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
 32pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 33pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
 34unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
 35						__page_aligned_bss;
 36EXPORT_SYMBOL(empty_zero_page);
 37
 38void __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
 63extern char __init_begin[], __init_end[];
 64
 65void free_initmem(void)
 66{
 67	unsigned long addr;
 68
 69	addr = (unsigned long) &__init_begin;
 70
 71	while (addr < (unsigned long) &__init_end) {
 72		ClearPageReserved(virt_to_page(addr));
 73		init_page_count(virt_to_page(addr));
 74		free_page(addr);
 75		totalram_pages_inc();
 76		addr += PAGE_SIZE;
 77	}
 78
 79	pr_info("Freeing unused kernel memory: %dk freed\n",
 80	((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10);
 81}
 82
 83void pgd_init(unsigned long *p)
 84{
 85	int i;
 86
 87	for (i = 0; i < PTRS_PER_PGD; i++)
 88		p[i] = __pa(invalid_pte_table);
 89}
 90
 91void __init pre_mmu_init(void)
 92{
 93	/*
 94	 * Setup page-table and enable TLB-hardrefill
 95	 */
 96	flush_tlb_all();
 97	pgd_init((unsigned long *)swapper_pg_dir);
 98	TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir);
 99	TLBMISS_HANDLER_SETUP_PGD_KERNEL(swapper_pg_dir);
100
101	/* Setup page mask to 4k */
102	write_mmu_pagemask(0);
103}