1/*
2 * Extensible Firmware Interface
3 *
4 * Based on Extensible Firmware Interface Specification version 1.0
5 *
6 * Copyright (C) 1999 VA Linux Systems
7 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
8 * Copyright (C) 1999-2002 Hewlett-Packard Co.
9 *	David Mosberger-Tang <davidm@hpl.hp.com>
10 *	Stephane Eranian <eranian@hpl.hp.com>
11 *
12 * All EFI Runtime Services are not implemented yet as EFI only
13 * supports physical mode addressing on SoftSDV. This is to be fixed
14 * in a future version.  --drummond 1999-07-20
15 *
16 * Implemented EFI runtime services and virtual mode calls.  --davidm
17 *
18 * Goutham Rao: <goutham.rao@intel.com>
19 *	Skip non-WB memory and ignore empty memory ranges.
20 */
21
22#include <linux/kernel.h>
23#include <linux/types.h>
24#include <linux/ioport.h>
25#include <linux/efi.h>
26
27#include <asm/io.h>
28#include <asm/desc.h>
29#include <asm/page.h>
30#include <asm/pgtable.h>
31#include <asm/tlbflush.h>
32#include <asm/efi.h>
33
34/*
35 * To make EFI call EFI runtime service in physical addressing mode we need
36 * prolog/epilog before/after the invocation to claim the EFI runtime service
37 * handler exclusively and to duplicate a memory mapping in low memory space,
38 * say 0 - 3G.
39 */
40
41void efi_sync_low_kernel_mappings(void) {}
42void __init efi_dump_pagetable(void) {}
43int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
44{
45	return 0;
46}
47void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages)
48{
49}
50
51void __init efi_map_region(efi_memory_desc_t *md)
52{
53	old_map_region(md);
54}
55
56void __init efi_map_region_fixed(efi_memory_desc_t *md) {}
57void __init parse_efi_setup(u64 phys_addr, u32 data_len) {}
58
59pgd_t * __init efi_call_phys_prolog(void)
60{
61	struct desc_ptr gdt_descr;
62	pgd_t *save_pgd;
63
64	/* Current pgd is swapper_pg_dir, we'll restore it later: */
65	save_pgd = swapper_pg_dir;
66	load_cr3(initial_page_table);
67	__flush_tlb_all();
68
69	gdt_descr.address = __pa(get_cpu_gdt_table(0));
70	gdt_descr.size = GDT_SIZE - 1;
71	load_gdt(&gdt_descr);
72
73	return save_pgd;
74}
75
76void __init efi_call_phys_epilog(pgd_t *save_pgd)
77{
78	struct desc_ptr gdt_descr;
79
80	gdt_descr.address = (unsigned long)get_cpu_gdt_table(0);
81	gdt_descr.size = GDT_SIZE - 1;
82	load_gdt(&gdt_descr);
83
84	load_cr3(save_pgd);
85	__flush_tlb_all();
86}
87
88void __init efi_runtime_mkexec(void)
89{
90	if (__supported_pte_mask & _PAGE_NX)
91		runtime_code_page_mkexec();
92}
93