diff options
author | Ingo Molnar <mingo@elte.hu> | 2008-06-16 11:17:19 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2008-06-16 11:17:19 +0200 |
commit | ed9e4996d9a123b7550e63713d563f524fa9d9f0 (patch) | |
tree | a9be05d357b407aac80118b86f25d21a5dbdfc88 /drivers/ata/libata-sff.c | |
parent | 4d2df795f0c3eb91f97a666f47716121a2f166ed (diff) | |
parent | 066519068ad2fbe98c7f45552b1f592903a9c8c8 (diff) |
Merge branch 'linus' into tracing/sysproftip-tracing-sysprof-2008-06-16_09.17_Mon
Diffstat (limited to 'drivers/ata/libata-sff.c')
-rw-r--r-- | drivers/ata/libata-sff.c | 115 |
1 files changed, 100 insertions, 15 deletions
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 3c2d2289f85e..215d18672a5a 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -247,7 +247,7 @@ u8 ata_sff_check_status(struct ata_port *ap) * LOCKING: * Inherited from caller. */ -u8 ata_sff_altstatus(struct ata_port *ap) +static u8 ata_sff_altstatus(struct ata_port *ap) { if (ap->ops->sff_check_altstatus) return ap->ops->sff_check_altstatus(ap); @@ -256,6 +256,93 @@ u8 ata_sff_altstatus(struct ata_port *ap) } /** + * ata_sff_irq_status - Check if the device is busy + * @ap: port where the device is + * + * Determine if the port is currently busy. Uses altstatus + * if available in order to avoid clearing shared IRQ status + * when finding an IRQ source. Non ctl capable devices don't + * share interrupt lines fortunately for us. + * + * LOCKING: + * Inherited from caller. + */ +static u8 ata_sff_irq_status(struct ata_port *ap) +{ + u8 status; + + if (ap->ops->sff_check_altstatus || ap->ioaddr.altstatus_addr) { + status = ata_sff_altstatus(ap); + /* Not us: We are busy */ + if (status & ATA_BUSY) + return status; + } + /* Clear INTRQ latch */ + status = ap->ops->sff_check_status(ap); + return status; +} + +/** + * ata_sff_sync - Flush writes + * @ap: Port to wait for. + * + * CAUTION: + * If we have an mmio device with no ctl and no altstatus + * method this will fail. No such devices are known to exist. + * + * LOCKING: + * Inherited from caller. + */ + +static void ata_sff_sync(struct ata_port *ap) +{ + if (ap->ops->sff_check_altstatus) + ap->ops->sff_check_altstatus(ap); + else if (ap->ioaddr.altstatus_addr) + ioread8(ap->ioaddr.altstatus_addr); +} + +/** + * ata_sff_pause - Flush writes and wait 400nS + * @ap: Port to pause for. + * + * CAUTION: + * If we have an mmio device with no ctl and no altstatus + * method this will fail. No such devices are known to exist. + * + * LOCKING: + * Inherited from caller. + */ + +void ata_sff_pause(struct ata_port *ap) +{ + ata_sff_sync(ap); + ndelay(400); +} + +/** + * ata_sff_dma_pause - Pause before commencing DMA + * @ap: Port to pause for. + * + * Perform I/O fencing and ensure sufficient cycle delays occur + * for the HDMA1:0 transition + */ + +void ata_sff_dma_pause(struct ata_port *ap) +{ + if (ap->ops->sff_check_altstatus || ap->ioaddr.altstatus_addr) { + /* An altstatus read will cause the needed delay without + messing up the IRQ status */ + ata_sff_altstatus(ap); + return; + } + /* There are no DMA controllers without ctl. BUG here to ensure + we never violate the HDMA1:0 transition timing and risk + corruption. */ + BUG(); +} + +/** * ata_sff_busy_sleep - sleep until BSY clears, or timeout * @ap: port containing status register to be polled * @tmout_pat: impatience timeout @@ -742,7 +829,7 @@ static void ata_pio_sectors(struct ata_queued_cmd *qc) } else ata_pio_sector(qc); - ata_sff_altstatus(qc->ap); /* flush */ + ata_sff_sync(qc->ap); /* flush */ } /** @@ -763,8 +850,9 @@ static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc) WARN_ON(qc->dev->cdb_len < 12); ap->ops->sff_data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1); - ata_sff_altstatus(ap); /* flush */ - + ata_sff_sync(ap); + /* FIXME: If the CDB is for DMA do we need to do the transition delay + or is bmdma_start guaranteed to do it ? */ switch (qc->tf.protocol) { case ATAPI_PROT_PIO: ap->hsm_task_state = HSM_ST; @@ -905,7 +993,7 @@ static void atapi_pio_bytes(struct ata_queued_cmd *qc) if (unlikely(__atapi_pio_bytes(qc, bytes))) goto err_out; - ata_sff_altstatus(ap); /* flush */ + ata_sff_sync(ap); /* flush */ return; @@ -1489,14 +1577,10 @@ inline unsigned int ata_sff_host_intr(struct ata_port *ap, goto idle_irq; } - /* check altstatus */ - status = ata_sff_altstatus(ap); - if (status & ATA_BUSY) - goto idle_irq; - /* check main status, clearing INTRQ */ - status = ap->ops->sff_check_status(ap); - if (unlikely(status & ATA_BUSY)) + /* check main status, clearing INTRQ if needed */ + status = ata_sff_irq_status(ap); + if (status & ATA_BUSY) goto idle_irq; /* ack bmdma irq events */ @@ -2030,7 +2114,7 @@ void ata_sff_error_handler(struct ata_port *ap) ap->ops->bmdma_stop(qc); } - ata_sff_altstatus(ap); + ata_sff_sync(ap); /* FIXME: We don't need this */ ap->ops->sff_check_status(ap); ap->ops->sff_irq_clear(ap); @@ -2203,7 +2287,7 @@ void ata_bmdma_stop(struct ata_queued_cmd *qc) mmio + ATA_DMA_CMD); /* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */ - ata_sff_altstatus(ap); /* dummy read */ + ata_sff_dma_pause(ap); } /** @@ -2722,7 +2806,8 @@ EXPORT_SYMBOL_GPL(ata_sff_qc_prep); EXPORT_SYMBOL_GPL(ata_sff_dumb_qc_prep); EXPORT_SYMBOL_GPL(ata_sff_dev_select); EXPORT_SYMBOL_GPL(ata_sff_check_status); -EXPORT_SYMBOL_GPL(ata_sff_altstatus); +EXPORT_SYMBOL_GPL(ata_sff_dma_pause); +EXPORT_SYMBOL_GPL(ata_sff_pause); EXPORT_SYMBOL_GPL(ata_sff_busy_sleep); EXPORT_SYMBOL_GPL(ata_sff_wait_ready); EXPORT_SYMBOL_GPL(ata_sff_tf_load); |