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 * prelog/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 efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) 45 { 46 return 0; 47 } 48 void efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages) {} 49 50 void __init efi_map_region(efi_memory_desc_t *md) 51 { 52 old_map_region(md); 53 } 54 55 void __init efi_map_region_fixed(efi_memory_desc_t *md) {} 56 void __init parse_efi_setup(u64 phys_addr, u32 data_len) {} 57 58 void efi_call_phys_prelog(void) 59 { 60 struct desc_ptr gdt_descr; 61 62 local_irq_save(efi_rt_eflags); 63 64 load_cr3(initial_page_table); 65 __flush_tlb_all(); 66 67 gdt_descr.address = __pa(get_cpu_gdt_table(0)); 68 gdt_descr.size = GDT_SIZE - 1; 69 load_gdt(&gdt_descr); 70 } 71 72 void efi_call_phys_epilog(void) 73 { 74 struct desc_ptr gdt_descr; 75 76 gdt_descr.address = (unsigned long)get_cpu_gdt_table(0); 77 gdt_descr.size = GDT_SIZE - 1; 78 load_gdt(&gdt_descr); 79 80 load_cr3(swapper_pg_dir); 81 __flush_tlb_all(); 82 83 local_irq_restore(efi_rt_eflags); 84 } 85 86 void __init efi_runtime_mkexec(void) 87 { 88 if (__supported_pte_mask & _PAGE_NX) 89 runtime_code_page_mkexec(); 90 } 91