From e3e4385f6181f434c0d786998ad1d0eef4e21c9b Mon Sep 17 00:00:00 2001 From: Stuart MENEFY Date: Tue, 10 Mar 2009 11:38:13 +0000 Subject: libata: Keep shadow last_ctl up to date during resets libata keeps a shadow copy of the ATA CTL register (which is write only), and only writes to the hardware when the required value doesn't match the shadow. However this copy wasn't being maintained when performing reset functions. This could cause problems for the first operation after a reset when the correct value might not be written to the CTL register. This problem was observed when hotplugging a drive: the identify command was being issued with interrupts enabled, when they should have been disabled. Signed-off-by: Stuart Menefy Signed-off-by: Jeff Garzik --- drivers/ata/libata-sff.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'drivers/ata/libata-sff.c') diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 714cb046b59..f93dc029dfd 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -2066,6 +2066,7 @@ static int ata_bus_softreset(struct ata_port *ap, unsigned int devmask, iowrite8(ap->ctl | ATA_SRST, ioaddr->ctl_addr); udelay(20); /* FIXME: flush */ iowrite8(ap->ctl, ioaddr->ctl_addr); + ap->last_ctl = ap->ctl; /* wait the port to become ready */ return ata_sff_wait_after_reset(&ap->link, devmask, deadline); @@ -2190,8 +2191,10 @@ void ata_sff_postreset(struct ata_link *link, unsigned int *classes) } /* set up device control */ - if (ap->ioaddr.ctl_addr) + if (ap->ioaddr.ctl_addr) { iowrite8(ap->ctl, ap->ioaddr.ctl_addr); + ap->last_ctl = ap->ctl; + } } EXPORT_SYMBOL_GPL(ata_sff_postreset); @@ -2534,6 +2537,7 @@ void ata_bus_reset(struct ata_port *ap) if (ap->flags & (ATA_FLAG_SATA_RESET | ATA_FLAG_SRST)) { /* set up device control for ATA_FLAG_SATA_RESET */ iowrite8(ap->ctl, ioaddr->ctl_addr); + ap->last_ctl = ap->ctl; } DPRINTK("EXIT\n"); -- cgit v1.2.3 From 3d47aa8e7e7b2aa09256590388aa8dddc79280f9 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Tue, 24 Mar 2009 10:23:19 +0000 Subject: [libata] Drain data on errors If the device is signalling that there is data to drain after an error we should read the bytes out and throw them away. Without this some devices and controllers get wedged and don't recover. Based on earlier work by Mark Lord Signed-off-by: Alan Cox Signed-off-by: Jeff Garzik --- drivers/ata/libata-sff.c | 45 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 43 insertions(+), 2 deletions(-) (limited to 'drivers/ata/libata-sff.c') diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index f93dc029dfd..9a10cb055ac 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -52,6 +52,7 @@ const struct ata_port_operations ata_sff_port_ops = { .softreset = ata_sff_softreset, .hardreset = sata_sff_hardreset, .postreset = ata_sff_postreset, + .drain_fifo = ata_sff_drain_fifo, .error_handler = ata_sff_error_handler, .post_internal_cmd = ata_sff_post_internal_cmd, @@ -2198,6 +2199,39 @@ void ata_sff_postreset(struct ata_link *link, unsigned int *classes) } EXPORT_SYMBOL_GPL(ata_sff_postreset); +/** + * ata_sff_drain_fifo - Stock FIFO drain logic for SFF controllers + * @qc: command + * + * Drain the FIFO and device of any stuck data following a command + * failing to complete. In some cases this is neccessary before a + * reset will recover the device. + * + */ + +void ata_sff_drain_fifo(struct ata_queued_cmd *qc) +{ + int count; + struct ata_port *ap; + + /* We only need to flush incoming data when a command was running */ + if (qc == NULL || qc->dma_dir == DMA_TO_DEVICE) + return; + + ap = qc->ap; + /* Drain up to 64K of data before we give up this recovery method */ + for (count = 0; (ap->ops->sff_check_status(ap) & ATA_DRQ) + && count < 32768; count++) + ioread16(ap->ioaddr.data_addr); + + /* Can become DEBUG later */ + if (count) + ata_port_printk(ap, KERN_DEBUG, + "drained %d bytes to clear DRQ.