On 2014-1-17 22:04, Arnd Bergmann wrote: > On Friday 17 January 2014, Hanjun Guo wrote: >> +++ b/arch/arm64/pci/Makefile >> @@ -0,0 +1 @@ >> +obj-y += pci.o >> diff --git a/arch/arm64/pci/pci.c b/arch/arm64/pci/pci.c >> new file mode 100644 >> index 0000000..4e46790 >> --- /dev/null >> +++ b/arch/arm64/pci/pci.c >> @@ -0,0 +1,33 @@ >> +#include <linux/acpi.h> >> +#include <linux/types.h> >> +#include <linux/kernel.h> >> +#include <linux/pci.h> >> + >> +/** >> + * raw_pci_read - Platform-specific PCI config space access. >> + * >> + * Default empty implementation. Replace with an architecture-specific setup >> + * routine, if necessary. >> + */ >> +int __weak raw_pci_read(unsigned int domain, unsigned int bus, >> + unsigned int devfn, int reg, int len, u32 *val) >> +{ >> + return -EINVAL; >> +} >> + >> +int __weak raw_pci_write(unsigned int domain, unsigned int bus, >> + unsigned int devfn, int reg, int len, u32 val) >> +{ >> + return -EINVAL; >> +} > > I'd rather not see __weak functions here. Just provide them unconditionally > so that we can add a proper implementation when needed. You could also > define these as 'static inline' in a header file to keep them from consuming > space in the object code. Ok, I will remove __weak in next version. > >> diff --git a/drivers/acpi/plat/arm-core.c b/drivers/acpi/plat/arm-core.c >> index 3c8521d..1835b21 100644 >> --- a/drivers/acpi/plat/arm-core.c >> +++ b/drivers/acpi/plat/arm-core.c >> @@ -100,6 +100,25 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq) >> } >> EXPORT_SYMBOL_GPL(acpi_gsi_to_irq); >> >> +int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi) >> +{ >> + return -1; >> +} >> + >> +int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base) >> +{ >> + /* TBD */ >> + return -EINVAL; >> +} >> +EXPORT_SYMBOL(acpi_register_ioapic); >> + >> +int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base) >> +{ >> + /* TBD */ >> + return -EINVAL; >> +} >> +EXPORT_SYMBOL(acpi_unregister_ioapic); >> + > > My feeling is that these are better handled in the ACPI code by not > calling them on architectures that have no ISA or no IOAPIC support. > > We have configuration symbols for both, so you don't have to make > it depend on CONFIG_ARM64 or CONFIG_X86. Do you mean introduce a stub function when there is no ISA support? acpi_register_ioapic()/acpi_unregister_ioapic() will be used for IOAPIC hotplug and GIC distributor is something like IOAPIC on x86, so I think these two functions can be reserved for future use. Thanks Hanjun -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html