--- /dev/null
+/* -----------------------------------------------------------------------
+ *
+ *   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.
+ *
+ * ----------------------------------------------------------------------- */
+
+#include <linux/efi.h>
+#include <asm/efi.h>
+#include <asm/setup.h>
+#include <asm/desc.h>
+
+#include "eboot.h"
+
+static efi_system_table_t *sys_table;
+
+static efi_status_t __get_map(efi_memory_desc_t **map, unsigned long *map_size,
+                             unsigned long *desc_size)
+{
+       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->boottime->allocate_pool,
+                               EFI_LOADER_DATA, *map_size, (void **)&m);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       status = efi_call_phys5(sys_table->boottime->get_memory_map, map_size,
+                               m, &key, desc_size, &desc_version);
+       if (status == EFI_BUFFER_TOO_SMALL) {
+               efi_call_phys1(sys_table->boottime->free_pool, m);
+               goto again;
+       }
+
+       if (status != EFI_SUCCESS)
+               efi_call_phys1(sys_table->boottime->free_pool, m);
+
+fail:
+       *map = m;
+       return status;
+}
+
+/*
+ * Allocate at the highest possible address that is not above 'max'.
+ */
+static efi_status_t high_alloc(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 = __get_map(&map, &map_size, &desc_size);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       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->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;
+       }
+
+free_pool:
+       efi_call_phys1(sys_table->boottime->free_pool, map);
+
+fail:
+       return status;
+}
+
+/*
+ * Allocate at the lowest possible address.
+ */
+static efi_status_t low_alloc(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 = __get_map(&map, &map_size, &desc_size);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       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->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;
+
+free_pool:
+       efi_call_phys1(sys_table->boottime->free_pool, map);
+fail:
+       return status;
+}
+
+static void low_free(unsigned long size, unsigned long addr)
+{
+       unsigned long nr_pages;
+
+       nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+       efi_call_phys2(sys_table->boottime->free_pages, addr, size);
+}
+
+static void find_bits(unsigned long mask, u8 *pos, u8 *size)
+{
+       u8 first, len;
+
+       first = 0;
+       len = 0;
+
+       if (mask) {
+               while (!(mask & 0x1)) {
+                       mask = mask >> 1;
+                       first++;
+               }
+
+               while (mask & 0x1) {
+                       mask = mask >> 1;
+                       len++;
+               }
+       }
+
+       *pos = first;
+       *size = len;
+}
+
+/*
+ * See if we have Graphics Output Protocol
+ */
+static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
+                             unsigned long size)
+{
+       struct efi_graphics_output_protocol *gop, *first_gop;
+       struct efi_pixel_bitmask pixel_info;
+       unsigned long nr_gops;
+       efi_status_t status;
+       void **gop_handle;
+       u16 width, height;
+       u32 fb_base, fb_size;
+       u32 pixels_per_scan_line;
+       int pixel_format;
+       int i;
+
+       status = efi_call_phys3(sys_table->boottime->allocate_pool,
+                               EFI_LOADER_DATA, size, &gop_handle);
+       if (status != EFI_SUCCESS)
+               return status;
+
+       status = efi_call_phys5(sys_table->boottime->locate_handle,
+                               EFI_LOCATE_BY_PROTOCOL, proto,
+                               NULL, &size, gop_handle);
+       if (status != EFI_SUCCESS)
+               goto free_handle;
+
+       first_gop = NULL;
+
+       nr_gops = size / sizeof(void *);
+       for (i = 0; i < nr_gops; i++) {
+               struct efi_graphics_output_mode_info *info;
+               efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
+               void *pciio;
+               void *h = gop_handle[i];
+
+               status = efi_call_phys3(sys_table->boottime->handle_protocol,
+                                       h, proto, &gop);
+               if (status != EFI_SUCCESS)
+                       continue;
+
+               efi_call_phys3(sys_table->boottime->handle_protocol,
+                              h, &pciio_proto, &pciio);
+
+               status = efi_call_phys4(gop->query_mode, gop,
+                                       gop->mode->mode, &size, &info);
+               if (status == EFI_SUCCESS && (!first_gop || pciio)) {
+                       /*
+                        * Apple provide GOPs that are not backed by
+                        * real hardware (they're used to handle
+                        * multiple displays). The workaround is to
+                        * search for a GOP implementing the PCIIO
+                        * protocol, and if one isn't found, to just
+                        * fallback to the first GOP.
+                        */
+                       width = info->horizontal_resolution;
+                       height = info->vertical_resolution;
+                       fb_base = gop->mode->frame_buffer_base;
+                       fb_size = gop->mode->frame_buffer_size;
+                       pixel_format = info->pixel_format;
+                       pixel_info = info->pixel_information;
+                       pixels_per_scan_line = info->pixels_per_scan_line;
+
+                       /*
+                        * Once we've found a GOP supporting PCIIO,
+                        * don't bother looking any further.
+                        */
+                       if (pciio)
+                               break;
+
+                       first_gop = gop;
+               }
+       }
+
+       /* Did we find any GOPs? */
+       if (!first_gop)
+               goto free_handle;
+
+       /* EFI framebuffer */
+       si->orig_video_isVGA = VIDEO_TYPE_EFI;
+
+       si->lfb_width = width;
+       si->lfb_height = height;
+       si->lfb_base = fb_base;
+       si->lfb_size = fb_size;
+       si->pages = 1;
+
+       if (pixel_format == PIXEL_RGB_RESERVED_8BIT_PER_COLOR) {
+               si->lfb_depth = 32;
+               si->lfb_linelength = pixels_per_scan_line * 4;
+               si->red_size = 8;
+               si->red_pos = 0;
+               si->green_size = 8;
+               si->green_pos = 8;
+               si->blue_size = 8;
+               si->blue_pos = 16;
+               si->rsvd_size = 8;
+               si->rsvd_pos = 24;
+       } else if (pixel_format == PIXEL_BGR_RESERVED_8BIT_PER_COLOR) {
+               si->lfb_depth = 32;
+               si->lfb_linelength = pixels_per_scan_line * 4;
+               si->red_size = 8;
+               si->red_pos = 16;
+               si->green_size = 8;
+               si->green_pos = 8;
+               si->blue_size = 8;
+               si->blue_pos = 0;
+               si->rsvd_size = 8;
+               si->rsvd_pos = 24;
+       } else if (pixel_format == PIXEL_BIT_MASK) {
+               find_bits(pixel_info.red_mask, &si->red_pos, &si->red_size);
+               find_bits(pixel_info.green_mask, &si->green_pos,
+                         &si->green_size);
+               find_bits(pixel_info.blue_mask, &si->blue_pos, &si->blue_size);
+               find_bits(pixel_info.reserved_mask, &si->rsvd_pos,
+                         &si->rsvd_size);
+               si->lfb_depth = si->red_size + si->green_size +
+                       si->blue_size + si->rsvd_size;
+               si->lfb_linelength = (pixels_per_scan_line * si->lfb_depth) / 8;
+       } else {
+               si->lfb_depth = 4;
+               si->lfb_linelength = si->lfb_width / 2;
+               si->red_size = 0;
+               si->red_pos = 0;
+               si->green_size = 0;
+               si->green_pos = 0;
+               si->blue_size = 0;
+               si->blue_pos = 0;
+               si->rsvd_size = 0;
+               si->rsvd_pos = 0;
+       }
+
+free_handle:
+       efi_call_phys1(sys_table->boottime->free_pool, gop_handle);
+       return status;
+}
+
+/*
+ * See if we have Universal Graphics Adapter (UGA) protocol
+ */
+static efi_status_t setup_uga(struct screen_info *si, efi_guid_t *uga_proto,
+                             unsigned long size)
+{
+       struct efi_uga_draw_protocol *uga, *first_uga;
+       unsigned long nr_ugas;
+       efi_status_t status;
+       u32 width, height;
+       void **uga_handle = NULL;
+       int i;
+
+       status = efi_call_phys3(sys_table->boottime->allocate_pool,
