[PATCH v5 2/5] irqchip/gic-v3: Enable support for SGIs to act as NMIs

From: Sumit Garg
Date: Wed Oct 14 2020 - 07:13:00 EST


Add support to handle SGIs as regular NMIs. As SGIs or IPIs defaults to a
special flow handler: handle_percpu_devid_fasteoi_ipi(), so skip NMI
handler update in case of SGIs.

Also, enable NMI support prior to gic_smp_init() as allocation of SGIs
as IRQs/NMIs happen as part of this routine.

Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx>
---
drivers/irqchip/irq-gic-v3.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 16fecc0..5efc865 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -477,6 +477,11 @@ static int gic_irq_nmi_setup(struct irq_data *d)
if (WARN_ON(gic_irq(d) >= 8192))
return -EINVAL;

+ if (get_intid_range(d) == SGI_RANGE) {
+ gic_irq_set_prio(d, GICD_INT_NMI_PRI);
+ return 0;
+ }
+
/* desc lock should already be held */
if (gic_irq_in_rdist(d)) {
u32 idx = gic_get_ppi_index(d);
@@ -514,6 +519,11 @@ static void gic_irq_nmi_teardown(struct irq_data *d)
if (WARN_ON(gic_irq(d) >= 8192))
return;

+ if (get_intid_range(d) == SGI_RANGE) {
+ gic_irq_set_prio(d, GICD_INT_DEF_PRI);
+ return;
+ }
+
/* desc lock should already be held */
if (gic_irq_in_rdist(d)) {
u32 idx = gic_get_ppi_index(d);
@@ -1708,6 +1718,7 @@ static int __init gic_init_bases(void __iomem *dist_base,

gic_dist_init();
gic_cpu_init();
+ gic_enable_nmi_support();
gic_smp_init();
gic_cpu_pm_init();

@@ -1719,8 +1730,6 @@ static int __init gic_init_bases(void __iomem *dist_base,
gicv2m_init(handle, gic_data.domain);
}

- gic_enable_nmi_support();
-
return 0;

out_free:
--
2.7.4