irqchip/gic-v3-its: Factor out wait_for_syncr primitive

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>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191027144234.8395-3-maz@kernel.org
Link: https://lore.kernel.org/r/20191108165805.3071-3-maz@kernel.org

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index d5d8f8fc097396399bd2f1c85792eb067f41b9b1..78d3e73fc9c74e0e5825a265a614296f34b6c2d2 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1093,6 +1093,12 @@ 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);
@@ -2775,8 +2781,7 @@ 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;
        }
@@ -2932,8 +2937,7 @@ 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);
        }
@@ -2975,8 +2979,7 @@ 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)