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authorPekka Enberg <penberg@kernel.org>2010-10-24 19:57:05 +0300
committerPekka Enberg <penberg@kernel.org>2010-10-24 19:57:05 +0300
commit6d4121f6c20a0e86231d52f535f1c82423b3326f (patch)
tree5c235cac699ca86b504850aa663ddadde0455a61 /Documentation/DocBook/genericirq.tmpl
parent92a5bbc11ff2442a54b2f1d313088c245828ef4e (diff)
parent35da7a307c535f9c2929cae277f3df425c9f9b1e (diff)
Merge branch 'master' into for-linus
Conflicts: include/linux/percpu.h mm/percpu.c
Diffstat (limited to 'Documentation/DocBook/genericirq.tmpl')
-rw-r--r--Documentation/DocBook/genericirq.tmpl84
1 files changed, 52 insertions, 32 deletions
diff --git a/Documentation/DocBook/genericirq.tmpl b/Documentation/DocBook/genericirq.tmpl
index 1448b33fd222..fb10fd08c05c 100644
--- a/Documentation/DocBook/genericirq.tmpl
+++ b/Documentation/DocBook/genericirq.tmpl
@@ -28,7 +28,7 @@
</authorgroup>
<copyright>
- <year>2005-2006</year>
+ <year>2005-2010</year>
<holder>Thomas Gleixner</holder>
</copyright>
<copyright>
@@ -100,6 +100,10 @@
<listitem><para>Edge type</para></listitem>
<listitem><para>Simple type</para></listitem>
</itemizedlist>
+ During the implementation we identified another type:
+ <itemizedlist>
+ <listitem><para>Fast EOI type</para></listitem>
+ </itemizedlist>
In the SMP world of the __do_IRQ() super-handler another type
was identified:
<itemizedlist>
@@ -153,6 +157,7 @@
is still available. This leads to a kind of duality for the time
being. Over time the new model should be used in more and more
architectures, as it enables smaller and cleaner IRQ subsystems.
+ It's deprecated for three years now and about to be removed.
</para>
</chapter>
<chapter id="bugs">
@@ -217,6 +222,7 @@
<itemizedlist>
<listitem><para>handle_level_irq</para></listitem>
<listitem><para>handle_edge_irq</para></listitem>
+ <listitem><para>handle_fasteoi_irq</para></listitem>
<listitem><para>handle_simple_irq</para></listitem>
<listitem><para>handle_percpu_irq</para></listitem>
</itemizedlist>
@@ -233,33 +239,33 @@
are used by the default flow implementations.
The following helper functions are implemented (simplified excerpt):
<programlisting>
-default_enable(irq)
+default_enable(struct irq_data *data)
{
- desc->chip->unmask(irq);
+ desc->chip->irq_unmask(data);
}
-default_disable(irq)
+default_disable(struct irq_data *data)
{
- if (!delay_disable(irq))
- desc->chip->mask(irq);
+ if (!delay_disable(data))
+ desc->chip->irq_mask(data);
}
-default_ack(irq)
+default_ack(struct irq_data *data)
{
- chip->ack(irq);
+ chip->irq_ack(data);
}
-default_mask_ack(irq)
+default_mask_ack(struct irq_data *data)
{
- if (chip->mask_ack) {
- chip->mask_ack(irq);
+ if (chip->irq_mask_ack) {
+ chip->irq_mask_ack(data);
} else {
- chip->mask(irq);
- chip->ack(irq);
+ chip->irq_mask(data);
+ chip->irq_ack(data);
}
}
-noop(irq)
+noop(struct irq_data *data))
{
}
@@ -278,12 +284,27 @@ noop(irq)
<para>
The following control flow is implemented (simplified excerpt):
<programlisting>
-desc->chip->start();
+desc->chip->irq_mask();
handle_IRQ_event(desc->action);
-desc->chip->end();
+desc->chip->irq_unmask();
</programlisting>
</para>
- </sect3>
+ </sect3>
+ <sect3 id="Default_FASTEOI_IRQ_flow_handler">
+ <title>Default Fast EOI IRQ flow handler</title>
+ <para>
+ handle_fasteoi_irq provides a generic implementation
+ for interrupts, which only need an EOI at the end of
+ the handler
+ </para>
+ <para>
+ The following control flow is implemented (simplified excerpt):
+ <programlisting>
+handle_IRQ_event(desc->action);
+desc->chip->irq_eoi();
+ </programlisting>
+ </para>
+ </sect3>
<sect3 id="Default_Edge_IRQ_flow_handler">
<title>Default Edge IRQ flow handler</title>
<para>
@@ -294,20 +315,19 @@ desc->chip->end();
The following control flow is implemented (simplified excerpt):
<programlisting>
if (desc->status &amp; running) {
- desc->chip->hold();
+ desc->chip->irq_mask();
desc->status |= pending | masked;
return;
}
-desc->chip->start();
+desc->chip->irq_ack();
desc->status |= running;
do {
if (desc->status &amp; masked)
- desc->chip->enable();
+ desc->chip->irq_unmask();
desc->status &amp;= ~pending;
handle_IRQ_event(desc->action);
} while (status &amp; pending);
desc->status &amp;= ~running;
-desc->chip->end();
</programlisting>
</para>
</sect3>
@@ -342,9 +362,9 @@ handle_IRQ_event(desc->action);
<para>
The following control flow is implemented (simplified excerpt):
<programlisting>
-desc->chip->start();
handle_IRQ_event(desc->action);
-desc->chip->end();
+if (desc->chip->irq_eoi)
+ desc->chip->irq_eoi();
</programlisting>
</para>
</sect3>
@@ -375,8 +395,7 @@ desc->chip->end();
mechanism. (It's necessary to enable CONFIG_HARDIRQS_SW_RESEND when
you want to use the delayed interrupt disable feature and your
hardware is not capable of retriggering an interrupt.)
- The delayed interrupt disable can be runtime enabled, per interrupt,
- by setting the IRQ_DELAYED_DISABLE flag in the irq_desc status field.
+ The delayed interrupt disable is not configurable.
</para>
</sect2>
</sect1>
@@ -387,13 +406,13 @@ desc->chip->end();
contains all the direct chip relevant functions, which
can be utilized by the irq flow implementations.
<itemizedlist>
- <listitem><para>ack()</para></listitem>
- <listitem><para>mask_ack() - Optional, recommended for performance</para></listitem>
- <listitem><para>mask()</para></listitem>
- <listitem><para>unmask()</para></listitem>
- <listitem><para>retrigger() - Optional</para></listitem>
- <listitem><para>set_type() - Optional</para></listitem>
- <listitem><para>set_wake() - Optional</para></listitem>
+ <listitem><para>irq_ack()</para></listitem>
+ <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_retrigger() - Optional</para></listitem>
+ <listitem><para>irq_set_type() - Optional</para></listitem>
+ <listitem><para>irq_set_wake() - Optional</para></listitem>
</itemizedlist>
These primitives are strictly intended to mean what they say: ack means
ACK, masking means masking of an IRQ line, etc. It is up to the flow
@@ -458,6 +477,7 @@ desc->chip->end();
<para>
This chapter contains the autogenerated documentation of the internal functions.
</para>
+!Ikernel/irq/irqdesc.c
!Ikernel/irq/handle.c
!Ikernel/irq/chip.c
</chapter>