summaryrefslogtreecommitdiff
path: root/drivers/firmware/efi/efi-stub-helper.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/firmware/efi/efi-stub-helper.c')
-rw-r--r--drivers/firmware/efi/efi-stub-helper.c636
1 files changed, 636 insertions, 0 deletions
diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c
new file mode 100644
index 000000000000..b6bffbfd3be7
--- /dev/null
+++ b/drivers/firmware/efi/efi-stub-helper.c
@@ -0,0 +1,636 @@
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ *
+ * This file is part of the Linux kernel, and is made available
+ * under the terms of the GNU General Public License version 2.
+ *
+ */
+#define EFI_READ_CHUNK_SIZE (1024 * 1024)
+
+struct file_info {
+ efi_file_handle_t *handle;
+ u64 size;
+};
+
+
+
+
+static void efi_char16_printk(efi_system_table_t *sys_table_arg,
+ efi_char16_t *str)
+{
+ struct efi_simple_text_output_protocol *out;
+
+ out = (struct efi_simple_text_output_protocol *)sys_table_arg->con_out;
+ efi_call_phys2(out->output_string, out, str);
+}
+
+static void efi_printk(efi_system_table_t *sys_table_arg, char *str)
+{
+ char *s8;
+
+ for (s8 = str; *s8; s8++) {
+ efi_char16_t ch[2] = { 0 };
+
+ ch[0] = *s8;
+ if (*s8 == '\n') {
+ efi_char16_t nl[2] = { '\r', 0 };
+ efi_char16_printk(sys_table_arg, nl);
+ }
+
+ efi_char16_printk(sys_table_arg, ch);
+ }
+}
+
+
+static efi_status_t efi_get_memory_map(efi_system_table_t *sys_table_arg,
+ efi_memory_desc_t **map,
+ unsigned long *map_size,
+ unsigned long *desc_size,
+ u32 *desc_ver,
+ unsigned long *key_ptr)
+{
+ efi_memory_desc_t *m = NULL;
+ efi_status_t status;
+ unsigned long key;
+ u32 desc_version;
+
+ *map_size = sizeof(*m) * 32;
+again:
+ /*
+ * Add an additional efi_memory_desc_t because we're doing an
+ * allocation which may be in a new descriptor region.
+ */
+ *map_size += sizeof(*m);
+ status = efi_call_phys3(sys_table_arg->boottime->allocate_pool,
+ EFI_LOADER_DATA, *map_size, (void **)&m);
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ status = efi_call_phys5(sys_table_arg->boottime->get_memory_map,
+ map_size, m, &key, desc_size, &desc_version);
+ if (status == EFI_BUFFER_TOO_SMALL) {
+ efi_call_phys1(sys_table_arg->boottime->free_pool, m);
+ goto again;
+ }
+
+ if (status != EFI_SUCCESS)
+ efi_call_phys1(sys_table_arg->boottime->free_pool, m);
+ if (key_ptr && status == EFI_SUCCESS)
+ *key_ptr = key;
+ if (desc_ver && status == EFI_SUCCESS)
+ *desc_ver = desc_version;
+
+fail:
+ *map = m;
+ return status;
+}
+
+/*
+ * Allocate at the highest possible address that is not above 'max'.
+ */
+static efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
+ unsigned long size, unsigned long align,
+ unsigned long *addr, unsigned long max)
+{
+ unsigned long map_size, desc_size;
+ efi_memory_desc_t *map;
+ efi_status_t status;
+ unsigned long nr_pages;
+ u64 max_addr = 0;
+ int i;
+
+ status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
+ NULL, NULL);
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ /*
+ * Enforce minimum alignment that EFI requires when requesting
+ * a specific address. We are doing page-based allocations,
+ * so we must be aligned to a page.
+ */
+ if (align < EFI_PAGE_SIZE)
+ align = EFI_PAGE_SIZE;
+
+ nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+again:
+ for (i = 0; i < map_size / desc_size; i++) {
+ efi_memory_desc_t *desc;
+ unsigned long m = (unsigned long)map;
+ u64 start, end;
+
+ desc = (efi_memory_desc_t *)(m + (i * desc_size));
+ if (desc->type != EFI_CONVENTIONAL_MEMORY)
+ continue;
+
+ if (desc->num_pages < nr_pages)
+ continue;
+
+ start = desc->phys_addr;
+ end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+
+ if ((start + size) > end || (start + size) > max)
+ continue;
+
+ if (end - size > max)
+ end = max;
+
+ if (round_down(end - size, align) < start)
+ continue;
+
+ start = round_down(end - size, align);
+
+ /*
+ * Don't allocate at 0x0. It will confuse code that
+ * checks pointers against NULL.
