From: Marc Zyngier <maz@kernel.org>
Date: Tue, 24 Dec 2019 11:10:37 +0000
Subject: irqchip/gic-v4.1: Suppress per-VLPI doorbell
Git-commit: 3858d4dfdfb845e51ee8b4045f61ccba2c3111ee
Patch-mainline: v5.6-rc1
References: jsc#SLE-14773 jsc#SLE-14763

Since GICv4.1 gives us a per-VPE doorbell, avoid programming anything
else on VMOVI/VMAPI/VMAPTI and on any other action that would have
otherwise resulted in a per-VLPI doorbell to be programmed.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-15-maz@kernel.org
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
---
 drivers/irqchip/irq-gic-v3-its.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 1d8d96a8cc26..53e91c98acb2 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -718,7 +718,7 @@ static struct its_vpe *its_build_vmapti_cmd(struct its_node *its,
 {
 	u32 db;
 
-	if (desc->its_vmapti_cmd.db_enabled)
+	if (!is_v4_1(its) && desc->its_vmapti_cmd.db_enabled)
 		db = desc->its_vmapti_cmd.vpe->vpe_db_lpi;
 	else
 		db = 1023;
@@ -741,7 +741,7 @@ static struct its_vpe *its_build_vmovi_cmd(struct its_node *its,
 {
 	u32 db;
 
-	if (desc->its_vmovi_cmd.db_enabled)
+	if (!is_v4_1(its) && desc->its_vmovi_cmd.db_enabled)
 		db = desc->its_vmovi_cmd.vpe->vpe_db_lpi;
 	else
 		db = 1023;
@@ -1353,6 +1353,13 @@ static void its_vlpi_set_doorbell(struct irq_data *d, bool enable)
 	u32 event = its_get_event_id(d);
 	struct its_vlpi_map *map;
 
+	/*
+	 * GICv4.1 does away with the per-LPI nonsense, nothing to do
+	 * here.
+	 */
+	if (is_v4_1(its_dev->its))
+		return;
+
 	map = dev_event_to_vlpi_map(its_dev, event);
 
 	if (map->db_enabled == enable)
-- 
2.28.0