diff options
Diffstat (limited to 'arch/arm/mm/nommu.c')
| -rw-r--r-- | arch/arm/mm/nommu.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c index c42debaded95..c415f3859b20 100644 --- a/arch/arm/mm/nommu.c +++ b/arch/arm/mm/nommu.c @@ -21,11 +21,19 @@ #include <asm/cputype.h> #include <asm/mpu.h> #include <asm/procinfo.h> +#include <asm/idmap.h> #include "mm.h" unsigned long vectors_base; +/* + * empty_zero_page is a special page that is used for + * zero-initialized data and COW. + */ +struct page *empty_zero_page; +EXPORT_SYMBOL(empty_zero_page); + #ifdef CONFIG_ARM_MPU struct mpu_rgn_info mpu_rgn_info; #endif @@ -148,9 +156,21 @@ void __init adjust_lowmem_bounds(void) */ void __init paging_init(const struct machine_desc *mdesc) { + void *zero_page; + early_trap_init((void *)vectors_base); mpu_setup(); + + /* allocate the zero page. */ + zero_page = (void *)memblock_alloc(PAGE_SIZE, PAGE_SIZE); + if (!zero_page) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", + __func__, PAGE_SIZE, PAGE_SIZE); + bootmem_init(); + + empty_zero_page = virt_to_page(zero_page); + flush_dcache_page(empty_zero_page); } /* @@ -160,6 +180,12 @@ void setup_mm_for_reboot(void) { } +void flush_dcache_folio(struct folio *folio) +{ + __cpuc_flush_dcache_area(folio_address(folio), folio_size(folio)); +} +EXPORT_SYMBOL(flush_dcache_folio); + void flush_dcache_page(struct page *page) { __cpuc_flush_dcache_area(page_address(page), PAGE_SIZE); |