Implement support for launching U-Boot via an EFI stub app on ARM64.
This is more or less a straight port of the x86 implementation, but due to the highly x86/qemu specific nature of that implementation I decided to just split it out to its own file.
Unlike the x86 implementation, there is no debug UART here since ARM platforms don't have a standard UART interface. However it is usually possible to port over the debug uart implementation for you platform for bringup purposes.
Currently this implementation doesn't provide a DTB to U-Boot and expects U-Boot to use a built-in one, however this ought to be a fairly trivial addition in the future.
The other significant difference to the x86 version is that rather than copying U-Boot to CONFIG_TEXT_OFFSET, we require that U-Boot is built position independent and copy it to EFI allocated memory.
Signed-off-by: Caleb Connolly caleb.connolly@linaro.org --- Makefile | 15 ++- arch/arm/cpu/armv8/config.mk | 11 ++ arch/arm/include/asm/global_data.h | 3 + arch/arm/lib/Makefile | 2 + include/efi.h | 2 +- lib/efi/Kconfig | 9 +- lib/efi/Makefile | 28 ++-- lib/efi/efi_info.c | 4 +- lib/efi/efi_stub_arm64.c | 236 +++++++++++++++++++++++++++++++++ lib/efi/{efi_stub.c => efi_stub_x86.c} | 0 10 files changed, 294 insertions(+), 16 deletions(-)
diff --git a/Makefile b/Makefile index da742ceae76e..8d0340622d7c 100644 --- a/Makefile +++ b/Makefile @@ -1681,21 +1681,32 @@ u-boot.bin.o: u-boot.bin FORCE
u-boot-payload.lds: $(LDSCRIPT_EFI) FORCE $(call if_changed_dep,cpp_lds)
+# Determine the file suffix for the efi stub implementation +EFI_STUB_ARCH := $(if $(CONFIG_ARM64),arm64,$(if $(CONFIG_X86_64),x86,$(ARCH))) + # Rule to link the EFI payload which contains a stub and a U-Boot binary quiet_cmd_u-boot_payload ?= LD $@ cmd_u-boot_payload ?= $(LD) $(LDFLAGS_EFI_PAYLOAD) -o $@ \ - -T u-boot-payload.lds arch/x86/cpu/call32.o \ - lib/efi/efi.o lib/efi/efi_stub.o u-boot.bin.o \ + -T u-boot-payload.lds $(if $(CONFIG_X86),arch/x86/cpu/call32.o,) \ + lib/efi/efi.o lib/efi/efi_stub_$(EFI_STUB_ARCH).o u-boot.bin.o \ $(addprefix arch/$(ARCH)/lib/,$(EFISTUB))
+quiet_cmd_u-boot_payload_arm64.efi ?= OBJCOPY $@ + cmd_u-boot_payload_arm64.efi ?= $(OBJCOPY) -O binary u-boot-payload $@ + u-boot-payload: u-boot.bin.o u-boot-payload.lds FORCE $(call if_changed,u-boot_payload)
OBJCOPYFLAGS_u-boot-payload.efi := $(OBJCOPYFLAGS_EFI) +ifeq ($(CONFIG_X86),y) u-boot-payload.efi: u-boot-payload FORCE $(call if_changed,zobjcopy) +else +u-boot-payload.efi: u-boot-payload FORCE + $(call if_changed,u-boot_payload_$(EFI_STUB_ARCH).efi) +endif
u-boot-img.bin: spl/u-boot-spl.bin u-boot.img FORCE $(call if_changed,cat)
diff --git a/arch/arm/cpu/armv8/config.mk b/arch/arm/cpu/armv8/config.mk index 4d74b2a533e0..1ee316801064 100644 --- a/arch/arm/cpu/armv8/config.mk +++ b/arch/arm/cpu/armv8/config.mk @@ -9,4 +9,15 @@ PLATFORM_CPPFLAGS += $(PF_NO_UNALIGNED)
