grub2/0006-Add-support-for-EFI-handover-on-ARM64.patch

From 17667c24295a4b105bf20a3bd5bb19ef0acaebba Mon Sep 17 00:00:00 2001
From: Matthew Garrett <mjg@redhat.com>
Date: Fri, 21 Dec 2018 14:36:10 +0800
Subject: [PATCH 6/6] Add support for EFI handover on ARM64

Add support for EFI handover on ARM64 for loading linux kernel.
---
 grub-core/Makefile.core.def        |   9 +-
 grub-core/loader/arm64/efi/linux.c | 448 +++++++++++++++++++++++++++++++++++++
 2 files changed, 453 insertions(+), 4 deletions(-)
 create mode 100644 grub-core/loader/arm64/efi/linux.c

diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 1269f372c..f306311e6 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -1761,10 +1761,11 @@ module = {
 
 module = {
   name = linuxefi;
-  efi = loader/i386/efi/linux.c;
-  efi = lib/cmdline.c;
-  enable = i386_efi;
-  enable = x86_64_efi;
+  arm64 = loader/arm64/efi/linux.c;
+  x86_64 = loader/i386/efi/linux.c;
+  common = lib/cmdline.c;
+  enable = x86_64;
+  enable = arm64;
 };
 
 module = {
diff --git a/grub-core/loader/arm64/efi/linux.c b/grub-core/loader/arm64/efi/linux.c
new file mode 100644
index 000000000..4a5c70e4b
--- /dev/null
+++ b/grub-core/loader/arm64/efi/linux.c
@@ -0,0 +1,448 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2013  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/charset.h>
+#include <grub/command.h>
+#include <grub/err.h>
+#include <grub/file.h>
+#include <grub/fdt.h>
+#include <grub/linux.h>
+#include <grub/loader.h>
+#include <grub/mm.h>
+#include <grub/types.h>
+#include <grub/cpu/linux.h>
+#include <grub/efi/efi.h>
+#include <grub/cpu/fdtload.h>
+#include <grub/efi/memory.h>
+#include <grub/efi/pe32.h>
+#include <grub/i18n.h>
+#include <grub/lib/cmdline.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+static grub_dl_t my_mod;
+static int loaded;
+
+static void *kernel_addr;
+static grub_uint64_t kernel_size;
+static grub_uint32_t handover_offset;
+
+static char *linux_args;
+static grub_uint32_t cmdline_size;
+
+static grub_addr_t initrd_start;
+static grub_addr_t initrd_end;
+
+struct grub_arm64_linux_pe_header
+{
+  grub_uint32_t magic;
+  struct grub_pe32_coff_header coff;
+  struct grub_pe64_optional_header opt;
+};
+
+#if defined(__aarch64__)
+# define GRUB_LINUX_ARMXX_MAGIC_SIGNATURE GRUB_ARM64_LINUX_MAGIC
+# define linux_armxx_kernel_header grub_arm64_linux_kernel_header
+# define grub_armxx_linux_pe_header grub_arm64_linux_pe_header
+#endif
+
+#define SHIM_LOCK_GUID \
+ { 0x605dab50, 0xe046, 0x4300, {0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23} }
+
+struct grub_efi_shim_lock
+{
+  grub_efi_status_t (*verify) (void *buffer, grub_uint32_t size);
+};
+typedef struct grub_efi_shim_lock grub_efi_shim_lock_t;
+
+static grub_efi_boolean_t
+grub_linuxefi_secure_validate (void *data, grub_uint32_t size)
+{
+  grub_efi_guid_t guid = SHIM_LOCK_GUID;
+  grub_efi_shim_lock_t *shim_lock;
+
+  shim_lock = grub_efi_locate_protocol(&guid, NULL);
+
+  if (!shim_lock)
+    return 1;
+
+  if (shim_lock->verify(data, size) == GRUB_EFI_SUCCESS)
+    return 1;
+
+  return 0;
+}
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-align"
+
+typedef void (*handover_func) (void *, grub_efi_system_table_t *, void *);
