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-rw-r--r--drivers/firmware/efi/libstub/Makefile62
-rw-r--r--drivers/firmware/efi/libstub/arm-stub.c213
-rw-r--r--drivers/firmware/efi/libstub/arm32-stub.c139
-rw-r--r--drivers/firmware/efi/libstub/arm64-stub.c141
-rw-r--r--drivers/firmware/efi/libstub/efi-stub-helper.c182
-rw-r--r--drivers/firmware/efi/libstub/efistub.h21
-rw-r--r--drivers/firmware/efi/libstub/fdt.c103
-rw-r--r--drivers/firmware/efi/libstub/gop.c354
-rw-r--r--drivers/firmware/efi/libstub/random.c143
-rw-r--r--drivers/firmware/efi/libstub/string.c57
10 files changed, 1281 insertions, 134 deletions
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 280bc0a63..c06945160 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -8,23 +8,40 @@ cflags-$(CONFIG_X86_32) := -march=i386
cflags-$(CONFIG_X86_64) := -mcmodel=small
cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 \
-fPIC -fno-strict-aliasing -mno-red-zone \
- -mno-mmx -mno-sse -DDISABLE_BRANCH_PROFILING
+ -mno-mmx -mno-sse
cflags-$(CONFIG_ARM64) := $(subst -pg,,$(KBUILD_CFLAGS))
cflags-$(CONFIG_ARM) := $(subst -pg,,$(KBUILD_CFLAGS)) \
-fno-builtin -fpic -mno-single-pic-base
-KBUILD_CFLAGS := $(cflags-y) \
+cflags-$(CONFIG_EFI_ARMSTUB) += -I$(srctree)/scripts/dtc/libfdt
+
+KBUILD_CFLAGS := $(cflags-y) -DDISABLE_BRANCH_PROFILING \
$(call cc-option,-ffreestanding) \
$(call cc-option,-fno-stack-protector)
GCOV_PROFILE := n
KASAN_SANITIZE := n
+UBSAN_SANITIZE := n
+OBJECT_FILES_NON_STANDARD := y
+
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT := n
+
+lib-y := efi-stub-helper.o gop.o
+
+# include the stub's generic dependencies from lib/ when building for ARM/arm64
+arm-deps := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c sort.c
+
+$(obj)/lib-%.o: $(srctree)/lib/%.c FORCE
+ $(call if_changed_rule,cc_o_c)
-lib-y := efi-stub-helper.o
-lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o
+lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o \
+ $(patsubst %.c,lib-%.o,$(arm-deps))
-CFLAGS_fdt.o += -I$(srctree)/scripts/dtc/libfdt/
+lib-$(CONFIG_ARM) += arm32-stub.o
+lib-$(CONFIG_ARM64) += arm64-stub.o random.o
+CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
#
# arm64 puts the stub in the kernel proper, which will unnecessarily retain all
@@ -32,10 +49,35 @@ CFLAGS_fdt.o += -I$(srctree)/scripts/dtc/libfdt/
# So let's apply the __init annotations at the section level, by prefixing
# the section names directly. This will ensure that even all the inline string
# literals are covered.
+# The fact that the stub and the kernel proper are essentially the same binary
+# also means that we need to be extra careful to make sure that the stub does
+# not rely on any absolute symbol references, considering that the virtual
+# kernel mapping that the linker uses is not active yet when the stub is
+# executing. So build all C dependencies of the EFI stub into libstub, and do
+# a verification pass to see if any absolute relocations exist in any of the
+# object files.
#
-extra-$(CONFIG_ARM64) := $(lib-y)
-lib-$(CONFIG_ARM64) := $(patsubst %.o,%.init.o,$(lib-y))
+extra-$(CONFIG_EFI_ARMSTUB) := $(lib-y)
+lib-$(CONFIG_EFI_ARMSTUB) := $(patsubst %.o,%.stub.o,$(lib-y))
-OBJCOPYFLAGS := --prefix-alloc-sections=.init
-$(obj)/%.init.o: $(obj)/%.o FORCE
- $(call if_changed,objcopy)
+STUBCOPY_FLAGS-y := -R .debug* -R *ksymtab* -R *kcrctab*
+STUBCOPY_FLAGS-$(CONFIG_ARM64) += --prefix-alloc-sections=.init \
+ --prefix-symbols=__efistub_
+STUBCOPY_RELOC-$(CONFIG_ARM64) := R_AARCH64_ABS
+
+$(obj)/%.stub.o: $(obj)/%.o FORCE
+ $(call if_changed,stubcopy)
+
+quiet_cmd_stubcopy = STUBCPY $@
+ cmd_stubcopy = if $(OBJCOPY) $(STUBCOPY_FLAGS-y) $< $@; then \
+ $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y) \
+ && (echo >&2 "$@: absolute symbol references not allowed in the EFI stub"; \
+ rm -f $@; /bin/false); else /bin/false; fi
+
+#
+# ARM discards the .data section because it disallows r/w data in the
+# decompressor. So move our .data to .data.efistub, which is preserved
+# explicitly by the decompressor linker script.
