| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Extensible Firmware Interface |
| * |
| * Based on Extensible Firmware Interface Specification version 1.0 |
| * |
| * Copyright (C) 1999 VA Linux Systems |
| * Copyright (C) 1999 Walt Drummond <drummond@valinux.com> |
| * Copyright (C) 1999-2002 Hewlett-Packard Co. |
| * David Mosberger-Tang <davidm@hpl.hp.com> |
| * Stephane Eranian <eranian@hpl.hp.com> |
| * |
| * All EFI Runtime Services are not implemented yet as EFI only |
| * supports physical mode addressing on SoftSDV. This is to be fixed |
| * in a future version. --drummond 1999-07-20 |
| * |
| * Implemented EFI runtime services and virtual mode calls. --davidm |
| * |
| * Goutham Rao: <goutham.rao@intel.com> |
| * Skip non-WB memory and ignore empty memory ranges. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/ioport.h> |
| #include <linux/efi.h> |
| |
| #include <asm/io.h> |
| #include <asm/desc.h> |
| #include <asm/page.h> |
| #include <asm/pgtable.h> |
| #include <asm/tlbflush.h> |
| #include <asm/efi.h> |
| |
| /* |
| * To make EFI call EFI runtime service in physical addressing mode we need |
| * prolog/epilog before/after the invocation to claim the EFI runtime service |
| * handler exclusively and to duplicate a memory mapping in low memory space, |
| * say 0 - 3G. |
| */ |
| |
| int __init efi_alloc_page_tables(void) |
| { |
| return 0; |
| } |
| |
| void efi_sync_low_kernel_mappings(void) {} |
| |
| void __init efi_dump_pagetable(void) |
| { |
| #ifdef CONFIG_EFI_PGT_DUMP |
| ptdump_walk_pgd_level(NULL, swapper_pg_dir); |
| #endif |
| } |
| |
| int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) |
| { |
| return 0; |
| } |
| |
| void __init efi_map_region(efi_memory_desc_t *md) |
| { |
| old_map_region(md); |
| } |
| |
| void __init efi_map_region_fixed(efi_memory_desc_t *md) {} |
| void __init parse_efi_setup(u64 phys_addr, u32 data_len) {} |
| |
| pgd_t * __init efi_call_phys_prolog(void) |
| { |
| struct desc_ptr gdt_descr; |
| pgd_t *save_pgd; |
| |
| /* Current pgd is swapper_pg_dir, we'll restore it later: */ |
| save_pgd = swapper_pg_dir; |
| load_cr3(initial_page_table); |
| __flush_tlb_all(); |
| |
| gdt_descr.address = get_cpu_gdt_paddr(0); |
| gdt_descr.size = GDT_SIZE - 1; |
| load_gdt(&gdt_descr); |
| |
| return save_pgd; |
| } |
| |
| void __init efi_call_phys_epilog(pgd_t *save_pgd) |
| { |
| load_cr3(save_pgd); |
| __flush_tlb_all(); |
| |
| load_fixmap_gdt(0); |
| } |
| |
| void __init efi_runtime_update_mappings(void) |
| { |
| if (__supported_pte_mask & _PAGE_NX) |
| runtime_code_page_mkexec(); |
| } |