diff options
Diffstat (limited to 'arch/loongarch/mm/init.c')
| -rw-r--r-- | arch/loongarch/mm/init.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c index 0532ed5ba43d..080061793c85 100644 --- a/arch/loongarch/mm/init.c +++ b/arch/loongarch/mm/init.c @@ -152,6 +152,70 @@ EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); #endif #endif +static pte_t *fixmap_pte(unsigned long addr) +{ + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + + pgd = pgd_offset_k(addr); + p4d = p4d_offset(pgd, addr); + + if (pgd_none(*pgd)) { + pud_t *new __maybe_unused; + + new = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); + pgd_populate(&init_mm, pgd, new); +#ifndef __PAGETABLE_PUD_FOLDED + pud_init((unsigned long)new, (unsigned long)invalid_pmd_table); +#endif + } + + pud = pud_offset(p4d, addr); + if (pud_none(*pud)) { + pmd_t *new __maybe_unused; + + new = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); + pud_populate(&init_mm, pud, new); +#ifndef __PAGETABLE_PMD_FOLDED + pmd_init((unsigned long)new, (unsigned long)invalid_pte_table); +#endif + } + + pmd = pmd_offset(pud, addr); + if (pmd_none(*pmd)) { + pte_t *new __maybe_unused; + + new = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); + pmd_populate_kernel(&init_mm, pmd, new); + } + + return pte_offset_kernel(pmd, addr); +} + +void __init __set_fixmap(enum fixed_addresses idx, + phys_addr_t phys, pgprot_t flags) +{ + unsigned long addr = __fix_to_virt(idx); + pte_t *ptep; + + BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); + + ptep = fixmap_pte(addr); + if (!pte_none(*ptep)) { + pte_ERROR(*ptep); + return; + } + + if (pgprot_val(flags)) + set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags)); + else { + pte_clear(&init_mm, addr, ptep); + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + } +} + /* * Align swapper_pg_dir in to 64K, allows its address to be loaded * with a single LUI instruction in the TLB handlers. If we used |