sh: Preliminary support for SH-X2 MMU.
This adds some preliminary support for the SH-X2 MMU, used by
newer SH-4A parts (particularly SH7785).
This MMU implements a 'compat' mode with SH-X MMUs and an
'extended' mode for SH-X2 extended features. Extended features
include additional page sizes (8kB, 4MB, 64MB), as well as the
addition of page execute permissions.
The extended mode attributes are placed in a second data array,
which requires us to switch to 64-bit PTEs when in X2 mode.
With the addition of the exec perms, we also overhaul the mmap
prots somewhat, now that it's possible to handle them more
intelligently.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 27463e2..88e9663 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -235,13 +235,22 @@
config 32BIT
bool "Support 32-bit physical addressing through PMB"
- depends on CPU_SH4A && MMU
+ depends on CPU_SH4A && MMU && (!X2TLB || BROKEN)
default y
help
If you say Y here, physical addressing will be extended to
32-bits through the SH-4A PMB. If this is not set, legacy
29-bit physical addressing will be used.
+config X2TLB
+ bool "Enable extended TLB mode"
+ depends on CPU_SUBTYPE_SH7785 && MMU && EXPERIMENTAL
+ help
+ Selecting this option will enable the extended mode of the SH-X2
+ TLB. For legacy SH-X behaviour and interoperability, say N. For
+ all of the fun new features and a willingless to submit bug reports,
+ say Y.
+
config VSYSCALL
bool "Support vsyscall page"
depends on MMU
@@ -256,16 +265,52 @@
(the default value) say Y.
choice
+ prompt "Kernel page size"
+ default PAGE_SIZE_4KB
+
+config PAGE_SIZE_4KB
+ bool "4kB"
+ help
+ This is the default page size used by all SuperH CPUs.
+
+config PAGE_SIZE_8KB
+ bool "8kB"
+ depends on EXPERIMENTAL && X2TLB
+ help
+ This enables 8kB pages as supported by SH-X2 and later MMUs.
+
+config PAGE_SIZE_64KB
+ bool "64kB"
+ depends on EXPERIMENTAL && CPU_SH4
+ help
+ This enables support for 64kB pages, possible on all SH-4
+ CPUs and later. Highly experimental, not recommended.
+
+endchoice
+
+choice
prompt "HugeTLB page size"
depends on HUGETLB_PAGE && CPU_SH4 && MMU
default HUGETLB_PAGE_SIZE_64K
config HUGETLB_PAGE_SIZE_64K
- bool "64K"
+ bool "64kB"
+
+config HUGETLB_PAGE_SIZE_256K
+ bool "256kB"
+ depends on X2TLB
config HUGETLB_PAGE_SIZE_1MB
bool "1MB"
+config HUGETLB_PAGE_SIZE_4MB
+ bool "4MB"
+ depends on X2TLB
+
+config HUGETLB_PAGE_SIZE_64MB
+ bool "64MB"
+ depends on X2TLB
+
endchoice
source "mm/Kconfig"