swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
Tip revision: bcf876870b95592b52519ed4aafcf9d95999bc9c authored by Linus Torvalds on 02 August 2020, 21:21:45 UTC
Linux 5.8
Linux 5.8
Tip revision: bcf8768
init.c
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 2000 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
*/
#include <linux/bug.h>
#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/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/memblock.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/kcore.h>
#include <linux/initrd.h>
#include <asm/bootinfo.h>
#include <asm/cachectl.h>
#include <asm/cpu.h>
#include <asm/dma.h>
#include <asm/kmap_types.h>
#include <asm/maar.h>
#include <asm/mmu_context.h>
#include <asm/sections.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <asm/fixmap.h>
/*
* We have up to 8 empty zeroed pages so we can map one of the right colour
* when needed. This is necessary only on R4000 / R4400 SC and MC versions
* where we have to avoid VCED / VECI exceptions for good performance at
* any price. 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);
/*
* Not static inline because used by IP27 special magic initialization code
*/
void setup_zero_pages(void)
{
unsigned int order, i;
struct page *page;
if (cpu_has_vce)
order = 3;
else
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;
}
static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot)
{
enum fixed_addresses idx;
unsigned int uninitialized_var(old_mmid);
unsigned long vaddr, flags, entrylo;
unsigned long old_ctx;
pte_t pte;
int tlbidx;
BUG_ON(Page_dcache_dirty(page));
preempt_disable();
pagefault_disable();
idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
idx += in_interrupt() ? FIX_N_COLOURS : 0;
vaddr = __fix_to_virt(FIX_CMAP_END - idx);
pte = mk_pte(page, prot);
#if defined(CONFIG_XPA)
entrylo = pte_to_entrylo(pte.pte_high);
#elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
entrylo = pte.pte_high;
#else
entrylo = pte_to_entrylo(pte_val(pte));
#endif
local_irq_save(flags);
old_ctx = read_c0_entryhi();
write_c0_entryhi(vaddr & (PAGE_MASK << 1));
write_c0_entrylo0(entrylo);
write_c0_entrylo1(entrylo);
if (cpu_has_mmid) {
old_mmid = read_c0_memorymapid();
write_c0_memorymapid(MMID_KERNEL_WIRED);
}
#ifdef CONFIG_XPA
if (cpu_has_xpa) {
entrylo = (pte.pte_low & _PFNX_MASK);
writex_c0_entrylo0(entrylo);
writex_c0_entrylo1(entrylo);
}
#endif
tlbidx = num_wired_entries();
write_c0_wired(tlbidx + 1);
write_c0_index(tlbidx);
mtc0_tlbw_hazard();
tlb_write_indexed();
tlbw_use_hazard();
write_c0_entryhi(old_ctx);
if (cpu_has_mmid)
write_c0_memorymapid(old_mmid);
local_irq_restore(flags);
return (void*) vaddr;
}
void *kmap_coherent(struct page *page, unsigned long addr)
{
return __kmap_pgprot(page, addr, PAGE_KERNEL);
}
void *kmap_noncoherent(struct page *page, unsigned long addr)
{
return __kmap_pgprot(page, addr, PAGE_KERNEL_NC);
}
void kunmap_coherent(void)
{
unsigned int wired;
unsigned long flags, old_ctx;
local_irq_save(flags);
old_ctx = read_c0_entryhi();
wired = num_wired_entries() - 1;
write_c0_wired(wired);
write_c0_index(wired);
write_c0_entryhi(UNIQUE_ENTRYHI(wired));
write_c0_entrylo0(0);
write_c0_entrylo1(0);
mtc0_tlbw_hazard();
tlb_write_indexed();
tlbw_use_hazard();
write_c0_entryhi(old_ctx);
local_irq_restore(flags);
pagefault_enable();
preempt_enable();
}
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);
if (cpu_has_dc_aliases &&
page_mapcount(from) && !Page_dcache_dirty(from)) {
vfrom = kmap_coherent(from, vaddr);
copy_page(vto, vfrom);
kunmap_coherent();
} else {
vfrom = kmap_atomic(from);
copy_page(vto, vfrom);
kunmap_atomic(vfrom);
}
if ((!cpu_has_ic_fills_f_dc) ||
pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
flush_data_cache_page((unsigned long)vto);
kunmap_atomic(vto);
/* Make sure this page is cleared on other CPU's too before using it */
smp_wmb();
}
void copy_to_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr, void *dst, const void *src,
unsigned long len)
{
if (cpu_has_dc_aliases &&
page_mapcount(page) && !Page_dcache_dirty(page)) {
void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(vto, src, len);
