160 lines
3.4 KiB
C
160 lines
3.4 KiB
C
/*
|
|
* linux/arch/unicore32/kernel/hibernate.c
|
|
*
|
|
* Code specific to PKUnity SoC and UniCore ISA
|
|
*
|
|
* Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
|
|
* Copyright (C) 2001-2010 Guan Xuetao
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/suspend.h>
|
|
#include <linux/bootmem.h>
|
|
|
|
#include <asm/page.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/suspend.h>
|
|
|
|
#include "mach/pm.h"
|
|
|
|
/* Pointer to the temporary resume page tables */
|
|
pgd_t *resume_pg_dir;
|
|
|
|
struct swsusp_arch_regs swsusp_arch_regs_cpu0;
|
|
|
|
/*
|
|
* Create a middle page table on a resume-safe page and put a pointer to it in
|
|
* the given global directory entry. This only returns the gd entry
|
|
* in non-PAE compilation mode, since the middle layer is folded.
|
|
*/
|
|
static pmd_t *resume_one_md_table_init(pgd_t *pgd)
|
|
{
|
|
pud_t *pud;
|
|
pmd_t *pmd_table;
|
|
|
|
pud = pud_offset(pgd, 0);
|
|
pmd_table = pmd_offset(pud, 0);
|
|
|
|
return pmd_table;
|
|
}
|
|
|
|
/*
|
|
* Create a page table on a resume-safe page and place a pointer to it in
|
|
* a middle page directory entry.
|
|
*/
|
|
static pte_t *resume_one_page_table_init(pmd_t *pmd)
|
|
{
|
|
if (pmd_none(*pmd)) {
|
|
pte_t *page_table = (pte_t *)get_safe_page(GFP_ATOMIC);
|
|
if (!page_table)
|
|
return NULL;
|
|
|
|
set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_KERNEL_TABLE));
|
|
|
|
BUG_ON(page_table != pte_offset_kernel(pmd, 0));
|
|
|
|
return page_table;
|
|
}
|
|
|
|
return pte_offset_kernel(pmd, 0);
|
|
}
|
|
|
|
/*
|
|
* This maps the physical memory to kernel virtual address space, a total
|
|
* of max_low_pfn pages, by creating page tables starting from address
|
|
* PAGE_OFFSET. The page tables are allocated out of resume-safe pages.
|
|
*/
|
|
static int resume_physical_mapping_init(pgd_t *pgd_base)
|
|
{
|
|
unsigned long pfn;
|
|
pgd_t *pgd;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
int pgd_idx, pmd_idx;
|
|
|
|
pgd_idx = pgd_index(PAGE_OFFSET);
|
|
pgd = pgd_base + pgd_idx;
|
|
pfn = 0;
|
|
|
|
for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) {
|
|
pmd = resume_one_md_table_init(pgd);
|
|
if (!pmd)
|
|
return -ENOMEM;
|
|
|
|
if (pfn >= max_low_pfn)
|
|
continue;
|
|
|
|
for (pmd_idx = 0; pmd_idx < PTRS_PER_PMD; pmd++, pmd_idx++) {
|
|
pte_t *max_pte;
|
|
|
|
if (pfn >= max_low_pfn)
|
|
break;
|
|
|
|
/* Map with normal page tables.
|
|
* NOTE: We can mark everything as executable here
|
|
*/
|
|
pte = resume_one_page_table_init(pmd);
|
|
if (!pte)
|
|
return -ENOMEM;
|
|
|
|
max_pte = pte + PTRS_PER_PTE;
|
|
for (; pte < max_pte; pte++, pfn++) {
|
|
if (pfn >= max_low_pfn)
|
|
break;
|
|
|
|
set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC));
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline void resume_init_first_level_page_table(pgd_t *pg_dir)
|
|
{
|
|
}
|
|
|
|
int swsusp_arch_resume(void)
|
|
{
|
|
int error;
|
|
|
|
resume_pg_dir = (pgd_t *)get_safe_page(GFP_ATOMIC);
|
|
if (!resume_pg_dir)
|
|
return -ENOMEM;
|
|
|
|
resume_init_first_level_page_table(resume_pg_dir);
|
|
error = resume_physical_mapping_init(resume_pg_dir);
|
|
if (error)
|
|
return error;
|
|
|
|
/* We have got enough memory and from now on we cannot recover */
|
|
restore_image(resume_pg_dir, restore_pblist);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* pfn_is_nosave - check if given pfn is in the 'nosave' section
|
|
*/
|
|
|
|
int pfn_is_nosave(unsigned long pfn)
|
|
{
|
|
unsigned long begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
|
|
unsigned long end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
|
|
|
|
return (pfn >= begin_pfn) && (pfn < end_pfn);
|
|
}
|
|
|
|
void save_processor_state(void)
|
|
{
|
|
}
|
|
|
|
void restore_processor_state(void)
|
|
{
|
|
local_flush_tlb_all();
|
|
}
|