /* + * 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. + */ + if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { LIST(cmd, hostdata->issue_queue); SET_NEXT(cmd, hostdata->issue_queue); @@ -977,16 +947,15 @@ static inline void maybe_release_dma_irq(struct Scsi_Host *instance) NCR5380_release_dma_irq(instance); } -/* - * Function : NCR5380_main (void) +/** + * NCR5380_main - NCR state machines * - * 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. + * 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. + * Locks: called as its own thread with no locks held. */ static void NCR5380_main(struct work_struct *work) @@ -1239,15 +1208,14 @@ static void NCR5380_dma_complete(struct Scsi_Host *instance) #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. +/** + * NCR5380_intr - generic NCR5380 irq handler + * @irq: interrupt number + * @dev_id: device info * + * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses + * from the disconnected queue, and restarting NCR5380_main() + * as required. */ static irqreturn_t NCR5380_intr(int irq, void *dev_id) @@ -1540,7 +1508,7 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) * selection. */ - timeout = jiffies + 25; + timeout = jiffies + (250 * HZ / 1000); /* * XXX very interesting - we're seeing a bounce where the BSY we @@ -2123,9 +2091,8 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance) * 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 %llu to slow handshake\n", HOSTNO, - cmd->device->id, cmd->device->lun); + scmd_printk(KERN_INFO, cmd, + "switching to slow handshake\n"); cmd->device->borken = 1; NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); @@ -2445,20 +2412,18 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance) */ default: if (!tmp) { - printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO); + printk(KERN_INFO "scsi%d: rejecting message ", + instance->host_no); spi_print_msg(extended_msg); printk("\n"); } else if (tmp != EXTENDED_MESSAGE) - printk(KERN_DEBUG "scsi%d: rejecting unknown " - "message %02x from target %d, lun %llu\n", - HOSTNO, tmp, cmd->device->id, cmd->device->lun); + scmd_printk(KERN_INFO, cmd, + "rejecting unknown message %02x\n", + tmp); else - printk(KERN_DEBUG "scsi%d: rejecting unknown " - "extended message " - "code %02x, length %d from target %d, lun %llu\n", - HOSTNO, extended_msg[1], extended_msg[0], - cmd->device->id, cmd->device->lun); - + scmd_printk(KERN_INFO, cmd, + "rejecting unknown extended message code %02x, length %d\n", + extended_msg[1], extended_msg[0]); msgout = MESSAGE_REJECT; NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); |
