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authorMark Brown <broonie@kernel.org>2015-01-23 16:56:37 +0000
committerMark Brown <broonie@kernel.org>2015-01-23 16:56:37 +0000
commit250e8659c56d94320b877f659be45b8de130fa31 (patch)
tree71095fcd0b70a869ffc2589ec72bf2334b0643a6 /arch/arm64/kernel/efi.c
parent7adf3d9a27e4838d0af9250c53ad5744b84886ce (diff)
parentc7aae4d46ea5c7fb51edd68839588967ef2a7536 (diff)
downloadlinux-linaro-stable-250e8659c56d94320b877f659be45b8de130fa31.tar.gz
Merge remote-tracking branch 'lsk/v3.14/topic/arm64-efi' into linux-linaro-lsk-v3.14lsk-v3.14-15.01
Conflicts: arch/arm64/kernel/Makefile drivers/firmware/efi/efi-stub-helper.c
Diffstat (limited to 'arch/arm64/kernel/efi.c')
-rw-r--r--arch/arm64/kernel/efi.c469
1 files changed, 469 insertions, 0 deletions
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
new file mode 100644
index 000000000000..14db1f6e8d7f
--- /dev/null
+++ b/arch/arm64/kernel/efi.c
@@ -0,0 +1,469 @@
+/*
+ * Extensible Firmware Interface
+ *
+ * Based on Extensible Firmware Interface Specification version 2.4
+ *
+ * Copyright (C) 2013, 2014 Linaro Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/efi.h>
+#include <linux/export.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include <asm/cacheflush.h>
+#include <asm/efi.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+
+struct efi_memory_map memmap;
+
+static efi_runtime_services_t *runtime;
+
+static u64 efi_system_table;
+
+static int uefi_debug __initdata;
+static int __init uefi_debug_setup(char *str)
+{
+ uefi_debug = 1;
+
+ return 0;
+}
+early_param("uefi_debug", uefi_debug_setup);
+
+static int __init is_normal_ram(efi_memory_desc_t *md)
+{
+ if (md->attribute & EFI_MEMORY_WB)
+ return 1;
+ return 0;
+}
+
+static void __init efi_setup_idmap(void)
+{
+ struct memblock_region *r;
+ efi_memory_desc_t *md;
+ u64 paddr, npages, size;
+
+ for_each_memblock(memory, r)
+ create_id_mapping(r->base, r->size, 0);
+
+ /* map runtime io spaces */
+ for_each_efi_memory_desc(&memmap, md) {
+ if (!(md->attribute & EFI_MEMORY_RUNTIME) || is_normal_ram(md))
+ continue;
+ paddr = md->phys_addr;
+ npages = md->num_pages;
+ memrange_efi_to_native(&paddr, &npages);
+ size = npages << PAGE_SHIFT;
+ create_id_mapping(paddr, size, 1);
+ }
+}
+
+static int __init uefi_init(void)
+{
+ efi_char16_t *c16;
+ 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);
+
+ /*
+ * Verify the EFI Table
+ */
+ if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
+ pr_err("System table signature incorrect\n");
+ return -EINVAL;
+ }
+ 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.systab->fw_vendor,
+ sizeof(vendor));
+ if (c16) {
+ for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
+ vendor[i] = c16[i];
+ vendor[i] = '\0';
+ }
+
+ pr_info("EFI v%u.%.02u by %s\n",
+ efi.systab->hdr.revision >> 16,
+ efi.systab->hdr.revision & 0xffff, vendor);
+
+ retval = efi_config_init(NULL);
+ if (retval == 0)
+ set_bit(EFI_CONFIG_TABLES, &efi.flags);
+
+ early_memunmap(c16, sizeof(vendor));
+ early_memunmap(efi.systab, sizeof(efi_system_table_t));
+
+ return retval;
+}
+
+static __initdata char memory_type_name[][32] = {
+ {"Reserved"},
+ {"Loader Code"},
+ {"Loader Data"},
+ {"Boot Code"},
+ {"Boot Data"},
+ {"Runtime Code"},
+ {"Runtime Data"},
+ {"Conventional Memory"},
+ {"Unusable Memory"},
+ {"ACPI Reclaim Memory"},
+ {"ACPI Memory NVS"},
+ {"Memory Mapped I/O"},
+ {"MMIO Port Space"},
+ {"PAL Code"},
+};
+
+/*
+ * Return true for RAM regions we want to permanently reserve.
