diff options
| author | Vineet Gupta <vgupta@synopsys.com> | 2014-07-08 15:13:47 +0200 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2015-10-17 14:18:18 +0200 |
| commit | fe6c1b8611aa3a79a937a5e3b85a16576b6ad159 (patch) | |
| tree | 48a4677d99954f7abd084be740fbd9457ca190c7 /arch/arc/Kconfig | |
| parent | Documentation/features/vm: pte_special now supported by ARC (diff) | |
| download | linux-fe6c1b8611aa3a79a937a5e3b85a16576b6ad159.tar.xz linux-fe6c1b8611aa3a79a937a5e3b85a16576b6ad159.zip | |
ARCv2: mm: THP support
MMUv4 in HS38x cores supports Super Pages which are basis for Linux THP
support.
Normal and Super pages can co-exist (ofcourse not overlap) in TLB with a
new bit "SZ" in TLB page desciptor to distinguish between them.
Super Page size is configurable in hardware (4K to 16M), but fixed once
RTL builds.
The exact THP size a Linx configuration will support is a function of:
- MMU page size (typical 8K, RTL fixed)
- software page walker address split between PGD:PTE:PFN (typical
11:8:13, but can be changed with 1 line)
So for above default, THP size supported is 8K * 256 = 2M
Default Page Walker is 2 levels, PGD:PTE:PFN, which in THP regime
reduces to 1 level (as PTE is folded into PGD and canonically referred
to as PMD).
Thus thp PMD accessors are implemented in terms of PTE (just like sparc)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/Kconfig')
| -rw-r--r-- | arch/arc/Kconfig | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 78c0621d5819..5912006391ed 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -76,6 +76,10 @@ config STACKTRACE_SUPPORT config HAVE_LATENCYTOP_SUPPORT def_bool y +config HAVE_ARCH_TRANSPARENT_HUGEPAGE + def_bool y + depends on ARC_MMU_V4 + source "init/Kconfig" source "kernel/Kconfig.freezer" |