+ */
+ if (start == 0x0)
+ continue;
+
+ if (start > max_addr)
+ max_addr = start;
+ }
+
+ if (!max_addr)
+ status = EFI_NOT_FOUND;
+ else {
+ status = efi_call_phys4(sys_table_arg->boottime->allocate_pages,
+ EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+ nr_pages, &max_addr);
+ if (status != EFI_SUCCESS) {
+ max = max_addr;
+ max_addr = 0;
+ goto again;
+ }
+
+ *addr = max_addr;
+ }
+
+ efi_call_phys1(sys_table_arg->boottime->free_pool, map);
+
+fail:
+ return status;
+}
+
+/*
+ * Allocate at the lowest possible address.
+ */
+static efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
+ unsigned long size, unsigned long align,
+ unsigned long *addr)
+{
+ unsigned long map_size, desc_size;
+ efi_memory_desc_t *map;
+ efi_status_t status;
+ unsigned long nr_pages;
+ int i;
+
+ status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
+ NULL, NULL);
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ /*
+ * Enforce minimum alignment that EFI requires when requesting
+ * a specific address. We are doing page-based allocations,
+ * so we must be aligned to a page.
+ */
+ if (align < EFI_PAGE_SIZE)
+ align = EFI_PAGE_SIZE;
+
+ nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+ for (i = 0; i < map_size / desc_size; i++) {
+ efi_memory_desc_t *desc;
+ unsigned long m = (unsigned long)map;
+ u64 start, end;
+
+ desc = (efi_memory_desc_t *)(m + (i * desc_size));
+
+ if (desc->type != EFI_CONVENTIONAL_MEMORY)
+ continue;
+
+ if (desc->num_pages < nr_pages)
+ continue;
+
+ start = desc->phys_addr;
+ end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+
+ /*
+ * Don't allocate at 0x0. It will confuse code that
+ * checks pointers against NULL. Skip the first 8
+ * bytes so we start at a nice even number.
+ */
+ if (start == 0x0)
+ start += 8;
+
+ start = round_up(start, align);
+ if ((start + size) > end)
+ continue;
+
+ status = efi_call_phys4(sys_table_arg->boottime->allocate_pages,
+ EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+ nr_pages, &start);
+ if (status == EFI_SUCCESS) {
+ *addr = start;
+ break;
+ }
+ }
+
+ if (i == map_size / desc_size)
+ status = EFI_NOT_FOUND;
+
+ efi_call_phys1(sys_table_arg->boottime->free_pool, map);
+fail:
+ return status;
+}
+
+static void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
+ unsigned long addr)
+{
+ unsigned long nr_pages;
+
+ if (!size)
+ return;
+
+ nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+ efi_call_phys2(sys_table_arg->boottime->free_pages, addr, nr_pages);
+}
+
+
+/*
+ * Check the cmdline for a LILO-style file= arguments.
+ *
+ * We only support loading a file from the same filesystem as
+ * the kernel image.
+ */
+static efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg,
+ efi_loaded_image_t *image,
+ char *cmd_line, char *option_string,
+ unsigned long max_addr,
+ unsigned long *load_addr,
+ unsigned long *load_size)
+{
+ struct file_info *files;
+ unsigned long file_addr;
+ efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+ u64 file_size_total;
+ efi_file_io_interface_t *io;
+ efi_file_handle_t *fh;
+ efi_status_t status;
+ int nr_files;
+ char *str;
+ int i, j, k;
+
+ file_addr = 0;
+ file_size_total = 0;
+
+ str = cmd_line;
+
+ j = 0; /* See close_handles */
+
+ if (!load_addr || !load_size)
+ return EFI_INVALID_PARAMETER;
+
+ *load_addr = 0;
+ *load_size = 0;
+
+ if (!str || !*str)
+ return EFI_SUCCESS;
+
+ for (nr_files = 0; *str; nr_files++) {
+ str = strstr(str, option_string);
+ if (!str)
+ break;
+
+ str += strlen(option_string);
+
+ /* Skip any leading slashes */
+ while (*str == '/' || *str == '\\')
+ str++;
+
+ while (*str && *str != ' ' && *str != '\n')
+ str++;
+ }
+
+ if (!nr_files)
+ return EFI_SUCCESS;
+
+ status = efi_call_phys3(sys_table_arg->boottime->allocate_pool,
+ EFI_LOADER_DATA,
+ nr_files * sizeof(*files),
+ (void **)&files);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to alloc mem for file handle list\n");
+ goto fail;
+ }
+
+ str = cmd_line;
+ for (i = 0; i < nr_files; i++) {
