diff options
Diffstat (limited to 'arch/arm64/Kconfig')
| -rw-r--r-- | arch/arm64/Kconfig | 42 |
1 files changed, 37 insertions, 5 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 13b51a0c4e7f..854166422c42 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -173,7 +173,8 @@ config PGTABLE_LEVELS default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42 default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39 - default 4 if ARM64_4K_PAGES && ARM64_VA_BITS_48 + default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47 + default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48 source "init/Kconfig" @@ -363,6 +364,13 @@ config ARM64_4K_PAGES help This feature enables 4KB pages support. +config ARM64_16K_PAGES + bool "16KB" + help + The system will use 16KB pages support. AArch32 emulation + requires applications compiled with 16K (or a multiple of 16K) + aligned segments. + config ARM64_64K_PAGES bool "64KB" help @@ -376,6 +384,7 @@ endchoice choice prompt "Virtual address space size" default ARM64_VA_BITS_39 if ARM64_4K_PAGES + default ARM64_VA_BITS_47 if ARM64_16K_PAGES default ARM64_VA_BITS_42 if ARM64_64K_PAGES help Allows choosing one of multiple possible virtual address @@ -390,6 +399,10 @@ config ARM64_VA_BITS_42 bool "42-bit" depends on ARM64_64K_PAGES +config ARM64_VA_BITS_47 + bool "47-bit" + depends on ARM64_16K_PAGES + config ARM64_VA_BITS_48 bool "48-bit" @@ -399,6 +412,7 @@ config ARM64_VA_BITS int default 39 if ARM64_VA_BITS_39 default 42 if ARM64_VA_BITS_42 + default 47 if ARM64_VA_BITS_47 default 48 if ARM64_VA_BITS_48 config CPU_BIG_ENDIAN @@ -466,7 +480,7 @@ config ARCH_WANT_GENERAL_HUGETLB def_bool y config ARCH_WANT_HUGE_PMD_SHARE - def_bool y if ARM64_4K_PAGES + def_bool y if ARM64_4K_PAGES || ARM64_16K_PAGES config HAVE_ARCH_TRANSPARENT_HUGEPAGE def_bool y @@ -503,7 +517,25 @@ config XEN config FORCE_MAX_ZONEORDER int default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE) + default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE) default "11" + help + The kernel memory allocator divides physically contiguous memory + blocks into "zones", where each zone is a power of two number of + pages. This option selects the largest power of two that the kernel + keeps in the memory allocator. If you need to allocate very large + blocks of physically contiguous memory, then you may need to + increase this value. + + This config option is actually maximum order plus one. For example, + a value of 11 means that the largest free memory block is 2^10 pages. + + We make sure that we can allocate upto a HugePage size for each configuration. + Hence we have : + MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2 + + However for 4K, we choose a higher default value, 11 as opposed to 10, giving us + 4M allocations matching the default size used by generic code. menuconfig ARMV8_DEPRECATED bool "Emulate deprecated/obsolete ARMv8 instructions" @@ -689,9 +721,9 @@ config COMPAT the user helper functions, VFP support and the ptrace interface are handled appropriately by the kernel. - If you also enabled CONFIG_ARM64_64K_PAGES, please be aware that you - will only be able to execute AArch32 binaries that were compiled with - 64k aligned segments. + If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware + that you will only be able to execute AArch32 binaries that were compiled + with page size aligned segments. If you want to execute 32-bit userspace applications, say Y. |