tile PCI RC: support I/O space access

To enable this functionality, configure CONFIG_TILE_PCI_IO.  Without
this flag, the kernel still assigns I/O address ranges to the
devices, but no TRIO resource and mapping support is provided.

We assign disjoint I/O address ranges to separate PCIe domains.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index 24565a7ffe6d..bfff76947f83 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -396,6 +396,16 @@ config NO_IOMEM
 config NO_IOPORT
         def_bool !PCI
 
+config TILE_PCI_IO
+        bool "PCI I/O space support"
+        default n
+        depends on PCI
+        depends on TILEGX
+        ---help---
+          Enable PCI I/O space support on TILEGx. Since the PCI I/O space
+          is used by few modern PCIe endpoint devices, its support is disabled
+          by default to save the TRIO PIO Region resource for other purposes.
+
 source "drivers/pci/Kconfig"
 
 config TILE_USB