+
+static grub_err_t
+grub_efi_linux_boot (void *kernel_address, grub_off_t offset,
+		     void *kernel_params)
+{
+  handover_func hf;
+
+  hf = (handover_func)((char *)kernel_address + offset);
+  hf (grub_efi_image_handle, grub_efi_system_table, kernel_params);
+
+  return GRUB_ERR_BUG;
+}
+
+#pragma GCC diagnostic pop
+static grub_err_t
+grub_armxx_efi_linux_check_image (struct linux_armxx_kernel_header * lh)
+{
+  if (lh->magic != GRUB_LINUX_ARMXX_MAGIC_SIGNATURE)
+    return grub_error(GRUB_ERR_BAD_OS, "invalid magic number");
+
+  if ((lh->code0 & 0xffff) != GRUB_EFI_PE_MAGIC)
+    return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+		       N_("plain image kernel not supported - rebuild with CONFIG_(U)EFI_STUB enabled"));
+
+  grub_dprintf ("linux", "UEFI stub kernel:\n");
+  grub_dprintf ("linux", "PE/COFF header @ %08x\n", lh->hdr_offset);
+
+  return GRUB_ERR_NONE;
+}
+
+static grub_err_t
+finalize_params_linux (void)
+{
+  grub_efi_loaded_image_t *loaded_image = NULL;
+  int node, retval, len;
+
+  void *fdt;
+
+  fdt = grub_fdt_load (0x400);
+
+  if (!fdt)
+    goto failure;
+
+  node = grub_fdt_find_subnode (fdt, 0, "chosen");
+  if (node < 0)
+    node = grub_fdt_add_subnode (fdt, 0, "chosen");
+
+  if (node < 1)
+    goto failure;
+
+  /* Set initrd info */
+  if (initrd_start && initrd_end > initrd_start)
+    {
+      grub_dprintf ("linux", "Initrd @ %p-%p\n",
+		    (void *) initrd_start, (void *) initrd_end);
+
+      retval = grub_fdt_set_prop64 (fdt, node, "linux,initrd-start",
+				    initrd_start);
+      if (retval)
+	goto failure;
+      retval = grub_fdt_set_prop64 (fdt, node, "linux,initrd-end",
+				    initrd_end);
+      if (retval)
+	goto failure;
+    }
+
+  if (grub_fdt_install() != GRUB_ERR_NONE)
+    goto failure;
+
+  grub_dprintf ("linux", "Installed/updated FDT configuration table @ %p\n",
+		fdt);
+
+  /* Convert command line to UCS-2 */
+  loaded_image = grub_efi_get_loaded_image (grub_efi_image_handle);
+  if (!loaded_image)
+    goto failure;
+
+  loaded_image->load_options_size = len =
+    (grub_strlen (linux_args) + 1) * sizeof (grub_efi_char16_t);
+  loaded_image->load_options =
+    grub_efi_allocate_any_pages (GRUB_EFI_BYTES_TO_PAGES (loaded_image->load_options_size));
+  if (!loaded_image->load_options)
+    return grub_error(GRUB_ERR_BAD_OS, "failed to create kernel parameters");
+
+  loaded_image->load_options_size =
+    2 * grub_utf8_to_utf16 (loaded_image->load_options, len,
+			    (grub_uint8_t *) linux_args, len, NULL);
+
+  return GRUB_ERR_NONE;
+
+failure:
+  grub_fdt_unload();
+  return grub_error(GRUB_ERR_BAD_OS, "failed to install/update FDT");
+}
+
+static void
+free_params (void)
+{
+  grub_efi_loaded_image_t *loaded_image = NULL;
+
+  loaded_image = grub_efi_get_loaded_image (grub_efi_image_handle);
+  if (loaded_image)
+    {
+      if (loaded_image->load_options)
+	grub_efi_free_pages ((grub_efi_physical_address_t)(grub_efi_uintn_t)loaded_image->load_options,
+			     GRUB_EFI_BYTES_TO_PAGES (loaded_image->load_options_size));
+      loaded_image->load_options = NULL;
+      loaded_image->load_options_size = 0;
+    }
+}
+
+static grub_err_t
