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-rw-r--r--arch/unicore32/kernel/hibernate.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/unicore32/kernel/hibernate.c b/arch/unicore32/kernel/hibernate.c
new file mode 100644
index 000000000..9969ec374
--- /dev/null
+++ b/arch/unicore32/kernel/hibernate.c
@@ -0,0 +1,160 @@
+/*
+ * 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/sections.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();
+}