[mirror_ubuntu-hirsute-kernel.git] / arch / arm64 / kernel / efi.c

/*
 * 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);
Commit	Line	Data
f84d0275 MS	1	/*
	2	* Extensible Firmware Interface
	3	*
	4	* Based on Extensible Firmware Interface Specification version 2.4
	5	*
	6	* Copyright (C) 2013, 2014 Linaro Ltd.
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*
	12	*/
	13
	14	#include <linux/efi.h>
	15	#include <linux/export.h>
	16	#include <linux/memblock.h>
	17	#include <linux/bootmem.h>
	18	#include <linux/of.h>
	19	#include <linux/of_fdt.h>
	20	#include <linux/sched.h>
	21	#include <linux/slab.h>
	22
	23	#include <asm/cacheflush.h>
	24	#include <asm/efi.h>
	25	#include <asm/tlbflush.h>
	26	#include <asm/mmu_context.h>
	27
	28	struct efi_memory_map memmap;
	29
	30	static efi_runtime_services_t *runtime;
	31
	32	static u64 efi_system_table;
	33
	34	static int uefi_debug __initdata;
	35	static int __init uefi_debug_setup(char *str)
	36	{
	37	uefi_debug = 1;
	38
	39	return 0;
	40	}
	41	early_param("uefi_debug", uefi_debug_setup);
	42
	43	static int __init is_normal_ram(efi_memory_desc_t *md)
	44	{
	45	if (md->attribute & EFI_MEMORY_WB)
	46	return 1;
	47	return 0;
	48	}
	49
	50	static void __init efi_setup_idmap(void)
	51	{
	52	struct memblock_region *r;
	53	efi_memory_desc_t *md;
	54	u64 paddr, npages, size;
	55
	56	for_each_memblock(memory, r)
	57	create_id_mapping(r->base, r->size, 0);
	58
	59	/* map runtime io spaces */
	60	for_each_efi_memory_desc(&memmap, md) {
	61	if (!(md->attribute & EFI_MEMORY_RUNTIME) \|\| is_normal_ram(md))
	62	continue;
	63	paddr = md->phys_addr;
	64	npages = md->num_pages;
65	memrange_efi_to_native(&paddr, &npages);
66	size = npages << PAGE_SHIFT;
67	create_id_mapping(paddr, size, 1);
68	}
69	}
70
71	static int __init uefi_init(void)
72	{
73	efi_char16_t *c16;
74	char vendor[100] = "unknown";
75	int i, retval;
76
77	efi.systab = early_memremap(efi_system_table,
78	sizeof(efi_system_table_t));
79	if (efi.systab == NULL) {
80	pr_warn("Unable to map EFI system table.\n");
81	return -ENOMEM;
82	}
83
84	set_bit(EFI_BOOT, &efi.flags);
85	set_bit(EFI_64BIT, &efi.flags);
86
87	/*
88	* Verify the EFI Table
89	*/
90	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
91	pr_err("System table signature incorrect\n");
92	return -EINVAL;
93	}
94	if ((efi.systab->hdr.revision >> 16) < 2)
95	pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n",
96	efi.systab->hdr.revision >> 16,
97	efi.systab->hdr.revision & 0xffff);
98
99	/* Show what we know for posterity */
100	c16 = early_memremap(efi.systab->fw_vendor,
101	sizeof(vendor));
102	if (c16) {
103	for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
104	vendor[i] = c16[i];
105	vendor[i] = '\0';
106	}
107
108	pr_info("EFI v%u.%.02u by %s\n",
109	efi.systab->hdr.revision >> 16,
110	efi.systab->hdr.revision & 0xffff, vendor);
111
112	retval = efi_config_init(NULL);
113	if (retval == 0)
114	set_bit(EFI_CONFIG_TABLES, &efi.flags);
115
116	early_memunmap(c16, sizeof(vendor));
117	early_memunmap(efi.systab, sizeof(efi_system_table_t));
118
119	return retval;
120	}
121
122	static __initdata char memory_type_name[][32] = {
123	{"Reserved"},
124	{"Loader Code"},
125	{"Loader Data"},
126	{"Boot Code"},
127	{"Boot Data"},
128	{"Runtime Code"},
129	{"Runtime Data"},
130	{"Conventional Memory"},
131	{"Unusable Memory"},
132	{"ACPI Reclaim Memory"},
133	{"ACPI Memory NVS"},
134	{"Memory Mapped I/O"},
135	{"MMIO Port Space"},
136	{"PAL Code"},
137	};
138
139	/*
140	* Return true for RAM regions we want to permanently reserve.