+                               EFI_LOADER_DATA, size, &uga_handle);
+       if (status != EFI_SUCCESS)
+               return status;
+
+       status = efi_call_phys5(sys_table->boottime->locate_handle,
+                               EFI_LOCATE_BY_PROTOCOL, uga_proto,
+                               NULL, &size, uga_handle);
+       if (status != EFI_SUCCESS)
+               goto free_handle;
+
+       first_uga = NULL;
+
+       nr_ugas = size / sizeof(void *);
+       for (i = 0; i < nr_ugas; i++) {
+               efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
+               void *handle = uga_handle[i];
+               u32 w, h, depth, refresh;
+               void *pciio;
+
+               status = efi_call_phys3(sys_table->boottime->handle_protocol,
+                                       handle, uga_proto, &uga);
+               if (status != EFI_SUCCESS)
+                       continue;
+
+               efi_call_phys3(sys_table->boottime->handle_protocol,
+                              handle, &pciio_proto, &pciio);
+
+               status = efi_call_phys5(uga->get_mode, uga, &w, &h,
+                                       &depth, &refresh);
+               if (status == EFI_SUCCESS && (!first_uga || pciio)) {
+                       width = w;
+                       height = h;
+
+                       /*
+                        * Once we've found a UGA supporting PCIIO,
+                        * don't bother looking any further.
+                        */
+                       if (pciio)
+                               break;
+
+                       first_uga = uga;
+               }
+       }
+
+       if (!first_uga)
+               goto free_handle;
+
+       /* EFI framebuffer */
+       si->orig_video_isVGA = VIDEO_TYPE_EFI;
+
+       si->lfb_depth = 32;
+       si->lfb_width = width;
+       si->lfb_height = height;
+
+       si->red_size = 8;
+       si->red_pos = 16;
+       si->green_size = 8;
+       si->green_pos = 8;
+       si->blue_size = 8;
+       si->blue_pos = 0;
+       si->rsvd_size = 8;
+       si->rsvd_pos = 24;
+
+
+free_handle:
+       efi_call_phys1(sys_table->boottime->free_pool, uga_handle);
+       return status;
+}
+
+void setup_graphics(struct boot_params *boot_params)
+{
+       efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+       struct screen_info *si;
+       efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
+       efi_status_t status;
+       unsigned long size;
+       void **gop_handle = NULL;
+       void **uga_handle = NULL;
+
+       si = &boot_params->screen_info;
+       memset(si, 0, sizeof(*si));
+
+       size = 0;
+       status = efi_call_phys5(sys_table->boottime->locate_handle,
+                               EFI_LOCATE_BY_PROTOCOL, &graphics_proto,
+                               NULL, &size, gop_handle);
+       if (status == EFI_BUFFER_TOO_SMALL)
+               status = setup_gop(si, &graphics_proto, size);
+
+       if (status != EFI_SUCCESS) {
+               size = 0;
+               status = efi_call_phys5(sys_table->boottime->locate_handle,
+                                       EFI_LOCATE_BY_PROTOCOL, &uga_proto,
+                                       NULL, &size, uga_handle);
+               if (status == EFI_BUFFER_TOO_SMALL)
+                       setup_uga(si, &uga_proto, size);
+       }
+}
+
+struct initrd {
+       efi_file_handle_t *handle;
+       u64 size;
+};
+
+/*
+ * Check the cmdline for a LILO-style initrd= arguments.
+ *
+ * We only support loading an initrd from the same filesystem as the
+ * kernel image.
