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| author | Steve Capper <steve.capper@arm.com> | 2019-08-07 16:55:22 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2019-08-09 11:17:26 +0100 |
| commit | b6d00d47e81a49f6cf462518c10408f37a3e6785 (patch) | |
| tree | f84df6281b176ab0f3c2fea47d8b9ef233f15b6a /arch/arm64/mm | |
| parent | ce3aaed87344c83c77135f80e7b76e1da9c92ee6 (diff) | |
| download | linux-stable-b6d00d47e81a49f6cf462518c10408f37a3e6785.tar.gz linux-stable-b6d00d47e81a49f6cf462518c10408f37a3e6785.tar.bz2 linux-stable-b6d00d47e81a49f6cf462518c10408f37a3e6785.zip | |
arm64: mm: Introduce 52-bit Kernel VAs
Most of the machinery is now in place to enable 52-bit kernel VAs that
are detectable at boot time.
This patch adds a Kconfig option for 52-bit user and kernel addresses
and plumbs in the requisite CONFIG_ macros as well as sets TCR.T1SZ,
physvirt_offset and vmemmap at early boot.
To simplify things this patch also removes the 52-bit user/48-bit kernel
kconfig option.
Signed-off-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/init.c | 10 | ||||
| -rw-r--r-- | arch/arm64/mm/proc.S | 3 |
2 files changed, 12 insertions, 1 deletions
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 2940221e5519..531c497c5758 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -326,6 +326,16 @@ void __init arm64_memblock_init(void) vmemmap = ((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT)); /* + * If we are running with a 52-bit kernel VA config on a system that + * does not support it, we have to offset our vmemmap and physvirt_offset + * s.t. we avoid the 52-bit portion of the direct linear map + */ + if (IS_ENABLED(CONFIG_ARM64_VA_BITS_52) && (vabits_actual != 52)) { + vmemmap += (_PAGE_OFFSET(48) - _PAGE_OFFSET(52)) >> PAGE_SHIFT; + physvirt_offset = PHYS_OFFSET - _PAGE_OFFSET(48); + } + + /* * Remove the memory that we will not be able to cover with the * linear mapping. Take care not to clip the kernel which may be * high in memory. diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 8d289ff7584d..8b021c5c0884 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -438,10 +438,11 @@ ENTRY(__cpu_setup) TCR_TBI0 | TCR_A1 | TCR_KASAN_FLAGS tcr_clear_errata_bits x10, x9, x5 -#ifdef CONFIG_ARM64_USER_VA_BITS_52 +#ifdef CONFIG_ARM64_VA_BITS_52 ldr_l x9, vabits_user sub x9, xzr, x9 add x9, x9, #64 + tcr_set_t1sz x10, x9 #else ldr_l x9, idmap_t0sz #endif |