From 077ee78e392869e46ae6bdc6ba2a3c4249d0b5e1 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 26 Aug 2020 13:17:02 +0200 Subject: [PATCH] PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable The arch_.*_msi_irq[s] fallbacks are compiled in whether an architecture requires them or not. Architectures which are fully utilizing hierarchical irq domains should never call into that code. It's not only architectures which depend on that by implementing one or more of the weak functions, there is also a bunch of drivers which relies on the weak functions which invoke msi_controller::setup_irq[s] and msi_controller::teardown_irq. Make the architectures and drivers which rely on them select them in Kconfig and if not selected replace them by stub functions which emit a warning and fail the PCI/MSI interrupt allocation. Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20200826112333.992429909@linutronix.de --- arch/ia64/Kconfig | 1 + arch/mips/Kconfig | 1 + arch/powerpc/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/sparc/Kconfig | 1 + arch/x86/Kconfig | 1 + drivers/pci/Kconfig | 3 +++ drivers/pci/controller/Kconfig | 3 +++ drivers/pci/msi.c | 3 ++- include/linux/msi.h | 31 ++++++++++++++++++++++++++----- 10 files changed, 40 insertions(+), 6 deletions(-) diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 5b4ec80bf586..7ff5b3bbf160 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -56,6 +56,7 @@ config IA64 select NEED_DMA_MAP_STATE select NEED_SG_DMA_LENGTH select NUMA if !FLATMEM + select PCI_MSI_ARCH_FALLBACKS default y help The Itanium Processor Family is Intel's 64-bit successor to diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index c95fa3a2484c..3690582eb61f 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -86,6 +86,7 @@ config MIPS select MODULES_USE_ELF_REL if MODULES select MODULES_USE_ELF_RELA if MODULES && 64BIT select PERF_USE_VMALLOC + select PCI_MSI_ARCH_FALLBACKS select RTC_LIB select SYSCTL_EXCEPTION_TRACE select VIRT_TO_BUS diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 65bed1fdeaad..9e66ca1376af 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -246,6 +246,7 @@ config PPC select OLD_SIGACTION if PPC32 select OLD_SIGSUSPEND select PCI_DOMAINS if PCI + select PCI_MSI_ARCH_FALLBACKS select PCI_SYSCALL if PCI select PPC_DAWR if PPC64 select RTC_LIB diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index b29fcc66ec39..63dd5a0aa252 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -185,6 +185,7 @@ config S390 select OLD_SIGSUSPEND3 select PCI_DOMAINS if PCI select PCI_MSI if PCI + select PCI_MSI_ARCH_FALLBACKS select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index efeff2c896a5..21a3239870c0 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -43,6 +43,7 @@ config SPARC select GENERIC_STRNLEN_USER select MODULES_USE_ELF_RELA select PCI_SYSCALL if PCI + select PCI_MSI_ARCH_FALLBACKS select ODD_RT_SIGACTION select OLD_SIGSUSPEND select CPU_NO_EFFICIENT_FFS diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7101ac64bb20..196e0688ec3c 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -225,6 +225,7 @@ config X86 select NEED_SG_DMA_LENGTH select PCI_DOMAINS if PCI select PCI_LOCKLESS_CONFIG if PCI + select PCI_MSI_ARCH_FALLBACKS select PERF_EVENTS select RTC_LIB select RTC_MC146818_LIB diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 4bef5c2bae9f..438a792d2cf7 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -56,6 +56,9 @@ config PCI_MSI_IRQ_DOMAIN depends on PCI_MSI select GENERIC_MSI_IRQ_DOMAIN +config PCI_MSI_ARCH_FALLBACKS + bool + config PCI_QUIRKS default y bool "Enable PCI quirk workarounds" if EXPERT diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig index f18c3725ef80..4a7afbe189f8 100644 --- a/drivers/pci/controller/Kconfig +++ b/drivers/pci/controller/Kconfig @@ -41,6 +41,7 @@ config PCI_TEGRA bool "NVIDIA Tegra PCIe controller" depends on ARCH_TEGRA || COMPILE_TEST depends on PCI_MSI_IRQ_DOMAIN + select PCI_MSI_ARCH_FALLBACKS help Say Y here if you want support for the PCIe host controller found on NVIDIA Tegra SoCs. @@ -67,6 +68,7 @@ config PCIE_RCAR_HOST bool "Renesas R-Car PCIe host controller" depends on ARCH_RENESAS || COMPILE_TEST depends on PCI_MSI_IRQ_DOMAIN + select PCI_MSI_ARCH_FALLBACKS help Say Y here if you want PCIe controller support on R-Car SoCs in host mode. @@ -95,6 +97,7 @@ config PCI_HOST_GENERIC config PCIE_XILINX bool "Xilinx AXI PCIe host bridge support" depends on OF || COMPILE_TEST + select PCI_MSI_ARCH_FALLBACKS help Say 'Y' here if you want kernel to support the Xilinx AXI PCIe Host Bridge driver. diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index a2f00d181016..d52d118979a6 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -58,8 +58,8 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) #define pci_msi_teardown_msi_irqs arch_teardown_msi_irqs #endif +#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS /* Arch hooks */ - int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) { struct msi_controller *chip = dev->bus->msi; @@ -132,6 +132,7 @@ void __weak arch_teardown_msi_irqs(struct pci_dev *dev) { return default_teardown_msi_irqs(dev); } +#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */ static void default_restore_msi_irq(struct pci_dev *dev, int irq) { diff --git a/include/linux/msi.h b/include/linux/msi.h index 0180534b5428..6b584cc4757c 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -193,17 +193,38 @@ void pci_msi_mask_irq(struct irq_data *data); void pci_msi_unmask_irq(struct irq_data *data); /* - * The arch hooks to setup up msi irqs. Those functions are - * implemented as weak symbols so that they /can/ be overriden by - * architecture specific code if needed. + * The arch hooks to setup up msi irqs. Default functions are implemented + * as weak symbols so that they /can/ be overriden by architecture specific + * code if needed. These hooks must be enabled by the architecture or by + * drivers which depend on them via msi_controller based MSI handling. + * + * If CONFIG_PCI_MSI_ARCH_FALLBACKS is not selected they are replaced by + * stubs with warnings. */ +#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc); void arch_teardown_msi_irq(unsigned int irq); int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type); void arch_teardown_msi_irqs(struct pci_dev *dev); -void arch_restore_msi_irqs(struct pci_dev *dev); - void default_teardown_msi_irqs(struct pci_dev *dev); +#else +static inline int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) +{ + WARN_ON_ONCE(1); + return -ENODEV; +} + +static inline void arch_teardown_msi_irqs(struct pci_dev *dev) +{ + WARN_ON_ONCE(1); +} +#endif + +/* + * The restore hooks are still available as they are useful even + * for fully irq domain based setups. Courtesy to XEN/X86. + */ +void arch_restore_msi_irqs(struct pci_dev *dev); void default_restore_msi_irqs(struct pci_dev *dev); struct msi_controller {