From 312f7da2824c82800ee78d6190f12854456957af Mon Sep 17 00:00:00 2001 From: Albert Lee Date: Tue, 27 Sep 2005 17:38:03 +0800 Subject: [PATCH] libata: interrupt driven pio for libata-core - add PIO_ST_FIRST for the state before sending ATAPI CDB or sending "ATA PIO data out" first data block. - add ATA_TFLAG_POLLING and ATA_DFLAG_CDB_INTR flags - remove the ATA_FLAG_NOINTR flag since the interrupt handler is now aware of the states - modify ata_pio_sector() and atapi_pio_bytes() to work in the interrupt context - modify the ata_host_intr() to handle PIO interrupts - modify ata_qc_issue_prot() to initialize states - atapi_packet_task() changed to handle "ATA PIO data out" first data block - support the pre-ATA4 ATAPI device which raise interrupt when ready to receive CDB Signed-off-by: Albert Lee Signed-off-by: Jeff Garzik --- drivers/scsi/libata-core.c | 333 ++++++++++++++++++++++++++++++++++++--------- include/linux/ata.h | 3 + include/linux/libata.h | 4 +- 3 files changed, 271 insertions(+), 69 deletions(-) diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index c4fcdc30f18c10..cc2d1308826ea5 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -1292,6 +1292,9 @@ retry: ap->cdb_len = (unsigned int) rc; ap->host->max_cmd_len = (unsigned char) ap->cdb_len; + if (ata_id_cdb_intr(dev->id)) + dev->flags |= ATA_DFLAG_CDB_INTR; + /* print device info to dmesg */ printk(KERN_INFO "ata%u: dev %u ATAPI, max %s\n", ap->id, device, @@ -2405,7 +2408,6 @@ void ata_poll_qc_complete(struct ata_queued_cmd *qc, u8 drv_stat) unsigned long flags; spin_lock_irqsave(&ap->host_set->lock, flags); - ap->flags &= ~ATA_FLAG_NOINTR; ata_irq_on(ap); ata_qc_complete(qc, drv_stat); spin_unlock_irqrestore(&ap->host_set->lock, flags); @@ -2660,6 +2662,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) struct page *page; unsigned int offset; unsigned char *buf; + unsigned long flags; if (qc->cursect == (qc->nsect - 1)) ap->hsm_task_state = HSM_ST_LAST; @@ -2671,7 +2674,8 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) page = nth_page(page, (offset >> PAGE_SHIFT)); offset %= PAGE_SIZE; - buf = kmap(page) + offset; + local_irq_save(flags); + buf = kmap_atomic(page, KM_IRQ0) + offset; qc->cursect++; qc->cursg_ofs++; @@ -2687,7 +2691,8 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) do_write = (qc->tf.flags & ATA_TFLAG_WRITE); ata_data_xfer(ap, buf, ATA_SECT_SIZE, do_write); - kunmap(page); + kunmap_atomic(buf - offset, KM_IRQ0); + local_irq_restore(flags); } /** @@ -2710,6 +2715,7 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) struct page *page; unsigned char *buf; unsigned int offset, count; + unsigned long flags; if (qc->curbytes + bytes >= qc->nbytes) ap->hsm_task_state = HSM_ST_LAST; @@ -2753,7 +2759,8 @@ next_sg: /* don't cross page boundaries */ count = min(count, (unsigned int)PAGE_SIZE - offset); - buf = kmap(page) + offset; + local_irq_save(flags); + buf = kmap_atomic(page, KM_IRQ0) + offset; bytes -= count; qc->curbytes += count; @@ -2769,7 +2776,8 @@ next_sg: /* do the actual data transfer */ ata_data_xfer(ap, buf, count, do_write); - kunmap(page); + kunmap_atomic(buf - offset, KM_IRQ0); + local_irq_restore(flags); if (bytes) goto next_sg; @@ -2808,6 +2816,8 @@ static void