From 4756dcbfd37819a8359d3c69a22be2ee41666d0f Mon Sep 17 00:00:00 2001 From: Cyril Chemparathy Date: Sat, 21 Jul 2012 15:55:04 -0400 Subject: ARM: LPAE: accomodate >32-bit addresses for page table base This patch redefines the early boot time use of the R4 register to steal a few low order bits (ARCH_PGD_SHIFT bits) on LPAE systems. This allows for up to 38-bit physical addresses. Signed-off-by: Cyril Chemparathy Signed-off-by: Vitaly Andrianov Acked-by: Nicolas Pitre Tested-by: Santosh Shilimkar Tested-by: Subash Patel Signed-off-by: Will Deacon --- arch/arm/kernel/head.S | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'arch/arm/kernel/head.S') diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 8bac553fe213..45e8935cae4e 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -156,7 +156,7 @@ ENDPROC(stext) * * Returns: * r0, r3, r5-r7 corrupted - * r4 = physical page table address + * r4 = page table (see ARCH_PGD_SHIFT in asm/memory.h) */ __create_page_tables: pgtbl r4, r8 @ page table address @@ -331,6 +331,7 @@ __create_page_tables: #endif #ifdef CONFIG_ARM_LPAE sub r4, r4, #0x1000 @ point to the PGD table + mov r4, r4, lsr #ARCH_PGD_SHIFT #endif mov pc, lr ENDPROC(__create_page_tables) @@ -408,7 +409,7 @@ __secondary_data: * r0 = cp#15 control register * r1 = machine ID * r2 = atags or dtb pointer - * r4 = page table pointer + * r4 = page table (see ARCH_PGD_SHIFT in asm/memory.h) * r9 = processor ID * r13 = *virtual* address to jump to upon completion */ @@ -427,10 +428,7 @@ __enable_mmu: #ifdef CONFIG_CPU_ICACHE_DISABLE bic r0, r0, #CR_I #endif -#ifdef CONFIG_ARM_LPAE - mov r5, #0 - mcrr p15, 0, r4, r5, c2 @ load TTBR0 -#else +#ifndef CONFIG_ARM_LPAE mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \ domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \ domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \ -- cgit