This feature was partially implemented long time ago. All cpus load
swapper_pg_dir into TTBR1 since commit d427958a46af24f75d0017c45eadd172273bbf33
("ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7").
But TTBRx split is never been enabled in TTBCR.This patch enables TTBRx split for 2Gb/2Gb and 1Gb/3Gb combinations. Area covered by TTBR0 must be power of two, thus 3Gb/1Gb mode is unsupported. Signed-off-by: Konstantin Khlebnikov <[email protected]> --- arch/arm/include/asm/pgtable-2level-hwdef.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/arm/include/asm/pgtable-2level-hwdef.h b/arch/arm/include/asm/pgtable-2level-hwdef.h index c2ed1fa..605652c 100644 --- a/arch/arm/include/asm/pgtable-2level-hwdef.h +++ b/arch/arm/include/asm/pgtable-2level-hwdef.h @@ -90,6 +90,19 @@ #define PHYS_MASK (~0UL) +/* + * TTBR0/TTBR1 split (PAGE_OFFSET): + * 0x40000000: TTBCR.N = 2 + * 0x80000000: TTBCR.N = 1 + * 0xc0000000: TTBCR.N = 0 (not used) + */ + +#ifdef CONFIG_VMSPLIT_1G +#define TTBR1_SIZE 2 +#elif defined CONFIG_VMSPLIT_2G +#define TTBR1_SIZE 1 +#elif defined CONFIG_VMSPLIT_3G #define TTBR1_SIZE 0 +#endif #endif -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
