diff options
Diffstat (limited to 'arch/csky/mm/init.c')
| -rw-r--r-- | arch/csky/mm/init.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c new file mode 100644 index 000000000..af6271283 --- /dev/null +++ b/arch/csky/mm/init.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include <linux/bug.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/pagemap.h> +#include <linux/ptrace.h> +#include <linux/mman.h> +#include <linux/mm.h> +#include <linux/highmem.h> +#include <linux/memblock.h> +#include <linux/swap.h> +#include <linux/proc_fs.h> +#include <linux/pfn.h> +#include <linux/initrd.h> + +#include <asm/setup.h> +#include <asm/cachectl.h> +#include <asm/dma.h> +#include <asm/pgalloc.h> +#include <asm/mmu_context.h> +#include <asm/sections.h> +#include <asm/tlb.h> + +pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; +pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss; +EXPORT_SYMBOL(invalid_pte_table); +unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] + __page_aligned_bss; +EXPORT_SYMBOL(empty_zero_page); + +#ifdef CONFIG_BLK_DEV_INITRD +static void __init setup_initrd(void) +{ + unsigned long size; + + if (initrd_start >= initrd_end) { + pr_err("initrd not found or empty"); + goto disable; + } + + if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) { + pr_err("initrd extends beyond end of memory"); + goto disable; + } + + size = initrd_end - initrd_start; + + if (memblock_is_region_reserved(__pa(initrd_start), size)) { + pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region", + __pa(initrd_start), size); + goto disable; + } + + memblock_reserve(__pa(initrd_start), size); + + pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n", + (void *)(initrd_start), size); + + initrd_below_start_ok = 1; + + return; + +disable: + initrd_start = initrd_end = 0; + + pr_err(" - disabling initrd\n"); +} +#endif + +void __init mem_init(void) +{ +#ifdef CONFIG_HIGHMEM + unsigned long tmp; + + max_mapnr = highend_pfn; +#else + max_mapnr = max_low_pfn; +#endif + high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); + +#ifdef CONFIG_BLK_DEV_INITRD + setup_initrd(); +#endif + + memblock_free_all(); + +#ifdef CONFIG_HIGHMEM + for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { + struct page *page = pfn_to_page(tmp); + + /* FIXME not sure about */ + if (!memblock_is_reserved(tmp << PAGE_SHIFT)) + free_highmem_page(page); + } +#endif + mem_init_print_info(NULL); +} + +extern char __init_begin[], __init_end[]; + +void free_initmem(void) +{ + unsigned long addr; + + addr = (unsigned long) &__init_begin; + + while (addr < (unsigned long) &__init_end) { + ClearPageReserved(virt_to_page(addr)); + init_page_count(virt_to_page(addr)); + free_page(addr); + totalram_pages_inc(); + addr += PAGE_SIZE; + } + + pr_info("Freeing unused kernel memory: %dk freed\n", + ((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10); +} + +void pgd_init(unsigned long *p) +{ + int i; + + for (i = 0; i < PTRS_PER_PGD; i++) + p[i] = __pa(invalid_pte_table); +} + +void __init pre_mmu_init(void) +{ + /* + * Setup page-table and enable TLB-hardrefill + */ + flush_tlb_all(); + pgd_init((unsigned long *)swapper_pg_dir); + TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir); + TLBMISS_HANDLER_SETUP_PGD_KERNEL(swapper_pg_dir); + + /* Setup page mask to 4k */ + write_mmu_pagemask(0); +} + +void __init fixrange_init(unsigned long start, unsigned long end, + pgd_t *pgd_base) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + int i, j, k; + unsigned long vaddr; + + vaddr = start; + i = pgd_index(vaddr); + j = pud_index(vaddr); + k = pmd_index(vaddr); + pgd = pgd_base + i; + + for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { + pud = (pud_t *)pgd; + for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) { + pmd = (pmd_t *)pud; + for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) { + if (pmd_none(*pmd)) { + pte = (pte_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE); + if (!pte) + panic("%s: Failed to allocate %lu bytes align=%lx\n", + __func__, PAGE_SIZE, + PAGE_SIZE); + + set_pmd(pmd, __pmd(__pa(pte))); + BUG_ON(pte != pte_offset_kernel(pmd, 0)); + } + vaddr += PMD_SIZE; + } + k = 0; + } + j = 0; + } +} + +void __init fixaddr_init(void) +{ + unsigned long vaddr; + + vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK; + fixrange_init(vaddr, vaddr + PMD_SIZE, swapper_pg_dir); +} |