[PATCH 1/1] [libata/BF54x]: Fix bug - Implement bfin ata interrupt handler to avoid "irq 68 nobody cared" (v2)

From: Bryan Wu
Date: Fri Apr 25 2008 - 05:20:25 EST


From: Sonic Zhang <sonic.zhang@xxxxxxxxxx>

Return IRQ_HANDLED when bfin ata device is busy.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3513

v1-v2:
- fold api breakage fixing patch together.
- mark 'static', not 'inline'.

Signed-off-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx>
Signed-off-by: Bryan Wu <cooloney@xxxxxxxxxx>
---
drivers/ata/pata_bf54x.c | 124 ++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 120 insertions(+), 4 deletions(-)

diff --git a/drivers/ata/pata_bf54x.c b/drivers/ata/pata_bf54x.c
index f334ba5..54473b3 100644
--- a/drivers/ata/pata_bf54x.c
+++ b/drivers/ata/pata_bf54x.c
@@ -1272,8 +1272,8 @@ static void bfin_freeze(struct ata_port *ap)

void bfin_thaw(struct ata_port *ap)
{
+ dev_dbg(ap->dev, "in atapi dma thaw\n");
bfin_check_status(ap);
- bfin_irq_clear(ap);
bfin_irq_on(ap);
}

@@ -1339,13 +1339,130 @@ static int bfin_port_start(struct ata_port *ap)
return 0;
}

+static unsigned int bfin_ata_host_intr(struct ata_port *ap,
+ struct ata_queued_cmd *qc)
+{
+ struct ata_eh_info *ehi = &ap->link.eh_info;
+ u8 status, host_stat = 0;
+
+ VPRINTK("ata%u: protocol %d task_state %d\n",
+ ap->print_id, qc->tf.protocol, ap->hsm_task_state);
+
+ /* Check whether we are expecting interrupt in this state */
+ 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 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 == ATAPI_PROT_DMA) {
+ /* check status of DMA engine */
+ host_stat = ap->ops->bmdma_status(ap);
+ VPRINTK("ata%u: host_stat 0x%X\n",
+ ap->print_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);
+
+ if (unlikely(host_stat & ATA_DMA_ERR)) {
+ /* error when transfering data to/from memory */
+ qc->err_mask |= AC_ERR_HOST_BUS;
+ ap->hsm_task_state = HSM_ST_ERR;
+ }
+ }
+ break;
+ case HSM_ST:
+ break;
+ default:
+ goto idle_irq;
+ }
+
+ /* check altstatus */
+ status = ap->ops->sff_check_altstatus(ap);
+ if (status & ATA_BUSY)
+ goto busy_ata;
+
+ /* check main status, clearing INTRQ */
+ status = ap->ops->sff_check_status(ap);
+ if (unlikely(status & ATA_BUSY))
+ goto busy_ata;
+
+ /* ack bmdma irq events */
+ ap->ops->sff_irq_clear(ap);
+
+ ata_sff_hsm_move(ap, qc, status, 0);
+
+ if (unlikely(qc->err_mask) && (qc->tf.protocol == ATA_PROT_DMA ||
+ qc->tf.protocol == ATAPI_PROT_DMA))
+ ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
+
+busy_ata:
+ return 1; /* irq handled */
+
+idle_irq:
+ ap->stats.idle_irq++;
+
+#ifdef ATA_IRQ_TRAP
+ if ((ap->stats.idle_irq % 1000) == 0) {
+ ap->ops->irq_ack(ap, 0); /* debug trap */
+ ata_port_printk(ap, KERN_WARNING, "irq trap\n");
+ return 1;
+ }
+#endif
+ return 0; /* irq not handled */
+}
+
+static irqreturn_t bfin_ata_interrupt(int irq, void *dev_instance)
+{
+ struct ata_host *host = dev_instance;
+ unsigned int i;
+ unsigned int handled = 0;
+ unsigned long flags;
+
+ /* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
+ spin_lock_irqsave(&host->lock, flags);
+
+ for (i = 0; i < host->n_ports; i++) {
+ struct ata_port *ap;
+
+ ap = host->ports[i];
+ if (ap &&
+ !(ap->flags & ATA_FLAG_DISABLED)) {
+ struct ata_queued_cmd *qc;
+
+ qc = ata_qc_from_tag(ap, ap->link.active_tag);
+ if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING)) &&
+ (qc->flags & ATA_QCFLAG_ACTIVE))
+ handled |= bfin_ata_host_intr(ap, qc);
+ }
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ return IRQ_RETVAL(handled);
+}
+
+
static struct scsi_host_template bfin_sht = {
ATA_BASE_SHT(DRV_NAME),
.sg_tablesize = SG_NONE,
.dma_boundary = ATA_DMA_BOUNDARY,
};

-static const struct ata_port_operations bfin_pata_ops = {
+static struct ata_port_operations bfin_pata_ops = {
.inherits = &ata_sff_port_ops,

.set_piomode = bfin_set_piomode,
@@ -1370,7 +1487,6 @@ static const struct ata_port_operations bfin_pata_ops = {
.thaw = bfin_thaw,
.softreset = bfin_softreset,
.postreset = bfin_postreset,
- .post_internal_cmd = bfin_bmdma_stop,

.sff_irq_clear = bfin_irq_clear,
.sff_irq_on = bfin_irq_on,
@@ -1507,7 +1623,7 @@ static int __devinit bfin_atapi_probe(struct platform_device *pdev)
}

if (ata_host_activate(host, platform_get_irq(pdev, 0),
- ata_sff_interrupt, IRQF_SHARED, &bfin_sht) != 0) {
+ bfin_ata_interrupt, IRQF_SHARED, &bfin_sht) != 0) {
peripheral_free_list(atapi_io_port);
dev_err(&pdev->dev, "Fail to attach ATAPI device\n");
return -ENODEV;
--
1.5.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/