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 <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200826112333.992429909@linutronix.de
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
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
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
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
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
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
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
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.
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.
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.
#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;
{
return default_teardown_msi_irqs(dev);
}
+#endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */
static void default_restore_msi_irq(struct pci_dev *dev, int irq)
{
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 {