To support per device MSI domains the ITS must provide MSI parent domain
functionality.
Provide the basic skeleton for this:
- msi_parent_ops
- child domain init callback
- the MSI parent flag set in irqdomain::flags
This does not make ITS a functional parent domain as there is no bit set in
the bus_select_mask yet, but it provides the base to implement PCI and
platform MSI support gradualy on top.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/irqchip/Kconfig | 1
drivers/irqchip/Makefile | 2 -
drivers/irqchip/irq-gic-common.h | 3 ++
drivers/irqchip/irq-gic-v3-its-msi-parent.c | 30 ++++++++++++++++++++++++++++
drivers/irqchip/irq-gic-v3-its.c | 4 +++
5 files changed, 39 insertions(+), 1 deletion(-)
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -42,6 +42,7 @@ config ARM_GIC_V3
config ARM_GIC_V3_ITS
bool
select GENERIC_MSI_IRQ
+ select ARM_GIC_MSI_LIB
default ARM_GIC_V3
config ARM_GIC_V3_ITS_PCI
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -33,7 +33,7 @@ obj-$(CONFIG_ARCH_REALVIEW) += irq-gic-
obj-$(CONFIG_ARM_GIC_MSI_LIB) += irq-gic-msi-lib.o
obj-$(CONFIG_ARM_GIC_V2M) += irq-gic-v2m.o
obj-$(CONFIG_ARM_GIC_V3) += irq-gic-v3.o irq-gic-v3-mbi.o irq-gic-common.o
-obj-$(CONFIG_ARM_GIC_V3_ITS) += irq-gic-v3-its.o irq-gic-v3-its-platform-msi.o irq-gic-v4.o
+obj-$(CONFIG_ARM_GIC_V3_ITS) += irq-gic-v3-its.o irq-gic-v3-its-platform-msi.o irq-gic-v4.o irq-gic-v3-its-msi-parent.o
obj-$(CONFIG_ARM_GIC_V3_ITS_PCI) += irq-gic-v3-its-pci-msi.o
obj-$(CONFIG_ARM_GIC_V3_ITS_FSL_MC) += irq-gic-v3-its-fsl-mc-msi.o
obj-$(CONFIG_PARTITION_PERCPU) += irq-partition-percpu.o
--- a/drivers/irqchip/irq-gic-common.h
+++ b/drivers/irqchip/irq-gic-common.h
@@ -8,6 +8,7 @@
#include <linux/of.h>
#include <linux/irqdomain.h>
+#include <linux/msi.h>
#include <linux/irqchip/arm-gic-common.h>
struct gic_quirk {
@@ -28,4 +29,6 @@ void gic_enable_quirks(u32 iidr, const s
void gic_enable_of_quirks(const struct device_node *np,
const struct gic_quirk *quirks, void *data);
+extern const struct msi_parent_ops gic_v3_its_msi_parent_ops;
+
#endif /* _IRQ_GIC_COMMON_H */
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2022 Linutronix GmbH
+// Copyright (C) 2022 Intel
+
+#include "irq-gic-common.h"
+#include "irq-gic-msi-lib.h"
+
+#define ITS_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | \
+ MSI_FLAG_USE_DEF_CHIP_OPS)
+
+#define ITS_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK | \
+ MSI_FLAG_PCI_MSIX | \
+ MSI_FLAG_MULTI_PCI_MSI)
+
+static bool its_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
+ struct irq_domain *real_parent, struct msi_domain_info *info)
+{
+ if (!gic_msi_lib_init_dev_msi_info(dev, domain, real_parent, info))
+ return false;
+
+ return true;
+}
+
+const struct msi_parent_ops gic_v3_its_msi_parent_ops = {
+ .supported_flags = ITS_MSI_FLAGS_SUPPORTED,
+ .required_flags = ITS_MSI_FLAGS_REQUIRED,
+ .bus_select_token = DOMAIN_BUS_NEXUS,
+ .prefix = "ITS-",
+ .init_dev_msi_info = its_init_dev_msi_info,
+};
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -38,6 +38,7 @@
#include <asm/exception.h>
#include "irq-gic-common.h"
+#include "irq-gic-msi-lib.h"
#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1ULL << 0)
#define ITS_FLAGS_WORKAROUND_CAVIUM_22375 (1ULL << 1)
@@ -3656,6 +3657,7 @@ static void its_irq_domain_free(struct i
}
static const struct irq_domain_ops its_domain_ops = {
+ .select = gic_msi_lib_irq_domain_select,
.alloc = its_irq_domain_alloc,
.free = its_irq_domain_free,
.activate = its_irq_domain_activate,
@@ -4918,6 +4920,8 @@ static int its_init_domain(struct fwnode
inner_domain->parent = its_parent;
irq_domain_update_bus_token(inner_domain, DOMAIN_BUS_NEXUS);
inner_domain->flags |= its->msi_domain_flags;
+ inner_domain->msi_parent_ops = &gic_v3_its_msi_parent_ops;
+ inner_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
info->ops = &its_msi_domain_ops;
info->data = its;
inner_domain->host_data = info;