kunmap_coherent();
} else {
memcpy(dst, src, len);
if (cpu_has_dc_aliases)
SetPageDcacheDirty(page);
}
if (vma->vm_flags & VM_EXEC)
flush_cache_page(vma, vaddr, page_to_pfn(page));
}
void copy_from_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr, void *dst, const void *src,
unsigned long len)
{
if (cpu_has_dc_aliases &&
page_mapcount(page) && !Page_dcache_dirty(page)) {
void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(dst, vfrom, len);
kunmap_coherent();
} else {
memcpy(dst, src, len);
if (cpu_has_dc_aliases)
SetPageDcacheDirty(page);
}
}
EXPORT_SYMBOL_GPL(copy_from_user_page);
void __init fixrange_init(unsigned long start, unsigned long end,
pgd_t *pgd_base)
{
#ifdef CONFIG_HIGHMEM
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((unsigned long)pte));
BUG_ON(pte != pte_offset_kernel(pmd, 0));
}
vaddr += PMD_SIZE;
}
k = 0;
}
j = 0;
}
#endif
}
struct maar_walk_info {
struct maar_config cfg[16];
unsigned int num_cfg;
};
static int maar_res_walk(unsigned long start_pfn, unsigned long nr_pages,
void *data)
{
struct maar_walk_info *wi = data;
struct maar_config *cfg = &wi->cfg[wi->num_cfg];
unsigned int maar_align;
/* MAAR registers hold physical addresses right shifted by 4 bits */
maar_align = BIT(MIPS_MAAR_ADDR_SHIFT + 4);
/* Fill in the MAAR config entry */
cfg->lower = ALIGN(PFN_PHYS(start_pfn), maar_align);
cfg->upper = ALIGN_DOWN(PFN_PHYS(start_pfn + nr_pages), maar_align) - 1;
cfg->attrs = MIPS_MAAR_S;
/* Ensure we don't overflow the cfg array */
if (!WARN_ON(wi->num_cfg >= ARRAY_SIZE(wi->cfg)))
wi->num_cfg++;
return 0;
}
unsigned __weak platform_maar_init(unsigned num_pairs)
{
unsigned int num_configured;
struct maar_walk_info wi;
wi.num_cfg = 0;
walk_system_ram_range(0, max_pfn, &wi, maar_res_walk);
num_configured = maar_config(wi.cfg, wi.num_cfg, num_pairs);
if (num_configured < wi.num_cfg)
pr_warn("Not enough MAAR pairs (%u) for all memory regions (%u)\n",
num_pairs, wi.num_cfg);
return num_configured;
}
void maar_init(void)
{
unsigned num_maars, used, i;
phys_addr_t lower, upper, attr;
static struct {
struct maar_config cfgs[3];
unsigned used;
} recorded = { { { 0 } }, 0 };
if (!cpu_has_maar)
return;
/* Detect the number of MAARs */
write_c0_maari(~0);
back_to_back_c0_hazard();
num_maars = read_c0_maari() + 1;
/* MAARs should be in pairs */
WARN_ON(num_maars % 2);
/* Set MAARs using values we recorded already */
if (recorded.used) {
used = maar_config(recorded.cfgs, recorded.used, num_maars / 2);
BUG_ON(used != recorded.used);
} else {
/* Configure the required MAARs */
used = platform_maar_init(num_maars / 2);
}
/* Disable any further MAARs */
for (i = (used * 2); i < num_maars; i++) {
write_c0_maari(i);
back_to_back_c0_hazard();
write_c0_maar(0);
back_to_back_c0_hazard();
}
if (recorded.used)
return;
pr_info("MAAR configuration:\n");
for (i = 0; i < num_maars; i += 2) {
write_c0_maari(i);
back_to_back_c0_hazard();
upper = read_c0_maar();
#ifdef CONFIG_XPA
upper |= (phys_addr_t)readx_c0_maar() << MIPS_MAARX_ADDR_SHIFT;
#endif
write_c0_maari(i + 1);
back_to_back_c0_hazard();
lower = read_c0_maar();
#ifdef CONFIG_XPA
lower |= (phys_addr_t)readx_c0_maar() << MIPS_MAARX_ADDR_SHIFT;
#endif
attr = lower & upper;
lower = (lower & MIPS_MAAR_ADDR) << 4;
upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff;
pr_info(" [%d]: ", i / 2);
if ((attr & MIPS_MAAR_V) != MIPS_MAAR_V) {
pr_cont("disabled\n");
continue;
}
pr_cont("%pa-%pa", &lower, &upper);
if (attr & MIPS_MAAR_S)
pr_cont(" speculate");
pr_cont("\n");
/* Record the setup for use on secondary CPUs */
if (used <= ARRAY_SIZE(recorded.cfgs)) {
recorded.cfgs[recorded.used].lower = lower;
recorded.cfgs[recorded.used].upper = upper;
recorded.cfgs[recorded.used].attrs = attr;
recorded.used++;
}
}
}
#ifndef CONFIG_NEED_MULTIPLE_NODES
void __init paging_init(void)
{
unsigned long max_zone_pfns[MAX_NR_ZONES];
pagetable_init();
#ifdef CONFIG_HIGHMEM
kmap_init();
#endif
#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;
#ifdef CONFIG_HIGHMEM
max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
printk(KERN_WARNING "This processor doesn't support highmem."
