Commit 48f71d56 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

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: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarAnna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: default avatarShivamurthy Shastri <shivamurthy.shastri@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240623142234.903076277@linutronix.de
parent 72e257c6

drivers/irqchip/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -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

drivers/irqchip/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -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

drivers/irqchip/irq-gic-common.h

+3 −0
Original line number Diff line number Diff line
@@ -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)

drivers/irqchip/irq-gic-v3-its-msi-parent.c

0 → 100644
+31 −0
Original line number Diff line number Diff line 
// 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,

};

drivers/irqchip/irq-gic-v3-its.c

+5 −0
Original line number Diff line number Diff line
@@ -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)
@@ -3688,6 +3689,7 @@ 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,
@@ -4993,6 +4995,9 @@ 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;

}