+#
+STUBCOPY_FLAGS-$(CONFIG_ARM) += --rename-section .data=.data.efistub
+STUBCOPY_RELOC-$(CONFIG_ARM) := R_ARM_ABS
diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index e29560e6b..993aa5675 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -13,31 +13,56 @@
*/
#include <linux/efi.h>
+#include <linux/sort.h>
#include <asm/efi.h>
#include "efistub.h"
-static int efi_secureboot_enabled(efi_system_table_t *sys_table_arg)
+bool __nokaslr;
+
+static int efi_get_secureboot(efi_system_table_t *sys_table_arg)
{
- static efi_guid_t const var_guid = EFI_GLOBAL_VARIABLE_GUID;
- static efi_char16_t const var_name[] = {
+ static efi_char16_t const sb_var_name[] = {
'S', 'e', 'c', 'u', 'r', 'e', 'B', 'o', 'o', 't', 0 };
+ static efi_char16_t const sm_var_name[] = {
+ 'S', 'e', 't', 'u', 'p', 'M', 'o', 'd', 'e', 0 };
+ efi_guid_t var_guid = EFI_GLOBAL_VARIABLE_GUID;
efi_get_variable_t *f_getvar = sys_table_arg->runtime->get_variable;
- unsigned long size = sizeof(u8);
- efi_status_t status;
u8 val;
+ unsigned long size = sizeof(val);
+ efi_status_t status;
+
+ status = f_getvar((efi_char16_t *)sb_var_name, (efi_guid_t *)&var_guid,
+ NULL, &size, &val);
- status = f_getvar((efi_char16_t *)var_name, (efi_guid_t *)&var_guid,
+ if (status != EFI_SUCCESS)
+ goto out_efi_err;
+
+ if (val == 0)
+ return 0;
+
+ status = f_getvar((efi_char16_t *)sm_var_name, (efi_guid_t *)&var_guid,
NULL, &size, &val);
+ if (status != EFI_SUCCESS)
+ goto out_efi_err;
+
+ if (val == 1)
+ return 0;
+
+ return 1;
+
+out_efi_err:
switch (status) {
- case EFI_SUCCESS:
- return val;
case EFI_NOT_FOUND:
return 0;
+ case EFI_DEVICE_ERROR:
+ return -EIO;
+ case EFI_SECURITY_VIOLATION:
+ return -EACCES;
default:
- return 1;
+ return -EINVAL;
}
}
@@ -144,6 +169,25 @@ void efi_char16_printk(efi_system_table_t *sys_table_arg,
out->output_string(out, str);
}
+static struct screen_info *setup_graphics(efi_system_table_t *sys_table_arg)
+{
+ efi_guid_t gop_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+ efi_status_t status;
+ unsigned long size;
+ void **gop_handle = NULL;
+ struct screen_info *si = NULL;
+
+ size = 0;
+ status = efi_call_early(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+ &gop_proto, NULL, &size, gop_handle);
+ if (status == EFI_BUFFER_TOO_SMALL) {
+ si = alloc_screen_info(sys_table_arg);
+ if (!si)
+ return NULL;
+ efi_setup_gop(sys_table_arg, si, &gop_proto, size);
+ }
+ return si;
+}
/*
* This function handles the architcture specific differences between arm and
@@ -182,6 +226,8 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
unsigned long reserve_addr = 0;
unsigned long reserve_size = 0;
+ int secure_boot = 0;
+ struct screen_info *si;
/* Check if we were booted by the EFI firmware */
if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
@@ -189,6 +235,10 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
pr_efi(sys_table, "Booting Linux Kernel...\n");
+ status = check_platform_features(sys_table);
+ if (status != EFI_SUCCESS)
+ goto fail;
+
/*
* Get a handle to the loaded image protocol. This is used to get
* information about the running image, such as size and the command
@@ -206,14 +256,6 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
pr_efi_err(sys_table, "Failed to find DRAM base\n");
goto fail;
}
- status = handle_kernel_image(sys_table, image_addr, &image_size,
- &reserve_addr,
- &reserve_size,
- dram_base, image);
- if (status != EFI_SUCCESS) {
- pr_efi_err(sys_table, "Failed to relocate kernel\n");
- goto fail;
- }
/*
* Get the command line from EFI, using the LOADED_IMAGE
@@ -223,19 +265,51 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
cmdline_ptr = efi_convert_cmdline(sys_table, image, &cmdline_size);
if (!cmdline_ptr) {
pr_efi_err(sys_table, "getting command line via LOADED_IMAGE_PROTOCOL\n");
- goto fail_free_image;
+ goto fail;
+ }
+
+ /* check whether 'nokaslr' was passed on the command line */
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+ static const u8 default_cmdline[] = CONFIG_CMDLINE;
+ const u8 *str, *cmdline = cmdline_ptr;
+
+ if (IS_ENABLED(CONFIG_CMDLINE_FORCE))
+ cmdline = default_cmdline;
+ str = strstr(cmdline, "nokaslr");
+ if (str == cmdline || (str > cmdline && *(str - 1) == ' '))
+ __nokaslr = true;
+ }
+
+ si = setup_graphics(sys_table);
+
+ status = handle_kernel_image(sys_table, image_addr, &image_size,
+ &reserve_addr,
+ &reserve_size,
+ dram_base, image);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Failed to relocate kernel\n");
+ goto fail_free_cmdline;
}
status = efi_parse_options(cmdline_ptr);
if (status != EFI_SUCCESS)
pr_efi_err(sys_table, "Failed to parse EFI cmdline options\n");
+ secure_boot = efi_get_secureboot(sys_table);
+ if (secure_boot > 0)
+ pr_efi(sys_table, "UEFI Secure Boot is enabled.\n");
+
+ if (secure_boot < 0) {
+ pr_efi_err(sys_table,
+ "could not determine UEFI Secure Boot status.\n");
+ }
+
/*
* Unauthenticated device tree data is a security hazard, so
* ignore 'dtb=' unless UEFI Secure Boot is disabled.
*/
- if (efi_secureboot_enabled(sys_table)) {
- pr_efi(sys_table, "UEFI Secure Boot is enabled.\n");
+ if (secure_boot != 0 && strstr(cmdline_ptr, "dtb=")) {
+ pr_efi(sys_table, "Ignoring DTB from command line.\n");
} else {
status = handle_cmdline_files(sys_table, image, cmdline_ptr,
"dtb=",
@@ -243,7 +317,7 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
if (status != EFI_SUCCESS) {
pr_efi_err(sys_table, "Failed to load device tree!\n");
- goto fail_free_cmdline;
+ goto fail_free_image;
}
}
@@ -285,12 +359,12 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
efi_free(sys_table, initrd_size, initrd_addr);
efi_free(sys_table, fdt_size, fdt_addr);
-fail_free_cmdline:
- efi_free(sys_table, cmdline_size, (unsigned long)cmdline_ptr);
-
fail_free_image:
efi_free(sys_table, image_size, *image_addr);
efi_free(sys_table, reserve_size, reserve_addr);
+fail_free_cmdline:
+ free_screen_info(sys_table, si);
+ efi_free(sys_table, cmdline_size, (unsigned long)cmdline_ptr);
fail:
return EFI_ERROR;
}
@@ -302,8 +376,48 @@ fail:
* The value chosen is the largest non-zero power of 2 suitable for this purpose
* both on 32-bit and 64-bit ARM CPUs, to maximize the likelihood that it can
* be mapped efficiently.
+ * Since 32-bit ARM could potentially execute with a 1G/3G user/kernel split,
+ * map everything below 1 GB.
+ */
+#define EFI_RT_VIRTUAL_BASE SZ_512M
+
+static int cmp_mem_desc(const void *l, const void *r)
+{
+ const efi_memory_desc_t *left = l, *right = r;
+
+ return (left->phys_addr > right->phys_addr) ? 1 : -1;
+}
+
+/*
+ * Returns whether region @left ends exactly where region @right starts,
+ * or false if either argument is NULL.
+ */
+static bool regions_are_adjacent(efi_memory_desc_t *left,
+ efi_memory_desc_t *right)
+{
+ u64 left_end;
+
+ if (left == NULL || right == NULL)
+ return false;
+
+ left_end = left->phys_addr + left->num_pages * EFI_PAGE_SIZE;
+
+ return left_end == right->phys_addr;
+}
+
+/*
+ * Returns whether region @left and region @right have compatible memory type
+ * mapping attributes, and are both EFI_MEMORY_RUNTIME regions.
*/
-#define EFI_RT_VIRTUAL_BASE 0x40000000
+static bool regions_have_compatible_memory_type_attrs(efi_memory_desc_t *left,
+ efi_memory_desc_t *right)
+{
+ static const u64 mem_type_mask = EFI_MEMORY_WB | EFI_MEMORY_WT |
+ EFI_MEMORY_WC | EFI_MEMORY_UC |
+ EFI_MEMORY_RUNTIME;
+
+ return ((left->attribute ^ right->attribute) & mem_type_mask) == 0;
+}
/*
* efi_get_virtmap() - create a virtual mapping for the EFI memory map
@@ -317,33 +431,52 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
int *count)
{
u64 efi_virt_base = EFI_RT_VIRTUAL_BASE;
- efi_memory_desc_t *out = runtime_map;
+ efi_memory_desc_t *in, *prev = NULL, *out = runtime_map;
int l;
- for (l = 0; l < map_size; l += desc_size) {
- efi_memory_desc_t *in = (void *)memory_map + l;
+ /*
+ * To work around potential issues with the Properties Table feature
+ * introduced in UEFI 2.5, which may split PE/COFF executable images
+ * in memory into several RuntimeServicesCode and RuntimeServicesData
+ * regions, we need to preserve the relative offsets between adjacent
+ * EFI_MEMORY_RUNTIME regions with the same memory type attributes.
