After refactoring DT code, we let ACPI to build ITS PCI MSI domain
and do requester ID to device ID translation using IORT table.

We have now full PCI MSI domain stack, thus we can enable ITS initialization
from GICv3 core driver for ACPI scenario.

Signed-off-by: Tomasz Nowicki <redacted>
---
 drivers/irqchip/irq-gic-v3-its-pci-msi.c | 48 ++++++++++++++++++++++++++++++--
 drivers/irqchip/irq-gic-v3.c             |  3 +-
 2 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
index cfd35da..09ae2d8 100644
--- a/drivers/irqchip/irq-gic-v3-its-pci-msi.c
+++ b/drivers/irqchip/irq-gic-v3-its-pci-msi.c

@@ -15,6 +15,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/acpi.h>
+#include <linux/iort.h>
 #include <linux/msi.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>

@@ -59,8 +61,10 @@ static int its_pci_msi_vec_count(struct pci_dev *pdev)
 static int its_get_pci_alias(struct pci_dev *pdev, u16 alias, void *data)
 {
 	struct its_pci_alias *dev_alias = data;
+	u32 dev_id;
 
-	dev_alias->dev_id = alias;
+	dev_alias->dev_id = iort_find_pci_id(pdev, alias, &dev_id) == 0 ?
+								dev_id : alias;