Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
[firefly-linux-kernel-4.4.55.git] / arch / arm64 / kernel / efi.c
index 4eeb17198cfaf598fd403b1e4040c77f5ee3068a..b6abc852f2a142123150662bc6dd6bf5c3de62af 100644 (file)
  *
  */
 
-#include <linux/atomic.h>
 #include <linux/dmi.h>
 #include <linux/efi.h>
-#include <linux/export.h>
-#include <linux/memblock.h>
-#include <linux/mm_types.h>
-#include <linux/bootmem.h>
-#include <linux/of.h>
-#include <linux/of_fdt.h>
-#include <linux/preempt.h>
-#include <linux/rbtree.h>
-#include <linux/rwsem.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
+#include <linux/init.h>
 
-#include <asm/cacheflush.h>
 #include <asm/efi.h>
-#include <asm/tlbflush.h>
-#include <asm/mmu_context.h>
-#include <asm/mmu.h>
-#include <asm/pgtable.h>
 
-struct efi_memory_map memmap;
-
-static u64 efi_system_table;
-
-static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss;
-
-static struct mm_struct efi_mm = {
-       .mm_rb                  = RB_ROOT,
-       .pgd                    = efi_pgd,
-       .mm_users               = ATOMIC_INIT(2),
-       .mm_count               = ATOMIC_INIT(1),
-       .mmap_sem               = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
-       .page_table_lock        = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
-       .mmlist                 = LIST_HEAD_INIT(efi_mm.mmlist),
-};
-
-static int __init is_normal_ram(efi_memory_desc_t *md)
-{
-       if (md->attribute & EFI_MEMORY_WB)
-               return 1;
-       return 0;
-}
-
-/*
- * Translate a EFI virtual address into a physical address: this is necessary,
- * as some data members of the EFI system table are virtually remapped after
- * SetVirtualAddressMap() has been called.
- */
-static phys_addr_t efi_to_phys(unsigned long addr)
+int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
 {
-       efi_memory_desc_t *md;
-
-       for_each_efi_memory_desc(&memmap, md) {
-               if (!(md->attribute & EFI_MEMORY_RUNTIME))
-                       continue;
-               if (md->virt_addr == 0)
-                       /* no virtual mapping has been installed by the stub */
-                       break;
-               if (md->virt_addr <= addr &&
-                   (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT))
-                       return md->phys_addr + addr - md->virt_addr;
-       }
-       return addr;
-}
-
-static int __init uefi_init(void)
-{
-       efi_char16_t *c16;
-       void *config_tables;
-       u64 table_size;
-       char vendor[100] = "unknown";
-       int i, retval;
-
-       efi.systab = early_memremap(efi_system_table,
-                                   sizeof(efi_system_table_t));
-       if (efi.systab == NULL) {
-               pr_warn("Unable to map EFI system table.\n");
-               return -ENOMEM;
-       }
-
-       set_bit(EFI_BOOT, &efi.flags);
-       set_bit(EFI_64BIT, &efi.flags);
+       pteval_t prot_val;
 
