Re: [U-Boot] [PATCH v3 08/28] x86: Add support for U-Boot as an EFI application

On Wed, Aug 5, 2015 at 2:33 AM, Simon Glass sjg@chromium.org wrote:

From: Ben Stoltz stoltz@google.com

Add the required x86 glue code. This includes the initial start-up, relocation and jumping to efi_main(). We also need to avoid fiddling with interrupts.

Signed-off-by: Ben Stoltz stoltz@google.com Signed-off-by: Simon Glass sjg@chromium.org

---

Changes in v3:

• Move u-boot-app.efi Makefile change to the earlier patch
• Use "BSD-2-Clause" for the SPDX license

Changes in v2:

• Add ALIGN() before .dynamic in the linker script
• Add a blank line before return in the _relocate() function
• Add a comment as to why .hash has to be first in the linker script
• Add a comment as to why interrupt_init() must be skipped for EFI
• Drop unused DECLARE_GLOBAL_DATA_INIT
• Drop unused board_eth_init()
• Drop use of CONFIG_X86_64 since we don't support a 64-bit EFI application yet
• Fix spacing around operators
• Move 64-bit crt0 to a later patch
• Move crt0 and reloc files into arch/x86/lib/efi/
• Remove KEEP in the EFI linker script since garbage collection is not enabled
• Rename CONFIG_ARCH_EFI to CONFIG_EFI_APP
• Rename ImageBase to image_base
• Use SPDX for the EFI start and relocation code
• Use u-boot-app.efi instead of u-boot.efi

arch/x86/Kconfig | 3 ++ arch/x86/Makefile | 2 + arch/x86/cpu/Makefile | 1 + arch/x86/cpu/efi/Makefile | 8 +++ arch/x86/cpu/efi/efi.c | 42 ++++++++++++++++ arch/x86/cpu/efi/elf_ia32_efi.lds | 94 ++++++++++++++++++++++++++++++++++++ arch/x86/cpu/efi/sdram.c | 29 +++++++++++ arch/x86/cpu/interrupts.c | 6 +++ arch/x86/include/asm/arch-efi/gpio.h | 10 ++++ arch/x86/lib/efi/crt0-efi-ia32.S | 52 ++++++++++++++++++++ arch/x86/lib/efi/reloc_ia32.c | 72 +++++++++++++++++++++++++++ 11 files changed, 319 insertions(+) create mode 100644 arch/x86/cpu/efi/Makefile create mode 100644 arch/x86/cpu/efi/efi.c create mode 100644 arch/x86/cpu/efi/elf_ia32_efi.lds create mode 100644 arch/x86/cpu/efi/sdram.c create mode 100644 arch/x86/include/asm/arch-efi/gpio.h create mode 100644 arch/x86/lib/efi/crt0-efi-ia32.S create mode 100644 arch/x86/lib/efi/reloc_ia32.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e8968a7..7e6e89c 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -11,6 +11,9 @@ choice config VENDOR_COREBOOT bool "coreboot"

+config VENDOR_EFI

•   bool "efi"
  

config VENDOR_EMULATION bool "emulation"

diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 36a6018..d104a49 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -2,7 +2,9 @@ # SPDX-License-Identifier: GPL-2.0+ #

+ifeq ($(CONFIG_EFI_APP),) head-y := arch/x86/cpu/start.o +endif ifeq ($(CONFIG_SPL_BUILD),y) head-y += arch/x86/cpu/start16.o head-y += arch/x86/cpu/resetvec.o diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile index 8a8e63e..5e058c0 100644 --- a/arch/x86/cpu/Makefile +++ b/arch/x86/cpu/Makefile @@ -14,6 +14,7 @@ obj-y += interrupts.o cpu.o cpu_x86.o call64.o