atapi_pio_bytes(struct ata_queued_cmd *qc) if (do_write != i_write) goto err_out; + VPRINTK("ata%u: xfering %d bytes\n", ap->id, bytes); + __atapi_pio_bytes(qc, bytes); return; @@ -3054,6 +3064,8 @@ static void ata_qc_timeout(struct ata_queued_cmd *qc) printk(KERN_ERR "ata%u: command 0x%x timeout, stat 0x%x host_stat 0x%x\n", ap->id, qc->tf.command, drv_stat, host_stat); + ap->hsm_task_state = HSM_ST_IDLE; + /* complete taskfile transaction */ ata_qc_complete(qc, drv_stat); break; @@ -3344,43 +3356,96 @@ int ata_qc_issue_prot(struct ata_queued_cmd *qc) { struct ata_port *ap = qc->ap; + /* select the device */ ata_dev_select(ap, qc->dev->devno, 1, 0); + /* start the command */ switch (qc->tf.protocol) { case ATA_PROT_NODATA: + if (qc->tf.flags & ATA_TFLAG_POLLING) + ata_qc_set_polling(qc); + ata_tf_to_host_nolock(ap, &qc->tf); + ap->hsm_task_state = HSM_ST_LAST; + + if (qc->tf.flags & ATA_TFLAG_POLLING) + queue_work(ata_wq, &ap->pio_task); + break; case ATA_PROT_DMA: + assert(!(qc->tf.flags & ATA_TFLAG_POLLING)); + ap->ops->tf_load(ap, &qc->tf); /* load tf registers */ ap->ops->bmdma_setup(qc); /* set up bmdma */ ap->ops->bmdma_start(qc); /* initiate bmdma */ + ap->hsm_task_state = HSM_ST_LAST; break; - case ATA_PROT_PIO: /* load tf registers, initiate polling pio */ - ata_qc_set_polling(qc); + case ATA_PROT_PIO: + if (qc->tf.flags & ATA_TFLAG_POLLING) + ata_qc_set_polling(qc); + ata_tf_to_host_nolock(ap, &qc->tf); - ap->hsm_task_state = HSM_ST; - queue_work(ata_wq, &ap->pio_task); + + if (qc->tf.flags & ATA_TFLAG_POLLING) { + /* polling PIO */ + ap->hsm_task_state = HSM_ST; + queue_work(ata_wq, &ap->pio_task); + } else { + /* interrupt driven PIO */ + if (qc->tf.flags & ATA_TFLAG_WRITE) { + /* PIO data out protocol */ + ap->hsm_task_state = HSM_ST_FIRST; + queue_work(ata_wq, &ap->packet_task); + + /* send first data block by polling */ + } else { + /* PIO data in protocol */ + ap->hsm_task_state = HSM_ST; + + /* interrupt handler takes over from here */ + } + } + break; case ATA_PROT_ATAPI: - ata_qc_set_polling(qc); + if (qc->tf.flags & ATA_TFLAG_POLLING) + ata_qc_set_polling(qc); + ata_tf_to_host_nolock(ap, &qc->tf); - queue_work(ata_wq, &ap->packet_task); + ap->hsm_task_state = HSM_ST_FIRST; + + /* send cdb by polling if no cdb interrupt */ + if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) || + (qc->tf.flags & ATA_TFLAG_POLLING)) + queue_work(ata_wq, &ap->packet_task); break; case ATA_PROT_ATAPI_NODATA: - ap->flags |= ATA_FLAG_NOINTR; + if (qc->tf.flags & ATA_TFLAG_POLLING) + ata_qc_set_polling(qc); + ata_tf_to_host_nolock(ap, &qc->tf); - queue_work(ata_wq, &ap->packet_task); + ap->hsm_task_state = HSM_ST_FIRST; + + /* send cdb by polling if no cdb interrupt */ + if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) || + (qc->tf.flags & ATA_TFLAG_POLLING)) + queue_work(ata_wq, &ap->packet_task); break; case ATA_PROT_ATAPI_DMA: - ap->flags |= ATA_FLAG_NOINTR; + assert(!