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| author |   Ard Biesheuvel <ardb@kernel.org> | 2022-06-24 17:06:33 +0200 |
|---|---|---|
| committer |   Will Deacon <will@kernel.org> | 2022-06-24 17:18:09 +0100 |
| commit | e8d13cced5c5038cc93de9561cf2cb4f22205061 (patch) | |
| tree | 7277fb3e279b3243224508328f57790bd72b32dd /arch/arm64/mm/mmu.c | |
| parent | arm64: mm: make vabits_actual a build time constant if possible (diff) | |
| download | linux-dev-e8d13cced5c5038cc93de9561cf2cb4f22205061.tar.xz linux-dev-e8d13cced5c5038cc93de9561cf2cb4f22205061.zip | |
arm64: head: move assignment of idmap_t0sz to C code
Setting idmap_t0sz involves fiddling with the caches if done with the
MMU off. Since we will be creating an initial ID map with the MMU and
caches off, and the permanent ID map with the MMU and caches on, let's
move this assignment of idmap_t0sz out of the startup code, and replace
it with a macro that simply issues the three instructions needed to
calculate the value wherever it is needed before the MMU is turned on.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20220624150651.1358849-4-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/mm/mmu.c')
| -rw-r--r-- | arch/arm64/mm/mmu.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 88b4177254a0..9b4fc78f7a4d 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -43,7 +43,7 @@ #define NO_CONT_MAPPINGS BIT(1) #define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */ -u64 idmap_t0sz = TCR_T0SZ(VA_BITS_MIN); +int idmap_t0sz __ro_after_init; u64 idmap_ptrs_per_pgd = PTRS_PER_PGD; #if VA_BITS > 48 @@ -771,6 +771,8 @@ void __init paging_init(void) { pgd_t *pgdp = pgd_set_fixmap(__pa_symbol(swapper_pg_dir)); + idmap_t0sz = 63UL - __fls(__pa_symbol(_end) | GENMASK(VA_BITS_MIN - 1, 0)); + map_kernel(pgdp); map_mem(pgdp); |