+grub_armxx_efi_linux_boot_image (grub_addr_t addr, char *args)
+{
+  grub_err_t retval;
+
+  retval = finalize_params_linux ();
+  if (retval != GRUB_ERR_NONE)
+    return grub_errno;
+
+  grub_dprintf ("linux", "linux command line: '%s'\n", args);
+
+  retval = grub_efi_linux_boot ((char *)addr, handover_offset, (void *)addr);
+
+  /* Never reached... */
+  free_params();
+  return retval;
+}
+
+static grub_err_t
+grub_linux_boot (void)
+{
+  return grub_armxx_efi_linux_boot_image((grub_addr_t)kernel_addr, linux_args);
+}
+
+static grub_err_t
+grub_linux_unload (void)
+{
+  grub_dl_unref (my_mod);
+  loaded = 0;
+  if (initrd_start)
+    grub_efi_free_pages ((grub_efi_physical_address_t) initrd_start,
+			 GRUB_EFI_BYTES_TO_PAGES (initrd_end - initrd_start));
+  initrd_start = initrd_end = 0;
+  grub_free (linux_args);
+  if (kernel_addr)
+    grub_efi_free_pages ((grub_addr_t) kernel_addr,
+			 GRUB_EFI_BYTES_TO_PAGES (kernel_size));
+  grub_fdt_unload ();
+  return GRUB_ERR_NONE;
+}
+
+/*
+ * As per linux/Documentation/arm/Booting
+ * ARM initrd needs to be covered by kernel linear mapping,
+ * so place it in the first 512MB of DRAM.
+ *
+ * As per linux/Documentation/arm64/booting.txt
+ * ARM64 initrd needs to be contained entirely within a 1GB aligned window
+ * of up to 32GB of size that covers the kernel image as well.
+ * Since the EFI stub loader will attempt to load the kernel near start of
+ * RAM, place the buffer in the first 32GB of RAM.
+ */
+#ifdef __arm__
+#define INITRD_MAX_ADDRESS_OFFSET (512U * 1024 * 1024)
+#else /* __aarch64__ */
+#define INITRD_MAX_ADDRESS_OFFSET (32ULL * 1024 * 1024 * 1024)
+#endif
+
+/*
+ * This function returns a pointer to a legally allocated initrd buffer,
+ * or NULL if unsuccessful
+ */
+static void *
+allocate_initrd_mem (int initrd_pages)
+{
+  grub_addr_t max_addr;
+
+  if (grub_efi_get_ram_base (&max_addr) != GRUB_ERR_NONE)
+    return NULL;
+
+  max_addr += INITRD_MAX_ADDRESS_OFFSET - 1;
+
+  return grub_efi_allocate_pages_real (max_addr, initrd_pages,
+				       GRUB_EFI_ALLOCATE_MAX_ADDRESS,
+				       GRUB_EFI_LOADER_DATA);
+}
+
+static grub_err_t
+grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
+		 int argc, char *argv[])
+{
+  struct grub_linux_initrd_context initrd_ctx = { 0, 0, 0 };
+  int initrd_size, initrd_pages;
+  void *initrd_mem = NULL;
+
+  if (argc == 0)
+    {
+      grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
+      goto fail;
+    }
+
+  if (!loaded)
+    {
+      grub_error (GRUB_ERR_BAD_ARGUMENT,
+		  N_("you need to load the kernel first"));
+      goto fail;
+    }
+
+  if (grub_initrd_init (argc, argv, &initrd_ctx))
+    goto fail;
+
+  initrd_size = grub_get_initrd_size (&initrd_ctx);
+  grub_dprintf ("linux", "Loading initrd\n");
+
+  initrd_pages = (GRUB_EFI_BYTES_TO_PAGES (initrd_size));
+  initrd_mem = allocate_initrd_mem (initrd_pages);
+
+  if (!initrd_mem)
+    {
+      grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
+      goto fail;
+    }
+
+  if (grub_initrd_load (&initrd_ctx, argv, initrd_mem))
+    goto fail;
+
+  initrd_start = (grub_addr_t) initrd_mem;
+  initrd_end = initrd_start + initrd_size;
+  grub_dprintf ("linux", "[addr=%p, size=0x%x]\n",