+ */
+static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
+                                   struct setup_header *hdr)
+{
+       struct initrd *initrds;
+       unsigned long initrd_addr;
+       efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+       u64 initrd_total;
+       efi_file_io_interface_t *io;
+       efi_file_handle_t *fh;
+       efi_status_t status;
+       int nr_initrds;
+       char *str;
+       int i, j, k;
+
+       initrd_addr = 0;
+       initrd_total = 0;
+
+       str = (char *)(unsigned long)hdr->cmd_line_ptr;
+
+       j = 0;                  /* See close_handles */
+
+       if (!str || !*str)
+               return EFI_SUCCESS;
+
+       for (nr_initrds = 0; *str; nr_initrds++) {
+               str = strstr(str, "initrd=");
+               if (!str)
+                       break;
+
+               str += 7;
+
+               /* Skip any leading slashes */
+               while (*str == '/' || *str == '\\')
+                       str++;
+
+               while (*str && *str != ' ' && *str != '\n')
+                       str++;
+       }
+
+       if (!nr_initrds)
+               return EFI_SUCCESS;
+
+       status = efi_call_phys3(sys_table->boottime->allocate_pool,
+                               EFI_LOADER_DATA,
+                               nr_initrds * sizeof(*initrds),
+                               &initrds);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       str = (char *)(unsigned long)hdr->cmd_line_ptr;
+       for (i = 0; i < nr_initrds; i++) {
+               struct initrd *initrd;
+               efi_file_handle_t *h;
+               efi_file_info_t *info;
+               efi_char16_t filename[256];
+               unsigned long info_sz;
+               efi_guid_t info_guid = EFI_FILE_INFO_ID;
+               efi_char16_t *p;
+               u64 file_sz;
+
+               str = strstr(str, "initrd=");
+               if (!str)
+                       break;
+
+               str += 7;
+
+               initrd = &initrds[i];
+               p = filename;
+
+               /* Skip any leading slashes */
+               while (*str == '/' || *str == '\\')
+                       str++;
+
+               while (*str && *str != ' ' && *str != '\n') {
+                       if (p >= filename + sizeof(filename))
+                               break;
+
+                       *p++ = *str++;
+               }
+
+               *p = '\0';
+
+               /* Only open the volume once. */
+               if (!i) {
+                       efi_boot_services_t *boottime;
+
+                       boottime = sys_table->boottime;
+
+                       status = efi_call_phys3(boottime->handle_protocol,
+                                       image->device_handle, &fs_proto, &io);
+                       if (status != EFI_SUCCESS)
+                               goto free_initrds;
+
+                       status = efi_call_phys2(io->open_volume, io, &fh);
+                       if (status != EFI_SUCCESS)
+                               goto free_initrds;
+               }
+
+               status = efi_call_phys5(fh->open, fh, &h, filename,
+                                       EFI_FILE_MODE_READ, (u64)0);
+               if (status != EFI_SUCCESS)
+                       goto close_handles;
+
+               initrd->handle = h;
+
+               info_sz = 0;
+               status = efi_call_phys4(h->get_info, h, &info_guid,
+                                       &info_sz, NULL);
+               if (status != EFI_BUFFER_TOO_SMALL)
+                       goto close_handles;
+
+grow:
+               status = efi_call_phys3(sys_table->boottime->allocate_pool,
+                                       EFI_LOADER_DATA, info_sz, &info);
+               if (status != EFI_SUCCESS)
+                       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->boottime->free_pool, info);
+                       goto grow;
+               }
+
+               file_sz = info->file_size;
+               efi_call_phys1(sys_table->boottime->free_pool, info);
+
+               if (status != EFI_SUCCESS)
+                       goto close_handles;
+
+               initrd->size = file_sz;
+               initrd_total += file_sz;
+       }
+
+       if (initrd_total) {
+               unsigned long addr;
+
+               /*
+                * Multiple initrd's need to be at consecutive
+                * addresses in memory, so allocate enough memory for
+                * all the initrd's.
