aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorDavid S. Miller <davem@sunset.davemloft.net>2006-06-10 04:06:25 -0400
committerDavid S. Miller <davem@sunset.davemloft.net>2006-06-10 04:06:25 -0400
commit46b304934de417a2238d659ef6459a74cb3f5e6b (patch)
tree770b99e2723170f237d9159541484bba7dec21e8
parentc29ca9d1812f2abacaefa7daa31e085600128938 (diff)
[SPARC64]: Avoid JBUS errors on some Niagara systems.
Doing PCI config space accesses to non-present PCI slots can result in fatal JBUS errors if the PCI config access hypervisor call is performed on cpus other than the boot cpu. PCI config space accesses to present PCI slots works just fine. Recursively traverse the OBP device tree under the PCI controller node and record all present device IDs into a small hash table. Avoid the hypervisor call for any PCI config space access attempt for a device not recorded in the hash table. Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--arch/sparc64/kernel/pci_sun4v.c124
1 files changed, 118 insertions, 6 deletions
diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index 2b7a1f316a93..0c0895202970 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -599,18 +599,128 @@ struct pci_iommu_ops pci_sun4v_iommu_ops = {
599 599
600/* SUN4V PCI configuration space accessors. */ 600/* SUN4V PCI configuration space accessors. */
601 601
602static inline int pci_sun4v_out_of_range(struct pci_pbm_info *pbm, unsigned int bus, unsigned int device, unsigned int func) 602struct pdev_entry {
603 struct pdev_entry *next;
604 u32 devhandle;
605 unsigned int bus;
606 unsigned int device;
607 unsigned int func;
608};
609
610#define PDEV_HTAB_SIZE 16
611#define PDEV_HTAB_MASK (PDEV_HTAB_SIZE - 1)
612static struct pdev_entry *pdev_htab[PDEV_HTAB_SIZE];
613
614static inline unsigned int pdev_hashfn(u32 devhandle, unsigned int bus, unsigned int device, unsigned int func)
603{ 615{
604 if (bus == pbm->pci_first_busno) { 616 unsigned int val;
605 if (device == 0 && func == 0) 617
606 return 0; 618 val = (devhandle ^ (devhandle >> 4));
607 return 1; 619 val ^= bus;
620 val ^= device;
621 val ^= func;
622
623 return val & PDEV_HTAB_MASK;
624}
625
626static int pdev_htab_add(u32 devhandle, unsigned int bus, unsigned int device, unsigned int func)
627{
628 struct pdev_entry *p = kmalloc(sizeof(*p), GFP_KERNEL);
629 struct pdev_entry **slot;
630
631 if (!p)
632 return -ENOMEM;
633
634 slot = &pdev_htab[pdev_hashfn(devhandle, bus, device, func)];
635 p->next = *slot;
636 *slot = p;
637
638 p->devhandle = devhandle;
639 p->bus = bus;
640 p->device = device;
641 p->func = func;
642
643 return 0;
644}
645
646/* Recursively descend into the OBP device tree, rooted at toplevel_node,
647 * looking for a PCI device matching bus and devfn.
648 */
649static int obp_find(struct linux_prom_pci_registers *pregs, int toplevel_node, unsigned int bus, unsigned int devfn)
650{
651 toplevel_node = prom_getchild(toplevel_node);
652
653 while (toplevel_node != 0) {
654 int ret = obp_find(pregs, toplevel_node, bus, devfn);
655
656 if (ret != 0)
657 return ret;
658
659 ret = prom_getproperty(toplevel_node, "reg", (char *) pregs,
660 sizeof(*pregs) * PROMREG_MAX);
661 if (ret == 0 || ret == -1)
662 goto next_sibling;
663
664 if (((pregs[0].phys_hi >> 16) & 0xff) == bus &&
665 ((pregs[0].phys_hi >> 8) & 0xff) == devfn)
666 break;
667
668 next_sibling:
669 toplevel_node = prom_getsibling(toplevel_node);
670 }
671
672 return toplevel_node;
673}
674
675static int pdev_htab_populate(struct pci_pbm_info *pbm)
676{
677 struct linux_prom_pci_registers pr[PROMREG_MAX];
678 u32 devhandle = pbm->devhandle;
679 unsigned int bus;
680
681 for (bus = pbm->pci_first_busno; bus <= pbm->pci_last_busno; bus++) {
682 unsigned int devfn;
683
684 for (devfn = 0; devfn < 256; devfn++) {
685 unsigned int device = PCI_SLOT(devfn);
686 unsigned int func = PCI_FUNC(devfn);
687
688 if (obp_find(pr, pbm->prom_node, bus, devfn)) {
689 int err = pdev_htab_add(devhandle, bus,
690 device, func);
691 if (err)
692 return err;
693 }
694 }
695 }
696
697 return 0;
698}
699
700static struct pdev_entry *pdev_find(u32 devhandle, unsigned int bus, unsigned int device, unsigned int func)
701{
702 struct pdev_entry *p;
703
704 p = pdev_htab[pdev_hashfn(devhandle, bus, device, func)];
705 while (p) {
706 if (p->devhandle == devhandle &&
707 p->bus == bus &&
708 p->device == device &&
709 p->func == func)
710 break;
711
712 p = p->next;
608 } 713 }
609 714
715 return p;
716}
717
718static inline int pci_sun4v_out_of_range(struct pci_pbm_info *pbm, unsigned int bus, unsigned int device, unsigned int func)
719{
610 if (bus < pbm->pci_first_busno || 720 if (bus < pbm->pci_first_busno ||
611 bus > pbm->pci_last_busno) 721 bus > pbm->pci_last_busno)
612 return 1; 722 return 1;
613 return 0; 723 return pdev_find(pbm->devhandle, bus, device, func) == NULL;
614} 724}
615 725
616static int pci_sun4v_read_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn, 726static int pci_sun4v_read_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
@@ -1063,6 +1173,8 @@ static void pci_sun4v_pbm_init(struct pci_controller_info *p, int prom_node, u32
1063 1173
1064 pci_sun4v_get_bus_range(pbm); 1174 pci_sun4v_get_bus_range(pbm);
1065 pci_sun4v_iommu_init(pbm); 1175 pci_sun4v_iommu_init(pbm);
1176
1177 pdev_htab_populate(pbm);
1066} 1178}
1067 1179
1068void sun4v_pci_init(int node, char *model_name) 1180void sun4v_pci_init(int node, char *model_name)