[tip: irq/core] irqchip/gic-v3-its: Provide MSI parent infrastructure

From: tip-bot2 for Thomas Gleixner
Date: Wed Jul 10 2024 - 12:30:50 EST

The following commit has been merged into the irq/core branch of tip:

Commit-ID: e3baf5e45373c788bc7e0d899d1563f2acdb0fa8
Gitweb: https://git.kernel.org/tip/e3baf5e45373c788bc7e0d899d1563f2acdb0fa8
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Sun, 23 Jun 2024 17:18:36 +02:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Wed, 10 Jul 2024 18:19:23 +02:00

irqchip/gic-v3-its: Provide MSI parent infrastructure

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 gradually on top.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
Signed-off-by: Shivamurthy Shastri <shivamurthy.shastri@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240623142234.903076277@xxxxxxxxxxxxx



---
drivers/irqchip/Kconfig | 1 +-
drivers/irqchip/Makefile | 2 +-
drivers/irqchip/irq-gic-common.h | 3 ++-
drivers/irqchip/irq-gic-v3-its-msi-parent.c | 31 ++++++++++++++++++++-
drivers/irqchip/irq-gic-v3-its.c | 5 +++-
5 files changed, 41 insertions(+), 1 deletion(-)
create mode 100644 drivers/irqchip/irq-gic-v3-its-msi-parent.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 3e3cbe9..ee78716 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -41,6 +41,7 @@ config ARM_GIC_V3
config ARM_GIC_V3_ITS
bool
select GENERIC_MSI_IRQ
+ select IRQ_MSI_LIB
default ARM_GIC_V3

config ARM_GIC_V3_ITS_PCI
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index f5e0fa9..def6fea 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -32,7 +32,7 @@ obj-$(CONFIG_ARCH_REALVIEW) += irq-gic-realview.o
obj-$(CONFIG_IRQ_MSI_LIB) += irq-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
diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
index f407cce..eb4a220 100644
--- 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 {
@@ -29,6 +30,8 @@ void gic_enable_quirks(u32 iidr, const struct gic_quirk *quirks,
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;
+
#define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING (1 << 0)
#define RDIST_FLAGS_RD_TABLES_PREALLOCATED (1 << 1)
#define RDIST_FLAGS_FORCE_NON_SHAREABLE (1 << 2)
diff --git a/drivers/irqchip/irq-gic-v3-its-msi-parent.c b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
new file mode 100644
index 0000000..cdc0844
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2022 Linutronix GmbH
+// Copyright (C) 2022 Intel
+
+#include "irq-gic-common.h"
+#include "irq-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 | \
+ MSI_FLAG_PCI_MSI_MASK_PARENT)
+
+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 (!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,
+};
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index af5297e..047e566 100644
--- 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-msi-lib.h"

#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING (1ULL << 0)
#define ITS_FLAGS_WORKAROUND_CAVIUM_22375 (1ULL << 1)
@@ -3708,6 +3709,7 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
}

static const struct irq_domain_ops its_domain_ops = {
+ .select = msi_lib_irq_domain_select,
.alloc = its_irq_domain_alloc,
.free = its_irq_domain_free,
.activate = its_irq_domain_activate,
@@ -5013,6 +5015,9 @@ static int its_init_domain(struct its_node *its)

irq_domain_update_bus_token(inner_domain, DOMAIN_BUS_NEXUS);

+ inner_domain->msi_parent_ops = &gic_v3_its_msi_parent_ops;
+ inner_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
+
return 0;
}