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 disable interrupt, to 37 * claim EFI runtime service handler exclusively and to duplicate a memory in 38 * low memory space say 0 - 3G. 39 */ 40 static unsigned long efi_rt_eflags; 41 42 void efi_sync_low_kernel_mappings(void) {} 43 void __init efi_dump_pagetable(void) {} 44 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) 45 { 46 return 0; 47 } 48 void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages) 49 { 50 } 51 52 void __init efi_map_region(efi_memory_desc_t *md) 53 { 54 old_map_region(md); 55 } 56 57 void __init efi_map_region_fixed(efi_memory_desc_t *md) {} 58 void __init parse_efi_setup(u64 phys_addr, u32 data_len) {} 59 60 void __init efi_call_phys_prolog(void) 61 { 62 struct desc_ptr gdt_descr; 63 64 local_irq_save(efi_rt_eflags); 65 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 74 void __init efi_call_phys_epilog(void) 75 { 76 struct desc_ptr gdt_descr; 77 78 gdt_descr.address = (unsigned long)get_cpu_gdt_table(0); 79 gdt_descr.size = GDT_SIZE - 1; 80 load_gdt(&gdt_descr); 81 82 load_cr3(swapper_pg_dir); 83 __flush_tlb_all(); 84 85 local_irq_restore(efi_rt_eflags); 86 } 87 88 void __init efi_runtime_mkexec(void) 89 { 90 if (__supported_pte_mask & _PAGE_NX) 91 runtime_code_page_mkexec(); 92 } 93