efi: Add shared FDT related functions for ARM/ARM64

/*

 * FDT related Helper functions used by the EFI stub on multiple

 * architectures. This should be #included by the EFI stub

 * implementation files.

 *

 * Copyright 2013 Linaro Limited; author Roy Franz

 *

 * This file is part of the Linux kernel, and is made available

 * under the terms of the GNU General Public License version 2.

 *

 */

static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,

			       unsigned long orig_fdt_size,

			       void *fdt, int new_fdt_size, char *cmdline_ptr,

			       u64 initrd_addr, u64 initrd_size,

			       efi_memory_desc_t *memory_map,

			       unsigned long map_size, unsigned long desc_size,

			       u32 desc_ver)

{

	int node, prev;

	int status;

	u32 fdt_val32;

	u64 fdt_val64;

	/*

	 * Copy definition of linux_banner here.  Since this code is

	 * built as part of the decompressor for ARM v7, pulling

	 * in version.c where linux_banner is defined for the

	 * kernel brings other kernel dependencies with it.

	 */

	const char linux_banner[] =

	    "Linux version " UTS_RELEASE " (" LINUX_COMPILE_BY "@"

	    LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION "\n";

	/* Do some checks on provided FDT, if it exists*/

	if (orig_fdt) {

		if (fdt_check_header(orig_fdt)) {

			pr_efi_err(sys_table, "Device Tree header not valid!\n");

			return EFI_LOAD_ERROR;

		}

		/*

		 * We don't get the size of the FDT if we get if from a

		 * configuration table.

		 */

		if (orig_fdt_size && fdt_totalsize(orig_fdt) > orig_fdt_size) {

			pr_efi_err(sys_table, "Truncated device tree! foo!\n");

			return EFI_LOAD_ERROR;

		}

	}

	if (orig_fdt)

		status = fdt_open_into(orig_fdt, fdt, new_fdt_size);

	else

		status = fdt_create_empty_tree(fdt, new_fdt_size);

	if (status != 0)

		goto fdt_set_fail;

	/*

	 * Delete any memory nodes present. We must delete nodes which

	 * early_init_dt_scan_memory may try to use.

	 */

	prev = 0;

	for (;;) {

		const char *type, *name;

		int len;

		node = fdt_next_node(fdt, prev, NULL);

		if (node < 0)

			break;

		type = fdt_getprop(fdt, node, "device_type", &len);

		if (type && strncmp(type, "memory", len) == 0) {

			fdt_del_node(fdt, node);

			continue;

		}

		prev = node;

	}

	node = fdt_subnode_offset(fdt, 0, "chosen");

	if (node < 0) {

		node = fdt_add_subnode(fdt, 0, "chosen");

		if (node < 0) {

			status = node; /* node is error code when negative */

			goto fdt_set_fail;

		}

	}

	if ((cmdline_ptr != NULL) && (strlen(cmdline_ptr) > 0)) {

		status = fdt_setprop(fdt, node, "bootargs", cmdline_ptr,

				     strlen(cmdline_ptr) + 1);

		if (status)

			goto fdt_set_fail;

	}

	/* Set initrd address/end in device tree, if present */

	if (initrd_size != 0) {

		u64 initrd_image_end;

		u64 initrd_image_start = cpu_to_fdt64(initrd_addr);

		status = fdt_setprop(fdt, node, "linux,initrd-start",

				     &initrd_image_start, sizeof(u64));

		if (status)

			goto fdt_set_fail;

		initrd_image_end = cpu_to_fdt64(initrd_addr + initrd_size);

		status = fdt_setprop(fdt, node, "linux,initrd-end",

				     &initrd_image_end, sizeof(u64));

		if (status)

			goto fdt_set_fail;

	}

	/* Add FDT entries for EFI runtime services in chosen node. */

	node = fdt_subnode_offset(fdt, 0, "chosen");

	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)sys_table);

	status = fdt_setprop(fdt, node, "linux,uefi-system-table",

			     &fdt_val64, sizeof(fdt_val64));

	if (status)

		goto fdt_set_fail;

	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)memory_map);

	status = fdt_setprop(fdt, node, "linux,uefi-mmap-start",

			     &fdt_val64,  sizeof(fdt_val64));

	if (status)

		goto fdt_set_fail;

	fdt_val32 = cpu_to_fdt32(map_size);

	status = fdt_setprop(fdt, node, "linux,uefi-mmap-size",

			     &fdt_val32,  sizeof(fdt_val32));

	if (status)

		goto fdt_set_fail;

	fdt_val32 = cpu_to_fdt32(desc_size);

	status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-size",

			     &fdt_val32, sizeof(fdt_val32));

	if (status)

		goto fdt_set_fail;

	fdt_val32 = cpu_to_fdt32(desc_ver);

	status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-ver",

			     &fdt_val32, sizeof(fdt_val32));

	if (status)

		goto fdt_set_fail;

	/*

	 * Add kernel version banner so stub/kernel match can be

	 * verified.