obj-$(CONFIG_INTEL_BAYTRAIL) += baytrail/ obj-$(CONFIG_SYS_COREBOOT) += coreboot/ +obj-$(CONFIG_EFI_APP) += efi/ obj-$(CONFIG_QEMU) += qemu/ obj-$(CONFIG_NORTHBRIDGE_INTEL_SANDYBRIDGE) += ivybridge/ obj-$(CONFIG_NORTHBRIDGE_INTEL_IVYBRIDGE) += ivybridge/ diff --git a/arch/x86/cpu/efi/Makefile b/arch/x86/cpu/efi/Makefile new file mode 100644 index 0000000..e091637 --- /dev/null +++ b/arch/x86/cpu/efi/Makefile @@ -0,0 +1,8 @@ +# +# Copyright (c) 2015 Google, Inc +# +# SPDX-License-Identifier: GPL-2.0+ +#

+obj-y += efi.o +obj-y += sdram.o diff --git a/arch/x86/cpu/efi/efi.c b/arch/x86/cpu/efi/efi.c new file mode 100644 index 0000000..75ba0d4 --- /dev/null +++ b/arch/x86/cpu/efi/efi.c @@ -0,0 +1,42 @@ +/*

• • Copyright (c) 2015 Google, Inc
• • SPDX-License-Identifier: GPL-2.0+
• */

+#include <common.h> +#include <fdtdec.h> +#include <netdev.h>

+int arch_cpu_init(void) +{ +#ifdef CONFIG_SYS_X86_TSC_TIMER

•   timer_set_base(rdtsc());
  

+#endif

•   return 0;
  

+}

+int board_early_init_f(void) +{

•   return 0;
  

+}

+int print_cpuinfo(void) +{

•   return default_print_cpuinfo();
  

+}

+void board_final_cleanup(void) +{ +}

+int misc_init_r(void) +{

•   return 0;
  

+}

+int arch_misc_init(void) +{

•   return 0;
  

+} diff --git a/arch/x86/cpu/efi/elf_ia32_efi.lds b/arch/x86/cpu/efi/elf_ia32_efi.lds new file mode 100644 index 0000000..cd3b0a9 --- /dev/null +++ b/arch/x86/cpu/efi/elf_ia32_efi.lds @@ -0,0 +1,94 @@ +/*

• • U-Boot EFI linker script
• • SPDX-License-Identifier: BSD-2-Clause
• • Modified from usr/lib32/elf_ia32_efi.lds in gnu-efi
• */

+#include <config.h>

+OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") +OUTPUT_ARCH(i386) +ENTRY(_start) +SECTIONS +{

•   image_base = .;
  

•   .hash : { *(.hash) }    /* this MUST come first, EFI expects it */
  

•   . = ALIGN(4096);
  

•   .text :
  

•   {
  

•           *(.text)
  

•           *(.text.*)
  

•           *(.gnu.linkonce.t.*)
  

•   }
  

•   . = ALIGN(4096);
  

•   .sdata :
  

•   {
  

•           *(.got.plt)
  

•           *(.got)
  

•           *(.srodata)
  

•           *(.sdata)
  

•           *(.sbss)
  

•           *(.scommon)
  

•   }
  

•   . = ALIGN(4096);
  

•   .data :
  

•   {
  

•           *(.rodata*)
  

•           *(.data)
  

•           *(.data1)
  

•           *(.data.*)
  

•           *(.sdata)
  

•           *(.got.plt)
  

•           *(.got)
  

•           /*
  

•            * the EFI loader doesn't seem to like a .bss section, so we
  

•            * stick it all into .data:
  

•            */
  

•           *(.sbss)
  

•           *(.scommon)
  

•           *(.dynbss)
  

•           *(.bss)
  

•           *(COMMON)
  

•           /* U-Boot lists and device tree */
  

•           . = ALIGN(8);
  

•           *(SORT(.u_boot_list*));
  

•           . = ALIGN(8);
  

•           *(.dtb*);
  

•   }
  

•   . = ALIGN(4096);
  

•   .dynamic  : { *(.dynamic) }
  

•   . = ALIGN(4096);
  