+ * The easiest way to find adjacent regions is to sort the memory map
+ * before traversing it.
+ */
+ sort(memory_map, map_size / desc_size, desc_size, cmp_mem_desc, NULL);
+
+ for (l = 0; l < map_size; l += desc_size, prev = in) {
u64 paddr, size;
+ in = (void *)memory_map + l;
if (!(in->attribute & EFI_MEMORY_RUNTIME))
continue;
+ paddr = in->phys_addr;
+ size = in->num_pages * EFI_PAGE_SIZE;
+
/*
* Make the mapping compatible with 64k pages: this allows
* a 4k page size kernel to kexec a 64k page size kernel and
* vice versa.
*/
- paddr = round_down(in->phys_addr, SZ_64K);
- size = round_up(in->num_pages * EFI_PAGE_SIZE +
- in->phys_addr - paddr, SZ_64K);
-
- /*
- * Avoid wasting memory on PTEs by choosing a virtual base that
- * is compatible with section mappings if this region has the
- * appropriate size and physical alignment. (Sections are 2 MB
- * on 4k granule kernels)
- */
- if (IS_ALIGNED(in->phys_addr, SZ_2M) && size >= SZ_2M)
- efi_virt_base = round_up(efi_virt_base, SZ_2M);
+ if (!regions_are_adjacent(prev, in) ||
+ !regions_have_compatible_memory_type_attrs(prev, in)) {
+
+ paddr = round_down(in->phys_addr, SZ_64K);
+ size += in->phys_addr - paddr;
+
+ /*
+ * Avoid wasting memory on PTEs by choosing a virtual
+ * base that is compatible with section mappings if this
+ * region has the appropriate size and physical
+ * alignment. (Sections are 2 MB on 4k granule kernels)
+ */
+ if (IS_ALIGNED(in->phys_addr, SZ_2M) && size >= SZ_2M)
+ efi_virt_base = round_up(efi_virt_base, SZ_2M);
+ else
+ efi_virt_base = round_up(efi_virt_base, SZ_64K);
+ }
in->virt_addr = efi_virt_base + in->phys_addr - paddr;
efi_virt_base += size;
diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
new file mode 100644
index 000000000..e1f0b28e1
--- /dev/null
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2013 Linaro Ltd; <roy.franz@linaro.org>
+ *
+ * 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 <asm/efi.h>
+
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+ int block;
+
+ /* non-LPAE kernels can run anywhere */
+ if (!IS_ENABLED(CONFIG_ARM_LPAE))
+ return EFI_SUCCESS;
+
+ /* LPAE kernels need compatible hardware */
+ block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
+ if (block < 5) {
+ pr_efi_err(sys_table_arg, "This LPAE kernel is not supported by your CPU\n");
+ return EFI_UNSUPPORTED;
+ }
+ return EFI_SUCCESS;
+}
+
+static efi_guid_t screen_info_guid = LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID;
+
+struct screen_info *alloc_screen_info(efi_system_table_t *sys_table_arg)
+{
+ struct screen_info *si;
+ efi_status_t status;
+
+ /*
+ * Unlike on arm64, where we can directly fill out the screen_info
+ * structure from the stub, we need to allocate a buffer to hold
+ * its contents while we hand over to the kernel proper from the
+ * decompressor.
+ */
+ status = efi_call_early(allocate_pool, EFI_RUNTIME_SERVICES_DATA,
+ sizeof(*si), (void **)&si);
+
+ if (status != EFI_SUCCESS)
+ return NULL;
+
+ status = efi_call_early(install_configuration_table,
+ &screen_info_guid, si);
+ if (status == EFI_SUCCESS)
+ return si;
+
+ efi_call_early(free_pool, si);
+ return NULL;
+}
+
+void free_screen_info(efi_system_table_t *sys_table_arg, struct screen_info *si)
+{
+ if (!si)
+ return;
+
+ efi_call_early(install_configuration_table, &screen_info_guid, NULL);
+ efi_call_early(free_pool, si);
+}
+
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
+ unsigned long *image_addr,
+ unsigned long *image_size,
+ unsigned long *reserve_addr,
+ unsigned long *reserve_size,
+ unsigned long dram_base,
+ efi_loaded_image_t *image)
+{
+ unsigned long nr_pages;
+ efi_status_t status;
+ /* Use alloc_addr to tranlsate between types */
+ efi_physical_addr_t alloc_addr;
+
+ /*
+ * Verify that the DRAM base address is compatible with the ARM
+ * boot protocol, which determines the base of DRAM by masking
+ * off the low 27 bits of the address at which the zImage is
+ * loaded. These assumptions are made by the decompressor,
+ * before any memory map is available.
+ */
+ dram_base = round_up(dram_base, SZ_128M);
+
+ /*
+ * Reserve memory for the uncompressed kernel image. This is
+ * all that prevents any future allocations from conflicting
+ * with the kernel. Since we can't tell from the compressed
+ * image how much DRAM the kernel actually uses (due to BSS
+ * size uncertainty) we allocate the maximum possible size.
+ * Do this very early, as prints can cause memory allocations
+ * that may conflict with this.
+ */
+ alloc_addr = dram_base;
+ *reserve_size = MAX_UNCOMP_KERNEL_SIZE;
+ nr_pages = round_up(*reserve_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+ status = sys_table->boottime->allocate_pages(EFI_ALLOCATE_ADDRESS,
+ EFI_LOADER_DATA,
+ nr_pages, &alloc_addr);
+ if (status != EFI_SUCCESS) {
+ *reserve_size = 0;
+ pr_efi_err(sys_table, "Unable to allocate memory for uncompressed kernel.\n");
+ return status;
+ }
+ *reserve_addr = alloc_addr;
+
+ /*
+ * Relocate the zImage, so that it appears in the lowest 128 MB
+ * memory window.
+ */
+ *image_size = image->image_size;
+ status = efi_relocate_kernel(sys_table, image_addr, *image_size,
+ *image_size,
+ dram_base + MAX_UNCOMP_KERNEL_SIZE, 0);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Failed to relocate kernel.\n");
+ efi_free(sys_table, *reserve_size, *reserve_addr);
+ *reserve_size = 0;
+ return status;
+ }
+
+ /*
+ * Check to see if we were able to allocate memory low enough
+ * in memory. The kernel determines the base of DRAM from the
+ * address at which the zImage is loaded.