+ struct file_info *file;
+ efi_file_handle_t *h;
+ efi_file_info_t *info;
+ efi_char16_t filename_16[256];
+ unsigned long info_sz;
+ efi_guid_t info_guid = EFI_FILE_INFO_ID;
+ efi_char16_t *p;
+ u64 file_sz;
+
+ str = strstr(str, option_string);
+ if (!str)
+ break;
+
+ str += strlen(option_string);
+
+ file = &files[i];
+ p = filename_16;
+
+ /* Skip any leading slashes */
+ while (*str == '/' || *str == '\\')
+ str++;
+
+ while (*str && *str != ' ' && *str != '\n') {
+ if ((u8 *)p >= (u8 *)filename_16 + sizeof(filename_16))
+ break;
+
+ if (*str == '/') {
+ *p++ = '\\';
+ str++;
+ } else {
+ *p++ = *str++;
+ }
+ }
+
+ *p = '\0';
+
+ /* Only open the volume once. */
+ if (!i) {
+ efi_boot_services_t *boottime;
+
+ boottime = sys_table_arg->boottime;
+
+ status = efi_call_phys3(boottime->handle_protocol,
+ image->device_handle, &fs_proto,
+ (void **)&io);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to handle fs_proto\n");
+ goto free_files;
+ }
+
+ status = efi_call_phys2(io->open_volume, io, &fh);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to open volume\n");
+ goto free_files;
+ }
+ }
+
+ status = efi_call_phys5(fh->open, fh, &h, filename_16,
+ EFI_FILE_MODE_READ, (u64)0);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to open file: ");
+ efi_char16_printk(sys_table_arg, filename_16);
+ efi_printk(sys_table_arg, "\n");
+ goto close_handles;
+ }
+
+ file->handle = h;
+
+ info_sz = 0;
+ status = efi_call_phys4(h->get_info, h, &info_guid,
+ &info_sz, NULL);
+ if (status != EFI_BUFFER_TOO_SMALL) {
+ efi_printk(sys_table_arg, "Failed to get file info size\n");
+ goto close_handles;
+ }
+
+grow:
+ status = efi_call_phys3(sys_table_arg->boottime->allocate_pool,
+ EFI_LOADER_DATA, info_sz,
+ (void **)&info);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to alloc mem for file info\n");
+ goto close_handles;
+ }
+
+ status = efi_call_phys4(h->get_info, h, &info_guid,
+ &info_sz, info);
+ if (status == EFI_BUFFER_TOO_SMALL) {
+ efi_call_phys1(sys_table_arg->boottime->free_pool,
+ info);
+ goto grow;
+ }
+
+ file_sz = info->file_size;
+ efi_call_phys1(sys_table_arg->boottime->free_pool, info);
+
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to get file info\n");
+ goto close_handles;
+ }
+
+ file->size = file_sz;
+ file_size_total += file_sz;
+ }
+
+ if (file_size_total) {
+ unsigned long addr;
+
+ /*
+ * Multiple files need to be at consecutive addresses in memory,
+ * so allocate enough memory for all the files. This is used
+ * for loading multiple files.
+ */
+ status = efi_high_alloc(sys_table_arg, file_size_total, 0x1000,
+ &file_addr, max_addr);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to alloc highmem for files\n");
+ goto close_handles;
+ }
+
+ /* We've run out of free low memory. */
+ if (file_addr > max_addr) {
+ efi_printk(sys_table_arg, "We've run out of free low memory\n");
+ status = EFI_INVALID_PARAMETER;
+ goto free_file_total;
+ }
+
+ addr = file_addr;
+ for (j = 0; j < nr_files; j++) {
+ unsigned long size;
+
+ size = files[j].size;
+ while (size) {
+ unsigned long chunksize;
+ if (size > EFI_READ_CHUNK_SIZE)
+ chunksize = EFI_READ_CHUNK_SIZE;
+ else
+ chunksize = size;
+ status = efi_call_phys3(fh->read,
+ files[j].handle,
+ &chunksize,
+ (void *)addr);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "Failed to read file\n");
+ goto free_file_total;
+ }
+ addr += chunksize;
+ size -= chunksize;
+ }
+
+ efi_call_phys1(fh->close, files[j].handle);
+ }
+
+ }
+
+ efi_call_phys1(sys_table_arg->boottime->free_pool, files);
+
+ *load_addr = file_addr;
+ *load_size = file_size_total;
+
+ return status;
+
+free_file_total:
+ efi_free(sys_table_arg, file_size_total, file_addr);
+
+close_handles:
+ for (k = j; k < i; k++)
+ efi_call_phys1(fh->close, files[k].handle);
+free_files:
+ efi_call_phys1(sys_table_arg->boottime->free_pool, files);
+fail:
+ *load_addr = 0;
+ *load_size = 0;
+
+ return status;
+}
+/*
+ * Relocate a kernel image, either compressed or uncompressed.