•   .rel :
  

•   {
  

•           *(.rel.data)
  

•           *(.rel.data.*)
  

•           *(.rel.got)
  

•           *(.rel.stab)
  

•           *(.data.rel.ro.local)
  

•           *(.data.rel.local)
  

•           *(.data.rel.ro)
  

•           *(.data.rel*)
  

•           *(.rel.u_boot_list*)
  

•   }
  

•   . = ALIGN(4096);
  

•           .reloc :        /* This is the PECOFF .reloc section! */
  

•   {
  

•   *(.reloc)
  

•   }
  

•   . = ALIGN(4096);
  

•   .dynsym   : { *(.dynsym) }
  

•   . = ALIGN(4096);
  

•   .dynstr   : { *(.dynstr) }
  

•   . = ALIGN(4096);
  

•   /DISCARD/ :
  

•   {
  

•           *(.rel.reloc)
  

•           *(.eh_frame)
  

•           *(.note.GNU-stack)
  

•   }
  

•   .comment 0 : { *(.comment) }
  

+} diff --git a/arch/x86/cpu/efi/sdram.c b/arch/x86/cpu/efi/sdram.c new file mode 100644 index 0000000..5159944 --- /dev/null +++ b/arch/x86/cpu/efi/sdram.c @@ -0,0 +1,29 @@ +/*

• • Copyright (c) 2015 Google, Inc
• • SPDX-License-Identifier: GPL-2.0+
• */

+#include <common.h> +#include <efi.h> +#include <asm/u-boot-x86.h>

+DECLARE_GLOBAL_DATA_PTR;

+ulong board_get_usable_ram_top(ulong total_size) +{

•   return (ulong)efi_get_ram_base() + gd->ram_size;
  

+}

+int dram_init(void) +{

•   /* gd->ram_size is set as part of EFI init */
  

•   return 0;
  

+}

+void dram_init_banksize(void) +{

•   gd->bd->bi_dram[0].start = efi_get_ram_base();
  

•   gd->bd->bi_dram[0].size = CONFIG_EFI_RAM_SIZE;
  

+} diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c index 3a9c2d4..a112938 100644 --- a/arch/x86/cpu/interrupts.c +++ b/arch/x86/cpu/interrupts.c @@ -242,6 +242,11 @@ int disable_interrupts(void)

int interrupt_init(void) {

•   /*
  

•    * When running as an EFI application we are not in control of
  

•    * interrupts and should leave them alone.
  

•    */
  

+#ifndef CONFIG_EFI_APP /* Just in case... */ disable_interrupts();

@@ -255,6 +260,7 @@ int interrupt_init(void)

    /* It is now safe to enable interrupts */
    enable_interrupts();

+#endif

    return 0;

} diff --git a/arch/x86/include/asm/arch-efi/gpio.h b/arch/x86/include/asm/arch-efi/gpio.h new file mode 100644 index 0000000..f044f07 --- /dev/null +++ b/arch/x86/include/asm/arch-efi/gpio.h @@ -0,0 +1,10 @@ +/*

• • Copyright (c) 2015 Google, Inc.
• • SPDX-License-Identifier: GPL-2.0+
• */

+#ifndef _X86_ARCH_GPIO_H_ +#define _X86_ARCH_GPIO_H_

+#endif /* _X86_ARCH_GPIO_H_ */ diff --git a/arch/x86/lib/efi/crt0-efi-ia32.S b/arch/x86/lib/efi/crt0-efi-ia32.S new file mode 100644 index 0000000..30e5eb0 --- /dev/null +++ b/arch/x86/lib/efi/crt0-efi-ia32.S @@ -0,0 +1,52 @@ +/*

• • crt0-efi-ia32.S - x86 EFI startup code.
• • Copyright (C) 1999 Hewlett-Packard Co.
• • Contributed by David Mosberger davidm@hpl.hp.com.
• • All rights reserved.
• • SPDX-License-Identifier: BSD-3-Clause
• */