EFI_LDS := elf_aarch64_efi.lds EFI_CRT0 := crt0_aarch64_efi.o EFI_RELOC := reloc_aarch64_efi.o + +LDSCRIPT_EFI := $(srctree)/arch/arm/lib/elf_aarch64_efi.lds +EFISTUB := crt0_aarch64_efi.o reloc_aarch64_efi.o +OBJCOPYFLAGS_EFI += --target=pei-aarch64-little +EFIPAYLOAD_BFDTARGET := pei-aarch64-little +EFIPAYLOAD_BFDARCH := aarch64 +LDFLAGS_EFI_PAYLOAD := -Bsymbolic -Bsymbolic-functions -shared --no-undefined \ + -s -zexecstack + +CPPFLAGS_REMOVE_crt0-efi-aarch64.o += $(CFLAGS_NON_EFI) +CPPFLAGS_crt0-efi-aarch64.o += $(CFLAGS_EFI) diff --git a/arch/arm/include/asm/global_data.h b/arch/arm/include/asm/global_data.h index 45401d5e3c8a..6e4471662a38 100644 --- a/arch/arm/include/asm/global_data.h +++ b/arch/arm/include/asm/global_data.h @@ -107,8 +107,11 @@ struct arch_global_data { #endif #ifdef CONFIG_SMBIOS ulong smbios_start; /* Start address of SMBIOS table */ #endif +#ifdef CONFIG_EFI_STUB + ulong table; +#endif };
#include <asm-generic/global_data.h>
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile index 1c95dd6fed21..14e3990925a7 100644 --- a/arch/arm/lib/Makefile +++ b/arch/arm/lib/Makefile @@ -130,4 +130,6 @@ CFLAGS_$(EFI_CRT0) := $(CFLAGS_EFI) CFLAGS_REMOVE_$(EFI_CRT0) := $(CFLAGS_NON_EFI)
CFLAGS_$(EFI_RELOC) := $(CFLAGS_EFI) CFLAGS_REMOVE_$(EFI_RELOC) := $(CFLAGS_NON_EFI) + +extra-$(CONFIG_EFI_STUB) += $(EFI_CRT0) $(EFI_RELOC) diff --git a/include/efi.h b/include/efi.h index c559fda3004c..a6eff13a6bbb 100644 --- a/include/efi.h +++ b/include/efi.h @@ -496,9 +496,9 @@ struct efi_media_plat { /* Base address of the EFI image */ extern char image_base[];
/* Start and end of U-Boot image (for payload) */ -extern char _binary_u_boot_bin_start[], _binary_u_boot_bin_end[]; +extern char _binary_u_boot_bin_start[], _binary_u_boot_bin_end[], _binary_u_boot_bin_size[];
/* * Variable Attributes */ diff --git a/lib/efi/Kconfig b/lib/efi/Kconfig index 81ed3e66b34d..18f69bdcfbec 100644 --- a/lib/efi/Kconfig +++ b/lib/efi/Kconfig @@ -1,10 +1,10 @@ menu "U-Boot as UEFI application" - depends on X86 + depends on X86 || ARM
config EFI bool "Support running U-Boot from EFI" - depends on X86 + depends on X86 || ARM imply X86_TSC_READ_BASE help U-Boot can be started from EFI on certain platforms. This allows EFI to perform most of the system init and then jump to U-Boot for @@ -12,12 +12,13 @@ config EFI application, with U-Boot using EFI's drivers instead of its own.
choice prompt "Select EFI mode to use" - depends on X86 && EFI + depends on EFI
config EFI_APP bool "Support running as an EFI application" + depends on !ARM select CHARSET help Build U-Boot as an application which can be started from EFI. This is useful for examining a platform in the early stages of porting @@ -25,8 +26,9 @@ config EFI_APP command prompt and memory and I/O functions. Use 'reset' to return to EFI.
config EFI_STUB + select POSITION_INDEPENDENT if ARM bool "Support running as an EFI payload"
endchoice
@@ -58,8 +60,9 @@ choice 32-bit EFI, select 32-bit here, else select 64-bit. Failure to do this may produce no error message - it just won't start!
