On Tuesday 28 October 2014 20:58:48 Kevin Cernekee wrote: > > +#ifdef CONFIG_RAW_IRQ_ACCESSORS > + > +#ifndef irq_reg_writel > +# define irq_reg_writel(val, addr) __raw_writel(val, addr) > +#endif > +#ifndef irq_reg_readl > +# define irq_reg_readl(addr) __raw_readl(addr) > +#endif > + > +#else > + No, this is just wrong: registers almost always have a fixed endianess indenpent of CPU endianess, so if you use __raw_writel, it will be broken on one or the other. If you have a machine that uses big-endian registers in the interrupt controller, you need to find a way to use the correct accessors (e.g. iowrite32be) and use them independent of what endianess the CPU is running. As this code is being used on all sorts of platforms, you can't assume that they all use the same endianess, which makes it rather tricky. As the first step, you can probably introduce a new Kconfig symbol GENERIC_IRQ_CHIP_BE, and then make that mutually exclusive with the existing users that all use little-endian registers: #if defined(CONFIG_GENERIC_IRQ_CHIP) && !defined(CONFIG_GENERIC_IRQ_CHIP_BE) #define irq_reg_writel(val, addr) writel(val, addr) #else if defined(CONFIG_GENERIC_IRQ_CHIP_BE) && !defined(CONFIG_GENERIC_IRQ_CHIP) #define irq_reg_writel(val, addr) iowrite32be(val, addr) #else /* provoke a compile error when this is used */ #define irq_reg_writel(val, addr) irq_reg_writel_unknown_endian(val, addr) #endif and --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -1,5 +1,6 @@ obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devres.o +obj-$(CONFIG_GENERIC_IRQ_CHIP_BE) += generic-chip.o obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o Note that you might also have a case where you have more than one generic irqchip driver built into the kernel, which require different endianess. We can't really support that case without changing the generic-chip implementation. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
