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 <cyril@ti.com>
Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Subash Patel <subash.rp@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Cyril Chemparathy
2012-07-21 15:55:04 -04:00
committed by Will Deacon
parent a7fbc0d62a
commit 4756dcbfd3
4 changed files with 37 additions and 8 deletions

View File

@@ -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));