<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 *);
-unsigned int (*mode_filter) (struct ata_port *, struct ata_device *, unsigned int);
+void (*post_set_mode) (struct ata_port *ap);
</programlisting>
<para>
Hooks called prior to the issue of SET FEATURES - XFER MODE
- 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
+ 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
called unconditionally, after the SET FEATURES - XFER MODE
command completes successfully.
</para>
</sect2>
- <sect2><title>PIO data read/write</title>
- <programlisting>
-void (*data_xfer) (struct ata_device *, unsigned char *, unsigned int, int);
- </programlisting>
-
- <para>
-All bmdma-style drivers must implement this hook. This is the low-level
-operation that actually copies the data bytes during a PIO data
-transfer.
-Typically the driver
-will choose one of ata_pio_data_xfer_noirq(), ata_pio_data_xfer(), or
-ata_mmio_data_xfer().
- </para>
-
- </sect2>
-
<sect2><title>ATA command execute</title>
<programlisting>
void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
<programlisting>
u8 (*check_status)(struct ata_port *ap);
u8 (*check_altstatus)(struct ata_port *ap);
+u8 (*check_err)(struct ata_port *ap);
</programlisting>
<para>
- Reads the Status/AltStatus ATA shadow register from
+ Reads the Status/AltStatus/Error ATA shadow register from
hardware. On some hardware, reading the Status register has
the side effect of clearing the interrupt condition.
Most drivers for taskfile-based hardware use
</sect2>
- <sect2><title>Private tuning method</title>
+ <sect2><title>Reset ATA bus</title>
<programlisting>
-void (*set_mode) (struct ata_port *ap);
+void (*phy_reset) (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.
+ The very first step in the probe phase. Actions vary depending
+ on the bus type, typically. After waking up the device and probing
+ for device presence (PATA and SATA), typically a soft reset
+ (SRST) will be performed. Drivers typically use the helper
+ functions ata_bus_reset() or sata_phy_reset() for this hook.
+ Many SATA drivers use sata_phy_reset() or call it from within
+ their own phy_reset() functions.
</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>Control PCI IDE BMDMA engine</title>
</sect2>
- <sect2><title>Exception and probe handling (EH)</title>
+ <sect2><title>Timeout (error) handling</title>
<programlisting>
void (*eng_timeout) (struct ata_port *ap);
-void (*phy_reset) (struct ata_port *ap);
- </programlisting>
-
- <para>
-Deprecated. Use ->error_handler() instead.
- </para>
-
- <programlisting>
-void (*freeze) (struct ata_port *ap);
-void (*thaw) (struct ata_port *ap);
- </programlisting>
-
- <para>
-ata_port_freeze() is called when HSM violations or some other
-condition disrupts normal operation of the port. A frozen port
-is not allowed to perform any operation until the port is
-thawed, which usually follows a successful reset.
- </para>
-
- <para>
-The optional ->freeze() callback can be used for freezing the port
-hardware-wise (e.g. mask interrupt and stop DMA engine). If a
-port cannot be frozen hardware-wise, the interrupt handler
-must ack and clear interrupts unconditionally while the port
-is frozen.
- </para>
- <para>
-The optional ->thaw() callback is called to perform the opposite of ->freeze():
-prepare the port for normal operation once again. Unmask interrupts,
-start DMA engine, etc.
- </para>
-
- <programlisting>
-void (*error_handler) (struct ata_port *ap);
- </programlisting>
-
- <para>
-->error_handler() is a driver's hook into probe, hotplug, and recovery
-and other exceptional conditions. The primary responsibility of an
-implementation is to call ata_do_eh() or ata_bmdma_drive_eh() with a set
-of EH hooks as arguments:
- </para>
-
- <para>
-'prereset' hook (may be NULL) is called during an EH reset, before any other actions
-are taken.
- </para>
-
- <para>
-'postreset' hook (may be NULL) is called after the EH reset is performed. Based on
-existing conditions, severity of the problem, and hardware capabilities,
- </para>
-
- <para>
-Either 'softreset' (may be NULL) or 'hardreset' (may be NULL) will be
-called to perform the low-level EH reset.
- </para>
-
- <programlisting>
-void (*post_internal_cmd) (struct ata_queued_cmd *qc);
</programlisting>
<para>
-Perform any hardware-specific actions necessary to finish processing
-after executing a probe-time or EH-time command via ata_exec_internal().
+This is a high level error handling function, called from the
+error handling thread, when a command times out. Most newer
+hardware will implement its own error handling code here. IDE BMDMA
+drivers may use the helper function ata_eng_timeout().
</para>
</sect2>
<sect1><title>ata_scsi_error()</title>
<para>
- ata_scsi_error() is the current transportt->eh_strategy_handler()
+ ata_scsi_error() is the current hostt->eh_strategy_handler()
for libata. As discussed above, this will be entered in two
cases - timeout and ATAPI error completion. This function
calls low level libata driver's eng_timeout() callback, the
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