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Diffstat (limited to '')
| -rw-r--r-- | arch/loongarch/mm/init.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c new file mode 100644 index 000000000000..080061793c85 --- /dev/null +++ b/arch/loongarch/mm/init.c @@ -0,0 +1,237 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include <linux/init.h> +#include <linux/export.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/smp.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/pagemap.h> +#include <linux/memblock.h> +#include <linux/memremap.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/highmem.h> +#include <linux/swap.h> +#include <linux/proc_fs.h> +#include <linux/pfn.h> +#include <linux/hardirq.h> +#include <linux/gfp.h> +#include <linux/initrd.h> +#include <linux/mmzone.h> + +#include <asm/asm-offsets.h> +#include <asm/bootinfo.h> +#include <asm/cpu.h> +#include <asm/dma.h> +#include <asm/mmu_context.h> +#include <asm/sections.h> +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/tlb.h> + +/* + * We have up to 8 empty zeroed pages so we can map one of the right colour + * when needed. Since page is never written to after the initialization we + * don't have to care about aliases on other CPUs. + */ +unsigned long empty_zero_page, zero_page_mask; +EXPORT_SYMBOL_GPL(empty_zero_page); +EXPORT_SYMBOL(zero_page_mask); + +void setup_zero_pages(void) +{ + unsigned int order, i; + struct page *page; + + order = 0; + + empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); + if (!empty_zero_page) + panic("Oh boy, that early out of memory?"); + + page = virt_to_page((void *)empty_zero_page); + split_page(page, order); + for (i = 0; i < (1 << order); i++, page++) + mark_page_reserved(page); + + zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; +} + +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + void *vfrom, *vto; + + vto = kmap_atomic(to); + vfrom = kmap_atomic(from); + copy_page(vto, vfrom); + kunmap_atomic(vfrom); + kunmap_atomic(vto); + /* Make sure this page is cleared on other CPU's too before using it */ + smp_wmb(); +} + +int __ref page_is_ram(unsigned long pfn) +{ + unsigned long addr = PFN_PHYS(pfn); + + return memblock_is_memory(addr) && !memblock_is_reserved(addr); +} + +#ifndef CONFIG_NUMA +void __init paging_init(void) +{ + unsigned long max_zone_pfns[MAX_NR_ZONES]; + +#ifdef CONFIG_ZONE_DMA + max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; +#endif +#ifdef CONFIG_ZONE_DMA32 + max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; +#endif + max_zone_pfns[ZONE_NORMAL] = max_low_pfn; + + free_area_init(max_zone_pfns); +} + +void __init mem_init(void) +{ + max_mapnr = max_low_pfn; + high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); + + memblock_free_all(); + setup_zero_pages(); /* Setup zeroed pages. */ +} +#endif /* !CONFIG_NUMA */ + +void __ref free_initmem(void) +{ + free_initmem_default(POISON_FREE_INITMEM); +} + +#ifdef CONFIG_MEMORY_HOTPLUG +int arch_add_memory(int nid, u64 start, u64 size, struct mhp_params *params) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + ret = __add_pages(nid, start_pfn, nr_pages, params); + + if (ret) + pr_warn("%s: Problem encountered in __add_pages() as ret=%d\n", + __func__, ret); + + return ret; +} + +void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct page *page = pfn_to_page(start_pfn); + + /* With altmap the first mapped page is offset from @start */ + if (altmap) + page += vmem_altmap_offset(altmap); + __remove_pages(start_pfn, nr_pages, altmap); +} + +#ifdef CONFIG_NUMA +int memory_add_physaddr_to_nid(u64 start) +{ + return pa_to_nid(start); +} +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 + * __aligned(64K), its size would get rounded up to the alignment + * size, and waste space. So we place it in its own section and align + * it in the linker script. + */ +pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(".bss..swapper_pg_dir"); + +pgd_t invalid_pg_dir[_PTRS_PER_PGD] __page_aligned_bss; +#ifndef __PAGETABLE_PUD_FOLDED +pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss; +#endif +#ifndef __PAGETABLE_PMD_FOLDED +pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss; +EXPORT_SYMBOL_GPL(invalid_pmd_table); +#endif +pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss; +EXPORT_SYMBOL(invalid_pte_table); |