+ * In the ARM64 case, all kernel images are currently
+ * uncompressed, and as such when we relocate it we need to
+ * allocate additional space for the BSS segment. Any low
+ * memory that this function should avoid needs to be
+ * unavailable in the EFI memory map, as if the preferred
+ * address is not available the lowest available address will
+ * be used.
+ */
+static efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
+ unsigned long *image_addr,
+ unsigned long image_size,
+ unsigned long alloc_size,
+ unsigned long preferred_addr,
+ unsigned long alignment)
+{
+ unsigned long cur_image_addr;
+ unsigned long new_addr = 0;
+ efi_status_t status;
+ unsigned long nr_pages;
+ efi_physical_addr_t efi_addr = preferred_addr;
+
+ if (!image_addr || !image_size || !alloc_size)
+ return EFI_INVALID_PARAMETER;
+ if (alloc_size < image_size)
+ return EFI_INVALID_PARAMETER;
+
+ cur_image_addr = *image_addr;
+
+ /*
+ * The EFI firmware loader could have placed the kernel image
+ * anywhere in memory, but the kernel has restrictions on the
+ * max physical address it can run at. Some architectures
+ * also have a prefered address, so first try to relocate
+ * to the preferred address. If that fails, allocate as low
+ * as possible while respecting the required alignment.
+ */
+ nr_pages = round_up(alloc_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+ status = efi_call_phys4(sys_table_arg->boottime->allocate_pages,
+ EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+ nr_pages, &efi_addr);
+ new_addr = efi_addr;
+ /*
+ * If preferred address allocation failed allocate as low as
+ * possible.
+ */
+ if (status != EFI_SUCCESS) {
+ status = efi_low_alloc(sys_table_arg, alloc_size, alignment,
+ &new_addr);
+ }
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table_arg, "ERROR: Failed to allocate usable memory for kernel.\n");
+ return status;
+ }
+
+ /*
+ * We know source/dest won't overlap since both memory ranges
+ * have been allocated by UEFI, so we can safely use memcpy.
+ */
+ memcpy((void *)new_addr, (void *)cur_image_addr, image_size);
+
+ /* Return the new address of the relocated image. */
+ *image_addr = new_addr;
+
+ return status;
+}
+
+/*
+ * Convert the unicode UEFI command line to ASCII to pass to kernel.
+ * Size of memory allocated return in *cmd_line_len.
+ * Returns NULL on error.
+ */
+static char *efi_convert_cmdline_to_ascii(efi_system_table_t *sys_table_arg,
+ efi_loaded_image_t *image,
+ int *cmd_line_len)
+{
+ u16 *s2;
+ u8 *s1 = NULL;
+ unsigned long cmdline_addr = 0;
+ int load_options_size = image->load_options_size / 2; /* ASCII */
+ void *options = image->load_options;
+ int options_size = 0;
+ efi_status_t status;
+ int i;
+ u16 zero = 0;
+
+ if (options) {
+ s2 = options;
+ while (*s2 && *s2 != '\n' && options_size < load_options_size) {
+ s2++;
+ options_size++;
+ }
+ }
+
+ if (options_size == 0) {
+ /* No command line options, so return empty string*/
+ options_size = 1;
+ options = &zero;
+ }
+
+ options_size++; /* NUL termination */
+#ifdef CONFIG_ARM
+ /*
+ * For ARM, allocate at a high address to avoid reserved
+ * regions at low addresses that we don't know the specfics of
+ * at the time we are processing the command line.
+ */
+ status = efi_high_alloc(sys_table_arg, options_size, 0,
+ &cmdline_addr, 0xfffff000);
+#else
+ status = efi_low_alloc(sys_table_arg, options_size, 0,
+ &cmdline_addr);
+#endif
+ if (status != EFI_SUCCESS)
+ return NULL;
+
+ s1 = (u8 *)cmdline_addr;
+ s2 = (u16 *)options;
+
+ for (i = 0; i < options_size - 1; i++)
+ *s1++ = *s2++;
+
+ *s1 = '\0';
+
+ *cmd_line_len = options_size;
+ return (char *)cmdline_addr;
+}