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-rw-r--r--Documentation/DocBook/libata.tmpl47
-rw-r--r--drivers/scsi/libata-core.c31
-rw-r--r--include/linux/libata.h4
3 files changed, 76 insertions, 6 deletions
diff --git a/Documentation/DocBook/libata.tmpl b/Documentation/DocBook/libata.tmpl
index d260d92089a..5bcbb6ee3bc 100644
--- a/Documentation/DocBook/libata.tmpl
+++ b/Documentation/DocBook/libata.tmpl
@@ -120,14 +120,27 @@ void (*dev_config) (struct ata_port *, struct ata_device *);
<programlisting>
void (*set_piomode) (struct ata_port *, struct ata_device *);
void (*set_dmamode) (struct ata_port *, struct ata_device *);
-void (*post_set_mode) (struct ata_port *ap);
+void (*post_set_mode) (struct ata_port *);
+unsigned int (*mode_filter) (struct ata_port *, struct ata_device *, unsigned int);
</programlisting>
<para>
Hooks called prior to the issue of SET FEATURES - XFER MODE
- command. dev->pio_mode is guaranteed to be valid when
- ->set_piomode() is called, and dev->dma_mode is guaranteed to be
- valid when ->set_dmamode() is called. ->post_set_mode() is
+ command. The optional ->mode_filter() hook is called when libata
+ has built a mask of the possible modes. This is passed to the
+ ->mode_filter() function which should return a mask of valid modes
+ after filtering those unsuitable due to hardware limits. It is not
+ valid to use this interface to add modes.
+ </para>
+ <para>
+ dev->pio_mode and dev->dma_mode are guaranteed to be valid when
+ ->set_piomode() and when ->set_dmamode() is called. The timings for
+ any other drive sharing the cable will also be valid at this point.
+ That is the library records the decisions for the modes of each
+ drive on a channel before it attempts to set any of them.
+ </para>
+ <para>
+ ->post_set_mode() is
called unconditionally, after the SET FEATURES - XFER MODE
command completes successfully.
</para>
@@ -230,6 +243,32 @@ void (*dev_select)(struct ata_port *ap, unsigned int device);
</sect2>
+ <sect2><title>Private tuning method</title>
+ <programlisting>
+void (*set_mode) (struct ata_port *ap);
+ </programlisting>
+
+ <para>
+ By default libata performs drive and controller tuning in
+ accordance with the ATA timing rules and also applies blacklists
+ and cable limits. Some controllers need special handling and have
+ custom tuning rules, typically raid controllers that use ATA
+ commands but do not actually do drive timing.
+ </para>
+
+ <warning>
+ <para>
+ This hook should not be used to replace the standard controller
+ tuning logic when a controller has quirks. Replacing the default
+ tuning logic in that case would bypass handling for drive and
+ bridge quirks that may be important to data reliability. If a
+ controller needs to filter the mode selection it should use the
+ mode_filter hook instead.
+ </para>
+ </warning>
+
+ </sect2>
+
<sect2><title>Reset ATA bus</title>
<programlisting>
void (*phy_reset) (struct ata_port *ap);
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 41659448a20..b1ddf40533b 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1818,7 +1818,7 @@ static void ata_host_set_dma(struct ata_port *ap)
*/
static void ata_set_mode(struct ata_port *ap)
{
- int i, rc;
+ int i, rc, used_dma = 0;
/* step 1: calculate xfer_mask */
for (i = 0; i < ATA_MAX_DEVICES; i++) {
@@ -1836,6 +1836,9 @@ static void ata_set_mode(struct ata_port *ap)
dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
dev->pio_mode = ata_xfer_mask2mode(pio_mask);
dev->dma_mode = ata_xfer_mask2mode(dma_mask);
+
+ if (dev->dma_mode)
+ used_dma = 1;
}
/* step 2: always set host PIO timings */
@@ -1857,6 +1860,17 @@ static void ata_set_mode(struct ata_port *ap)
goto err_out;
}
+ /*
+ * Record simplex status. If we selected DMA then the other
+ * host channels are not permitted to do so.
+ */
+
+ if (used_dma && (ap->host_set->flags & ATA_HOST_SIMPLEX))
+ ap->host_set->simplex_claimed = 1;
+
+ /*
+ * Chip specific finalisation
+ */
if (ap->ops->post_set_mode)
ap->ops->post_set_mode(ap);
@@ -2646,13 +2660,14 @@ static int ata_dma_blacklisted(const struct ata_device *dev)
*/
static void ata_dev_xfermask(struct ata_port *ap, struct ata_device *dev)
{
+ struct ata_host_set *hs = ap->host_set;
unsigned long xfer_mask;
int i;
xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
ap->udma_mask);
- /* use port-wide xfermask for now */
+ /* FIXME: Use port-wide xfermask for now */
for (i = 0; i < ATA_MAX_DEVICES; i++) {
struct ata_device *d = &ap->device[i];
if (!ata_dev_present(d))
@@ -2662,12 +2677,23 @@ static void ata_dev_xfermask(struct ata_port *ap, struct ata_device *dev)
xfer_mask &= ata_id_xfermask(d->id);
if (ata_dma_blacklisted(d))
xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
+ /* Apply cable rule here. Don't apply it early because when
+ we handle hot plug the cable type can itself change */
+ if (ap->cbl == ATA_CBL_PATA40)
+ xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
}
if (ata_dma_blacklisted(dev))
printk(KERN_WARNING "ata%u: dev %u is on DMA blacklist, "
"disabling DMA\n", ap->id, dev->devno);
+ if (hs->flags & ATA_HOST_SIMPLEX) {
+ if (hs->simplex_claimed)
+ xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
+ }
+ if (ap->ops->mode_filter)
+ xfer_mask = ap->ops->mode_filter(ap, dev, xfer_mask);
+
ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
&dev->udma_mask);
}
@@ -4531,6 +4557,7 @@ int ata_device_add(const struct ata_probe_ent *ent)
host_set->mmio_base = ent->mmio_base;
host_set->private_data = ent->private_data;
host_set->ops = ent->port_ops;
+ host_set->flags = ent->host_set_flags;
/* register each port bound to this device */
for (i = 0; i < ent->n_ports; i++) {
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6a9316cbb70..0d61357604d 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -294,6 +294,9 @@ struct ata_host_set {
unsigned int n_ports;
void *private_data;
const struct ata_port_operations *ops;
+ unsigned long flags;
+ int simplex_claimed; /* Keep seperate in case we
+ ever need to do this locked */
struct ata_port * ports[0];
};
@@ -423,6 +426,7 @@ struct ata_port_operations {
void (*set_piomode) (struct ata_port *, struct ata_device *);
void (*set_dmamode) (struct ata_port *, struct ata_device *);
+ unsigned long (*mode_filter) (const struct ata_port *, struct ata_device *, unsigned long);
void (*tf_load) (struct ata_port *ap, const struct ata_taskfile *tf);
void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf);