Fix PCI IRQ probing for some bridging situations.

Use PCI_SLOT instead of hard-coded shift.

arch/sparc64/kernel/pci_common.c

@@ -583,21 +583,45 @@ static int __init pci_intmap_match(struct pci_dev *pdev, unsigned int *interrupt
 	/* If we are underneath a PCI bridge, use PROM register
 	 * property of the parent bridge which is closest to
 	 * the PBM.
+	 *
+	 * However if that parent bridge has interrupt map/mask
+	 * properties of it's own we use the PROM register property
+	 * of the next child device on the path to PDEV.
+	 *
+	 * In detail the two cases are (note that the 'X' below is the
+	 * 'next child on the path to PDEV' mentioned above):
+	 *
+	 * 1) PBM --> PCI bus lacking int{map,mask} --> X ... PDEV
+	 *
+	 *    Here we use regs of 'PCI bus' device.
+	 *
+	 * 2) PBM --> PCI bus with int{map,mask} --> X ... PDEV
+	 *
+	 *    Here we use regs of 'X'.  Note that X can be PDEV.
 	 */
 	if (pdev->bus->number != pbm->pci_first_busno) {
-		struct pcidev_cookie *bus_pcp;
-		struct pci_dev *pwalk;
-		int offset, plen;
+		struct pcidev_cookie *bus_pcp, *regs_pcp;
+		struct pci_dev *bus_dev, *regs_dev;
+		int plen;
+
+		bus_dev = pdev->bus->self;
+		regs_dev = pdev;
 
-		pwalk = pdev->bus->self;
-		while (pwalk->bus &&
-		       pwalk->bus->number != pbm->pci_first_busno)
-			pwalk = pwalk->bus->self;
+		while (bus_dev->bus &&
+		       bus_dev->bus->number != pbm->pci_first_busno) {
+			regs_dev = bus_dev;
+			bus_dev = bus_dev->bus->self;
+		}
+
+		regs_pcp = regs_dev->sysdata;
+		pregs = regs_pcp->prom_regs;
 
-		bus_pcp = pwalk->sysdata;
+		bus_pcp = bus_dev->sysdata;
 
 		/* But if the PCI bridge has it's own interrupt map
-		 * and mask properties, use that and the device regs.
+		 * and mask properties, use that and the regs of the
+		 * PCI entity at the next level down on the path to the
+		 * device.
 		 */
 		plen = prom_getproperty(bus_pcp->prom_node, "interrupt-map",
 					(char *) &bridge_local_intmap[0],
@@ -605,38 +629,21 @@ static int __init pci_intmap_match(struct pci_dev *pdev, unsigned int *interrupt
 		if (plen != -1) {
 			intmap = &bridge_local_intmap[0];
 			num_intmap = plen / sizeof(struct linux_prom_pci_intmap);
-			plen = prom_getproperty(bus_pcp->prom_node, "interrupt-map-mask",
+			plen = prom_getproperty(bus_pcp->prom_node,
+						"interrupt-map-mask",
 						(char *) &bridge_local_intmask,
 						sizeof(bridge_local_intmask));
 			if (plen == -1) {
-				prom_printf("pbm_intmap_match: Bridge has intmap but "
-					    "no intmask.\n");
-				prom_halt();
+				printk("pci_intmap_match: Warning! Bridge has intmap "
+				       "but no intmask.\n");
+				printk("pci_intmap_match: Trying to recover.\n");
+				return 0;
 			}
-			goto check_intmap;
-		}
-
-		pregs = bus_pcp->prom_regs;
-
-		offset = prom_getint(dev_pcp->prom_node,
-				     "fcode-rom-offset");
-
-		/* Did PROM know better and assign an interrupt other
-		 * than #INTA to the device? - We test here for presence of
-		 * FCODE on the card, in this case we assume PROM has set
-		 * correct 'interrupts' property, unless it is quadhme.
-		 */
-		if (offset == -1 ||
-		    !strcmp(dev_pcp->prom_name, "SUNW,qfe") ||
-		    !strcmp(dev_pcp->prom_name, "qfe")) {
-			/*
-			 * No, use low slot number bits of child as IRQ line.
-			 */
-			*interrupt = ((*interrupt - 1 + PCI_SLOT(pdev->devfn)) & 3) + 1;
+		} else {
+			pregs = bus_pcp->prom_regs;
 		}
 	}
 
-check_intmap:
 	hi   = pregs->phys_hi & intmask->phys_hi;
 	mid  = pregs->phys_mid & intmask->phys_mid;
 	lo   = pregs->phys_lo & intmask->phys_lo;
@@ -652,12 +659,22 @@ static int __init pci_intmap_match(struct pci_dev *pdev, unsigned int *interrupt
 		}
 	}
 
-	prom_printf("pbm_intmap_match: bus %02x, devfn %02x: ",
+	/* Print it both to OBP console and kernel one so that if bootup
+	 * hangs here the user has the information to report.
+	 */
+	prom_printf("pci_intmap_match: bus %02x, devfn %02x: ",
 		    pdev->bus->number, pdev->devfn);
 	prom_printf("IRQ [%08x.%08x.%08x.%08x] not found in interrupt-map\n",
 		    pregs->phys_hi, pregs->phys_mid, pregs->phys_lo, *interrupt);
 	prom_printf("Please email this information to davem@redhat.com\n");
-	prom_halt();
+
+	printk("pci_intmap_match: bus %02x, devfn %02x: ",
+	       pdev->bus->number, pdev->devfn);
+	printk("IRQ [%08x.%08x.%08x.%08x] not found in interrupt-map\n",
+	       pregs->phys_hi, pregs->phys_mid, pregs->phys_lo, *interrupt);
+	printk("Please email this information to davem@redhat.com\n");
+
+	return 0;
 }
 
 static void __init pdev_fixup_irq(struct pci_dev *pdev)
@@ -703,6 +720,20 @@ static void __init pdev_fixup_irq(struct pci_dev *pdev)
 		goto have_irq;
 	}
 
+	/* Firmware gets quad-hme interrupts property totally
+	 * wrong.  It is 4 EBUS+HME devices behind a Digital bridge.
+	 * For each of the 4 instances the EBUS has interrupt property
+	 * '1' and the HME has interrupt property '2'.  So we have to
+	 * fix this up.
+	 */
+	if (!strcmp(pcp->prom_name, "SUNW,qfe") ||
+	    !strcmp(pcp->prom_name, "qfe")) {
+		if (PCI_SLOT(pdev->devfn) & ~3)
+			BUG();
+
+		prom_irq = PCI_SLOT(pdev->devfn) + 1;
+	}
+
 	/* Can we find a matching entry in the interrupt-map? */
 	if (pci_intmap_match(pdev, &prom_irq)) {
 		pdev->irq = p->irq_build(pbm, pdev, (portid << 6) | prom_irq);
@@ -738,12 +769,19 @@ static void __init pdev_fixup_irq(struct pci_dev *pdev)
 		 * ranges. -DaveM
  		 */
 		if (pdev->bus->number == pbm->pci_first_busno) {
-			slot = (pdev->devfn >> 3) - pbm->pci_first_slot;
+			slot = PCI_SLOT(pdev->devfn) - pbm->pci_first_slot;
 		} else {
+			struct pci_dev *bus_dev;
+
 			/* Underneath a bridge, use slot number of parent
-			 * bridge.
+			 * bridge which is closest to the PBM.
 			 */
-			slot = (pdev->bus->self->devfn >> 3) - pbm->pci_first_slot;
+			bus_dev = pdev->bus->self;
+			while (bus_dev->bus &&
+			       bus_dev->bus->number != pbm->pci_first_busno)
+				bus_dev = bus_dev->bus->self;
+
+			slot = PCI_SLOT(bus_dev->devfn) - pbm->pci_first_slot;
 		}
 		slot = slot << 2;