+ */
+static __init int is_reserve_region(efi_memory_desc_t *md)
+{
+ if (!is_normal_ram(md))
+ return 0;
+
+ if (md->attribute & EFI_MEMORY_RUNTIME)
+ return 1;
+
+ if (md->type == EFI_ACPI_RECLAIM_MEMORY ||
+ md->type == EFI_RESERVED_TYPE)
+ return 1;
+
+ return 0;
+}
+
+static __init void reserve_regions(void)
+{
+ efi_memory_desc_t *md;
+ u64 paddr, npages, size;
+
+ if (uefi_debug)
+ pr_info("Processing EFI memory map:\n");
+
+ for_each_efi_memory_desc(&memmap, md) {
+ paddr = md->phys_addr;
+ npages = md->num_pages;
+
+ if (uefi_debug)
+ pr_info(" 0x%012llx-0x%012llx [%s]",
+ paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
+ memory_type_name[md->type]);
+
+ 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) ||
+ md->type == EFI_BOOT_SERVICES_CODE ||
+ md->type == EFI_BOOT_SERVICES_DATA) {
+ memblock_reserve(paddr, size);
+ if (uefi_debug)
+ pr_cont("*");
+ }
+
+ if (uefi_debug)
+ pr_cont("\n");
+ }
+}
+
+
+static u64 __init free_one_region(u64 start, u64 end)
+{
+ u64 size = end - start;
+
+ if (uefi_debug)
+ pr_info(" EFI freeing: 0x%012llx-0x%012llx\n", start, end - 1);
+
+ free_bootmem_late(start, size);
+ return size;
+}
+
+static u64 __init free_region(u64 start, u64 end)
+{
+ u64 map_start, map_end, total = 0;
+
+ if (end <= start)
+ return total;
+
+ map_start = (u64)memmap.phys_map;
+ map_end = PAGE_ALIGN(map_start + (memmap.map_end - memmap.map));
+ map_start &= PAGE_MASK;
+
+ if (start < map_end && end > map_start) {
+ /* region overlaps UEFI memmap */
+ if (start < map_start)
+ total += free_one_region(start, map_start);
+
+ if (map_end < end)
+ total += free_one_region(map_end, end);
+ } else
+ total += free_one_region(start, end);
+
+ return total;
+}
+
+static void __init free_boot_services(void)
+{
+ u64 total_freed = 0;
+ u64 keep_end, free_start, free_end;
+ efi_memory_desc_t *md;
+
+ /*
+ * If kernel uses larger pages than UEFI, we have to be careful
+ * not to inadvertantly free memory we want to keep if there is
+ * overlap at the kernel page size alignment. We do not want to
+ * free is_reserve_region() memory nor the UEFI memmap itself.
+ *
+ * The memory map is sorted, so we keep track of the end of
+ * any previous region we want to keep, remember any region
+ * we want to free and defer freeing it until we encounter
+ * the next region we want to keep. This way, before freeing
+ * it, we can clip it as needed to avoid freeing memory we
+ * want to keep for UEFI.
+ */
+
+ keep_end = 0;
+ free_start = 0;
+
+ for_each_efi_memory_desc(&memmap, md) {
+ u64 paddr, npages, size;
+
+ if (is_reserve_region(md)) {
+ /*
+ * We don't want to free any memory from this region.
+ */
+ if (free_start) {
+ /* adjust free_end then free region */
+ if (free_end > md->phys_addr)
+ free_end -= PAGE_SIZE;
+ total_freed += free_region(free_start, free_end);
+ free_start = 0;
+ }
+ keep_end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
+ continue;
+ }
+
+ if (md->type != EFI_BOOT_SERVICES_CODE &&
+ md->type != EFI_BOOT_SERVICES_DATA) {
+ /* no need to free this region */
+ continue;
+ }
+
+ /*
+ * We want to free memory from this region.
