1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #include <linux/bug.h> 5 #include <linux/module.h> 6 #include <linux/init.h> 7 #include <linux/signal.h> 8 #include <linux/sched.h> 9 #include <linux/kernel.h> 10 #include <linux/errno.h> 11 #include <linux/string.h> 12 #include <linux/types.h> 13 #include <linux/pagemap.h> 14 #include <linux/ptrace.h> 15 #include <linux/mman.h> 16 #include <linux/mm.h> 17 #include <linux/highmem.h> 18 #include <linux/memblock.h> 19 #include <linux/swap.h> 20 #include <linux/proc_fs.h> 21 #include <linux/pfn.h> 22 23 #include <asm/setup.h> 24 #include <asm/cachectl.h> 25 #include <asm/dma.h> 26 #include <asm/pgtable.h> 27 #include <asm/pgalloc.h> 28 #include <asm/mmu_context.h> 29 #include <asm/sections.h> 30 #include <asm/tlb.h> 31 32 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 33 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss; 34 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] 35 __page_aligned_bss; 36 EXPORT_SYMBOL(empty_zero_page); 37 38 void __init mem_init(void) 39 { 40 #ifdef CONFIG_HIGHMEM 41 unsigned long tmp; 42 43 max_mapnr = highend_pfn; 44 #else 45 max_mapnr = max_low_pfn; 46 #endif 47 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 48 49 memblock_free_all(); 50 51 #ifdef CONFIG_HIGHMEM 52 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 53 struct page *page = pfn_to_page(tmp); 54 55 /* FIXME not sure about */ 56 if (!memblock_is_reserved(tmp << PAGE_SHIFT)) 57 free_highmem_page(page); 58 } 59 #endif 60 mem_init_print_info(NULL); 61 } 62 63 #ifdef CONFIG_BLK_DEV_INITRD 64 void free_initrd_mem(unsigned long start, unsigned long end) 65 { 66 if (start < end) 67 pr_info("Freeing initrd memory: %ldk freed\n", 68 (end - start) >> 10); 69 70 for (; start < end; start += PAGE_SIZE) { 71 ClearPageReserved(virt_to_page(start)); 72 init_page_count(virt_to_page(start)); 73 free_page(start); 74 totalram_pages_inc(); 75 } 76 } 77 #endif 78 79 extern char __init_begin[], __init_end[]; 80 81 void free_initmem(void) 82 { 83 unsigned long addr; 84 85 addr = (unsigned long) &__init_begin; 86 87 while (addr < (unsigned long) &__init_end) { 88 ClearPageReserved(virt_to_page(addr)); 89 init_page_count(virt_to_page(addr)); 90 free_page(addr); 91 totalram_pages_inc(); 92 addr += PAGE_SIZE; 93 } 94 95 pr_info("Freeing unused kernel memory: %dk freed\n", 96 ((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10); 97 } 98 99 void pgd_init(unsigned long *p) 100 { 101 int i; 102 103 for (i = 0; i < PTRS_PER_PGD; i++) 104 p[i] = __pa(invalid_pte_table); 105 } 106 107 void __init pre_mmu_init(void) 108 { 109 /* 110 * Setup page-table and enable TLB-hardrefill 111 */ 112 flush_tlb_all(); 113 pgd_init((unsigned long *)swapper_pg_dir); 114 TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir); 115 TLBMISS_HANDLER_SETUP_PGD_KERNEL(swapper_pg_dir); 116 117 /* Setup page mask to 4k */ 118 write_mmu_pagemask(0); 119 } 120