msi: introduce ARCH_SUPPORTS_MSI Kconfig option (rev2)

Allows architectures to advertise that they support MSI rather than listing
each architecture as a PCI_MSI dependency.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

arch/arm/Kconfig

@@ -255,6 +255,7 @@ config ARCH_IOP13XX
 	depends on MMU
 	select PLAT_IOP
 	select PCI
+	select ARCH_SUPPORTS_MSI
 	help
 	  Support for Intel's IOP13XX (XScale) family of processors.
 

arch/i386/Kconfig

@@ -1073,6 +1073,7 @@ config PCI
 	bool "PCI support" if !X86_VISWS
 	depends on !X86_VOYAGER
 	default y if X86_VISWS
+	select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
 	help
 	  Find out whether you have a PCI motherboard. PCI is the name of a
 	  bus system, i.e. the way the CPU talks to the other stuff inside

arch/ia64/Kconfig

@@ -14,6 +14,7 @@ config IA64
 	select PCI if (!IA64_HP_SIM)
 	select ACPI if (!IA64_HP_SIM)
 	select PM if (!IA64_HP_SIM)
+	select ARCH_SUPPORTS_MSI
 	default y
 	help
 	  The Itanium Processor Family is Intel's 64-bit successor to

arch/sparc64/Kconfig

@@ -306,6 +306,7 @@ config SUN_IO
 
 config PCI
 	bool "PCI support"
+	select ARCH_SUPPORTS_MSI
 	help
 	  Find out whether you have a PCI motherboard. PCI is the name of a
 	  bus system, i.e. the way the CPU talks to the other stuff inside

arch/x86_64/Kconfig

@@ -676,6 +676,7 @@ menu "Bus options (PCI etc.)"
 
 config PCI
 	bool "PCI support"
+	select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
 
 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
 config PCI_DIRECT

drivers/pci/Kconfig

 #
 # PCI configuration
 #
+config ARCH_SUPPORTS_MSI
+	bool
+	default n
+
 config PCI_MSI
 	bool "Message Signaled Interrupts (MSI and MSI-X)"
 	depends on PCI
-	depends on (X86_LOCAL_APIC && X86_IO_APIC) || IA64 || SPARC64
+	depends on ARCH_SUPPORTS_MSI
 	help
 	   This allows device drivers to enable MSI (Message Signaled
 	   Interrupts).  Message Signaled Interrupts enable a device to