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 41 int __init efi_alloc_page_tables(void) 42 { 43 return 0; 44 } 45 46 void efi_sync_low_kernel_mappings(void) {} 47 48 void __init efi_dump_pagetable(void) 49 { 50 #ifdef CONFIG_EFI_PGT_DUMP 51 ptdump_walk_pgd_level(NULL, swapper_pg_dir); 52 #endif 53 } 54 55 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) 56 { 57 return 0; 58 } 59 60 void __init efi_map_region(efi_memory_desc_t *md) 61 { 62 old_map_region(md); 63 } 64 65 void __init efi_map_region_fixed(efi_memory_desc_t *md) {} 66 void __init parse_efi_setup(u64 phys_addr, u32 data_len) {} 67 68 pgd_t * __init efi_call_phys_prolog(void) 69 { 70 struct desc_ptr gdt_descr; 71 pgd_t *save_pgd; 72 73 /* Current pgd is swapper_pg_dir, we'll restore it later: */ 74 save_pgd = swapper_pg_dir; 75 load_cr3(initial_page_table); 76 __flush_tlb_all(); 77 78 gdt_descr.address = get_cpu_gdt_paddr(0); 79 gdt_descr.size = GDT_SIZE - 1; 80 load_gdt(&gdt_descr); 81 82 return save_pgd; 83 } 84 85 void __init efi_call_phys_epilog(pgd_t *save_pgd) 86 { 87 struct desc_ptr gdt_descr; 88 89 gdt_descr.address = (unsigned long)get_cpu_gdt_rw(0); 90 gdt_descr.size = GDT_SIZE - 1; 91 load_gdt(&gdt_descr); 92 93 load_cr3(save_pgd); 94 __flush_tlb_all(); 95 } 96 97 void __init efi_runtime_update_mappings(void) 98 { 99 if (__supported_pte_mask & _PAGE_NX) 100 runtime_code_page_mkexec(); 101 } 102