From: Marc Zyngier <marc.zyngier@arm.com>
Date: Mon, 19 Dec 2016 18:18:34 +0000
Subject: irqchip/gic-v3-its: Allow use of indirect VCPU tables
Patch-mainline: v4.14-rc1
Git-commit: 4cacac5744d57f321ae17cb15456ec97d775860e
References: FATE#323954

The VCPU tables can be quite sparse as well, and it makes sense
to use indirect tables as well if possible.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
 drivers/irqchip/irq-gic-v3-its.c |   25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1078,10 +1078,13 @@
 	return 0;
 }
 
-static bool its_parse_baser_device(struct its_node *its, struct its_baser *baser,
-				   u32 psz, u32 *order)
+static bool its_parse_indirect_baser(struct its_node *its,
+				     struct its_baser *baser,
+				     u32 psz, u32 *order)
 {
-	u64 esz = GITS_BASER_ENTRY_SIZE(its_read_baser(its, baser));
+	u64 tmp = its_read_baser(its, baser);
+	u64 type = GITS_BASER_TYPE(tmp);
+	u64 esz = GITS_BASER_ENTRY_SIZE(tmp);
 	u64 val = GITS_BASER_InnerShareable | GITS_BASER_RaWaWb;
 	u32 ids = its->device_ids;
 	u32 new_order = *order;
@@ -1120,8 +1123,9 @@
 	if (new_order >= MAX_ORDER) {
 		new_order = MAX_ORDER - 1;
 		ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
-		pr_warn("ITS@%pa: Device Table too large, reduce ids %u->%u\n",
-			&its->phys_base, its->device_ids, ids);
+		pr_warn("ITS@%pa: %s Table too large, reduce ids %u->%u\n",
+			&its->phys_base, its_base_type_string[type],
+			its->device_ids, ids);
 	}
 
 	*order = new_order;
@@ -1169,11 +1173,16 @@
 		u32 order = get_order(psz);
 		bool indirect = false;
 
-		if (type == GITS_BASER_TYPE_NONE)
+		switch (type) {
+		case GITS_BASER_TYPE_NONE:
 			continue;
 
-		if (type == GITS_BASER_TYPE_DEVICE)
-			indirect = its_parse_baser_device(its, baser, psz, &order);
+		case GITS_BASER_TYPE_DEVICE:
+		case GITS_BASER_TYPE_VCPU:
+			indirect = its_parse_indirect_baser(its, baser,
+							    psz, &order);
+			break;
+		}
 
 		err = its_setup_baser(its, baser, cache, shr, psz, order, indirect);
 		if (err < 0) {