141	*/
142	static __init int is_reserve_region(efi_memory_desc_t *md)
143	{
144	if (!is_normal_ram(md))
145	return 0;
146
147	if (md->attribute & EFI_MEMORY_RUNTIME)
148	return 1;
149
150	if (md->type == EFI_ACPI_RECLAIM_MEMORY \|\|
151	md->type == EFI_RESERVED_TYPE)
152	return 1;
153
154	return 0;
155	}
156
157	static __init void reserve_regions(void)
158	{
159	efi_memory_desc_t *md;
160	u64 paddr, npages, size;
161
162	if (uefi_debug)
163	pr_info("Processing EFI memory map:\n");
164
165	for_each_efi_memory_desc(&memmap, md) {
166	paddr = md->phys_addr;
167	npages = md->num_pages;
168
169	if (uefi_debug)
170	pr_info(" 0x%012llx-0x%012llx [%s]",
171	paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
172	memory_type_name[md->type]);
173
174	memrange_efi_to_native(&paddr, &npages);
175	size = npages << PAGE_SHIFT;
176
177	if (is_normal_ram(md))
178	early_init_dt_add_memory_arch(paddr, size);
179
180	if (is_reserve_region(md) \|\|
181	md->type == EFI_BOOT_SERVICES_CODE \|\|
182	md->type == EFI_BOOT_SERVICES_DATA) {
183	memblock_reserve(paddr, size);
184	if (uefi_debug)
185	pr_cont("*");
186	}
187
188	if (uefi_debug)
189	pr_cont("\n");
190	}
191	}
192
193
194	static u64 __init free_one_region(u64 start, u64 end)
195	{
196	u64 size = end - start;
197
198	if (uefi_debug)
199	pr_info(" EFI freeing: 0x%012llx-0x%012llx\n", start, end - 1);
200
201	free_bootmem_late(start, size);
202	return size;
203	}
204
205	static u64 __init free_region(u64 start, u64 end)
206	{
207	u64 map_start, map_end, total = 0;
208
209	if (end <= start)
210	return total;
211
212	map_start = (u64)memmap.phys_map;
213	map_end = PAGE_ALIGN(map_start + (memmap.map_end - memmap.map));
214	map_start &= PAGE_MASK;
215
216	if (start < map_end && end > map_start) {
217	/* region overlaps UEFI memmap */
218	if (start < map_start)
219	total += free_one_region(start, map_start);
220
221	if (map_end < end)
222	total += free_one_region(map_end, end);
223	} else
224	total += free_one_region(start, end);
225
226	return total;
227	}
228
229	static void __init free_boot_services(void)
230	{
231	u64 total_freed = 0;
232	u64 keep_end, free_start, free_end;
233	efi_memory_desc_t *md;
234
235	/*
236	* If kernel uses larger pages than UEFI, we have to be careful
237	* not to inadvertantly free memory we want to keep if there is
238	* overlap at the kernel page size alignment. We do not want to
239	* free is_reserve_region() memory nor the UEFI memmap itself.
240	*
241	* The memory map is sorted, so we keep track of the end of
242	* any previous region we want to keep, remember any region
243	* we want to free and defer freeing it until we encounter
244	* the next region we want to keep. This way, before freeing
245	* it, we can clip it as needed to avoid freeing memory we
246	* want to keep for UEFI.
247	*/
248
249	keep_end = 0;
250	free_start = 0;
251
252	for_each_efi_memory_desc(&memmap, md) {
253	u64 paddr, npages, size;
254
255	if (is_reserve_region(md)) {
256	/*
257	* We don't want to free any memory from this region.
258	*/
259	if (free_start) {
260	/* adjust free_end then free region */
261	if (free_end > md->phys_addr)
262	free_end -= PAGE_SIZE;
263	total_freed += free_region(free_start, free_end);
264	free_start = 0;
265	}
266	keep_end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
267	continue;
268	}
269
270	if (md->type != EFI_BOOT_SERVICES_CODE &&
271	md->type != EFI_BOOT_SERVICES_DATA) {
272	/* no need to free this region */
273	continue;
274	}
275
276	/*
277	* We want to free memory from this region.