(qc->tf.flags & ATA_TFLAG_POLLING)); + ap->ops->tf_load(ap, &qc->tf); /* load tf registers */ ap->ops->bmdma_setup(qc); /* set up bmdma */ - queue_work(ata_wq, &ap->packet_task); + ap->hsm_task_state = HSM_ST_FIRST; + + /* send cdb by polling if no cdb interrupt */ + if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) + queue_work(ata_wq, &ap->packet_task); break; default: @@ -3622,6 +3687,42 @@ void ata_bmdma_stop(struct ata_queued_cmd *qc) ata_altstatus(ap); /* dummy read */ } +/** + * atapi_send_cdb - Write CDB bytes to hardware + * @ap: Port to which ATAPI device is attached. + * @qc: Taskfile currently active + * + * When device has indicated its readiness to accept + * a CDB, this function is called. Send the CDB. + * + * LOCKING: + * caller. + */ + +static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc) +{ + /* send SCSI cdb */ + DPRINTK("send cdb\n"); + assert(ap->cdb_len >= 12); + + ata_data_xfer(ap, qc->cdb, ap->cdb_len, 1); + ata_altstatus(ap); /* flush */ + + switch (qc->tf.protocol) { + case ATA_PROT_ATAPI: + ap->hsm_task_state = HSM_ST; + break; + case ATA_PROT_ATAPI_NODATA: + ap->hsm_task_state = HSM_ST_LAST; + break; + case ATA_PROT_ATAPI_DMA: + ap->hsm_task_state = HSM_ST_LAST; + /* initiate bmdma */ + ap->ops->bmdma_start(qc); + break; + } +} + /** * ata_host_intr - Handle host interrupt for given (port, task) * @ap: Port on which interrupt arrived (possibly...) @@ -3641,47 +3742,142 @@ void ata_bmdma_stop(struct ata_queued_cmd *qc) inline unsigned int ata_host_intr (struct ata_port *ap, struct ata_queued_cmd *qc) { - u8 status, host_stat; - - switch (qc->tf.protocol) { + u8 status, host_stat = 0; - case ATA_PROT_DMA: - case ATA_PROT_ATAPI_DMA: - case ATA_PROT_ATAPI: - /* check status of DMA engine */ - host_stat = ap->ops->bmdma_status(ap); - VPRINTK("ata%u: host_stat 0x%X\n", ap->id, host_stat); + VPRINTK("ata%u: protocol %d task_state %d\n", + ap->id, qc->tf.protocol, ap->hsm_task_state); - /* if it's not our irq... */ - if (!(host_stat & ATA_DMA_INTR)) + /* Check whether we are expecting interrupt in this state */ + switch (ap->hsm_task_state) { + case HSM_ST_FIRST: + /* Check the ATA_DFLAG_CDB_INTR flag is enough here. + * The flag was turned on only for atapi devices. + * No need to check is_atapi_taskfile(&qc->tf) again. + */ + if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) goto idle_irq; + break; + case HSM_ST_LAST: + if (qc->tf.protocol == ATA_PROT_DMA || + qc->tf.protocol == ATA_PROT_ATAPI_DMA) { + /* check status of DMA engine */ + host_stat = ap->ops->bmdma_status(ap); + VPRINTK("ata%u: host_stat 0x%X\n", ap->id, host_stat); + + /* if it's not our irq... */ + if (!(host_stat & ATA_DMA_INTR)) + goto idle_irq; + + /* before we do anything else, clear DMA-Start bit */ + ap->ops->bmdma_stop(qc); + } + break; + case HSM_ST: + break; + default: + goto idle_irq; + } - /* before we do anything else, clear DMA-Start bit */ - ap->ops->bmdma_stop(qc); + /* check altstatus */ + status = ata_altstatus(ap); + if (status & ATA_BUSY) + goto idle_irq; - /* fall through */ + /* check main status, clearing INTRQ */ + status = ata_chk_status(ap); + if (unlikely(status & ATA_BUSY)) + goto idle_irq; - case ATA_PROT_ATAPI_NODATA: - case ATA_PROT_NODATA: - /* check altstatus */ - status = ata_altstatus(ap); - if (status & ATA_BUSY) - goto idle_irq; + DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n", + ap->id, qc->tf.protocol, ap->hsm_task_state, status); - /* check main status, clearing INTRQ */ - status = ata_chk_status(ap); - if (unlikely(status & ATA_BUSY)) - goto