	 */

	status = fdt_setprop_string(fdt, node, "linux,uefi-stub-kern-ver",

			     linux_banner);

	if (status)

		goto fdt_set_fail;

	return EFI_SUCCESS;

fdt_set_fail:

	if (status == -FDT_ERR_NOSPACE)

		return EFI_BUFFER_TOO_SMALL;

	return EFI_LOAD_ERROR;

}

#ifndef EFI_FDT_ALIGN

#define EFI_FDT_ALIGN EFI_PAGE_SIZE

#endif

/*

 * Allocate memory for a new FDT, then add EFI, commandline, and

 * initrd related fields to the FDT.  This routine increases the

 * FDT allocation size until the allocated memory is large

 * enough.  EFI allocations are in EFI_PAGE_SIZE granules,

 * which are fixed at 4K bytes, so in most cases the first

 * allocation should succeed.

 * EFI boot services are exited at the end of this function.

 * There must be no allocations between the get_memory_map()

 * call and the exit_boot_services() call, so the exiting of

 * boot services is very tightly tied to the creation of the FDT

 * with the final memory map in it.

 */

efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,

					    void *handle,

					    unsigned long *new_fdt_addr,

					    unsigned long max_addr,

					    u64 initrd_addr, u64 initrd_size,

					    char *cmdline_ptr,

					    unsigned long fdt_addr,

					    unsigned long fdt_size)

{

	unsigned long map_size, desc_size;

	u32 desc_ver;

	unsigned long mmap_key;

	efi_memory_desc_t *memory_map;

	unsigned long new_fdt_size;

	efi_status_t status;

	/*

	 * Estimate size of new FDT, and allocate memory for it. We

	 * will allocate a bigger buffer if this ends up being too

	 * small, so a rough guess is OK here.

	 */

	new_fdt_size = fdt_size + EFI_PAGE_SIZE;

	while (1) {

		status = efi_high_alloc(sys_table, new_fdt_size, EFI_FDT_ALIGN,

					new_fdt_addr, max_addr);

		if (status != EFI_SUCCESS) {

			pr_efi_err(sys_table, "Unable to allocate memory for new device tree.\n");

			goto fail;

		}

		/*

		 * Now that we have done our final memory allocation (and free)

		 * we can get the memory map key  needed for

		 * exit_boot_services().

		 */

		status = efi_get_memory_map(sys_table, &memory_map, &map_size,

					    &desc_size, &desc_ver, &mmap_key);

		if (status != EFI_SUCCESS)

			goto fail_free_new_fdt;

		status = update_fdt(sys_table,

				    (void *)fdt_addr, fdt_size,

				    (void *)*new_fdt_addr, new_fdt_size,

				    cmdline_ptr, initrd_addr, initrd_size,

				    memory_map, map_size, desc_size, desc_ver);

		/* Succeeding the first time is the expected case. */

		if (status == EFI_SUCCESS)

			break;

		if (status == EFI_BUFFER_TOO_SMALL) {

			/*

			 * We need to allocate more space for the new

			 * device tree, so free existing buffer that is

			 * too small.  Also free memory map, as we will need

			 * to get new one that reflects the free/alloc we do

			 * on the device tree buffer.

			 */

			efi_free(sys_table, new_fdt_size, *new_fdt_addr);

			sys_table->boottime->free_pool(memory_map);

			new_fdt_size += EFI_PAGE_SIZE;

		} else {

			pr_efi_err(sys_table, "Unable to constuct new device tree.\n");

			goto fail_free_mmap;

		}

	}

	/* Now we are ready to exit_boot_services.*/

	status = sys_table->boottime->exit_boot_services(handle, mmap_key);

	if (status == EFI_SUCCESS)

		return status;

	pr_efi_err(sys_table, "Exit boot services failed.\n");

fail_free_mmap:

	sys_table->boottime->free_pool(memory_map);

fail_free_new_fdt:

	efi_free(sys_table, new_fdt_size, *new_fdt_addr);

fail:

	return EFI_LOAD_ERROR;

}

static void *get_fdt(efi_system_table_t *sys_table)

{

	efi_guid_t fdt_guid = DEVICE_TREE_GUID;

	efi_config_table_t *tables;

	void *fdt;

	int i;

	tables = (efi_config_table_t *) sys_table->tables;

	fdt = NULL;

	for (i = 0; i < sys_table->nr_tables; i++)

		if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {

			fdt = (void *) tables[i].table;

			break;

	 }

	return fdt;

}

#define EFI_FILE_SYSTEM_GUID \

    EFI_GUID(  0x964e5b22, 0x6459, 0x11d2, 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )

#define DEVICE_TREE_GUID \

    EFI_GUID(  0xb1b621d5, 0xf19c, 0x41a5, 0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0 )

typedef struct {

	efi_guid_t guid;

	u64 table;