genirq: Update DocBook comments

Fix some parts to match the actual code.

[ tglx: Resolved the FIXMEs Gerd put in ]

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/%3C1302426113-13808-3-git-send-email-geert%40linux-m68k.org%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-doc@vger.kernel.org
This commit is contained in:
Geert Uytterhoeven 2011-04-10 11:01:53 +02:00 committed by Thomas Gleixner
parent 0911f124bf
commit ee430599bf

View file

@ -191,8 +191,8 @@
<para>
Whenever an interrupt triggers, the lowlevel arch code calls into
the generic interrupt code by calling desc->handle_irq().
This highlevel IRQ handling function only uses desc->chip primitives
referenced by the assigned chip descriptor structure.
This highlevel IRQ handling function only uses desc->irq_data.chip
primitives referenced by the assigned chip descriptor structure.
</para>
</sect1>
<sect1 id="Highlevel_Driver_API">
@ -206,11 +206,11 @@
<listitem><para>enable_irq()</para></listitem>
<listitem><para>disable_irq_nosync() (SMP only)</para></listitem>
<listitem><para>synchronize_irq() (SMP only)</para></listitem>
<listitem><para>set_irq_type()</para></listitem>
<listitem><para>set_irq_wake()</para></listitem>
<listitem><para>set_irq_data()</para></listitem>
<listitem><para>set_irq_chip()</para></listitem>
<listitem><para>set_irq_chip_data()</para></listitem>
<listitem><para>irq_set_irq_type()</para></listitem>
<listitem><para>irq_set_irq_wake()</para></listitem>
<listitem><para>irq_set_handler_data()</para></listitem>
<listitem><para>irq_set_chip()</para></listitem>
<listitem><para>irq_set_chip_data()</para></listitem>
</itemizedlist>
See the autogenerated function documentation for details.
</para>
@ -225,6 +225,8 @@
<listitem><para>handle_fasteoi_irq</para></listitem>
<listitem><para>handle_simple_irq</para></listitem>
<listitem><para>handle_percpu_irq</para></listitem>
<listitem><para>handle_edge_eoi_irq</para></listitem>
<listitem><para>handle_bad_irq</para></listitem>
</itemizedlist>
The interrupt flow handlers (either predefined or architecture
specific) are assigned to specific interrupts by the architecture
@ -241,13 +243,13 @@
<programlisting>
default_enable(struct irq_data *data)
{
desc->chip->irq_unmask(data);
desc->irq_data.chip->irq_unmask(data);
}
default_disable(struct irq_data *data)
{
if (!delay_disable(data))
desc->chip->irq_mask(data);
desc->irq_data.chip->irq_mask(data);
}
default_ack(struct irq_data *data)
@ -284,9 +286,9 @@ noop(struct irq_data *data))
<para>
The following control flow is implemented (simplified excerpt):
<programlisting>
desc->chip->irq_mask();
handle_IRQ_event(desc->action);
desc->chip->irq_unmask();
desc->irq_data.chip->irq_mask_ack();
handle_irq_event(desc->action);
desc->irq_data.chip->irq_unmask();
</programlisting>
</para>
</sect3>
@ -300,8 +302,8 @@ desc->chip->irq_unmask();
<para>
The following control flow is implemented (simplified excerpt):
<programlisting>
handle_IRQ_event(desc->action);
desc->chip->irq_eoi();
handle_irq_event(desc->action);
desc->irq_data.chip->irq_eoi();
</programlisting>
</para>
</sect3>
@ -315,17 +317,17 @@ desc->chip->irq_eoi();
The following control flow is implemented (simplified excerpt):
<programlisting>
if (desc->status &amp; running) {
desc->chip->irq_mask();
desc->irq_data.chip->irq_mask_ack();
desc->status |= pending | masked;
return;
}
desc->chip->irq_ack();
desc->irq_data.chip->irq_ack();
desc->status |= running;
do {
if (desc->status &amp; masked)
desc->chip->irq_unmask();
desc->irq_data.chip->irq_unmask();
desc->status &amp;= ~pending;
handle_IRQ_event(desc->action);
handle_irq_event(desc->action);
} while (status &amp; pending);
desc->status &amp;= ~running;
</programlisting>
@ -344,7 +346,7 @@ desc->status &amp;= ~running;
<para>
The following control flow is implemented (simplified excerpt):
<programlisting>
handle_IRQ_event(desc->action);
handle_irq_event(desc->action);
</programlisting>
</para>
</sect3>
@ -362,12 +364,29 @@ handle_IRQ_event(desc->action);
<para>
The following control flow is implemented (simplified excerpt):
<programlisting>
handle_IRQ_event(desc->action);
if (desc->chip->irq_eoi)
desc->chip->irq_eoi();
if (desc->irq_data.chip->irq_ack)
desc->irq_data.chip->irq_ack();
handle_irq_event(desc->action);
if (desc->irq_data.chip->irq_eoi)
desc->irq_data.chip->irq_eoi();
</programlisting>
</para>
</sect3>
<sect3 id="EOI_Edge_IRQ_flow_handler">
<title>EOI Edge IRQ flow handler</title>
<para>
handle_edge_eoi_irq provides an abnomination of the edge
handler which is solely used to tame a badly wreckaged
irq controller on powerpc/cell.
</para>
</sect3>
<sect3 id="BAD_IRQ_flow_handler">
<title>Bad IRQ flow handler</title>
<para>
handle_bad_irq is used for spurious interrupts which
have no real handler assigned..
</para>
</sect3>
</sect2>
<sect2 id="Quirks_and_optimizations">
<title>Quirks and optimizations</title>
@ -410,6 +429,7 @@ if (desc->chip->irq_eoi)
<listitem><para>irq_mask_ack() - Optional, recommended for performance</para></listitem>
<listitem><para>irq_mask()</para></listitem>
<listitem><para>irq_unmask()</para></listitem>
<listitem><para>irq_eoi() - Optional, required for eoi flow handlers</para></listitem>
<listitem><para>irq_retrigger() - Optional</para></listitem>
<listitem><para>irq_set_type() - Optional</para></listitem>
<listitem><para>irq_set_wake() - Optional</para></listitem>
@ -424,32 +444,24 @@ if (desc->chip->irq_eoi)
<chapter id="doirq">
<title>__do_IRQ entry point</title>
<para>
The original implementation __do_IRQ() is an alternative entry
point for all types of interrupts.
The original implementation __do_IRQ() was an alternative entry
point for all types of interrupts. It not longer exists.
</para>
<para>
This handler turned out to be not suitable for all
interrupt hardware and was therefore reimplemented with split
functionality for egde/level/simple/percpu interrupts. This is not
functionality for edge/level/simple/percpu interrupts. This is not
only a functional optimization. It also shortens code paths for
interrupts.
</para>
<para>
To make use of the split implementation, replace the call to
__do_IRQ by a call to desc->handle_irq() and associate
the appropriate handler function to desc->handle_irq().
In most cases the generic handler implementations should
be sufficient.
</para>
</chapter>
<chapter id="locking">
<title>Locking on SMP</title>
<para>
The locking of chip registers is up to the architecture that
defines the chip primitives. There is a chip->lock field that can be used
for serialization, but the generic layer does not touch it. The per-irq
structure is protected via desc->lock, by the generic layer.
defines the chip primitives. The per-irq structure is
protected via desc->lock, by the generic layer.
</para>
</chapter>
<chapter id="structs">