+ */
+ if (*image_addr + *image_size > dram_base + ZIMAGE_OFFSET_LIMIT) {
+ pr_efi_err(sys_table, "Failed to relocate kernel, no low memory available.\n");
+ efi_free(sys_table, *reserve_size, *reserve_addr);
+ *reserve_size = 0;
+ efi_free(sys_table, *image_size, *image_addr);
+ *image_size = 0;
+ return EFI_LOAD_ERROR;
+ }
+ return EFI_SUCCESS;
+}
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
new file mode 100644
index 000000000..eae693eb3
--- /dev/null
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2013, 2014 Linaro Ltd; <roy.franz@linaro.org>
+ *
+ * This file implements the EFI boot stub for the arm64 kernel.
+ * Adapted from ARM version by Mark Salter <msalter@redhat.com>
+ *
+ * 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 <asm/efi.h>
+#include <asm/sections.h>
+#include <asm/sysreg.h>
+
+#include "efistub.h"
+
+extern bool __nokaslr;
+
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+ u64 tg;
+
+ /* UEFI mandates support for 4 KB granularity, no need to check */
+ if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
+ return EFI_SUCCESS;
+
+ tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_TGRAN_SHIFT) & 0xf;
+ if (tg != ID_AA64MMFR0_TGRAN_SUPPORTED) {
+ if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
+ pr_efi_err(sys_table_arg, "This 64 KB granular kernel is not supported by your CPU\n");
+ else
+ pr_efi_err(sys_table_arg, "This 16 KB granular kernel is not supported by your CPU\n");
+ return EFI_UNSUPPORTED;
+ }
+ return EFI_SUCCESS;
+}
+
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
+ unsigned long *image_addr,
+ unsigned long *image_size,
+ unsigned long *reserve_addr,
+ unsigned long *reserve_size,
+ unsigned long dram_base,
+ efi_loaded_image_t *image)
+{
+ efi_status_t status;
+ unsigned long kernel_size, kernel_memsize = 0;
+ void *old_image_addr = (void *)*image_addr;
+ unsigned long preferred_offset;
+ u64 phys_seed = 0;
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+ if (!__nokaslr) {
+ status = efi_get_random_bytes(sys_table_arg,
+ sizeof(phys_seed),
+ (u8 *)&phys_seed);
+ if (status == EFI_NOT_FOUND) {
+ pr_efi(sys_table_arg, "EFI_RNG_PROTOCOL unavailable, no randomness supplied\n");
+ } else if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table_arg, "efi_get_random_bytes() failed\n");
+ return status;
+ }
+ } else {
+ pr_efi(sys_table_arg, "KASLR disabled on kernel command line\n");
+ }
+ }
+
+ /*
+ * The preferred offset of the kernel Image is TEXT_OFFSET bytes beyond
+ * a 2 MB aligned base, which itself may be lower than dram_base, as
+ * long as the resulting offset equals or exceeds it.
+ */
+ preferred_offset = round_down(dram_base, MIN_KIMG_ALIGN) + TEXT_OFFSET;
+ if (preferred_offset < dram_base)
+ preferred_offset += MIN_KIMG_ALIGN;
+
+ kernel_size = _edata - _text;
+ kernel_memsize = kernel_size + (_end - _edata);
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && phys_seed != 0) {
+ /*
+ * If CONFIG_DEBUG_ALIGN_RODATA is not set, produce a
+ * displacement in the interval [0, MIN_KIMG_ALIGN) that
+ * is a multiple of the minimal segment alignment (SZ_64K)
+ */
+ u32 mask = (MIN_KIMG_ALIGN - 1) & ~(SZ_64K - 1);
+ u32 offset = !IS_ENABLED(CONFIG_DEBUG_ALIGN_RODATA) ?
+ (phys_seed >> 32) & mask : TEXT_OFFSET;
+
+ /*
+ * If KASLR is enabled, and we have some randomness available,
+ * locate the kernel at a randomized offset in physical memory.
+ */
+ *reserve_size = kernel_memsize + offset;
+ status = efi_random_alloc(sys_table_arg, *reserve_size,
+ MIN_KIMG_ALIGN, reserve_addr,
+ (u32)phys_seed);
+
+ *image_addr = *reserve_addr + offset;
+ } else {
+ /*
+ * Else, try a straight allocation at the preferred offset.
+ * This will work around the issue where, if dram_base == 0x0,
+ * efi_low_alloc() refuses to allocate at 0x0 (to prevent the
+ * address of the allocation to be mistaken for a FAIL return
+ * value or a NULL pointer). It will also ensure that, on
+ * platforms where the [dram_base, dram_base + TEXT_OFFSET)
+ * interval is partially occupied by the firmware (like on APM
+ * Mustang), we can still place the kernel at the address
+ * 'dram_base + TEXT_OFFSET'.
+ */
+ if (*image_addr == preferred_offset)
+ return EFI_SUCCESS;
+
+ *image_addr = *reserve_addr = preferred_offset;
+ *reserve_size = round_up(kernel_memsize, EFI_ALLOC_ALIGN);
+
+ status = efi_call_early(allocate_pages, EFI_ALLOCATE_ADDRESS,
+ EFI_LOADER_DATA,
+ *reserve_size / EFI_PAGE_SIZE,
+ (efi_physical_addr_t *)reserve_addr);
+ }
+
+ if (status != EFI_SUCCESS) {
+ *reserve_size = kernel_memsize + TEXT_OFFSET;
+ status = efi_low_alloc(sys_table_arg, *reserve_size,
+ MIN_KIMG_ALIGN, reserve_addr);
+
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table_arg, "Failed to relocate kernel\n");
+ *reserve_size = 0;
+ return status;
+ }
+ *image_addr = *reserve_addr + TEXT_OFFSET;
+ }
+ memcpy((void *)*image_addr, old_image_addr, kernel_size);
+
+ return EFI_SUCCESS;
+}
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index f07d4a67f..aded10662 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -41,6 +41,8 @@ static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE;
#define EFI_ALLOC_ALIGN EFI_PAGE_SIZE
#endif
+#define EFI_MMAP_NR_SLACK_SLOTS 8
+
struct file_info {
efi_file_handle_t *handle;
u64 size;
@@ -63,49 +65,62 @@ void efi_printk(efi_system_table_t *sys_table_arg, char *str)
}
}
+static inline bool mmap_has_headroom(unsigned long buff_size,
+ unsigned long map_size,
+ unsigned long desc_size)
+{
+ unsigned long slack = buff_size - map_size;
+
+ return slack / desc_size >= EFI_MMAP_NR_SLACK_SLOTS;
+}
+
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)
+ struct efi_boot_memmap *map)
{
efi_memory_desc_t *m = NULL;
efi_status_t status;
unsigned long key;
u32 desc_version;
- *map_size = sizeof(*m) * 32;
+ *map->desc_size = sizeof(*m);
+ *map->map_size = *map->desc_size * 32;
+ *map->buff_size = *map->map_size;
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_early(allocate_pool, EFI_LOADER_DATA,
- *map_size, (void **)&m);
+ *map->map_size, (void **)&m);
if (status != EFI_SUCCESS)
goto fail;
- *desc_size = 0;
+ *map->desc_size = 0;
key = 0;
- status = efi_call_early(get_memory_map, map_size, m,
- &key, desc_size, &desc_version);
- if (status == EFI_BUFFER_TOO_SMALL) {
+ status = efi_call_early(get_memory_map, map->map_size, m,
+ &key, map->desc_size, &desc_version);
+ if (status == EFI_BUFFER_TOO_SMALL ||
+ !mmap_has_headroom(*map->buff_size, *map->map_size,
+ *map->desc_size)) {
efi_call_early(free_pool, m);
+ /*
+ * Make sure there is some entries of headroom so that the
+ * buffer can be reused for a new map after allocations are
