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From:   Marc Zyngier <maz@kernel.org>
To:     kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org
Cc:     Eric Auger <eric.auger@redhat.com>,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Jason Cooper <jason@lakedaemon.net>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Andrew Murray <Andrew.Murray@arm.com>
Subject: [PATCH 02/35] irqchip/gic-v3-its: Factor out wait_for_syncr primitive
Date:   Mon, 23 Sep 2019 19:25:33 +0100
Message-Id: <20190923182606.32100-3-maz@kernel.org>
In-Reply-To: <20190923182606.32100-1-maz@kernel.org>
References: <20190923182606.32100-1-maz@kernel.org>
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Waiting for a redistributor to have performed an operation is a
common thing to do, and the idiom is already spread around.
As we're going to make even more use of this, let's have a primitive
that does just that.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/irqchip/irq-gic-v3-its.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 62e54f1a248b..58cb233cf138 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1075,6 +1075,12 @@ static void lpi_write_config(struct irq_data *d, u8 clr, u8 set)
 		dsb(ishst);
 }
 
+static void wait_for_syncr(void __iomem *rdbase)
+{
+	while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
+		cpu_relax();
+}
+
 static void lpi_update_config(struct irq_data *d, u8 clr, u8 set)
 {
 	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
@@ -2757,8 +2763,7 @@ static void its_vpe_db_proxy_move(struct its_vpe *vpe, int from, int to)
 
 		rdbase = per_cpu_ptr(gic_rdists->rdist, from)->rd_base;
 		gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_CLRLPIR);
-		while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
-			cpu_relax();
+		wait_for_syncr(rdbase);
 
 		return;
 	}
@@ -2914,8 +2919,7 @@ static void its_vpe_send_inv(struct irq_data *d)
 
 		rdbase = per_cpu_ptr(gic_rdists->rdist, vpe->col_idx)->rd_base;
 		gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_INVLPIR);
-		while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
-			cpu_relax();
+		wait_for_syncr(rdbase);
 	} else {
 		its_vpe_send_cmd(vpe, its_send_inv);
 	}
@@ -2957,8 +2961,7 @@ static int its_vpe_set_irqchip_state(struct irq_data *d,
 			gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_SETLPIR);
 		} else {
 			gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_CLRLPIR);
-			while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
-				cpu_relax();
+			wait_for_syncr(rdbase);
 		}
 	} else {
 		if (state)
-- 
2.20.1