+                */
+               status = high_alloc(initrd_total, 0x1000,
+                                  &initrd_addr, hdr->initrd_addr_max);
+               if (status != EFI_SUCCESS)
+                       goto close_handles;
+
+               /* We've run out of free low memory. */
+               if (initrd_addr > hdr->initrd_addr_max) {
+                       status = EFI_INVALID_PARAMETER;
+                       goto free_initrd_total;
+               }
+
+               addr = initrd_addr;
+               for (j = 0; j < nr_initrds; j++) {
+                       u64 size;
+
+                       size = initrds[j].size;
+                       status = efi_call_phys3(fh->read, initrds[j].handle,
+                                               &size, addr);
+                       if (status != EFI_SUCCESS)
+                               goto free_initrd_total;
+
+                       efi_call_phys1(fh->close, initrds[j].handle);
+
+                       addr += size;
+               }
+
+       }
+
+       efi_call_phys1(sys_table->boottime->free_pool, initrds);
+
+       hdr->ramdisk_image = initrd_addr;
+       hdr->ramdisk_size = initrd_total;
+
+       return status;
+
+free_initrd_total:
+       low_free(initrd_total, initrd_addr);
+
+close_handles:
+       for (k = j; k < nr_initrds; k++)
+               efi_call_phys1(fh->close, initrds[k].handle);
+free_initrds:
+       efi_call_phys1(sys_table->boottime->free_pool, initrds);
+fail:
+       hdr->ramdisk_image = 0;
+       hdr->ramdisk_size = 0;
+
+       return status;
+}
+
+/*
+ * Because the x86 boot code expects to be passed a boot_params we
+ * need to create one ourselves (usually the bootloader would create
+ * one for us).
+ */
+static efi_status_t make_boot_params(struct boot_params *boot_params,
+                                    efi_loaded_image_t *image,
+                                    void *handle)
+{
+       struct efi_info *efi = &boot_params->efi_info;
+       struct apm_bios_info *bi = &boot_params->apm_bios_info;
+       struct sys_desc_table *sdt = &boot_params->sys_desc_table;
+       struct e820entry *e820_map = &boot_params->e820_map[0];
+       struct e820entry *prev = NULL;
+       struct setup_header *hdr = &boot_params->hdr;
+       unsigned long size, key, desc_size, _size;
+       efi_memory_desc_t *mem_map;
+       void *options = image->load_options;
+       u32 load_options_size = image->load_options_size / 2; /* ASCII */
+       int options_size = 0;
+       efi_status_t status;
+       __u32 desc_version;
+       unsigned long cmdline;
+       u8 nr_entries;
+       u16 *s2;
+       u8 *s1;
+       int i;
+
+       hdr->type_of_loader = 0x21;
+
+       /* Convert unicode cmdline to ascii */
+       cmdline = 0;
+       s2 = (u16 *)options;
+
+       if (s2) {
+               while (*s2 && *s2 != '\n' && options_size < load_options_size) {
+                       s2++;
+                       options_size++;
+               }
+
+               if (options_size) {
+                       if (options_size > hdr->cmdline_size)
+                               options_size = hdr->cmdline_size;
+
+                       options_size++; /* NUL termination */
+
+                       status = low_alloc(options_size, 1, &cmdline);
+                       if (status != EFI_SUCCESS)
+                               goto fail;
+
+                       s1 = (u8 *)(unsigned long)cmdline;
+                       s2 = (u16 *)options;
+
+                       for (i = 0; i < options_size - 1; i++)
+                               *s1++ = *s2++;
+
+                       *s1 = '\0';
+               }
+       }
+
+       hdr->cmd_line_ptr = cmdline;
+
+       hdr->ramdisk_image = 0;
+       hdr->ramdisk_size = 0;
+
+       status = handle_ramdisks(image, hdr);
+       if (status != EFI_SUCCESS)
+               goto free_cmdline;
+
+       setup_graphics(boot_params);
+
+       /* Clear APM BIOS info */
+       memset(bi, 0, sizeof(*bi));
+
+       memset(sdt, 0, sizeof(*sdt));
+
+       memcpy(&efi->efi_loader_signature, EFI_LOADER_SIGNATURE, sizeof(__u32));
+
+       size = sizeof(*mem_map) * 32;
+
+again:
+       size += sizeof(*mem_map);
+       _size = size;
+       status = low_alloc(size, 1, (unsigned long *)&mem_map);
+       if (status != EFI_SUCCESS)
+               goto free_cmdline;
+
+       status = efi_call_phys5(sys_table->boottime->get_memory_map, &size,
+                               mem_map, &key, &desc_size, &desc_version);
+       if (status == EFI_BUFFER_TOO_SMALL) {
+               low_free(_size, (unsigned long)mem_map);
+               goto again;
+       }
+
+       if (status != EFI_SUCCESS)
+               goto free_mem_map;
+
+       efi->efi_systab = (unsigned long)sys_table;
+       efi->efi_memdesc_size = desc_size;
+       efi->efi_memdesc_version = desc_version;
+       efi->efi_memmap = (unsigned long)mem_map;
+       efi->efi_memmap_size = size;
+
+#ifdef CONFIG_X86_64
+       efi->efi_systab_hi = (unsigned long)sys_table >> 32;
+       efi->efi_memmap_hi = (unsigned long)mem_map >> 32;
+#endif
+
+       /* Might as well exit boot services now */
+       status = efi_call_phys2(sys_table->boottime->exit_boot_services,
+                               handle, key);
+       if (status != EFI_SUCCESS)
+               goto free_mem_map;
+
+       /* Historic? */
+       boot_params->alt_mem_k = 32 * 1024;
+
+       /*
+        * Convert the EFI memory map to E820.