+ * no longer permitted. Its unlikely that the map will grow to
+ * exceed this headroom once we are ready to trigger
+ * ExitBootServices()
+ */
+ *map->map_size += *map->desc_size * EFI_MMAP_NR_SLACK_SLOTS;
+ *map->buff_size = *map->map_size;
goto again;
}
if (status != EFI_SUCCESS)
efi_call_early(free_pool, m);
- if (key_ptr && status == EFI_SUCCESS)
- *key_ptr = key;
- if (desc_ver && status == EFI_SUCCESS)
- *desc_ver = desc_version;
+ if (map->key_ptr && status == EFI_SUCCESS)
+ *map->key_ptr = key;
+ if (map->desc_ver && status == EFI_SUCCESS)
+ *map->desc_ver = desc_version;
fail:
- *map = m;
+ *map->map = m;
return status;
}
@@ -113,22 +128,31 @@ fail:
unsigned long get_dram_base(efi_system_table_t *sys_table_arg)
{
efi_status_t status;
- unsigned long map_size;
+ unsigned long map_size, buff_size;
unsigned long membase = EFI_ERROR;
struct efi_memory_map map;
efi_memory_desc_t *md;
+ struct efi_boot_memmap boot_map;
- status = efi_get_memory_map(sys_table_arg, (efi_memory_desc_t **)&map.map,
- &map_size, &map.desc_size, NULL, NULL);
+ boot_map.map = (efi_memory_desc_t **)&map.map;
+ boot_map.map_size = &map_size;
+ boot_map.desc_size = &map.desc_size;
+ boot_map.desc_ver = NULL;
+ boot_map.key_ptr = NULL;
+ boot_map.buff_size = &buff_size;
+
+ status = efi_get_memory_map(sys_table_arg, &boot_map);
if (status != EFI_SUCCESS)
return membase;
map.map_end = map.map + map_size;
- for_each_efi_memory_desc(&map, md)
- if (md->attribute & EFI_MEMORY_WB)
+ for_each_efi_memory_desc_in_map(&map, md) {
+ if (md->attribute & EFI_MEMORY_WB) {
if (membase > md->phys_addr)
membase = md->phys_addr;
+ }
+ }
efi_call_early(free_pool, map.map);
@@ -142,15 +166,22 @@ 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;
+ unsigned long map_size, desc_size, buff_size;
efi_memory_desc_t *map;
efi_status_t status;
unsigned long nr_pages;
u64 max_addr = 0;
int i;
+ struct efi_boot_memmap boot_map;
- status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
- NULL, NULL);
+ boot_map.map = &map;
+ boot_map.map_size = &map_size;
+ boot_map.desc_size = &desc_size;
+ boot_map.desc_ver = NULL;
+ boot_map.key_ptr = NULL;
+ boot_map.buff_size = &buff_size;
+
+ status = efi_get_memory_map(sys_table_arg, &boot_map);
if (status != EFI_SUCCESS)
goto fail;
@@ -228,14 +259,21 @@ 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;
+ unsigned long map_size, desc_size, buff_size;
efi_memory_desc_t *map;
efi_status_t status;
unsigned long nr_pages;
int i;
+ struct efi_boot_memmap boot_map;
+
+ boot_map.map = &map;
+ boot_map.map_size = &map_size;
+ boot_map.desc_size = &desc_size;
+ boot_map.desc_ver = NULL;
+ boot_map.key_ptr = NULL;
+ boot_map.buff_size = &buff_size;
- status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
- NULL, NULL);
+ status = efi_get_memory_map(sys_table_arg, &boot_map);
if (status != EFI_SUCCESS)
goto fail;
@@ -649,6 +687,10 @@ static u8 *efi_utf16_to_utf8(u8 *dst, const u16 *src, int n)
return dst;
}
+#ifndef MAX_CMDLINE_ADDRESS
+#define MAX_CMDLINE_ADDRESS ULONG_MAX
+#endif
+
/*
* Convert the unicode UEFI command line to ASCII to pass to kernel.
* Size of memory allocated return in *cmd_line_len.
@@ -684,7 +726,8 @@ char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
options_bytes++; /* NUL termination */
- status = efi_low_alloc(sys_table_arg, options_bytes, 0, &cmdline_addr);
+ status = efi_high_alloc(sys_table_arg, options_bytes, 0,
+ &cmdline_addr, MAX_CMDLINE_ADDRESS);
if (status != EFI_SUCCESS)
return NULL;
@@ -697,3 +740,76 @@ char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
*cmd_line_len = options_bytes;
return (char *)cmdline_addr;
}
+
+/*
+ * Handle calling ExitBootServices according to the requirements set out by the
+ * spec. Obtains the current memory map, and returns that info after calling
+ * ExitBootServices. The client must specify a function to perform any
+ * processing of the memory map data prior to ExitBootServices. A client
+ * specific structure may be passed to the function via priv. The client
+ * function may be called multiple times.
+ */
+efi_status_t efi_exit_boot_services(efi_system_table_t *sys_table_arg,
+ void *handle,
+ struct efi_boot_memmap *map,
+ void *priv,
+ efi_exit_boot_map_processing priv_func)
+{
+ efi_status_t status;
+
+ status = efi_get_memory_map(sys_table_arg, map);
+
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ status = priv_func(sys_table_arg, map, priv);
+ if (status != EFI_SUCCESS)
+ goto free_map;
+
+ status = efi_call_early(exit_boot_services, handle, *map->key_ptr);
+
+ if (status == EFI_INVALID_PARAMETER) {
+ /*
+ * The memory map changed between efi_get_memory_map() and
+ * exit_boot_services(). Per the UEFI Spec v2.6, Section 6.4:
+ * EFI_BOOT_SERVICES.ExitBootServices we need to get the
+ * updated map, and try again. The spec implies one retry
+ * should be sufficent, which is confirmed against the EDK2
+ * implementation. Per the spec, we can only invoke
+ * get_memory_map() and exit_boot_services() - we cannot alloc
+ * so efi_get_memory_map() cannot be used, and we must reuse
+ * the buffer. For all practical purposes, the headroom in the
+ * buffer should account for any changes in the map so the call
+ * to get_memory_map() is expected to succeed here.
+ */
+ *map->map_size = *map->buff_size;
+ status = efi_call_early(get_memory_map,
+ map->map_size,
+ *map->map,
+ map->key_ptr,
+ map->desc_size,
+ map->desc_ver);
+
+ /* exit_boot_services() was called, thus cannot free */
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ status = priv_func(sys_table_arg, map, priv);
+ /* exit_boot_services() was called, thus cannot free */
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ status = efi_call_early(exit_boot_services, handle, *map->key_ptr);
+ }
+
+ /* exit_boot_services() was called, thus cannot free */
+ if (status != EFI_SUCCESS)
+ goto fail;
+
+ return EFI_SUCCESS;
+
+free_map:
+ efi_call_early(free_pool, *map->map);
+fail:
+ return status;
+}
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index e334a01cf..ee49cd23e 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -5,9 +5,15 @@
/* error code which can't be mistaken for valid address */
#define EFI_ERROR (~0UL)
-#undef memcpy
-#undef memset
-#undef memmove
+/*
+ * __init annotations should not be used in the EFI stub, since the code is
+ * either included in the decompressor (x86, ARM) where they have no effect,
+ * or the whole stub is __init annotated at the section level (arm64), by
+ * renaming the sections, in which case the __init annotation will be
+ * redundant, and will result in section names like .init.init.text, and our
+ * linker script does not expect that.
