Re: [PATCH] irqchip: mips-gic: Handle case with cluster without CPU cores
From: Jiaxun Yang
Date: Fri Oct 25 2024 - 12:43:47 EST
在2024年10月25日十月 下午4:46,Gregory CLEMENT写道:
> It is possible to have no CPU cores in a cluster; in such cases, it is
> not possible to access the GIC, and any indirect access leads to an
> exception. This patch dynamically skips the indirect access in such
> situations.
Hi Gregory,
I'm a little bit confused here, as I have never seen such wired configuration.
Is second cluster IOCU only?
Thanks
- Jiaxun
>
> Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
> ---
> This patch is a follow-up of the series "MIPS: Support I6500
> multi-cluster configuration"
> https://lore.kernel.org/lkml/20241019071037.145314-1-arikalo@xxxxxxxxx/#t
> ---
> drivers/irqchip/irq-mips-gic.c | 20 ++++++++++++++++----
> 1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
> index f42f69bbd6fb1..bca8053864b2c 100644
> --- a/drivers/irqchip/irq-mips-gic.c
> +++ b/drivers/irqchip/irq-mips-gic.c
> @@ -141,7 +141,8 @@ static bool gic_irq_lock_cluster(struct irq_data *d)
> cl = cpu_cluster(&cpu_data[cpu]);
> if (cl == cpu_cluster(¤t_cpu_data))
> return false;
> -
> + if (mips_cps_numcores(cl) == 0)
> + return false;
> mips_cm_lock_other(cl, 0, 0, CM_GCR_Cx_OTHER_BLOCK_GLOBAL);
> return true;
> }
> @@ -507,6 +508,9 @@ static void gic_mask_local_irq_all_vpes(struct irq_data *d)
> struct gic_all_vpes_chip_data *cd;
> int intr, cpu;
>
> + if (!mips_cps_multicluster_cpus())
> + return;
> +
> intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
> cd = irq_data_get_irq_chip_data(d);
> cd->mask = false;
> @@ -520,6 +524,9 @@ static void gic_unmask_local_irq_all_vpes(struct
> irq_data *d)
> struct gic_all_vpes_chip_data *cd;
> int intr, cpu;
>
> + if (!mips_cps_multicluster_cpus())
> + return;
> +
> intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
> cd = irq_data_get_irq_chip_data(d);
> cd->mask = true;
> @@ -687,8 +694,10 @@ static int gic_irq_domain_map(struct irq_domain
> *d, unsigned int virq,
> if (!gic_local_irq_is_routable(intr))
> return -EPERM;
>
> - for_each_online_cpu_gic(cpu, &gic_lock)
> - write_gic_vo_map(mips_gic_vx_map_reg(intr), map);
> + if (mips_cps_multicluster_cpus()) {
> + for_each_online_cpu_gic(cpu, &gic_lock)
> + write_gic_vo_map(mips_gic_vx_map_reg(intr), map);
> + }
>
> return 0;
> }
> @@ -982,7 +991,7 @@ static int __init gic_of_init(struct device_node *node,
> change_gic_trig(i, GIC_TRIG_LEVEL);
> write_gic_rmask(i);
> }
> - } else {
> + } else if (mips_cps_numcores(cl) != 0) {
> mips_cm_lock_other(cl, 0, 0, CM_GCR_Cx_OTHER_BLOCK_GLOBAL);
> for (i = 0; i < gic_shared_intrs; i++) {
> change_gic_redir_pol(i, GIC_POL_ACTIVE_HIGH);
> @@ -990,6 +999,9 @@ static int __init gic_of_init(struct device_node *node,
> write_gic_redir_rmask(i);
> }
> mips_cm_unlock_other();
> +
> + } else {
> + pr_warn("No CPU cores on the cluster %d skip it\n", cl);
> }
> }
>
>
> ---
> base-commit: 10e44701486e25d630d714ace2b0c6d9a178b331
> change-id: 20241025-no-cpu-cluster-support-1745e8abd7d1
>
> Best regards,
> --
> Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
--
- Jiaxun