+        */
+       nr_entries = 0;
+       for (i = 0; i < size / desc_size; i++) {
+               efi_memory_desc_t *d;
+               unsigned int e820_type = 0;
+               unsigned long m = (unsigned long)mem_map;
+
+               d = (efi_memory_desc_t *)(m + (i * desc_size));
+               switch (d->type) {
+               case EFI_RESERVED_TYPE:
+               case EFI_RUNTIME_SERVICES_CODE:
+               case EFI_RUNTIME_SERVICES_DATA:
+               case EFI_MEMORY_MAPPED_IO:
+               case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
+               case EFI_PAL_CODE:
+                       e820_type = E820_RESERVED;
+                       break;
+
+               case EFI_UNUSABLE_MEMORY:
+                       e820_type = E820_UNUSABLE;
+                       break;
+
+               case EFI_ACPI_RECLAIM_MEMORY:
+                       e820_type = E820_ACPI;
+                       break;
+
+               case EFI_LOADER_CODE:
+               case EFI_LOADER_DATA:
+               case EFI_BOOT_SERVICES_CODE:
+               case EFI_BOOT_SERVICES_DATA:
+               case EFI_CONVENTIONAL_MEMORY:
+                       e820_type = E820_RAM;
+                       break;
+
+               case EFI_ACPI_MEMORY_NVS:
+                       e820_type = E820_NVS;
+                       break;
+
+               default:
+                       continue;
+               }
+
+               /* Merge adjacent mappings */
+               if (prev && prev->type == e820_type &&
+                   (prev->addr + prev->size) == d->phys_addr)
+                       prev->size += d->num_pages << 12;
+               else {
+                       e820_map->addr = d->phys_addr;
+                       e820_map->size = d->num_pages << 12;
+                       e820_map->type = e820_type;
+                       prev = e820_map++;
+                       nr_entries++;
+               }
+       }
+
+       boot_params->e820_entries = nr_entries;
+
+       return EFI_SUCCESS;
+
+free_mem_map:
+       low_free(_size, (unsigned long)mem_map);
+free_cmdline:
+       if (options_size)
+               low_free(options_size, hdr->cmd_line_ptr);
+fail:
+       return status;
+}
+
+/*
+ * On success we return a pointer to a boot_params structure, and NULL
+ * on failure.
+ */
+struct boot_params *efi_main(void *handle, efi_system_table_t *_table)
+{
+       struct boot_params *boot_params;
+       unsigned long start, nr_pages;
+       struct desc_ptr *gdt, *idt;
+       efi_loaded_image_t *image;
+       struct setup_header *hdr;
+       efi_status_t status;
+       efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
+       struct desc_struct *desc;
+
+       sys_table = _table;
+
+       /* Check if we were booted by the EFI firmware */
+       if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+               goto fail;
+
+       status = efi_call_phys3(sys_table->boottime->handle_protocol,
+                               handle, &proto, (void *)&image);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       status = low_alloc(0x4000, 1, (unsigned long *)&boot_params);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       memset(boot_params, 0x0, 0x4000);
+
+       /* Copy first two sectors to boot_params */
+       memcpy(boot_params, image->image_base, 1024);
+
+       hdr = &boot_params->hdr;
+
+       /*
+        * The EFI firmware loader could have placed the kernel image
+        * anywhere in memory, but the kernel has various restrictions
+        * on the max physical address it can run at. Attempt to move
+        * the kernel to boot_params.pref_address, or as low as
+        * possible.