+ */
+#undef __init
void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
@@ -47,4 +53,13 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
unsigned long desc_size, efi_memory_desc_t *runtime_map,
int *count);
+efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table,
+ unsigned long size, u8 *out);
+
+efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,
+ unsigned long size, unsigned long align,
+ unsigned long *addr, unsigned long random_seed);
+
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg);
+
#endif
diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index ef5d764e2..a6a93116a 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -24,7 +24,7 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
unsigned long map_size, unsigned long desc_size,
u32 desc_ver)
{
- int node, prev, num_rsv;
+ int node, num_rsv;
int status;
u32 fdt_val32;
u64 fdt_val64;
@@ -54,28 +54,6 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
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;
- 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;
- }
-
- /*
* Delete all memory reserve map entries. When booting via UEFI,
* kernel will use the UEFI memory map to find reserved regions.
*/
@@ -147,15 +125,20 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
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;
-
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+ efi_status_t efi_status;
+
+ efi_status = efi_get_random_bytes(sys_table, sizeof(fdt_val64),
+ (u8 *)&fdt_val64);
+ if (efi_status == EFI_SUCCESS) {
+ status = fdt_setprop(fdt, node, "kaslr-seed",
+ &fdt_val64, sizeof(fdt_val64));
+ if (status)
+ goto fdt_set_fail;
+ } else if (efi_status != EFI_NOT_FOUND) {
+ return efi_status;
+ }
+ }
return EFI_SUCCESS;
fdt_set_fail:
@@ -169,6 +152,27 @@ fdt_set_fail:
#define EFI_FDT_ALIGN EFI_PAGE_SIZE
#endif
+struct exit_boot_struct {
+ efi_memory_desc_t *runtime_map;
+ int *runtime_entry_count;
+};
+
+static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg,
+ struct efi_boot_memmap *map,
+ void *priv)
+{
+ struct exit_boot_struct *p = priv;
+ /*
+ * Update the memory map with virtual addresses. The function will also
+ * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
+ * entries so that we can pass it straight to SetVirtualAddressMap()
+ */
+ efi_get_virtmap(*map->map, *map->map_size, *map->desc_size,
+ p->runtime_map, p->runtime_entry_count);
+
+ return EFI_SUCCESS;
+}
+
/*
* Allocate memory for a new FDT, then add EFI, commandline, and
* initrd related fields to the FDT. This routine increases the
@@ -192,13 +196,22 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
unsigned long fdt_addr,
unsigned long fdt_size)
{
- unsigned long map_size, desc_size;
+ unsigned long map_size, desc_size, buff_size;
u32 desc_ver;
unsigned long mmap_key;
efi_memory_desc_t *memory_map, *runtime_map;
unsigned long new_fdt_size;
efi_status_t status;
int runtime_entry_count = 0;
+ struct efi_boot_memmap map;
+ struct exit_boot_struct priv;
+
+ map.map = &runtime_map;
+ map.map_size = &map_size;
+ map.desc_size = &desc_size;
+ map.desc_ver = &desc_ver;
+ map.key_ptr = &mmap_key;
+ map.buff_size = &buff_size;
/*
* Get a copy of the current memory map that we will use to prepare
@@ -206,8 +219,7 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
* subsequent allocations adding entries, since they could not affect
* the number of EFI_MEMORY_RUNTIME regions.
*/
- status = efi_get_memory_map(sys_table, &runtime_map, &map_size,
- &desc_size, &desc_ver, &mmap_key);
+ status = efi_get_memory_map(sys_table, &map);
if (status != EFI_SUCCESS) {
pr_efi_err(sys_table, "Unable to retrieve UEFI memory map.\n");
return status;
@@ -216,6 +228,7 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
pr_efi(sys_table,
"Exiting boot services and installing virtual address map...\n");
+ map.map = &memory_map;
/*
* Estimate size of new FDT, and allocate memory for it. We
* will allocate a bigger buffer if this ends up being too
@@ -235,8 +248,7 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
* 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);
+ status = efi_get_memory_map(sys_table, &map);
if (status != EFI_SUCCESS)
goto fail_free_new_fdt;
@@ -262,21 +274,16 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
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");
+ pr_efi_err(sys_table, "Unable to construct new device tree.\n");
goto fail_free_mmap;
}
}
- /*
- * Update the memory map with virtual addresses. The function will also
- * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
- * entries so that we can pass it straight into SetVirtualAddressMap()
- */
- efi_get_virtmap(memory_map, map_size, desc_size, runtime_map,
- &runtime_entry_count);
-
- /* Now we are ready to exit_boot_services.*/
- status = sys_table->boottime->exit_boot_services(handle, mmap_key);
+ sys_table->boottime->free_pool(memory_map);
+ priv.runtime_map = runtime_map;
+ priv.runtime_entry_count = &runtime_entry_count;
+ status = efi_exit_boot_services(sys_table, handle, &map, &priv,
+ exit_boot_func);
if (status == EFI_SUCCESS) {
efi_set_virtual_address_map_t *svam;
diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c
new file mode 100644
index 000000000..932742e4c
--- /dev/null
+++ b/drivers/firmware/efi/libstub/gop.c
@@ -0,0 +1,354 @@
+/* -----------------------------------------------------------------------
+ *
+ * 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 <linux/screen_info.h>
+#include <asm/efi.h>
+#include <asm/setup.h>
+
+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;
+}
+
+static void
+setup_pixel_info(struct screen_info *si, u32 pixels_per_scan_line,
+ struct efi_pixel_bitmask pixel_info, int pixel_format)
+{
+ 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;
+ }
+}
+
+static efi_status_t
+__gop_query32(efi_system_table_t *sys_table_arg,
+ struct efi_graphics_output_protocol_32 *gop32,
+ struct efi_graphics_output_mode_info **info,
+ unsigned long *size, u64 *fb_base)
+{
+ struct efi_graphics_output_protocol_mode_32 *mode;
+ efi_graphics_output_protocol_query_mode query_mode;
+ efi_status_t status;
+ unsigned long m;
+
+ m = gop32->mode;
+ mode = (struct efi_graphics_output_protocol_mode_32 *)m;
+ query_mode = (void *)(unsigned long)gop32->query_mode;
+
+ status = __efi_call_early(query_mode, (void *)gop32, mode->mode, size,
+ info);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ *fb_base = mode->frame_buffer_base;
+ return status;
+}
+
+static efi_status_t
+setup_gop32(efi_system_table_t *sys_table_arg, struct screen_info *si,
+ efi_guid_t *proto, unsigned long size, void **gop_handle)
+{
+ struct efi_graphics_output_protocol_32 *gop32, *first_gop;
+ unsigned long nr_gops;
+ u16 width, height;
+ u32 pixels_per_scan_line;
+ u32 ext_lfb_base;
+ u64 fb_base;
+ struct efi_pixel_bitmask pixel_info;
+ int pixel_format;
+ efi_status_t status = EFI_NOT_FOUND;
+ u32 *handles = (u32 *)(unsigned long)gop_handle;
+ int i;
+
+ first_gop = NULL;
+ gop32 = NULL;
+
+ nr_gops = size / sizeof(u32);
+ for (i = 0; i < nr_gops; i++) {
+ struct efi_graphics_output_mode_info *info = NULL;
+ efi_guid_t conout_proto = EFI_CONSOLE_OUT_DEVICE_GUID;
+ bool conout_found = false;
+ void *dummy = NULL;
+ efi_handle_t h = (efi_handle_t)(unsigned long)handles[i];
+ u64 current_fb_base;
+
+ status = efi_call_early(handle_protocol, h,
+ proto, (void **)&gop32);
+ if (status != EFI_SUCCESS)
+ continue;
+
+ status = efi_call_early(handle_protocol, h,
+ &conout_proto, &dummy);
+ if (status == EFI_SUCCESS)
+ conout_found = true;
+
+ status = __gop_query32(sys_table_arg, gop32, &info, &size,
+ &current_fb_base);
+ if (status == EFI_SUCCESS && (!first_gop || conout_found)) {
+ /*
+ * Systems that use the UEFI Console Splitter may
+ * provide multiple GOP devices, not all of which are
+ * backed by real hardware. The workaround is to search
+ * for a GOP implementing the ConOut protocol, and if
+ * one isn't found, to just fall back to the first GOP.
