[PATCH v3 03/59] irqchip/gic-v3: Add VLPI/DirectLPI discovery

Marc Zyngier
2017-07-31T17:25:37Z

Add helper functions that probe for VLPI and DirectLPI properties.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
drivers/irqchip/irq-gic-v3.c | 24 +++++++++++++++++++++++-
include/linux/irqchip/arm-gic-v3.h | 3 +++
2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 640f621c7f75..17f0ad41864f 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
+ * Copyright (C) 2013-2017 ARM Limited, All Rights Reserved.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
@@ -504,6 +504,24 @@ static int gic_populate_rdist(void)
return -ENODEV;
}

+static int __gic_update_vlpi_properties(struct redist_region *region,
+ void __iomem *ptr)
+{
+ u64 typer = gic_read_typer(ptr + GICR_TYPER);
+ gic_data.rdists.has_vlpis &= !!(typer & GICR_TYPER_VLPIS);
+ gic_data.rdists.has_direct_lpi &= !!(typer & GICR_TYPER_DirectLPIS);
+
+ return 1;
+}
+
+static void gic_update_vlpi_properties(void)
+{
+ gic_iterate_rdists(__gic_update_vlpi_properties);
+ pr_info("%sVLPI support, %sdirect LPI support\n",
+ !gic_data.rdists.has_vlpis ? "no " : "",
+ !gic_data.rdists.has_direct_lpi ? "no " : "");
+}
+
static void gic_cpu_sys_reg_init(void)
{
/*
@@ -968,6 +986,8 @@ static int __init gic_init_bases(void __iomem *dist_base,
gic_data.domain = irq_domain_create_tree(handle, &gic_irq_domain_ops,
&gic_data);
gic_data.rdists.rdist = alloc_percpu(typeof(*gic_data.rdists.rdist));
+ gic_data.rdists.has_vlpis = true;
+ gic_data.rdists.has_direct_lpi = true;

if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdists.rdist)) {
err = -ENOMEM;
@@ -976,6 +996,8 @@ static int __init gic_init_bases(void __iomem *dist_base,

set_handle_irq(gic_handle_irq);

+ 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);

diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 6a1f87ff94e2..20a553423ac7 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -204,6 +204,7 @@

#define GICR_TYPER_PLPIS (1U << 0)
#define GICR_TYPER_VLPIS (1U << 1)
+#define GICR_TYPER_DirectLPIS (1U << 3)
#define GICR_TYPER_LAST (1U << 4)

#define GIC_V3_REDIST_SIZE 0x20000
@@ -487,6 +488,8 @@ struct rdists {
struct page *prop_page;
int id_bits;
u64 flags;
+ bool has_vlpis;
+ bool has_direct_lpi;
};

struct irq_domain;
--
2.11.0