On Mon, Sep 23, 2019 at 07:25:33PM +0100, Marc Zyngier wrote:
> 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 <m...@kernel.org>
Reviewed-by: Andrew Murray <andrew.mur...@arm.com>
> ---
> 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
>