+ */
+ width = info->horizontal_resolution;
+ height = info->vertical_resolution;
+ pixel_format = info->pixel_format;
+ pixel_info = info->pixel_information;
+ pixels_per_scan_line = info->pixels_per_scan_line;
+ fb_base = current_fb_base;
+
+ /*
+ * Once we've found a GOP supporting ConOut,
+ * don't bother looking any further.
+ */
+ first_gop = gop32;
+ if (conout_found)
+ break;
+ }
+ }
+
+ /* Did we find any GOPs? */
+ if (!first_gop)
+ goto out;
+
+ /* EFI framebuffer */
+ si->orig_video_isVGA = VIDEO_TYPE_EFI;
+
+ si->lfb_width = width;
+ si->lfb_height = height;
+ si->lfb_base = fb_base;
+
+ ext_lfb_base = (u64)(unsigned long)fb_base >> 32;
+ if (ext_lfb_base) {
+ si->capabilities |= VIDEO_CAPABILITY_64BIT_BASE;
+ si->ext_lfb_base = ext_lfb_base;
+ }
+
+ si->pages = 1;
+
+ setup_pixel_info(si, pixels_per_scan_line, pixel_info, pixel_format);
+
+ si->lfb_size = si->lfb_linelength * si->lfb_height;
+
+ si->capabilities |= VIDEO_CAPABILITY_SKIP_QUIRKS;
+out:
+ return status;
+}
+
+static efi_status_t
+__gop_query64(efi_system_table_t *sys_table_arg,
+ struct efi_graphics_output_protocol_64 *gop64,
+ struct efi_graphics_output_mode_info **info,
+ unsigned long *size, u64 *fb_base)
+{
+ struct efi_graphics_output_protocol_mode_64 *mode;
+ efi_graphics_output_protocol_query_mode query_mode;
+ efi_status_t status;
+ unsigned long m;
+
+ m = gop64->mode;
+ mode = (struct efi_graphics_output_protocol_mode_64 *)m;
+ query_mode = (void *)(unsigned long)gop64->query_mode;
+
+ status = __efi_call_early(query_mode, (void *)gop64, mode->mode, size,
+ info);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ *fb_base = mode->frame_buffer_base;
+ return status;
+}
+
+static efi_status_t
+setup_gop64(efi_system_table_t *sys_table_arg, struct screen_info *si,
+ efi_guid_t *proto, unsigned long size, void **gop_handle)
+{
+ struct efi_graphics_output_protocol_64 *gop64, *first_gop;
+ unsigned long nr_gops;
+ u16 width, height;
+ u32 pixels_per_scan_line;
+ u32 ext_lfb_base;
+ u64 fb_base;
+ struct efi_pixel_bitmask pixel_info;
+ int pixel_format;
+ efi_status_t status = EFI_NOT_FOUND;
+ u64 *handles = (u64 *)(unsigned long)gop_handle;
+ int i;
+
+ first_gop = NULL;
+ gop64 = NULL;
+
+ nr_gops = size / sizeof(u64);
+ for (i = 0; i < nr_gops; i++) {
+ struct efi_graphics_output_mode_info *info = NULL;
+ efi_guid_t conout_proto = EFI_CONSOLE_OUT_DEVICE_GUID;
+ bool conout_found = false;
+ void *dummy = NULL;
+ efi_handle_t h = (efi_handle_t)(unsigned long)handles[i];
+ u64 current_fb_base;
+
+ status = efi_call_early(handle_protocol, h,
+ proto, (void **)&gop64);
+ if (status != EFI_SUCCESS)
+ continue;
+
+ status = efi_call_early(handle_protocol, h,
+ &conout_proto, &dummy);
+ if (status == EFI_SUCCESS)
+ conout_found = true;
+
+ status = __gop_query64(sys_table_arg, gop64, &info, &size,
+ &current_fb_base);
+ if (status == EFI_SUCCESS && (!first_gop || conout_found)) {
+ /*
+ * Systems that use the UEFI Console Splitter may
+ * provide multiple GOP devices, not all of which are
+ * backed by real hardware. The workaround is to search
+ * for a GOP implementing the ConOut protocol, and if
+ * one isn't found, to just fall back to the first GOP.
+ */
+ width = info->horizontal_resolution;
+ height = info->vertical_resolution;
+ pixel_format = info->pixel_format;
+ pixel_info = info->pixel_information;
+ pixels_per_scan_line = info->pixels_per_scan_line;
+ fb_base = current_fb_base;
+
+ /*
+ * Once we've found a GOP supporting ConOut,
+ * don't bother looking any further.
