The following commit has been merged into the irq/core branch of tip: Commit-ID: 64e4f92275a52e1c1b89a556a45807fdbfd4b28c Gitweb: https://git.kernel.org/tip/64e4f92275a52e1c1b89a556a45807fdbfd4b28c Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Sun, 23 Jun 2024 17:18:34 +02:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Wed, 10 Jul 2024 18:19:23 +02:00 irqchip: Provide irq-msi-lib All irqdomains which provide MSI parent domain functionality for per device MSI domains need to provide a select() callback for the irqdomain and a function to initialize the child domain. Most of these functions would just be copy&paste with minimal modifications, so provide a library function which implements the required functionality and is customizable via parent_domain::msi_parent_ops. The check for the supported bus tokens in msi_lib_init_dev_msi_info() is expanded step by step within the next patches. 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/20240623142234.840975799@xxxxxxxxxxxxx --- drivers/irqchip/Kconfig | 3 +- drivers/irqchip/Makefile | 1 +- drivers/irqchip/irq-msi-lib.c | 112 +++++++++++++++++++++++++++++++++- drivers/irqchip/irq-msi-lib.h | 19 ++++++- 4 files changed, 135 insertions(+) create mode 100644 drivers/irqchip/irq-msi-lib.c create mode 100644 drivers/irqchip/irq-msi-lib.h diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 344c484..3e3cbe9 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -74,6 +74,9 @@ config ARM_VIC_NR The maximum number of VICs available in the system, for power management. +config IRQ_MSI_LIB + bool + config ARMADA_370_XP_IRQ bool select GENERIC_IRQ_CHIP diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index 2df72b7..f5e0fa9 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_ARCH_SPEAR3XX) += spear-shirq.o obj-$(CONFIG_ARM_GIC) += irq-gic.o irq-gic-common.o obj-$(CONFIG_ARM_GIC_PM) += irq-gic-pm.o obj-$(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 diff --git a/drivers/irqchip/irq-msi-lib.c b/drivers/irqchip/irq-msi-lib.c new file mode 100644 index 0000000..ec1a10f --- /dev/null +++ b/drivers/irqchip/irq-msi-lib.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2022 Linutronix GmbH +// Copyright (C) 2022 Intel + +#include <linux/export.h> + +#include "irq-msi-lib.h" + +/** + * msi_lib_init_dev_msi_info - Domain info setup for MSI domains + * @dev: The device for which the domain is created for + * @domain: The domain providing this callback + * @real_parent: The real parent domain of the domain to be initialized + * which might be a domain built on top of @domain or + * @domain itself + * @info: The domain info for the domain to be initialize + * + * This function is to be used for all types of MSI domains above the root + * parent domain and any intermediates. The topmost parent domain specific + * functionality is determined via @real_parent. + * + * All intermediate domains between the root and the device domain must + * have either msi_parent_ops.init_dev_msi_info = msi_parent_init_dev_msi_info + * or invoke it down the line. + */ +bool msi_lib_init_dev_msi_info(struct device *dev, struct irq_domain *domain, + struct irq_domain *real_parent, + struct msi_domain_info *info) +{ + const struct msi_parent_ops *pops = real_parent->msi_parent_ops; + + /* Parent ops available? */ + if (WARN_ON_ONCE(!pops)) + return false; + + /* + * MSI parent domain specific settings. For now there is only the + * root parent domain, e.g. NEXUS, acting as a MSI parent, but it is + * possible to stack MSI parents. See x86 vector -> irq remapping + */ + if (domain->bus_token == pops->bus_select_token) { + if (WARN_ON_ONCE(domain != real_parent)) + return false; + } else { + WARN_ON_ONCE(1); + return false; + } + + /* Is the target domain bus token supported? */ + switch(info->bus_token) { + default: + /* + * This should never be reached. See + * msi_lib_irq_domain_select() + */ + WARN_ON_ONCE(1); + return false; + } + + /* + * Mask out the domain specific MSI feature flags which are not + * supported by the real parent. + */ + info->flags &= pops->supported_flags; + /* Enforce the required flags */ + info->flags |= pops->required_flags; + + /* Chip updates for all child bus types */ + if (!info->chip->irq_eoi) + info->chip->irq_eoi = irq_chip_eoi_parent; + + /* + * The device MSI domain can never have a set affinity callback. It + * always has to rely on the parent domain to handle affinity + * settings. The device MSI domain just has to write the resulting + * MSI message into the hardware which is the whole purpose of the + * device MSI domain aside of mask/unmask which is provided e.g. by + * PCI/MSI device domains. + */ + info->chip->irq_set_affinity = msi_domain_set_affinity; + return true; +} +EXPORT_SYMBOL_GPL(msi_lib_init_dev_msi_info); + +/** + * msi_lib_irq_domain_select - Shared select function for NEXUS domains + * @d: Pointer to the irq domain on which select is invoked + * @fwspec: Firmware spec describing what is searched + * @bus_token: The bus token for which a matching irq domain is looked up + * + * Returns: %0 if @d is not what is being looked for + * + * %1 if @d is either the domain which is directly searched for or + * if @d is providing the parent MSI domain for the functionality + * requested with @bus_token. + */ +int msi_lib_irq_domain_select(struct irq_domain *d, struct irq_fwspec *fwspec, + enum irq_domain_bus_token bus_token) +{ + const struct msi_parent_ops *ops = d->msi_parent_ops; + u32 busmask = BIT(bus_token); + + if (fwspec->fwnode != d->fwnode || fwspec->param_count != 0) + return 0; + + /* Handle pure domain searches */ + if (bus_token == ops->bus_select_token) + return 1; + + return ops && !!(ops->bus_select_mask & busmask); +} +EXPORT_SYMBOL_GPL(msi_lib_irq_domain_select); diff --git a/drivers/irqchip/irq-msi-lib.h b/drivers/irqchip/irq-msi-lib.h new file mode 100644 index 0000000..f0706cc --- /dev/null +++ b/drivers/irqchip/irq-msi-lib.h @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2022 Linutronix GmbH +// Copyright (C) 2022 Intel + +#ifndef _DRIVERS_IRQCHIP_IRQ_MSI_LIB_H +#define _DRIVERS_IRQCHIP_IRQ_MSI_LIB_H + +#include <linux/bits.h> +#include <linux/irqdomain.h> +#include <linux/msi.h> + +int msi_lib_irq_domain_select(struct irq_domain *d, struct irq_fwspec *fwspec, + enum irq_domain_bus_token bus_token); + +bool msi_lib_init_dev_msi_info(struct device *dev, struct irq_domain *domain, + struct irq_domain *real_parent, + struct msi_domain_info *info); + +#endif /* _DRIVERS_IRQCHIP_IRQ_MSI_LIB_H */