PCI: Add 'nodomains' boot option, and pci_domains_supported global
* Introduce pci_domains_supported global, hardcoded to zero if
!CONFIG_PCI_DOMAINS.
* Introduce 'nodomains' boot option, which clears pci_domains_supported
on platforms that enable it by default (x86, x86-64, and others when
they are converted to use this).
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e9acd55..d006e8b6 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1274,6 +1274,8 @@
noaer [PCIE] If the PCIEAER kernel config parameter is
enabled, this kernel boot option can be used to
disable the use of PCIE advanced error reporting.
+ nodomains [PCI] Disable support for multiple PCI
+ root domains (aka PCI segments, in ACPI-speak).
nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI
Configuration
nomsi [MSI] If the PCI_MSI kernel config parameter is
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 2dd5c28..728b3c8 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -23,6 +23,10 @@
unsigned int pci_pm_d3_delay = 10;
+#ifdef CONFIG_PCI_DOMAINS
+int pci_domains_supported = 1;
+#endif
+
#define DEFAULT_CARDBUS_IO_SIZE (256)
#define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
/* pci=cbmemsize=nnM,cbiosize=nn can override this */
@@ -1567,6 +1571,13 @@
return bars;
}
+static void __devinit pci_no_domains(void)
+{
+#ifdef CONFIG_PCI_DOMAINS
+ pci_domains_supported = 0;
+#endif
+}
+
static int __devinit pci_init(void)
{
struct pci_dev *dev = NULL;
@@ -1588,6 +1599,8 @@
pci_no_msi();
} else if (!strcmp(str, "noaer")) {
pci_no_aer();
+ } else if (!strcmp(str, "nodomains")) {
+ pci_no_domains();
} else if (!strncmp(str, "cbiosize=", 9)) {
pci_cardbus_io_size = memparse(str + 9, &str);
} else if (!strncmp(str, "cbmemsize=", 10)) {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 038a0dc..768b933 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -685,13 +685,16 @@
* a PCI domain is defined to be a set of PCI busses which share
* configuration space.
*/
-#ifndef CONFIG_PCI_DOMAINS
+#ifdef CONFIG_PCI_DOMAINS
+extern int pci_domains_supported;
+#else
+enum { pci_domains_supported = 0 };
static inline int pci_domain_nr(struct pci_bus *bus) { return 0; }
static inline int pci_proc_domain(struct pci_bus *bus)
{
return 0;
}
-#endif
+#endif /* CONFIG_PCI_DOMAINS */
#else /* CONFIG_PCI is not enabled */