> @@ -613,10 +614,28 @@ ENDPROC(__secondary_switched) > * x0 = SCTLR_EL1 value for turning on the MMU. > * x27 = *virtual* address to jump to upon completion > * > - * other registers depend on the function called upon completion > + * Other registers depend on the function called upon completion. > + * > + * Checks if the selected granule size is supported by the CPU. > + * If it doesn't park the CPU
Nit: "If it isn't, park the CPU." > */ > +#if defined(CONFIG_ARM64_64K_PAGES) > + > +#define id_aa64mmfr0_tgran_shift ID_AA64MMFR0_TGRAN64_SHIFT > +#define id_aa64mmfr0_tgran_on ID_AA64MMFR0_TGRAN64_ON > + > +#else > + > +#define id_aa64mmfr0_tgran_shift ID_AA64MMFR0_TGRAN4_SHIFT > +#define id_aa64mmfr0_tgran_on ID_AA64MMFR0_TGRAN4_ON Any reason for not using upper-case names for the macros? Given they're local you could just call them TGRAN_SHIFT and TRGRAN_ON to make the asm slightly nicer. > + > +#endif > .section ".idmap.text", "ax" > __enable_mmu: > + mrs x1, ID_AA64MMFR0_EL1 > + ubfx x2, x1, #id_aa64mmfr0_tgran_shift, 4 > + cmp x2, #id_aa64mmfr0_tgran_on > + b.ne __no_granule_support > ldr x5, =vectors > msr vbar_el1, x5 > msr ttbr0_el1, x25 // load TTBR0 > @@ -634,3 +653,8 @@ __enable_mmu: > isb > br x27 > ENDPROC(__enable_mmu) > + > +__no_granule_support: > + wfe > + b __no_granule_support > +ENDPROC(__no_granule_support) Other than the above, this loogs fine to me. In future it would be nice if we could somehow signal that these dead CPUs are trapped in the kernel -- we should have some kind of canary mechanism for that. That needn't block this patch, though. Thanks, Mark. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
