powerpc: Added PCI MSI support using the HSTA module

The PPC476GTR SoC supports message signalled interrupts (MSI) by writing
to special addresses within the High Speed Transfer Assist (HSTA) module.

This patch adds support for PCI MSI with a new system device. The DMA
window is also updated to allow access to the entire 42-bit address range
to allow PCI devices write access to the HSTA module.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/44x/Kconfig b/arch/powerpc/platforms/44x/Kconfig
index b0202d83063e..8beec7d00cac 100644
--- a/arch/powerpc/platforms/44x/Kconfig
+++ b/arch/powerpc/platforms/44x/Kconfig
@@ -206,6 +206,8 @@ config AKEBONO
         select SWIOTLB
         select 476FPE
         select PPC4xx_PCI_EXPRESS
+        select PCI_MSI
+        select PPC4xx_HSTA_MSI
         select I2C
         select I2C_IBM_IIC
         select NETDEVICES