        /*
-        * Verify the EFI Table
+        * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
+        * executable, everything else can be mapped with the XN bits
+        * set.
         */
-       if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
-               pr_err("System table signature incorrect\n");
-               retval = -EINVAL;
-               goto out;
-       }
-       if ((efi.systab->hdr.revision >> 16) < 2)
-               pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n",
-                       efi.systab->hdr.revision >> 16,
-                       efi.systab->hdr.revision & 0xffff);
-
-       /* Show what we know for posterity */
-       c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor),
-                            sizeof(vendor) * sizeof(efi_char16_t));
-       if (c16) {
-               for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
-                       vendor[i] = c16[i];
-               vendor[i] = '\0';
-               early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t));
-       }
-
-       pr_info("EFI v%u.%.02u by %s\n",
-               efi.systab->hdr.revision >> 16,
-               efi.systab->hdr.revision & 0xffff, vendor);
-
-       table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
-       config_tables = early_memremap(efi_to_phys(efi.systab->tables),
-                                      table_size);
-       if (config_tables == NULL) {
-               pr_warn("Unable to map EFI config table array.\n");
-               retval = -ENOMEM;
-               goto out;
-       }
-       retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables,
-                                        sizeof(efi_config_table_64_t), NULL);
-
-       early_memunmap(config_tables, table_size);
-out:
-       early_memunmap(efi.systab,  sizeof(efi_system_table_t));
-       return retval;
-}
-
-/*
- * Return true for RAM regions we want to permanently reserve.
- */
-static __init int is_reserve_region(efi_memory_desc_t *md)
-{
-       switch (md->type) {
-       case EFI_LOADER_CODE:
-       case EFI_LOADER_DATA:
-       case EFI_BOOT_SERVICES_CODE:
-       case EFI_BOOT_SERVICES_DATA:
-       case EFI_CONVENTIONAL_MEMORY:
-       case EFI_PERSISTENT_MEMORY:
-               return 0;
-       default:
-               break;
-       }
-       return is_normal_ram(md);
-}
-
-static __init void reserve_regions(void)
-{
-       efi_memory_desc_t *md;
-       u64 paddr, npages, size;
-
-       if (efi_enabled(EFI_DBG))
-               pr_info("Processing EFI memory map:\n");
-
-       for_each_efi_memory_desc(&memmap, md) {
-               paddr = md->phys_addr;
-               npages = md->num_pages;
-
-               if (efi_enabled(EFI_DBG)) {
-                       char buf[64];
-
-                       pr_info("  0x%012llx-0x%012llx %s",
-                               paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
-                               efi_md_typeattr_format(buf, sizeof(buf), md));
-               }
-
-               memrange_efi_to_native(&paddr, &npages);
-               size = npages << PAGE_SHIFT;
-
-               if (is_normal_ram(md))
-                       early_init_dt_add_memory_arch(paddr, size);
-
-               if (is_reserve_region(md)) {
-                       memblock_reserve(paddr, size);
-                       if (efi_enabled(EFI_DBG))
-                               pr_cont("*");
-               }
-
-               if (efi_enabled(EFI_DBG))
-                       pr_cont("\n");
-       }
-
-       set_bit(EFI_MEMMAP, &efi.flags);
-}
-
-void __init efi_init(void)
-{
-       struct efi_fdt_params params;
-
-       /* Grab UEFI information placed in FDT by stub */
-       if (!efi_get_fdt_params(&params))
-               return;
-
-       efi_system_table = params.system_table;
-
-       memblock_reserve(params.mmap & PAGE_MASK,
-                        PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK)));
-       memmap.phys_map = params.mmap;
-       memmap.map = early_memremap(params.mmap, params.mmap_size);
-       if (memmap.map == NULL) {
-               /*
-               * If we are booting via UEFI, the UEFI memory map is the only
-               * description of memory we have, so there is little point in
-               * proceeding if we cannot access it.
-               */
-               panic("Unable to map EFI memory map.\n");
-       }
-       memmap.map_end = memmap.map + params.mmap_size;
-       memmap.desc_size = params.desc_size;
-       memmap.desc_version = params.desc_ver;
-
-       if (uefi_init() < 0)
-               return;
-
-       reserve_regions();
-       early_memunmap(memmap.map, params.mmap_size);
-}
-
-static bool __init efi_virtmap_init(void)
-{
-       efi_memory_desc_t *md;
-
-       init_new_context(NULL, &efi_mm);
-
-       for_each_efi_memory_desc(&memmap, md) {
-               pgprot_t prot;
-
-               if (!(md->attribute & EFI_MEMORY_RUNTIME))
-                       continue;
-               if (md->virt_addr == 0)
-                       return false;
-
-               pr_info("  EFI remap 0x%016llx => %p\n",
-                       md->phys_addr, (void *)md->virt_addr);
-
-               /*
-                * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
-                * executable, everything else can be mapped with the XN bits
-                * set.
-                */
-               if (!is_normal_ram(md))
-                       prot = __pgprot(PROT_DEVICE_nGnRE);
-               else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
-                        !PAGE_ALIGNED(md->phys_addr))
-                       prot = PAGE_KERNEL_EXEC;
-               else
-                       prot = PAGE_KERNEL;
-
-               create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr,
-                                  md->num_pages << EFI_PAGE_SHIFT, 
-                                  __pgprot(pgprot_val(prot) | PTE_NG));
-       }
-       return true;
-}
-
-/*
- * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
- * non-early mapping of the UEFI system table and virtual mappings for all
- * EFI_MEMORY_RUNTIME regions.
- */
-static int __init arm64_enable_runtime_services(void)
-{
-       u64 mapsize;
-
-       if (!efi_enabled(EFI_BOOT)) {
-               pr_info("EFI services will not be available.\n");
-               return 0;
-       }
-
-       if (efi_runtime_disabled()) {
-               pr_info("EFI runtime services will be disabled.\n");
-               return 0;
-       }
-
-       pr_info("Remapping and enabling EFI services.\n");
-
-       mapsize = memmap.map_end - memmap.map;
-       memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
-                                                  mapsize);
-       if (!memmap.map) {
-               pr_err("Failed to remap EFI memory map\n");
-               return -ENOMEM;
-       }
-       memmap.map_end = memmap.map + mapsize;
-       efi.memmap = &memmap;
-
-       efi.systab = (__force void *)ioremap_cache(efi_system_table,
-                                                  sizeof(efi_system_table_t));
-       if (!efi.systab) {
-               pr_err("Failed to remap EFI System Table\n");
-               return -ENOMEM;
-       }
-       set_bit(EFI_SYSTEM_TABLES, &efi.flags);
-
-       if (!efi_virtmap_init()) {
-               pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
-               return -ENOMEM;
-       }
-
-       /* Set up runtime services function pointers */
-       efi_native_runtime_setup();
-       set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
-
-       efi.runtime_version = efi.systab->hdr.revision;
-
+       if ((md->attribute & EFI_MEMORY_WB) == 0)
+               prot_val = PROT_DEVICE_nGnRE;
+       else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
+                !PAGE_ALIGNED(md->phys_addr))
+               prot_val = pgprot_val(PAGE_KERNEL_EXEC);
+       else
+               prot_val = pgprot_val(PAGE_KERNEL);
+
+       create_pgd_mapping(mm, md->phys_addr, md->virt_addr,
+                          md->num_pages << EFI_PAGE_SHIFT,
+                          __pgprot(prot_val | PTE_NG));
        return 0;
 }
-early_initcall(arm64_enable_runtime_services);
 
 static int __init arm64_dmi_init(void)
 {
@@ -337,23 +54,6 @@ static int __init arm64_dmi_init(void)
 }
 core_initcall(arm64_dmi_init);
 
-static void efi_set_pgd(struct mm_struct *mm)
-{
-       switch_mm(NULL, mm, NULL);
-}
-
-void efi_virtmap_load(void)
-{
-       preempt_disable();
-       efi_set_pgd(&efi_mm);
-}
-
-void efi_virtmap_unload(void)
-{
-       efi_set_pgd(current->active_mm);
-       preempt_enable();
-}
-
 /*
  * UpdateCapsule() depends on the system being shutdown via
  * ResetSystem().