arm64: add EFI runtime services (f84d0275) · Commits · 戴 / test

arch/arm64/Kconfig

+15 −0

Original line number	Diff line number	Diff line
		@@ -280,6 +280,19 @@ config CMDLINE_FORCE
		This is useful if you cannot or don't want to change the
		command-line options your boot loader passes to the kernel.

		config EFI
		bool "UEFI runtime support"
		depends on OF && !CPU_BIG_ENDIAN
		select LIBFDT
		select UCS2_STRING
		select EFI_PARAMS_FROM_FDT
		default y
		help
		This option provides support for runtime services provided
		by UEFI firmware (such as non-volatile variables, realtime
		clock, and platform reset). This is only useful on systems
		that have UEFI firmware.

		endmenu

		menu "Userspace binary formats"
		@@ -333,6 +346,8 @@ source "net/Kconfig"

		source "drivers/Kconfig"

		source "drivers/firmware/Kconfig"

		source "fs/Kconfig"

		source "arch/arm64/kvm/Kconfig"

arch/arm64/include/asm/efi.h

0 → 100644

+14 −0

Original line number	Diff line number	Diff line
		#ifndef _ASM_EFI_H
		#define _ASM_EFI_H

		#include <asm/io.h>

		#ifdef CONFIG_EFI
		extern void efi_init(void);
		extern void efi_idmap_init(void);
		#else
		#define efi_init()
		#define efi_idmap_init()
		#endif

		#endif /* _ASM_EFI_H */

arch/arm64/kernel/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@ arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
		arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o
		arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o
		arm64-obj-$(CONFIG_KGDB) += kgdb.o
		arm64-obj-$(CONFIG_EFI) += efi.o

		obj-y += $(arm64-obj-y) vdso/
		obj-m += $(arm64-obj-m)

arch/arm64/kernel/efi.c

0 → 100644

+466 −0

Original line number	Diff line number	Diff line
		/*
		* 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)
		{
		/* 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);

arch/arm64/kernel/setup.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@
		#include <linux/memblock.h>
		#include <linux/of_fdt.h>
		#include <linux/of_platform.h>
		#include <linux/efi.h>

		#include <asm/fixmap.h>
		#include <asm/cputype.h>
		@@ -55,6 +56,7 @@
		#include <asm/traps.h>
		#include <asm/memblock.h>
		#include <asm/psci.h>
		#include <asm/efi.h>

		unsigned int processor_id;
		EXPORT_SYMBOL(processor_id);
		@@ -366,11 +368,14 @@ void __init setup_arch(char **cmdline_p)

		parse_early_param();

		efi_init();
		arm64_memblock_init();

		paging_init();
		request_standard_resources();

		efi_idmap_init();

		unflatten_device_tree();

		psci_init();

Admin message