config EFI_STUB_32BIT + depends on !ARM bool "Produce a stub for running with 32-bit EFI"
config EFI_STUB_64BIT bool "Produce a stub for running with 64-bit EFI" diff --git a/lib/efi/Makefile b/lib/efi/Makefile index 232fa684360e..bf65bacf47e7 100644 --- a/lib/efi/Makefile +++ b/lib/efi/Makefile @@ -4,14 +4,24 @@
obj-$(CONFIG_EFI_APP) += efi_app.o efi.o efi_app_init.o obj-$(CONFIG_EFI_STUB) += efi_info.o
-CFLAGS_REMOVE_efi_stub.o := -mregparm=3 \ - $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32) -CFLAGS_efi_stub.o := -fpic -fshort-wchar \ - $(if $(CONFIG_EFI_STUB_64BIT),-m64) -CFLAGS_REMOVE_efi.o := -mregparm=3 \ - $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32) -CFLAGS_efi.o := -fpic -fshort-wchar \ - $(if $(CONFIG_EFI_STUB_64BIT),-m64) +ifeq ($(CONFIG_ARM64),y) +efi_stub.o := efi_stub_arm64.o +else +efi_stub.o := efi_stub_x86.o
-extra-$(CONFIG_EFI_STUB) += efi_stub.o efi.o +ifeq ($(CONFIG_EFI_STUB_64BIT),y) # && !CONFIG_ARM64 +CFLAGS_REMOVE_$(efi_stub.o) := -march=i386 -m32 +CFLAGS_$(efi_stub.o) := -m64 +CFLAGS_REMOVE_efi.o := -march=i386 -m32 +CFLAGS_efi.o := -fpic -m64 +endif +endif + +CFLAGS_REMOVE_$(efi_stub.o) += -mregparm=3 +CFLAGS_$(efi_stub.o) += -fpic -fshort-wchar +CFLAGS_REMOVE_efi.o += -mregparm=3 +CFLAGS_efi.o += -fpic -fshort-wchar + +$(info removing flags $(CFLAGS_REMOVE_$(efi_stub.o))) +extra-$(CONFIG_EFI_STUB) += $(efi_stub.o) efi.o diff --git a/lib/efi/efi_info.c b/lib/efi/efi_info.c index 5b564c5651d5..5fa4baeec635 100644 --- a/lib/efi/efi_info.c +++ b/lib/efi/efi_info.c @@ -9,8 +9,10 @@ #include <errno.h> #include <mapmem.h> #include <asm/global_data.h>
+DECLARE_GLOBAL_DATA_PTR; + int efi_info_get(enum efi_entry_t type, void **datap, int *sizep) { struct efi_entry_hdr *entry; struct efi_info_hdr *info; @@ -41,6 +43,6 @@ int efi_info_get(enum efi_entry_t type, void **datap, int *sizep) ret = -ENOENT; err: unmap_sysmem(info);
- return ret; + return -ENOSYS; } diff --git a/lib/efi/efi_stub_arm64.c b/lib/efi/efi_stub_arm64.c new file mode 100644 index 000000000000..54bee6c55d7e --- /dev/null +++ b/lib/efi/efi_stub_arm64.c @@ -0,0 +1,236 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2015 Google, Inc + * Copyright (c) 2024 Linaro, Ltd. + * + * EFI information obtained here: + * http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES + * + * Call ExitBootServices() and launch U-Boot from an EFI environment. + */ + +#include <debug_uart.h> +#include <efi.h> +#include <efi_api.h> +#include <malloc.h> +#include <asm/io.h> +#include <linux/err.h> +#include <linux/types.h> + +static bool ebs_called; + +void _debug_uart_putc(int ch) +{ + struct efi_priv *priv = efi_get_priv(); + + if (ch == '\n') + _debug_uart_putc('\r'); + /* + * After calling EBS we can't log anywhere. + * NOTE: for development it is possible to re-implement + * your boards debug uart here like in efi_stub.c for x86. + */ + if (!ebs_called) + efi_putc(priv, ch); +} + +void _debug_uart_init(void) {} + +DEBUG_UART_FUNCS; + +void putc(const char ch) +{ + _debug_uart_putc(ch); +} + +void puts(const char *str) +{ + while (*str) + putc(*str++); +} + + +void *memcpy(void *dest, const void *src, size_t size) +{ + unsigned char *dptr = dest; + const unsigned char *ptr = src; + const unsigned char *end = src + size; + + while (ptr < end) + *dptr++ = *ptr++; + + return dest; +} + +void *memset(void *inptr, int ch, size_t size) +{ + char *ptr = inptr; + char *end = ptr + size; + + while (ptr < end) + *ptr++ = ch; + + return ptr; +} + +/** + * setup_info_table() - sets up a table containing information from EFI + * + * We must call exit_boot_services() before jumping out of the stub into U-Boot + * proper, so that U-Boot has full control of peripherals, memory, etc. + * + * Once we do this, we cannot call any boot-services functions so we must find + * out everything we need to before doing that. + * + * Set up a struct efi_info_hdr table which can hold various records (e.g. + * struct efi_entry_memmap) with information obtained from EFI. + * + * @priv: Pointer to our private information which contains the list + * @size: Size of the table to allocate + * Return: 0 if OK, non-zero on error + */ +static int setup_info_table(struct efi_priv *priv, int size) +{ + struct efi_info_hdr *info; + efi_status_t ret; + + /* Get some memory for our info table */ + priv->info_size = size; + info = efi_malloc(priv, priv->info_size, &ret); + if (ret) { + printhex2(ret); + puts(" No memory for info table: "); + return ret; + } + + memset(info, '\0', sizeof(*info)); + info->version = EFI_TABLE_VERSION; + info->hdr_size = sizeof(*info); + priv->info = info; + priv->next_hdr = (char *)info + info->hdr_size; + + return 0; +} + +/** + * add_entry_addr() - Add a new entry to the efi_info list + * + * This adds an entry, consisting of a tag and two lots of data. This avoids the + * caller having to coalesce the data first + * + * @priv: Pointer to our private information which contains the list + * @type: Type of the entry to add + * @ptr1: Pointer to first data block to add + * @size1: Size of first data block in bytes (can be 0) + * @ptr2: Pointer to second data block to add + * @size2: Size of second data block in bytes (can be 0) + */ +static void add_entry_addr(struct efi_priv *priv, enum efi_entry_t type, + void *ptr1, int size1, void *ptr2, int size2) +{ + struct efi_entry_hdr *hdr = priv->next_hdr; + + hdr->type = type; + hdr->size = size1 + size2; + hdr->addr = 0; + hdr->link = ALIGN(sizeof(*hdr) + hdr->size, 16); + priv->next_hdr += hdr->link; + memcpy(hdr + 1, ptr1, size1); + memcpy((void *)(hdr + 1) + size1, ptr2, size2); + priv->info->total_size = (ulong)priv->next_hdr - (ulong)priv->info; +} + +/** + * efi_main() - Start an EFI image + * + * This function is called by our EFI start-up code. It handles running + * U-Boot. If it returns, EFI will continue. + */ +efi_status_t EFIAPI efi_main(efi_handle_t image, + struct efi_system_table *sys_table) +{ + struct efi_priv local_priv, *priv = &local_priv; + struct efi_boot_services *boot = sys_table->boottime; + struct efi_entry_memmap map; + struct efi_gop *gop; + struct efi_entry_gopmode mode; + struct efi_entry_systable table; + efi_guid_t efi_gop_guid = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID; + efi_status_t ret; + + ebs_called = false; + + ret = efi_init(priv, "Payload", image, sys_table); + if (ret) { + printhex2(ret); + puts(" efi_init() failed\n"); + return ret; + } + efi_set_priv(priv); + + phys_addr_t reloc_addr = ULONG_MAX; + ret = boot->allocate_pages(EFI_ALLOCATE_MAX_ADDRESS, EFI_LOADER_CODE, + (phys_addr_t)_binary_u_boot_bin_size / EFI_PAGE_SIZE, + &reloc_addr); + if (ret != EFI_SUCCESS) { + puts("Failed to allocate memory for U-Boot: "); + printhex2(ret); + putc('\n'); + return ret; + } + + ret = efi_store_memory_map(priv); + if (ret) + return ret; + + ret = setup_info_table(priv, priv->memmap_size + 128); + if (ret) + return ret; + + ret = boot->locate_protocol(&efi_gop_guid, NULL, (void **)&gop); + if (ret) { + puts(" GOP unavailable\n"); + } else { + mode.fb_base = gop->mode->fb_base; + mode.fb_size = gop->mode->fb_size; + mode.info_size = gop->mode->info_size; + add_entry_addr(priv, EFIET_GOP_MODE, &mode, sizeof(mode), + gop->mode->info, + sizeof(struct efi_gop_mode_info)); + } + + table.sys_table = (ulong)sys_table; + add_entry_addr(priv, EFIET_SYS_TABLE, &table, sizeof(table), NULL, 0); + + ret = efi_call_exit_boot_services(); + if (ret) + return ret; + + /* The EFI console won't work now :( */ + ebs_called = true; + + map.version = priv->memmap_version; + map.desc_size = priv->memmap_desc_size; + add_entry_addr(priv, EFIET_MEMORY_MAP, &map, sizeof(map), + priv->memmap_desc, priv->memmap_size); + add_entry_addr(priv, EFIET_END, NULL, 0, 0, 0); + + memcpy((void *)reloc_addr, _binary_u_boot_bin_start, + (ulong)_binary_u_boot_bin_end - + (ulong)_binary_u_boot_bin_start); + +/* This will only work if you patched your own debug uart into this file. */ +#ifdef DEBUG + puts("EFI table at "); + printhex8((ulong)priv->info); + puts(" size "); + printhex8(priv->info->total_size); + putc('\n'); +#endif + typedef void (*func_t)(u64 x0, u64 x1, u64 x2, u64 x3); + + puts("Jumping to U-Boot\n"); + ((func_t)reloc_addr)((phys_addr_t)priv->info, 0, 0, 0); + + return EFI_LOAD_ERROR; +} diff --git a/lib/efi/efi_stub.c b/lib/efi/efi_stub_x86.c similarity index 100% rename from lib/efi/efi_stub.c rename to lib/efi/efi_stub_x86.c