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path: root/drivers/ata/libata-sff.c
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Diffstat (limited to 'drivers/ata/libata-sff.c')
-rw-r--r--drivers/ata/libata-sff.c91
1 files changed, 88 insertions, 3 deletions
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index f93dc029dfd..8332e97a9de 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,
@@ -64,6 +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);
@@ -1646,7 +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 +1778,48 @@ 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
*
@@ -2199,6 +2244,39 @@ 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 +2317,8 @@ 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 +2329,13 @@ 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 +3045,3 @@ out:
EXPORT_SYMBOL_GPL(ata_pci_sff_init_one);
#endif /* CONFIG_PCI */
-