+ */
+ first_gop = gop64;
+ if (conout_found)
+ break;
+ }
+ }
+
+ /* Did we find any GOPs? */
+ if (!first_gop)
+ goto out;
+
+ /* EFI framebuffer */
+ si->orig_video_isVGA = VIDEO_TYPE_EFI;
+
+ si->lfb_width = width;
+ si->lfb_height = height;
+ si->lfb_base = fb_base;
+
+ ext_lfb_base = (u64)(unsigned long)fb_base >> 32;
+ if (ext_lfb_base) {
+ si->capabilities |= VIDEO_CAPABILITY_64BIT_BASE;
+ si->ext_lfb_base = ext_lfb_base;
+ }
+
+ si->pages = 1;
+
+ setup_pixel_info(si, pixels_per_scan_line, pixel_info, pixel_format);
+
+ si->lfb_size = si->lfb_linelength * si->lfb_height;
+
+ si->capabilities |= VIDEO_CAPABILITY_SKIP_QUIRKS;
+out:
+ return status;
+}
+
+/*
+ * See if we have Graphics Output Protocol
+ */
+efi_status_t efi_setup_gop(efi_system_table_t *sys_table_arg,
+ struct screen_info *si, efi_guid_t *proto,
+ unsigned long size)
+{
+ efi_status_t status;
+ void **gop_handle = NULL;
+
+ status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
+ size, (void **)&gop_handle);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ status = efi_call_early(locate_handle,
+ EFI_LOCATE_BY_PROTOCOL,
+ proto, NULL, &size, gop_handle);
+ if (status != EFI_SUCCESS)
+ goto free_handle;
+
+ if (efi_is_64bit()) {
+ status = setup_gop64(sys_table_arg, si, proto, size,
+ gop_handle);
+ } else {
+ status = setup_gop32(sys_table_arg, si, proto, size,
+ gop_handle);
+ }
+
+free_handle:
+ efi_call_early(free_pool, gop_handle);
+ return status;
+}
diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c
new file mode 100644
index 000000000..0c9f58c5b
--- /dev/null
+++ b/drivers/firmware/efi/libstub/random.c
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2016 Linaro Ltd; <ard.biesheuvel@linaro.org>
+ *
+ * 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 <asm/efi.h>
+
+#include "efistub.h"
+
+struct efi_rng_protocol {
+ efi_status_t (*get_info)(struct efi_rng_protocol *,
+ unsigned long *, efi_guid_t *);
+ efi_status_t (*get_rng)(struct efi_rng_protocol *,
+ efi_guid_t *, unsigned long, u8 *out);
+};
+
+efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table_arg,
+ unsigned long size, u8 *out)
+{
+ efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
+ efi_status_t status;
+ struct efi_rng_protocol *rng;
+
+ status = efi_call_early(locate_protocol, &rng_proto, NULL,
+ (void **)&rng);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ return rng->get_rng(rng, NULL, size, out);
+}
+
+/*
+ * Return the number of slots covered by this entry, i.e., the number of
+ * addresses it covers that are suitably aligned and supply enough room
+ * for the allocation.
+ */
+static unsigned long get_entry_num_slots(efi_memory_desc_t *md,
+ unsigned long size,
+ unsigned long align)
+{
+ u64 start, end;
+
+ if (md->type != EFI_CONVENTIONAL_MEMORY)
+ return 0;
+
+ start = round_up(md->phys_addr, align);
+ end = round_down(md->phys_addr + md->num_pages * EFI_PAGE_SIZE - size,
+ align);
+
+ if (start > end)
+ return 0;
+
+ return (end - start + 1) / align;
+}
+
+/*
+ * The UEFI memory descriptors have a virtual address field that is only used
+ * when installing the virtual mapping using SetVirtualAddressMap(). Since it
+ * is unused here, we can reuse it to keep track of each descriptor's slot
+ * count.
+ */
+#define MD_NUM_SLOTS(md) ((md)->virt_addr)
+
+efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,
+ unsigned long size,
+ unsigned long align,
+ unsigned long *addr,
+ unsigned long random_seed)
+{
+ unsigned long map_size, desc_size, total_slots = 0, target_slot;
+ unsigned long buff_size;
+ efi_status_t status;
+ efi_memory_desc_t *memory_map;
+ int map_offset;
+ struct efi_boot_memmap map;
+
+ map.map = &memory_map;
+ map.map_size = &map_size;
+ map.desc_size = &desc_size;
+ map.desc_ver = NULL;
+ map.key_ptr = NULL;
+ map.buff_size = &buff_size;
+
+ status = efi_get_memory_map(sys_table_arg, &map);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ if (align < EFI_ALLOC_ALIGN)
+ align = EFI_ALLOC_ALIGN;
+
+ /* count the suitable slots in each memory map entry */
+ for (map_offset = 0; map_offset < map_size; map_offset += desc_size) {
+ efi_memory_desc_t *md = (void *)memory_map + map_offset;
+ unsigned long slots;
+
+ slots = get_entry_num_slots(md, size, align);
+ MD_NUM_SLOTS(md) = slots;
+ total_slots += slots;
+ }
+
+ /* find a random number between 0 and total_slots */
+ target_slot = (total_slots * (u16)random_seed) >> 16;
+
+ /*
+ * target_slot is now a value in the range [0, total_slots), and so
+ * it corresponds with exactly one of the suitable slots we recorded
+ * when iterating over the memory map the first time around.
+ *
+ * So iterate over the memory map again, subtracting the number of
+ * slots of each entry at each iteration, until we have found the entry
+ * that covers our chosen slot. Use the residual value of target_slot
+ * to calculate the randomly chosen address, and allocate it directly
+ * using EFI_ALLOCATE_ADDRESS.
+ */
+ for (map_offset = 0; map_offset < map_size; map_offset += desc_size) {
+ efi_memory_desc_t *md = (void *)memory_map + map_offset;
+ efi_physical_addr_t target;
+ unsigned long pages;
+
+ if (target_slot >= MD_NUM_SLOTS(md)) {
+ target_slot -= MD_NUM_SLOTS(md);
+ continue;
+ }
+
+ target = round_up(md->phys_addr, align) + target_slot * align;
+ pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+
+ status = efi_call_early(allocate_pages, EFI_ALLOCATE_ADDRESS,
+ EFI_LOADER_DATA, pages, &target);
+ if (status == EFI_SUCCESS)
+ *addr = target;
+ break;
+ }
+
+ efi_call_early(free_pool, memory_map);
+
+ return status;
+}
diff --git a/drivers/firmware/efi/libstub/string.c b/drivers/firmware/efi/libstub/string.c
new file mode 100644
index 000000000..09d5a0894
--- /dev/null
+++ b/drivers/firmware/efi/libstub/string.c
@@ -0,0 +1,57 @@
+/*
+ * Taken from:
+ * linux/lib/string.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+
+#ifndef __HAVE_ARCH_STRSTR
+/**
+ * strstr - Find the first substring in a %NUL terminated string
+ * @s1: The string to be searched
+ * @s2: The string to search for
+ */
+char *strstr(const char *s1, const char *s2)
+{
+ size_t l1, l2;
+
+ l2 = strlen(s2);
+ if (!l2)
+ return (char *)s1;
+ l1 = strlen(s1);
+ while (l1 >= l2) {
+ l1--;
+ if (!memcmp(s1, s2, l2))
+ return (char *)s1;
+ s1++;
+ }
+ return NULL;
+}
+#endif
+
+#ifndef __HAVE_ARCH_STRNCMP
+/**
+ * strncmp - Compare two length-limited strings
+ * @cs: One string
+ * @ct: Another string
+ * @count: The maximum number of bytes to compare
+ */
+int strncmp(const char *cs, const char *ct, size_t count)
+{
+ unsigned char c1, c2;
+
+ while (count) {
+ c1 = *cs++;
+ c2 = *ct++;
+ if (c1 != c2)
+ return c1 < c2 ? -1 : 1;
+ if (!c1)
+ break;
+ count--;
+ }
+ return 0;
+}
+#endif