Commit 294064f5 authored Jan 09, 2012 by Catalin Marinas Committed by Russell King Jan 13, 2012

ARM: 7275/1: LPAE: Check the CPU support for the long descriptor format



This patch adds a check for the presence of the LPAE feature during the
CPU initialisation. If not present, it reports an error when
CONFIG_DEBUG_LL is enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

parent e37051dc

arch/arm/kernel/head.S

+8 −0

Original line number	Diff line number	Diff line
		@@ -99,6 +99,14 @@ ENTRY(stext)
		THUMB( it eq ) @ force fixup-able long branch encoding
		beq __error_p @ yes, error 'p'

		#ifdef CONFIG_ARM_LPAE
		mrc p15, 0, r3, c0, c1, 4 @ read ID_MMFR0
		and r3, r3, #0xf @ extract VMSA support
		cmp r3, #5 @ long-descriptor translation table format?
		THUMB( it lo ) @ force fixup-able long branch encoding
		blo __error_p @ only classic page table format
		#endif

		#ifndef CONFIG_XIP_KERNEL
		adr r3, 2f
		ldmia r3, {r4, r8}