•   .text
  

•   .align 4
  

•   .globl _start
  

+_start:

•   pushl %ebp
  

•   movl %esp,%ebp
  

•   pushl 12(%ebp)                  # copy "image" argument
  

•   pushl  8(%ebp)                  # copy "systab" argument
  

•   call 0f
  

+0: popl %eax

•   movl %eax,%ebx
  

•   addl $image_base-0b,%eax        # %eax = ldbase
  

•   addl $_DYNAMIC-0b,%ebx          # %ebx = _DYNAMIC
  

•   pushl %ebx                      # pass _DYNAMIC as second argument
  

•   pushl %eax                      # pass ldbase as first argument
  

•   call _relocate
  

•   popl %ebx
  

•   popl %ebx
  

•   testl %eax,%eax
  

•   jne .exit
  

•   call efi_main           # call app with "image" and "systab" argument
  

+.exit: leave

•   ret
  

•   /*
  

•    * hand-craft a dummy .reloc section so EFI knows it's a relocatable
  

•    * executable:
  

•    */
  

•   .data
  

+dummy: .long 0

+#define IMAGE_REL_ABSOLUTE 0

•   .section .reloc
  

•   .long   dummy                                   /* Page RVA */
  

•   .long   10                                      /* Block Size (2*4+2) */
  

•   .word   (IMAGE_REL_ABSOLUTE << 12) +  0         /* reloc for dummy */
  

diff --git a/arch/x86/lib/efi/reloc_ia32.c b/arch/x86/lib/efi/reloc_ia32.c new file mode 100644 index 0000000..4d68255 --- /dev/null +++ b/arch/x86/lib/efi/reloc_ia32.c @@ -0,0 +1,72 @@ +/*

• • reloc_ia32.c - position independent x86 ELF shared object relocator
• • Copyright (C) 1999 Hewlett-Packard Co.
• • Contributed by David Mosberger davidm@hpl.hp.com.
• • All rights reserved.
• • SPDX-License-Identifier: BSD-3-Clause
• */

+#include <common.h> +#include <efi.h> +#include <elf.h> +#include <asm/elf.h>

+efi_status_t _relocate(long ldbase, Elf32_Dyn *dyn, efi_handle_t image,

•                  struct efi_system_table *systab)
  

+{

•   long relsz = 0, relent = 0;
  

•   Elf32_Rel *rel = 0;
  

•   unsigned long *addr;
  

•   int i;
  

•   for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
  

•           switch (dyn[i].d_tag) {
  

•           case DT_REL:
  

•                   rel = (Elf32_Rel *)((unsigned long)dyn[i].d_un.d_ptr +
  

•                                                           ldbase);
  

•                   break;
  

•           case DT_RELSZ:
  

•                   relsz = dyn[i].d_un.d_val;
  

•                   break;
  

•           case DT_RELENT:
  

•                   relent = dyn[i].d_un.d_val;
  

•                   break;
  

•           case DT_RELA:
  

•                   break;
  

•           default:
  

•                   break;
  

•           }
  

•   }
  

•   if (!rel && relent == 0)
  

•           return EFI_SUCCESS;
  

•   if (!rel || relent == 0)
  

•           return EFI_LOAD_ERROR;
  

•   while (relsz > 0) {
  

•           /* apply the relocs */
  

•           switch (ELF32_R_TYPE(rel->r_info)) {
  

•           case R_386_NONE:
  

•                   break;
  

•           case R_386_RELATIVE:
  

•                   addr = (unsigned long *)(ldbase + rel->r_offset);
  

•                   *addr += ldbase;
  

•                   break;
  

•           default:
  

•                   break;
  

•           }
  

•           rel = (Elf32_Rel *)((char *)rel + relent);
  

•           relsz -= relent;
  

•   }
  

•   return EFI_SUCCESS;
  

+}

Reviewed-by: Bin Meng bmeng.cn@gmail.com