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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012 Regents of the University of California
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
*/
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/initrd.h>
#include <linux/swap.h>
#include <linux/sizes.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <asm/fixmap.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include "../kernel/head.h"
unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
__page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);
extern char _start[];
static void __init zone_sizes_init(void)
{
unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
#ifdef CONFIG_ZONE_DMA32
max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G,
(unsigned long) PFN_PHYS(max_low_pfn)));
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
free_area_init_nodes(max_zone_pfns);
}
void setup_zero_page(void)
{
memset((void *)empty_zero_page, 0, PAGE_SIZE);
}
void __init mem_init(void)
{
#ifdef CONFIG_FLATMEM
BUG_ON(!mem_map);
#endif /* CONFIG_FLATMEM */
high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
memblock_free_all();
mem_init_print_info(NULL);
}
#ifdef CONFIG_BLK_DEV_INITRD
static void __init setup_initrd(void)
{
unsigned long size;
if (initrd_start >= initrd_end) {
pr_info("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;
memblock_reserve(__pa(initrd_start), size);
initrd_below_start_ok = 1;
pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
(void *)(initrd_start), size);
return;
disable:
pr_cont(" - disabling initrd\n");
initrd_start = 0;
initrd_end = 0;
}
#endif /* CONFIG_BLK_DEV_INITRD */
static phys_addr_t dtb_early_pa __initdata;
void __init setup_bootmem(void)
{
struct memblock_region *reg;
phys_addr_t mem_size = 0;
phys_addr_t vmlinux_end = __pa(&_end);
phys_addr_t vmlinux_start = __pa(&_start);
/* Find the memory region containing the kernel */
for_each_memblock(memory, reg) {
phys_addr_t end = reg->base + reg->size;
if (reg->base <= vmlinux_end && vmlinux_end <= end) {
mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
/*
* Remove memblock from the end of usable area to the
* end of region
*/
if (reg->base + mem_size < end)
memblock_remove(reg->base + mem_size,
end - reg->base - mem_size);
}
}
BUG_ON(mem_size == 0);
/* Reserve from the start of the kernel to the end of the kernel */
memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
set_max_mapnr(PFN_DOWN(mem_size));
max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
#ifdef CONFIG_BLK_DEV_INITRD
setup_initrd();
#endif /* CONFIG_BLK_DEV_INITRD */
/*
* Avoid using early_init_fdt_reserve_self() since __pa() does
* not work for DTB pointers that are fixmap addresses
*/
memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
early_init_fdt_scan_reserved_mem();
memblock_allow_resize();
memblock_dump_all();
for_each_memblock(memory, reg) {
unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
unsigned long end_pfn = memblock_region_memory_end_pfn(reg);
memblock_set_node(PFN_PHYS(start_pfn),
PFN_PHYS(end_pfn - start_pfn),
&memblock.memory, 0);
}
}
unsigned long va_pa_offset;
EXPORT_SYMBOL(va_pa_offset);
unsigned long pfn_base;
EXPORT_SYMBOL(pfn_base);
void *dtb_early_va;
pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
static bool mmu_enabled;
#define MAX_EARLY_MAPPING_SIZE SZ_128M
pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
{
unsigned long addr = __fix_to_virt(idx);
pte_t *ptep;
BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
ptep = &fixmap_pte[pte_index(addr)];
if (pgprot_val(prot)) {
set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
} else {
pte_clear(&init_mm, addr, ptep);
local_flush_tlb_page(addr);
}
}
static pte_t *__init get_pte_virt(phys_addr_t pa)
{
if (mmu_enabled) {
clear_fixmap(FIX_PTE);
return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
} else {
return (pte_t *)((uintptr_t)pa);
}
}
static phys_addr_t __init alloc_pte(uintptr_t va)
{
/*
* We only create PMD or PGD early mappings so we
* should never reach here with MMU disabled.
*/
BUG_ON(!mmu_enabled);
return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
}
static void __init create_pte_mapping(pte_t *ptep,
uintptr_t va, phys_addr_t pa,
phys_addr_t sz, pgprot_t prot)
{
uintptr_t pte_index = pte_index(va);
BUG_ON(sz != PAGE_SIZE);
if (pte_none(ptep[pte_index]))
ptep[pte_index] = pfn_pte(PFN_DOWN(pa), prot);
}
#ifndef __PAGETABLE_PMD_FOLDED
pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
#if MAX_EARLY_MAPPING_SIZE < PGDIR_SIZE
#define NUM_EARLY_PMDS 1UL
#else
#define NUM_EARLY_PMDS (1UL + MAX_EARLY_MAPPING_SIZE / PGDIR_SIZE)
#endif
pmd_t early_pmd[PTRS_PER_PMD * NUM_EARLY_PMDS] __initdata __aligned(PAGE_SIZE);
static pmd_t *__init get_pmd_virt(phys_addr_t pa)
{
if (mmu_enabled) {
clear_fixmap(FIX_PMD);
return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
} else {
return (pmd_t *)((uintptr_t)pa);
}
}
static phys_addr_t __init alloc_pmd(uintptr_t va)
{
uintptr_t pmd_num;
if (mmu_enabled)
return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
pmd_num = (va - PAGE_OFFSET) >> PGDIR_SHIFT;
BUG_ON(pmd_num >= NUM_EARLY_PMDS);
return (uintptr_t)&early_pmd[pmd_num * PTRS_PER_PMD];
}
static void __init create_pmd_mapping(pmd_t *pmdp,
uintptr_t va, phys_addr_t pa,
phys_addr_t sz, pgprot_t prot)
{
pte_t *ptep;
phys_addr_t pte_phys;
uintptr_t pmd_index = pmd_index(va);
if (sz == PMD_SIZE) {
if (pmd_none(pmdp[pmd_index]))
pmdp[pmd_index] = pfn_pmd(PFN_DOWN(pa), prot);
return;
}
if (pmd_none(pmdp[pmd_index])) {
pte_phys = alloc_pte(va);
pmdp[pmd_index] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
ptep = get_pte_virt(pte_phys);
memset(ptep, 0, PAGE_SIZE);
} else {
pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_index]));
ptep = get_pte_virt(pte_phys);
}
create_pte_mapping(ptep, va, pa, sz, prot);
}
#define pgd_next_t pmd_t
#define alloc_pgd_next(__va) alloc_pmd(__va)
#define get_pgd_next_virt(__pa) get_pmd_virt(__pa)
#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
#define PTE_PARENT_SIZE PMD_SIZE
#define fixmap_pgd_next fixmap_pmd
#else
#define pgd_next_t pte_t
#define alloc_pgd_next(__va) alloc_pte(__va)
#define get_pgd_next_virt(__pa) get_pte_virt(__pa)
#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
#define PTE_PARENT_SIZE PGDIR_SIZE
#define fixmap_pgd_next fixmap_pte
#endif
static void __init create_pgd_mapping(<
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