" %ldk highmem ignored\n",
(highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
}
#endif
free_area_init(max_zone_pfns);
}
#ifdef CONFIG_64BIT
static struct kcore_list kcore_kseg0;
#endif
static inline void __init mem_init_free_highmem(void)
{
#ifdef CONFIG_HIGHMEM
unsigned long tmp;
if (cpu_has_dc_aliases)
return;
for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
struct page *page = pfn_to_page(tmp);
if (!memblock_is_memory(PFN_PHYS(tmp)))
SetPageReserved(page);
else
free_highmem_page(page);
}
#endif
}
void __init mem_init(void)
{
/*
* When _PFN_SHIFT is greater than PAGE_SHIFT we won't have enough PTE
* bits to hold a full 32b physical address on MIPS32 systems.
*/
BUILD_BUG_ON(IS_ENABLED(CONFIG_32BIT) && (_PFN_SHIFT > PAGE_SHIFT));
#ifdef CONFIG_HIGHMEM
#ifdef CONFIG_DISCONTIGMEM
#error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
#endif
max_mapnr = highend_pfn ? highend_pfn : max_low_pfn;
#else
max_mapnr = max_low_pfn;
#endif
high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
maar_init();
memblock_free_all();
setup_zero_pages(); /* Setup zeroed pages. */
mem_init_free_highmem();
mem_init_print_info(NULL);
#ifdef CONFIG_64BIT
if ((unsigned long) &_text > (unsigned long) CKSEG0)
/* The -4 is a hack so that user tools don't have to handle
the overflow. */
kclist_add(&kcore_kseg0, (void *) CKSEG0,
0x80000000 - 4, KCORE_TEXT);
#endif
}
#endif /* !CONFIG_NEED_MULTIPLE_NODES */
void free_init_pages(const char *what, unsigned long begin, unsigned long end)
{
unsigned long pfn;
for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
struct page *page = pfn_to_page(pfn);
void *addr = phys_to_virt(PFN_PHYS(pfn));
memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
free_reserved_page(page);
}
printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
}
void (*free_init_pages_eva)(void *begin, void *end) = NULL;
void __ref free_initmem(void)
{
prom_free_prom_memory();
/*
* Let the platform define a specific function to free the
* init section since EVA may have used any possible mapping
* between virtual and physical addresses.
*/
if (free_init_pages_eva)
free_init_pages_eva((void *)&__init_begin, (void *)&__init_end);
else
free_initmem_default(POISON_FREE_INITMEM);
}
#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(__per_cpu_offset);
static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
{
return node_distance(cpu_to_node(from), cpu_to_node(to));
}
static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
size_t align)
{
return memblock_alloc_try_nid(size, align, __pa(MAX_DMA_ADDRESS),
MEMBLOCK_ALLOC_ACCESSIBLE,
cpu_to_node(cpu));
}
static void __init pcpu_fc_free(void *ptr, size_t size)
{
memblock_free_early(__pa(ptr), size);
}
void __init setup_per_cpu_areas(void)
{
unsigned long delta;
unsigned int cpu;
int rc;
/*
* Always reserve area for module percpu variables. That's
* what the legacy allocator did.
*/
rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
pcpu_cpu_distance,
pcpu_fc_alloc, pcpu_fc_free);
if (rc < 0)
panic("Failed to initialize percpu areas.");
delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
for_each_possible_cpu(cpu)
__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
}
#endif
#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
unsigned long pgd_current[NR_CPUS];
#endif
/*
* 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);
#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);