+ */
+ paddr = md->phys_addr;
+ npages = md->num_pages;
+ memrange_efi_to_native(&paddr, &npages);
+ size = npages << PAGE_SHIFT;
+
+ if (free_start) {
+ if (paddr <= free_end)
+ free_end = paddr + size;
+ else {
+ total_freed += free_region(free_start, free_end);
+ free_start = paddr;
+ free_end = paddr + size;
+ }
+ } else {
+ free_start = paddr;
+ free_end = paddr + size;
+ }
+ if (free_start < keep_end) {
+ free_start += PAGE_SIZE;
+ if (free_start >= free_end)
+ free_start = 0;
+ }
+ }
+ if (free_start)
+ total_freed += free_region(free_start, free_end);
+
+ if (total_freed)
+ pr_info("Freed 0x%llx bytes of EFI boot services memory",
+ total_freed);
+}
+
+void __init efi_init(void)
+{
+ struct efi_fdt_params params;
+
+ /* Grab UEFI information placed in FDT by stub */
+ if (!efi_get_fdt_params(&params, uefi_debug))
+ 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 = (void *)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();
+}
+
+void __init efi_idmap_init(void)
+{
+ if (!efi_enabled(EFI_BOOT))
+ return;
+
+ /* boot time idmap_pg_dir is incomplete, so fill in missing parts */
+ efi_setup_idmap();
+}
+
+static int __init remap_region(efi_memory_desc_t *md, void **new)
+{
+ u64 paddr, vaddr, npages, size;
+
+ paddr = md->phys_addr;
+ npages = md->num_pages;
+ memrange_efi_to_native(&paddr, &npages);
+ size = npages << PAGE_SHIFT;
+
+ if (is_normal_ram(md))
+ vaddr = (__force u64)ioremap_cache(paddr, size);
+ else
+ vaddr = (__force u64)ioremap(paddr, size);
+
+ if (!vaddr) {
+ pr_err("Unable to remap 0x%llx pages @ %p\n",
+ npages, (void *)paddr);
+ return 0;
+ }
+
+ /* adjust for any rounding when EFI and system pagesize differs */
+ md->virt_addr = vaddr + (md->phys_addr - paddr);
+
+ if (uefi_debug)
+ pr_info(" EFI remap 0x%012llx => %p\n",
+ md->phys_addr, (void *)md->virt_addr);
+
+ memcpy(*new, md, memmap.desc_size);
+ *new += memmap.desc_size;
+
+ return 1;
+}
+
+/*
+ * Switch UEFI from an identity map to a kernel virtual map
+ */
+static int __init arm64_enter_virtual_mode(void)
+{
+ efi_memory_desc_t *md;
+ phys_addr_t virtmap_phys;
+ void *virtmap, *virt_md;
+ efi_status_t status;
+ u64 mapsize;
+ int count = 0;
+ unsigned long flags;
+
+ if (!efi_enabled(EFI_BOOT)) {
+ pr_info("EFI services will not be available.\n");
+ return -1;
+ }
+
+ pr_info("Remapping and enabling EFI services.\n");
+
+ /* replace early memmap mapping with permanent mapping */
+ mapsize = memmap.map_end - memmap.map;
+ early_memunmap(memmap.map, mapsize);
+ memmap.map = (__force void *)ioremap_cache((phys_addr_t)memmap.phys_map,
+ mapsize);
+ memmap.map_end = memmap.map + mapsize;
+
+ efi.memmap = &memmap;
+
+ /* Map the runtime regions */
+ virtmap = kmalloc(mapsize, GFP_KERNEL);
+ if (!virtmap) {
+ pr_err("Failed to allocate EFI virtual memmap\n");
+ return -1;
+ }
+ virtmap_phys = virt_to_phys(virtmap);
+ virt_md = virtmap;
+
+ for_each_efi_memory_desc(&memmap, md) {
+ if (!(md->attribute & EFI_MEMORY_RUNTIME))
+ continue;
+ if (remap_region(md, &virt_md))
+ ++count;
+ }
+
+ efi.systab = (__force void *)efi_lookup_mapped_addr(efi_system_table);
+ if (efi.systab)
+ set_bit(EFI_SYSTEM_TABLES, &efi.flags);
+
+ local_irq_save(flags);
+ cpu_switch_mm(idmap_pg_dir, &init_mm);
+
+ /* Call SetVirtualAddressMap with the physical address of the map */
+ runtime = efi.systab->runtime;
+ efi.set_virtual_address_map = runtime->set_virtual_address_map;
+
+ status = efi.set_virtual_address_map(count * memmap.desc_size,
+ memmap.desc_size,
+ memmap.desc_version,
+ (efi_memory_desc_t *)virtmap_phys);
+ cpu_set_reserved_ttbr0();
+ flush_tlb_all();
+ local_irq_restore(flags);
+
+ kfree(virtmap);
+
+ free_boot_services();
+
+ if (status != EFI_SUCCESS) {
+ pr_err("Failed to set EFI virtual address map! [%lx]\n",
+ status);
+ return -1;
+ }
+
+ /* Set up runtime services function pointers */
+ runtime = efi.systab->runtime;
+ efi.get_time = runtime->get_time;
+ efi.set_time = runtime->set_time;
+ efi.get_wakeup_time = runtime->get_wakeup_time;
+ efi.set_wakeup_time = runtime->set_wakeup_time;
+ efi.get_variable = runtime->get_variable;
+ efi.get_next_variable = runtime->get_next_variable;
+ efi.set_variable = runtime->set_variable;
+ efi.query_variable_info = runtime->query_variable_info;
+ efi.update_capsule = runtime->update_capsule;
+ efi.query_capsule_caps = runtime->query_capsule_caps;
+ efi.get_next_high_mono_count = runtime->get_next_high_mono_count;
+ efi.reset_system = runtime->reset_system;
+
+ set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+
+ return 0;
+}
+early_initcall(arm64_enter_virtual_mode);