On Thu, 31 Jan 2013, Arnd Bergmann wrote: > This is what I think it would look like to do a default platform > with an empty machine descriptor on ARM. It makes the few required > entries in the descriptor optional by using the new irqchip_init() > and clocksource_of_init() functions as defaults, and adds > a fallback for the DT case to customize_machine to probe all > the default devices. > > For the case that CONFIG_MULTIPLATFORM is enabled, it then > adds a machine descriptor that never matches any machine but > is used as a fallback if nothing else matches. > > Signed-off-by: Arnd Bergmann <[email protected]>
Looks sensible. Acked-by: Nicolas Pitre <[email protected]> > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 3e3444e..8ff1d38 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -979,7 +979,6 @@ config ARCH_MULTI_V7 > bool "ARMv7 based platforms (Cortex-A, PJ4, Krait)" > default y > select ARCH_MULTI_V6_V7 > - select ARCH_VEXPRESS > select CPU_V7 > > config ARCH_MULTI_V6_V7 > diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c > index 70f1bde..e6e34ba 100644 > --- a/arch/arm/kernel/devtree.c > +++ b/arch/arm/kernel/devtree.c > @@ -180,6 +180,13 @@ struct machine_desc * __init setup_machine_fdt(unsigned > int dt_phys) > unsigned long dt_root; > const char *model; > > + if (IS_ENABLED(CONFIG_ARCH_MULTIPLATFORM)) { > + DT_MACHINE_START(GENERIC_DT, "Generic DT based system") > + MACHINE_END > + > + mdesc_best = (struct machine_desc *)&__mach_desc_GENERIC_DT; > + } > + > if (!dt_phys) > return NULL; > > @@ -199,7 +206,7 @@ struct machine_desc * __init setup_machine_fdt(unsigned > int dt_phys) > mdesc_score = score; > } > } > - if (!mdesc_best) { > + if (!mdesc_best && !IS_ENABLED(CONFIG_ARCH_MULTIPLATFORM)) { > const char *prop; > long size; > > diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c > index 8e4ef4c..df6f9a1 100644 > --- a/arch/arm/kernel/irq.c > +++ b/arch/arm/kernel/irq.c > @@ -26,6 +26,7 @@ > #include <linux/ioport.h> > #include <linux/interrupt.h> > #include <linux/irq.h> > +#include <linux/irqchip.h> > #include <linux/random.h> > #include <linux/smp.h> > #include <linux/init.h> > @@ -114,7 +115,10 @@ EXPORT_SYMBOL_GPL(set_irq_flags); > > void __init init_IRQ(void) > { > - machine_desc->init_irq(); > + if (machine_desc->init_irq) > + machine_desc->init_irq(); > + else > + irqchip_init(); > } > > #ifdef CONFIG_MULTI_IRQ_HANDLER > diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c > index 3f6cbb2..1d40c9d 100644 > --- a/arch/arm/kernel/setup.c > +++ b/arch/arm/kernel/setup.c > @@ -18,6 +18,7 @@ > #include <linux/bootmem.h> > #include <linux/seq_file.h> > #include <linux/screen_info.h> > +#include <linux/of_platform.h> > #include <linux/init.h> > #include <linux/kexec.h> > #include <linux/of_fdt.h> > @@ -640,9 +641,17 @@ struct screen_info screen_info = { > > static int __init customize_machine(void) > { > - /* customizes platform devices, or adds new ones */ > + /* > + * customizes platform devices, or adds new ones > + * On DT based machines, we fall back to populating the > + * machine from the device tree, if no callback is provided, > + * otherwise we would always need an init_machine callback. > + */ > if (machine_desc->init_machine) > machine_desc->init_machine(); > + else > + of_platform_populate(NULL, of_default_bus_match_table, > + NULL, NULL); > return 0; > } > arch_initcall(customize_machine); > @@ -732,7 +741,7 @@ void __init setup_arch(char **cmdline_p) > > setup_processor(); > mdesc = setup_machine_fdt(__atags_pointer); > - if (!mdesc) > + if (!mdesc && __machine_arch_type != ~0) > mdesc = setup_machine_tags(__atags_pointer, > __machine_arch_type); > machine_desc = mdesc; > machine_name = mdesc->name; > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c > index 955d92d..abff4e9 100644 > --- a/arch/arm/kernel/time.c > +++ b/arch/arm/kernel/time.c > @@ -22,6 +22,7 @@ > #include <linux/errno.h> > #include <linux/profile.h> > #include <linux/timer.h> > +#include <linux/clocksource.h> > #include <linux/irq.h> > > #include <asm/thread_info.h> > @@ -115,6 +116,10 @@ int __init register_persistent_clock(clock_access_fn > read_boot, > > void __init time_init(void) > { > - machine_desc->init_time(); > + if (machine_desc->init_time) > + machine_desc->init_time(); > + else > + clocksource_of_init(); > + > sched_clock_postinit(); > } > diff --git a/drivers/irqchip/irqchip.c b/drivers/irqchip/irqchip.c > index f496afc..c5e7a45 100644 > --- a/drivers/irqchip/irqchip.c > +++ b/drivers/irqchip/irqchip.c > @@ -24,7 +24,13 @@ irqchip_of_match_end __used __section(__irqchip_of_end); > > extern struct of_device_id __irqchip_begin[]; > > +#ifdef CONFIG_IRQCHIP > void __init irqchip_init(void) > { > of_irq_init(__irqchip_begin); > } > +#else > +static inline void irqchip_init(void) > +{ > +} > +#endif > diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h > index 7944f14..b14d224 100644 > --- a/include/linux/clocksource.h > +++ b/include/linux/clocksource.h > @@ -339,6 +339,10 @@ extern void clocksource_of_init(void); > static const struct of_device_id __clksrc_of_table_##name \ > __used __section(__clksrc_of_table) \ > = { .compatible = compat, .data = fn }; > +#else > +static inline void clocksource_of_init(void) > +{ > +} > #endif > > #endif /* _LINUX_CLOCKSOURCE_H */ > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