+		(void *) initrd_start, initrd_size);
+
+ fail:
+  grub_initrd_close (&initrd_ctx);
+  if (initrd_mem && !initrd_start)
+    grub_efi_free_pages ((grub_addr_t) initrd_mem, initrd_pages);
+
+  return grub_errno;
+}
+
+static grub_err_t
+grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
+		int argc, char *argv[])
+{
+  grub_file_t file = 0;
+  struct linux_armxx_kernel_header lh;
+  struct grub_armxx_linux_pe_header *pe;
+
+  grub_dl_ref (my_mod);
+
+  if (argc == 0)
+    {
+      grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
+      goto fail;
+    }
+
+  file = grub_file_open (argv[0]);
+  if (!file)
+    goto fail;
+
+  kernel_size = grub_file_size (file);
+
+  if (grub_file_read (file, &lh, sizeof (lh)) < (long) sizeof (lh))
+    return grub_errno;
+
+  if (grub_armxx_efi_linux_check_image (&lh) != GRUB_ERR_NONE)
+    goto fail;
+
+  grub_loader_unset();
+
+  grub_dprintf ("linux", "kernel file size: %lld\n", (long long) kernel_size);
+  kernel_addr = grub_efi_allocate_any_pages (GRUB_EFI_BYTES_TO_PAGES (kernel_size));
+  grub_dprintf ("linux", "kernel numpages: %lld\n",
+		(long long) GRUB_EFI_BYTES_TO_PAGES (kernel_size));
+  if (!kernel_addr)
+    {
+      grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
+      goto fail;
+    }
+
+  grub_file_seek (file, 0);
+  if (grub_file_read (file, kernel_addr, kernel_size)
+      < (grub_int64_t) kernel_size)
+    {
+      if (!grub_errno)
+	grub_error (GRUB_ERR_BAD_OS, N_("premature end of file %s"), argv[0]);
+      goto fail;
+    }
+
+  grub_dprintf ("linux", "kernel @ %p\n", kernel_addr);
+
+  if (!grub_linuxefi_secure_validate (kernel_addr, kernel_size))
+    {
+      grub_error (GRUB_ERR_INVALID_COMMAND, N_("%s has invalid signature"), argv[0]);
+      goto fail;
+    }
+
+  pe = (void *)((unsigned long)kernel_addr + lh.hdr_offset);
+  handover_offset = pe->opt.entry_addr;
+
+  cmdline_size = grub_loader_cmdline_size (argc, argv) + sizeof (LINUX_IMAGE);
+  linux_args = grub_malloc (cmdline_size);
+  if (!linux_args)
+    {
+      grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
+      goto fail;
+    }
+  grub_memcpy (linux_args, LINUX_IMAGE, sizeof (LINUX_IMAGE));
+  grub_create_loader_cmdline (argc, argv,
+			      linux_args + sizeof (LINUX_IMAGE) - 1,
+			      cmdline_size);
+
+  if (grub_errno == GRUB_ERR_NONE)
+    {
+      grub_loader_set (grub_linux_boot, grub_linux_unload, 0);
+      loaded = 1;
+    }
+
+fail:
+  if (file)
+    grub_file_close (file);
+
+  if (grub_errno != GRUB_ERR_NONE)
+    {
+      grub_dl_unref (my_mod);
+      loaded = 0;
+    }
+
+  if (linux_args && !loaded)
+    grub_free (linux_args);
+
+  if (kernel_addr && !loaded)
+    grub_efi_free_pages ((grub_addr_t) kernel_addr,
+			 GRUB_EFI_BYTES_TO_PAGES (kernel_size));
+
+  return grub_errno;
+}
+
+
+static grub_command_t cmd_linux, cmd_initrd;
+
+GRUB_MOD_INIT (linux)
+{
+  cmd_linux = grub_register_command ("linuxefi", grub_cmd_linux, 0,
+				     N_("Load Linux."));
+  cmd_initrd = grub_register_command ("initrdefi", grub_cmd_initrd, 0,
+				      N_("Load initrd."));
+  my_mod = mod;
+}
+
+GRUB_MOD_FINI (linux)
+{
+  grub_unregister_command (cmd_linux);
+  grub_unregister_command (cmd_initrd);
+}
-- 
2.16.4