+        */
+       start = hdr->pref_address;
+       nr_pages = round_up(hdr->init_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+
+       status = efi_call_phys4(sys_table->boottime->allocate_pages,
+                               EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+                               nr_pages, &start);
+       if (status != EFI_SUCCESS) {
+               status = low_alloc(hdr->init_size, hdr->kernel_alignment,
+                                  &start);
+               if (status != EFI_SUCCESS)
+                       goto fail;
+       }
+
+       hdr->code32_start = (__u32)start;
+       hdr->pref_address = (__u64)(unsigned long)image->image_base;
+
+       memcpy((void *)start, image->image_base, image->image_size);
+
+       status = efi_call_phys3(sys_table->boottime->allocate_pool,
+                               EFI_LOADER_DATA, sizeof(*gdt),
+                               (void **)&gdt);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       gdt->size = 0x800;
+       status = low_alloc(gdt->size, 8, (unsigned long *)&gdt->address);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       status = efi_call_phys3(sys_table->boottime->allocate_pool,
+                               EFI_LOADER_DATA, sizeof(*idt),
+                               (void **)&idt);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       idt->size = 0;
+       idt->address = 0;
+
+       status = make_boot_params(boot_params, image, handle);
+       if (status != EFI_SUCCESS)
+               goto fail;
+
+       memset((char *)gdt->address, 0x0, gdt->size);
+       desc = (struct desc_struct *)gdt->address;
+
+       /* The first GDT is a dummy and the second is unused. */
+       desc += 2;
+
+       desc->limit0 = 0xffff;
+       desc->base0 = 0x0000;
+       desc->base1 = 0x0000;
+       desc->type = SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
+       desc->s = DESC_TYPE_CODE_DATA;
+       desc->dpl = 0;
+       desc->p = 1;
+       desc->limit = 0xf;
+       desc->avl = 0;
+       desc->l = 0;
+       desc->d = SEG_OP_SIZE_32BIT;
+       desc->g = SEG_GRANULARITY_4KB;
+       desc->base2 = 0x00;
+
+       desc++;
+       desc->limit0 = 0xffff;
+       desc->base0 = 0x0000;
+       desc->base1 = 0x0000;
+       desc->type = SEG_TYPE_DATA | SEG_TYPE_READ_WRITE;
+       desc->s = DESC_TYPE_CODE_DATA;
+       desc->dpl = 0;
+       desc->p = 1;
+       desc->limit = 0xf;
+       desc->avl = 0;
+       desc->l = 0;
+       desc->d = SEG_OP_SIZE_32BIT;
+       desc->g = SEG_GRANULARITY_4KB;
+       desc->base2 = 0x00;
+
+#ifdef CONFIG_X86_64
+       /* Task segment value */
+       desc++;
+       desc->limit0 = 0x0000;
+       desc->base0 = 0x0000;
+       desc->base1 = 0x0000;
+       desc->type = SEG_TYPE_TSS;
+       desc->s = 0;
+       desc->dpl = 0;
+       desc->p = 1;
+       desc->limit = 0x0;
+       desc->avl = 0;
+       desc->l = 0;
+       desc->d = 0;
+       desc->g = SEG_GRANULARITY_4KB;
+       desc->base2 = 0x00;
+#endif /* CONFIG_X86_64 */
+
+       asm volatile ("lidt %0" : : "m" (*idt));
+       asm volatile ("lgdt %0" : : "m" (*gdt));
+
+       asm volatile("cli");
+
+       return boot_params;
+fail:
+       return NULL;
+}