\n", count); + +} +EXPORT_SYMBOL_GPL(ata_sff_drain_fifo); + /** * ata_sff_error_handler - Stock error handler for BMDMA controller * @ap: port to handle error for @@ -2239,7 +2273,8 @@ void ata_sff_error_handler(struct ata_port *ap) * really a timeout event, adjust error mask and * cancel frozen state. */ - if (qc->err_mask == AC_ERR_TIMEOUT && (host_stat & ATA_DMA_ERR)) { + if (qc->err_mask == AC_ERR_TIMEOUT + && (host_stat & ATA_DMA_ERR)) { qc->err_mask = AC_ERR_HOST_BUS; thaw = 1; } @@ -2250,6 +2285,13 @@ void ata_sff_error_handler(struct ata_port *ap) ata_sff_sync(ap); /* FIXME: We don't need this */ ap->ops->sff_check_status(ap); ap->ops->sff_irq_clear(ap); + /* We *MUST* do FIFO draining before we issue a reset as several + * devices helpfully clear their internal state and will lock solid + * if we touch the data port post reset. Pass qc in case anyone wants + * to do different PIO/DMA recovery or has per command fixups + */ + if (ap->ops->drain_fifo) + ap->ops->drain_fifo(qc); spin_unlock_irqrestore(ap->lock, flags); @@ -2959,4 +3001,3 @@ out: EXPORT_SYMBOL_GPL(ata_pci_sff_init_one); #endif /* CONFIG_PCI */ - -- cgit v1.2.3 From c96f1732e25362d10ee7bcac1df8412a2e6b7d23 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Tue, 24 Mar 2009 10:23:46 +0000 Subject: [libata] Improve timeout handling On a timeout call a device specific handler early in the recovery so that we can complete and process successful commands which timed out due to IRQ loss or the like rather more elegantly. [Revised to exclude the timeout handling on a few devices that inherit from SFF but are not SFF enough to use the default timeout handler] Signed-off-by: Alan Cox Signed-off-by: Jeff Garzik --- drivers/ata/libata-sff.c | 46 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 45 insertions(+), 1 deletion(-) (limited to 'drivers/ata/libata-sff.c') diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 9a10cb055ac..8332e97a9de 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -65,6 +65,8 @@ const struct ata_port_operations ata_sff_port_ops = { .sff_irq_on = ata_sff_irq_on, .sff_irq_clear = ata_sff_irq_clear, + .lost_interrupt = ata_sff_lost_interrupt, + .port_start = ata_sff_port_start, }; EXPORT_SYMBOL_GPL(ata_sff_port_ops); @@ -1647,7 +1649,7 @@ EXPORT_SYMBOL_GPL(ata_sff_qc_fill_rtf); * RETURNS: * One if interrupt was handled, zero if not (shared irq). */ -inline unsigned int ata_sff_host_intr(struct ata_port *ap, +unsigned int ata_sff_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc) { struct ata_eh_info *ehi = &ap->link.eh_info; @@ -1775,6 +1777,48 @@ irqreturn_t ata_sff_interrupt(int irq, void *dev_instance) } EXPORT_SYMBOL_GPL(ata_sff_interrupt); +/** + * ata_sff_lost_interrupt - Check for an apparent lost interrupt + * @ap: port that appears to have timed out + * + * Called from the libata error handlers when the core code suspects + * an interrupt has been lost. If it has complete anything we can and + * then return. Interface must support altstatus for this faster + * recovery to occur. + * + * Locking: + * Caller holds host lock + */ + +void ata_sff_lost_interrupt(struct ata_port *ap) +{ + u8 status; + struct ata_queued_cmd *qc; + + /* Only one outstanding command per SFF channel */ + qc = ata_qc_from_tag(ap, ap->link.active_tag); + /* Check we have a live one.. */ + if (qc == NULL || !(qc->flags & ATA_QCFLAG_ACTIVE)) + return; + /* We cannot lose an interrupt on a polled command */ + if (qc->tf.flags & ATA_TFLAG_POLLING) + return; + /* See if the controller thinks it is still busy - if so the command + isn't a lost IRQ but is still in progress */ + status = ata_sff_altstatus(ap); + if (status & ATA_BUSY) + return; + + /* There was a command running, we are no longer busy and we have + no interrupt. */ + ata_port_printk(ap, KERN_WARNING, "lost interrupt (Status 0x%x)\n", + status); + /* Run the host interrupt logic as if the interrupt had not been + lost */ + ata_sff_host_intr(ap, qc); +} +EXPORT_SYMBOL_GPL(ata_sff_lost_interrupt); + /** * ata_sff_freeze - Freeze SFF controller port * @ap: port to freeze -- cgit v1.2.3