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>
diff --git a/arch/arm/mm/proc-v7-3level.S b/arch/arm/mm/proc-v7-3level.S
index 58ab747..5ffe195 100644
--- a/arch/arm/mm/proc-v7-3level.S
+++ b/arch/arm/mm/proc-v7-3level.S
@@ -114,6 +114,7 @@
*/
.macro v7_ttb_setup, zero, ttbr0, ttbr1, tmp
ldr \tmp, =swapper_pg_dir @ swapper_pg_dir virtual address
+ mov \tmp, \tmp, lsr #ARCH_PGD_SHIFT
cmp \ttbr1, \tmp @ PHYS_OFFSET > PAGE_OFFSET?
mrc p15, 0, \tmp, c2, c0, 2 @ TTB control register
orr \tmp, \tmp, #TTB_EAE
@@ -128,8 +129,15 @@
*/
orrls \tmp, \tmp, #TTBR1_SIZE @ TTBCR.T1SZ
mcr p15, 0, \tmp, c2, c0, 2 @ TTBCR
+ mov \tmp, \ttbr1, lsr #(32 - ARCH_PGD_SHIFT) @ upper bits
+ mov \ttbr1, \ttbr1, lsl #ARCH_PGD_SHIFT @ lower bits
addls \ttbr1, \ttbr1, #TTBR1_OFFSET
mcrr p15, 1, \ttbr1, \zero, c2 @ load TTBR1
+ mov \tmp, \ttbr0, lsr #(32 - ARCH_PGD_SHIFT) @ upper bits
+ mov \ttbr0, \ttbr0, lsl #ARCH_PGD_SHIFT @ lower bits
+ mcrr p15, 0, \ttbr0, \zero, c2 @ load TTBR0
+ mcrr p15, 1, \ttbr1, \zero, c2 @ load TTBR1
+ mcrr p15, 0, \ttbr0, \zero, c2 @ load TTBR0
.endm
__CPUINIT