diff options
Diffstat (limited to 'arch/arm64/kernel/efi.c')
-rw-r--r-- | arch/arm64/kernel/efi.c | 329 |
1 files changed, 16 insertions, 313 deletions
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index de46b50..b6abc85 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -11,307 +11,34 @@ * */ -#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); - - 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(¶ms)) - 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); - 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; - - for_each_efi_memory_desc(&memmap, md) { - u64 paddr, npages, size; - pgprot_t prot; - - if (!(md->attribute & EFI_MEMORY_RUNTIME)) - continue; - if (md->virt_addr == 0) - return false; - - paddr = md->phys_addr; - npages = md->num_pages; - memrange_efi_to_native(&paddr, &npages); - size = npages << PAGE_SHIFT; - - 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, paddr, md->virt_addr, size, prot); - } - 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 -1; - } - - if (efi_runtime_disabled()) { - pr_info("EFI runtime services will be disabled.\n"); - return -1; - } - - 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 -1; - } - 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 -1; - } - 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 -1; - } - - /* 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) { @@ -327,30 +54,6 @@ static int __init arm64_dmi_init(void) } core_initcall(arm64_dmi_init); -static void efi_set_pgd(struct mm_struct *mm) -{ - if (mm == &init_mm) - cpu_set_reserved_ttbr0(); - else - cpu_switch_mm(mm->pgd, mm); - - local_flush_tlb_all(); - if (icache_is_aivivt()) - __local_flush_icache_all(); -} - -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(). |