Re: [PATCH 01/10] irqchip/gic-v3-its: Change initialization ordering for LPIs

From: Julien Thierry
Date: Mon Sep 24 2018 - 06:49:13 EST




On 21/09/18 20:59, Marc Zyngier wrote:
We currently initialize the LPIs (and the ITS) fairly early, even
before the SMP support and the CPU interface. This is a bit odd
(as LPIs are not exactly crutial for the early boot process),
and is going to cause issues when reorganizing the probing code.

Let's move this initialization later.


Reviewed-by: Julien Thierry <julien.thierry@xxxxxxx>

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
drivers/irqchip/irq-gic-v3.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index d5912f1ec884..6232f98ef81b 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -653,7 +653,9 @@ early_param("irqchip.gicv3_nolpi", gicv3_nolpi_cfg);
static int gic_dist_supports_lpis(void)
{
- return !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS) && !gicv3_nolpi;
+ return (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) &&
+ !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS) &&
+ !gicv3_nolpi);
}
static void gic_cpu_init(void)
@@ -673,10 +675,6 @@ static void gic_cpu_init(void)
gic_cpu_config(rbase, gic_redist_wait_for_rwp);
- /* Give LPIs a spin */
- if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
- its_cpu_init();
-
/* initialise system registers */
gic_cpu_sys_reg_init();
}
@@ -689,6 +687,10 @@ static void gic_cpu_init(void)
static int gic_starting_cpu(unsigned int cpu)
{
gic_cpu_init();
+
+ if (gic_dist_supports_lpis())
+ its_cpu_init();
+
return 0;
}
@@ -1127,14 +1129,16 @@ static int __init gic_init_bases(void __iomem *dist_base,
gic_update_vlpi_properties();
- if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
- its_init(handle, &gic_data.rdists, gic_data.domain);
-
gic_smp_init();
gic_dist_init();
gic_cpu_init();
gic_cpu_pm_init();
+ if (gic_dist_supports_lpis()) {
+ its_init(handle, &gic_data.rdists, gic_data.domain);
+ its_cpu_init();
+ }
+
return 0;
out_free:


--
Julien Thierry