[SPARC64]: Refine Sabre wsync logic.

It is only needed when there is a PCI-PCI bridge sitting between the device and the PCI host controller which is not a Simba APB bridge. Add logic to handle two special cases: 1) device behind EBUS, which sits on PCI 2) PCI controller interrupts Signed-off-by: David S. Miller <davem@davemloft.net>

[SPARC64]: Refine Sabre wsync logic.
It is only needed when there is a PCI-PCI bridge sitting between the device and the PCI host controller which is not a Simba APB bridge. Add logic to handle two special cases: 1) device behind EBUS, which sits on PCI 2) PCI controller interrupts Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller
1 parent 91d1ed1a6d
Showing 1 changed file with 27 additions and 8 deletions Side-by-side Diff
arch/sparc64/kernel/prom.c
@@ -539,23 +539,43 @@
 	((ino & 0x20) ? (SABRE_ICLR_SCSI + (((ino) & 0x1f) << 3)) :  \
 			(SABRE_ICLR_A_SLOT0 + (((ino) & 0x1f)<<3)))
  
-static int parent_is_sabre_or_simba(struct device_node *dp)
+static int sabre_device_needs_wsync(struct device_node *dp)
 {
+	struct device_node *parent = dp->parent;
 	char *parent_model, *parent_compat;
  
-	parent_model = of_get_property(dp->parent, "model", NULL);
+	/* This traversal up towards the root is meant to
+	 * handle two cases:
+	 *
+	 * 1) non-PCI bus sitting under PCI, such as 'ebus'
+	 * 2) the PCI controller interrupts themselves, which
+	 *    will use the sabre_irq_build but do not need
+	 *    the DMA synchronization handling
+	 */
+	while (parent) {
+		if (!strcmp(parent->type, "pci"))
+			break;
+		parent = parent->parent;
+	}
+
+	if (!parent)
+		return 0;
+
+	parent_model = of_get_property(parent,
+				       "model", NULL);
 	if (parent_model &&
 	    (!strcmp(parent_model, "SUNW,sabre") ||
 	     !strcmp(parent_model, "SUNW,simba")))
-		return 1;
+		return 0;
  
-	parent_compat = of_get_property(dp->parent, "compatible", NULL);
+	parent_compat = of_get_property(parent,
+					"compatible", NULL);
 	if (parent_compat &&
 	    (!strcmp(parent_compat, "pci108e,a000") ||
 	     !strcmp(parent_compat, "pci108e,a001")))
-		return 1;
+		return 0;
  
-	return 0;
+	return 1;
 }
  
 static unsigned int sabre_irq_build(struct device_node *dp,
@@ -602,8 +622,7 @@
 	 * is run.
 	 */
 	regs = of_get_property(dp, "reg", NULL);
-	if (regs &&
-	    !parent_is_sabre_or_simba(dp)) {
+	if (regs && sabre_device_needs_wsync(dp)) {
 		irq_install_pre_handler(virt_irq,
 					sabre_wsync_handler,
 					(void *) (long) regs->phys_hi,
...	...	@@ -539,23 +539,43 @@
539	539	((ino & 0x20) ? (SABRE_ICLR_SCSI + (((ino) & 0x1f) << 3)) : \
540	540	(SABRE_ICLR_A_SLOT0 + (((ino) & 0x1f)<<3)))
541	541
542		-static int parent_is_sabre_or_simba(struct device_node *dp)
	542	+static int sabre_device_needs_wsync(struct device_node *dp)
543	543	{
	544	+ struct device_node *parent = dp->parent;
544	545	char parent_model, parent_compat;
545	546
546		- parent_model = of_get_property(dp->parent, "model", NULL);
	547	+ /* This traversal up towards the root is meant to
	548	+ * handle two cases:
	549	+ *
	550	+ * 1) non-PCI bus sitting under PCI, such as 'ebus'
	551	+ * 2) the PCI controller interrupts themselves, which
	552	+ * will use the sabre_irq_build but do not need
	553	+ * the DMA synchronization handling
	554	+ */
	555	+ while (parent) {
	556	+ if (!strcmp(parent->type, "pci"))
	557	+ break;
	558	+ parent = parent->parent;
	559	+ }
	560	+
	561	+ if (!parent)
	562	+ return 0;
	563	+
	564	+ parent_model = of_get_property(parent,
	565	+ "model", NULL);
547	566	if (parent_model &&
548	567	(!strcmp(parent_model, "SUNW,sabre") \|\|
549	568	!strcmp(parent_model, "SUNW,simba")))
550		- return 1;
	569	+ return 0;
551	570
552		- parent_compat = of_get_property(dp->parent, "compatible", NULL);
	571	+ parent_compat = of_get_property(parent,
	572	+ "compatible", NULL);
553	573	if (parent_compat &&
554	574	(!strcmp(parent_compat, "pci108e,a000") \|\|
555	575	!strcmp(parent_compat, "pci108e,a001")))
556		- return 1;
	576	+ return 0;
557	577
558		- return 0;
	578	+ return 1;
559	579	}
560	580
561	581	static unsigned int sabre_irq_build(struct device_node *dp,
...	...	@@ -602,8 +622,7 @@
602	622	* is run.
603	623	*/
604	624	regs = of_get_property(dp, "reg", NULL);
605		- if (regs &&
606		- !parent_is_sabre_or_simba(dp)) {
	625	+ if (regs && sabre_device_needs_wsync(dp)) {
607	626	irq_install_pre_handler(virt_irq,
608	627	sabre_wsync_handler,
609	628	(void *) (long) regs->phys_hi,