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/smp.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'arch/arm/kernel/smp.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 550d63cef68e..217b755aadd4 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -78,6 +78,13 @@ void __init smp_set_ops(struct smp_operations *ops) smp_ops = *ops; }; +static unsigned long get_arch_pgd(pgd_t *pgd) +{ + phys_addr_t pgdir = virt_to_phys(pgd); + BUG_ON(pgdir & ARCH_PGD_MASK); + return pgdir >> ARCH_PGD_SHIFT; +} + int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) { int ret; @@ -87,8 +94,8 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) * its stack and the page tables. */ secondary_data.stack = task_stack_page(idle) + THREAD_START_SP; - secondary_data.pgdir = virt_to_phys(idmap_pgd); - secondary_data.swapper_pg_dir = virt_to_phys(swapper_pg_dir); + secondary_data.pgdir = get_arch_pgd(idmap_pgd); + secondary_data.swapper_pg_dir = get_arch_pgd(swapper_pg_dir); __cpuc_flush_dcache_area(&secondary_data, sizeof(secondary_data)); outer_clean_range(__pa(&secondary_data), __pa(&secondary_data + 1)); -- cgit v1.2.3