278	*/
279	paddr = md->phys_addr;
280	npages = md->num_pages;
281	memrange_efi_to_native(&paddr, &npages);
282	size = npages << PAGE_SHIFT;
283
284	if (free_start) {
285	if (paddr <= free_end)
286	free_end = paddr + size;
287	else {
288	total_freed += free_region(free_start, free_end);
289	free_start = paddr;
290	free_end = paddr + size;
291	}
292	} else {
293	free_start = paddr;
294	free_end = paddr + size;
295	}
296	if (free_start < keep_end) {
297	free_start += PAGE_SIZE;
298	if (free_start >= free_end)
299	free_start = 0;
300	}
301	}
302	if (free_start)
303	total_freed += free_region(free_start, free_end);
304
305	if (total_freed)
306	pr_info("Freed 0x%llx bytes of EFI boot services memory",
307	total_freed);
308	}
309
310	void __init efi_init(void)
311	{
312	struct efi_fdt_params params;
313
314	/* Grab UEFI information placed in FDT by stub */
315	if (!efi_get_fdt_params(&params, uefi_debug))
316	return;
317
318	efi_system_table = params.system_table;
319
320	memblock_reserve(params.mmap & PAGE_MASK,
321	PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK)));
322	memmap.phys_map = (void *)params.mmap;
323	memmap.map = early_memremap(params.mmap, params.mmap_size);
324	memmap.map_end = memmap.map + params.mmap_size;
325	memmap.desc_size = params.desc_size;
326	memmap.desc_version = params.desc_ver;
327
328	if (uefi_init() < 0)
329	return;
330
331	reserve_regions();
332	}
333
334	void __init efi_idmap_init(void)
335	{
336	/* boot time idmap_pg_dir is incomplete, so fill in missing parts */
337	efi_setup_idmap();
338	}
339
340	static int __init remap_region(efi_memory_desc_t md, void *new)
341	{
342	u64 paddr, vaddr, npages, size;
343
344	paddr = md->phys_addr;
345	npages = md->num_pages;
346	memrange_efi_to_native(&paddr, &npages);
347	size = npages << PAGE_SHIFT;
348
349	if (is_normal_ram(md))
350	vaddr = (__force u64)ioremap_cache(paddr, size);
351	else
352	vaddr = (__force u64)ioremap(paddr, size);
353
354	if (!vaddr) {
355	pr_err("Unable to remap 0x%llx pages @ %p\n",
356	npages, (void *)paddr);
357	return 0;
358	}
359
360	/* adjust for any rounding when EFI and system pagesize differs */
361	md->virt_addr = vaddr + (md->phys_addr - paddr);
362
363	if (uefi_debug)
364	pr_info(" EFI remap 0x%012llx => %p\n",
365	md->phys_addr, (void *)md->virt_addr);
366
367	memcpy(*new, md, memmap.desc_size);
368	*new += memmap.desc_size;
369
370	return 1;
371	}
372
373	/*
374	* Switch UEFI from an identity map to a kernel virtual map
375	*/
376	static int __init arm64_enter_virtual_mode(void)
377	{
378	efi_memory_desc_t *md;
379	phys_addr_t virtmap_phys;
380	void virtmap, virt_md;
381	efi_status_t status;
382	u64 mapsize;
383	int count = 0;
384	unsigned long flags;
385
386	if (!efi_enabled(EFI_BOOT)) {
387	pr_info("EFI services will not be available.\n");
388	return -1;
389	}
390
391	pr_info("Remapping and enabling EFI services.\n");
392
393	/* replace early memmap mapping with permanent mapping */
394	mapsize = memmap.map_end - memmap.map;
395	early_memunmap(memmap.map, mapsize);
396	memmap.map = (__force void *)ioremap_cache((phys_addr_t)memmap.phys_map,
397	mapsize);
398	memmap.map_end = memmap.map + mapsize;
399
400	efi.memmap = &memmap;
401
402	/* Map the runtime regions */
403	virtmap = kmalloc(mapsize, GFP_KERNEL);
404	if (!virtmap) {
405	pr_err("Failed to allocate EFI virtual memmap\n");
406	return -1;
407	}
408	virtmap_phys = virt_to_phys(virtmap);
409	virt_md = virtmap;
410
411	for_each_efi_memory_desc(&memmap, md) {
412	if (!(md->attribute & EFI_MEMORY_RUNTIME))
413	continue;
414	if (remap_region(md, &virt_md))
415	++count;
416	}
417
418	efi.systab = (__force void *)efi_lookup_mapped_addr(efi_system_table);
419	if (efi.systab)
420	set_bit(EFI_SYSTEM_TABLES, &efi.flags);
421
422	local_irq_save(flags);
423	cpu_switch_mm(idmap_pg_dir, &init_mm);
424
425	/* Call SetVirtualAddressMap with the physical address of the map */
426	runtime = efi.systab->runtime;
427	efi.set_virtual_address_map = runtime->set_virtual_address_map;
428
429	status = efi.set_virtual_address_map(count * memmap.desc_size,
430	memmap.desc_size,
431	memmap.desc_version,
432	(efi_memory_desc_t *)virtmap_phys);
433	cpu_set_reserved_ttbr0();
434	flush_tlb_all();
435	local_irq_restore(flags);
436
437	kfree(virtmap);
438
439	free_boot_services();
440
441	if (status != EFI_SUCCESS) {
442	pr_err("Failed to set EFI virtual address map! [%lx]\n",
443	status);
444	return -1;
445	}
446
447	/* Set up runtime services function pointers */
448	runtime = efi.systab->runtime;
449	efi.get_time = runtime->get_time;
450	efi.set_time = runtime->set_time;
451	efi.get_wakeup_time = runtime->get_wakeup_time;
452	efi.set_wakeup_time = runtime->set_wakeup_time;
453	efi.get_variable = runtime->get_variable;
454	efi.get_next_variable = runtime->get_next_variable;
455	efi.set_variable = runtime->set_variable;
456	efi.query_variable_info = runtime->query_variable_info;
457	efi.update_capsule = runtime->update_capsule;
458	efi.query_capsule_caps = runtime->query_capsule_caps;
459	efi.get_next_high_mono_count = runtime->get_next_high_mono_count;
460	efi.reset_system = runtime->reset_system;
461
462	set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
463
464	return 0;
465	}
466	early_initcall(arm64_enter_virtual_mode);