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<font size="-1">Hi Alistair,<br>
<br>
Applied all of the patches on top of 'v4.0-rc7', found this issue
during<br>
the boot itself <a class="moz-txt-link-freetext" href="http://pastebin.hursley.ibm.com/918">http://pastebin.hursley.ibm.com/918</a>.<br>
<br>
There are few compile warnings and minor comments.<br>
<br>
drivers/tty/hvc/hvc_opal.c: In function ‘hvc_opal_probe’:<br>
drivers/tty/hvc/hvc_opal.c:174:6: warning: unused variable ‘rc’
[-Wunused-variable]<br>
int rc; <br>
^ <br>
drivers/tty/hvc/hvc_opal.c: At top level:<br>
drivers/tty/hvc/hvc_opal.c:65:13: warning:
‘hvc_opal_event_registered’ defined but not used
[-Wunused-variable]<br>
static bool hvc_opal_event_registered;<br>
<br>
Regards,<br>
Neelesh.<br>
</font><br>
<div class="moz-cite-prefix">On 04/10/2015 01:54 PM, Alistair Popple
wrote:<br>
</div>
<blockquote
cite="mid:1428654294-9177-1-git-send-email-alistair@popple.id.au"
type="cite">
<pre wrap="">Whenever an interrupt is received for opal the linux kernel gets a
bitfield indicating certain events that have occurred and need handling
by the various device drivers. Currently this is handled using a
notifier interface where we call every device driver that has
registered to receive opal events.
This approach has several drawbacks. For example each driver has to do
its own checking to see if the event is relevant as well as event
masking. There is also no easy method of recording the number of times
we receive particular events.
This patch solves these issues by exposing opal events via the
standard interrupt APIs by adding a new interrupt chip and
domain. Drivers can then register for the appropriate events using
standard kernel calls such as irq_of_parse_and_map().
Signed-off-by: Alistair Popple <a class="moz-txt-link-rfc2396E" href="mailto:alistair@popple.id.au"><alistair@popple.id.au></a>
---
+static int __init opal_event_init(void)
+{
+ struct device_node *dn, *opal_node;
+ const __be32 *irqs;
+ int i, irqlen;
+
+ opal_node = of_find_node_by_path("/ibm,opal");
+ if (!opal_node) {
+ pr_warn("opal: Node not found\n");
+ return -ENODEV;
+ }
+
+ dn = of_find_compatible_node(NULL, NULL, "ibm,opal-event");
+
+ /* If dn is NULL it means the domain won't be linked to a DT
+ * node so therefore irq_of_parse_and_map(...) wont work. But
+ * that shouldn't be problem because if we're running a
+ * version of skiboot that doesn't have the dn then the
+ * devices won't have the correct properties and will have to
+ * fall back to the legacy method (opal_event_request(...))
+ * anyway. */
+ opal_event_irqchip.domain =
+ irq_domain_add_linear(dn, 64, &opal_event_domain_ops,</pre>
</blockquote>
<br>
<small>A macro would be better, which is maximum event bits we have.</small><br>
<br>
<blockquote
cite="mid:1428654294-9177-1-git-send-email-alistair@popple.id.au"
type="cite">
<pre wrap="">
+ &opal_event_irqchip);
+ if (IS_ERR(opal_event_irqchip.domain)) {
+ pr_warn("opal: Unable to create irq domain\n");
+ return PTR_ERR(opal_event_irqchip.domain);
+ }
+
+ /* Get interrupt property */
+ irqs = of_get_property(opal_node, "opal-interrupts", &irqlen);
+ opal_irq_count = irqs ? (irqlen / 4) : 0;</pre>
</blockquote>
<br>
<small>of_node_put()</small><br>
<font size="-1">Need to decrement the refcount of these nodes,
'opal_node' & 'dn' (if !NULL)<br>
</font><br>
<blockquote
cite="mid:1428654294-9177-1-git-send-email-alistair@popple.id.au"
type="cite">
<pre wrap="">
+ pr_debug("Found %d interrupts reserved for OPAL\n", opal_irq_count);
+
+ /* Install interrupt handlers */
+ opal_irqs = kcalloc(opal_irq_count, sizeof(unsigned int), GFP_KERNEL);</pre>
</blockquote>
<br>
<small>Safe to use 'sizeof(*opal_irqs)'</small><br>
<br>
<blockquote
cite="mid:1428654294-9177-1-git-send-email-alistair@popple.id.au"
type="cite">
<pre wrap="">
+ for (i = 0; irqs && i < opal_irq_count; i++, irqs++) {
+ unsigned int irq, virq;
+ int rc;
+
+ /* Get hardware and virtual IRQ */
+ irq = be32_to_cpup(irqs);
+ virq = irq_create_mapping(NULL, irq);
+ if (virq == NO_IRQ) {
+ pr_warn("Failed to map irq 0x%x\n", irq);
+ continue;
+ }
+
+ /* Install interrupt handler */
+ rc = request_irq(virq, opal_interrupt, 0, "opal", NULL);
+ if (rc) {
+ irq_dispose_mapping(virq);
+ pr_warn("Error %d requesting irq %d (0x%x)\n",
+ rc, virq, irq);
+ continue;
+ }
+
+ /* Cache IRQ */
+ opal_irqs[i] = virq;
+ }
+
+ return 0;
+}
+machine_core_initcall(powernv, opal_event_init);
+
</pre>
</blockquote>
<br>
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