bff705950e
Currently we flush the entire dcache at boot within __cpu_setup, but this is unnecessary as the booting protocol demands that the dcache is invalid and off upon entering the kernel. The presence of the cache flush only serves to hide bugs in bootloaders, and is not safe in the presence of SMP. In an SMP boot scenario the CPUs enter coherency outside of the kernel, and the primary CPU enables its caches before bringing up secondary CPUs. Therefore if any secondary CPU has an entry in its cache (in violation of the boot protocol), the primary CPU might snoop it even if the secondary CPU's cache is disabled. The boot-time cache flush only serves to hide a firmware bug, and slows down a cpu boot unnecessarily. This patch removes the unnecessary boot-time cache flush. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> [catalin.marinas@arm.com: make __flush_dcache_all local only] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
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| .. | ||
| boot | ||
| configs | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| mm | ||
| xen | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||