idle_irq; - DPRINTK("ata%u: protocol %d (dev_stat 0x%X)\n", - ap->id, qc->tf.protocol, status); + /* ack bmdma irq events */ + ap->ops->irq_clear(ap); - /* ack bmdma irq events */ - ap->ops->irq_clear(ap); + /* check error */ + if (unlikely((status & ATA_ERR) || (host_stat & ATA_DMA_ERR))) + ap->hsm_task_state = HSM_ST_ERR; + +fsm_start: + switch (ap->hsm_task_state) { + case HSM_ST_FIRST: + /* Some pre-ATAPI-4 devices assert INTRQ + * at this state when ready to receive CDB. + */ + + /* check device status */ + if (unlikely((status & (ATA_BUSY | ATA_DRQ)) != ATA_DRQ)) { + /* Wrong status. Let EH handle this */ + ap->hsm_task_state = HSM_ST_ERR; + goto fsm_start; + } + + atapi_send_cdb(ap, qc); + + break; + + case HSM_ST: + /* complete command or read/write the data register */ + if (qc->tf.protocol == ATA_PROT_ATAPI) { + /* ATAPI PIO protocol */ + if ((status & ATA_DRQ) == 0) { + /* no more data to transfer */ + ap->hsm_task_state = HSM_ST_LAST; + goto fsm_start; + } + + atapi_pio_bytes(qc); + + if (unlikely(ap->hsm_task_state == HSM_ST_ERR)) + /* bad ireason reported by device */ + goto fsm_start; + + } else { + /* ATA PIO protocol */ + if (unlikely((status & ATA_DRQ) == 0)) { + /* handle BSY=0, DRQ=0 as error */ + ap->hsm_task_state = HSM_ST_ERR; + goto fsm_start; + } + + ata_pio_sector(qc); + + if (ap->hsm_task_state == HSM_ST_LAST && + (!(qc->tf.flags & ATA_TFLAG_WRITE))) { + /* all data read */ + ata_altstatus(ap); + status = ata_chk_status(ap); + goto fsm_start; + } + } + + ata_altstatus(ap); /* flush */ + break; + + case HSM_ST_LAST: + if (unlikely(status & ATA_DRQ)) { + /* handle DRQ=1 as error */ + ap->hsm_task_state = HSM_ST_ERR; + goto fsm_start; + } + + /* no more data to transfer */ + DPRINTK("ata%u: command complete, drv_stat 0x%x\n", + ap->id, status); + + ap->hsm_task_state = HSM_ST_IDLE; /* complete taskfile transaction */ ata_qc_complete(qc, status); break; + case HSM_ST_ERR: + printk(KERN_ERR "ata%u: command error, drv_stat 0x%x host_stat 0x%x\n", + ap->id, status, host_stat); + + ap->hsm_task_state = HSM_ST_IDLE; + ata_qc_complete(qc, status | ATA_ERR); + break; default: goto idle_irq; } @@ -3733,11 +3929,11 @@ irqreturn_t ata_interrupt (int irq, void *dev_instance, struct pt_regs *regs) ap = host_set->ports[i]; if (ap && - !(ap->flags & (ATA_FLAG_PORT_DISABLED | ATA_FLAG_NOINTR))) { + !(ap->flags & ATA_FLAG_PORT_DISABLED)) { struct ata_queued_cmd *qc; qc = ata_qc_from_tag(ap, ap->active_tag); - if (qc && (!(qc->tf.ctl & ATA_NIEN)) && + if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING)) && (qc->flags & ATA_QCFLAG_ACTIVE)) handled |= ata_host_intr(ap, qc); } @@ -3767,6 +3963,7 @@ static void atapi_packet_task(void *_data) struct ata_port *ap = _data; struct ata_queued_cmd *qc; u8 status; + unsigned long flags; qc = ata_qc_from_tag(ap, ap->active_tag); assert(qc != NULL); @@ -3782,38 +3979,40 @@ static void atapi_packet_task(void *_data) if ((status & (ATA_BUSY | ATA_DRQ)) != ATA_DRQ) goto err_out; - /* send SCSI cdb */ - DPRINTK("send cdb\n"); - assert(ap->cdb_len >= 12); + /* Send the CDB (atapi) or the first data block (ata pio out). + * During the state transition, interrupt handler shouldn't + * be invoked before the data transfer is complete and + * hsm_task_state is changed. Hence, the following locking. + */ + spin_lock_irqsave(&ap->host_set->lock, flags); - if (qc->tf.protocol == ATA_PROT_ATAPI_DMA || - qc->tf.protocol == ATA_PROT_ATAPI_NODATA) { - unsigned long flags; + if (is_atapi_taskfile(&qc->tf)) { + /* send CDB */ + atapi_send_cdb(ap, qc); - /* Once we're done issuing command and kicking bmdma, - * irq handler takes over. To not lose irq, we need - * to clear NOINTR flag before sending cdb, but - * interrupt handler shouldn't be invoked before we're - * finished. Hence, the following locking. - */ - spin_lock_irqsave(&ap->host_set->lock, flags); - ap->flags &= ~ATA_FLAG_NOINTR; - ata_data_xfer(ap, qc->cdb, ap->cdb_len, 1); - if (qc->tf.protocol == ATA_PROT_ATAPI_DMA) - ap->ops->bmdma_start(qc); /* initiate bmdma */ - spin_unlock_irqrestore(&ap->host_set->lock, flags); + if (qc->tf.flags & ATA_TFLAG_POLLING) + queue_work(ata_wq, &ap->pio_task); } else { - ata_data_xfer(ap, qc->cdb, ap->cdb_len, 1); + /* PIO data out protocol. + * send first data block. + */ - /* PIO commands are handled by polling */ + /* ata_pio_sector() might change the state to HSM_ST_LAST. + * so, the state is changed here before ata_pio_sector(). + */ ap->hsm_task_state = HSM_ST; - queue_work(ata_wq, &ap->pio_task); + ata_pio_sector(qc); + ata_altstatus(ap); /* flush */ + + /* interrupt handler takes over from here */ } + spin_unlock_irqrestore(&ap->host_set->lock, flags); + return; err_out: - ata_poll_qc_complete(qc, ATA_ERR); + ata_pio_error(ap); } diff --git a/include/linux/ata.h b/include/linux/ata.h index a5b74efab0679a..6fec2f6f2d5912 100644 --- a/include/linux/ata.h +++ b/include/linux/ata.h @@ -181,6 +181,7 @@ enum { ATA_TFLAG_ISADDR = (1 << 1), /* enable r/w to nsect/lba regs */ ATA_TFLAG_DEVICE = (1 << 2), /* enable r/w to device reg */ ATA_TFLAG_WRITE = (1 << 3), /* data dir: host->dev==1 (write) */ + ATA_TFLAG_POLLING = (1 << 4), /* set nIEN to 1 and use polling */ }; enum ata_tf_protocols { @@ -250,6 +251,8 @@ struct ata_taskfile { ((u64) (id)[(n) + 1] << 16) | \ ((u64) (id)[(n) + 0]) ) +#define ata_id_cdb_intr(id) (((id)[0] & 0x60) == 0x20) + static inline int atapi_cdb_len(u16 *dev_id) { u16 tmp = dev_id[0] & 0x3; diff --git a/include/linux/libata.h b/include/linux/libata.h index bb2d916bce4447..9ac2b69df3c1c5 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -97,6 +97,7 @@ enum { ATA_DFLAG_LBA48 = (1 << 0), /* device supports LBA48 */ ATA_DFLAG_PIO = (1 << 1), /* device currently in PIO mode */ ATA_DFLAG_LOCK_SECTORS = (1 << 2), /* don't adjust max_sectors */ + ATA_DFLAG_CDB_INTR = (1 << 3), /* device asserts INTRQ when ready for CDB */ ATA_DEV_UNKNOWN = 0, /* unknown device */ ATA_DEV_ATA = 1, /* ATA device */ @@ -115,8 +116,6 @@ enum { ATA_FLAG_MMIO = (1 << 6), /* use MMIO, not PIO */ ATA_FLAG_SATA_RESET = (1 << 7), /* use COMRESET */ ATA_FLAG_PIO_DMA = (1 << 8), /* PIO cmds via DMA */ - ATA_FLAG_NOINTR = (1 << 9), /* FIXME: Remove this once - * proper HSM is in place. */ ATA_QCFLAG_ACTIVE = (1 << 1), /* cmd not yet ack'd to scsi lyer */ ATA_QCFLAG_SG = (1 << 3), /* have s/g table? */ @@ -165,6 +164,7 @@ enum hsm_task_states { HSM_ST_LAST, HSM_ST_LAST_POLL, HSM_ST_ERR, + HSM_ST_FIRST, }; /* forward declarations */ -- cgit 1.2.3-korg