[PATCH v2 02/11] irqchip/gic-v3-its: Factor out wait_for_syncr primitive

From: Marc Zyngier
Date: Fri Nov 08 2019 - 11:58:45 EST


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@xxxxxxxxxx>
Reviewed-by: Zenghui Yu <yuzenghui@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20191027144234.8395-3-maz@xxxxxxxxxx
---
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 cc6aea602a7a..34eab323ea69 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1090,6 +1090,12 @@ 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);
@@ -2772,8 +2778,7 @@ 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;
}
@@ -2929,8 +2934,7 @@ 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);
}
@@ -2972,8 +2976,7 @@ 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