Re: [U-Boot] [PATCH v3 18/28] efi: Add 64-bit payload support

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

Most EFI implementations use 64-bit. Add a way to build U-Boot as a 64-bit EFI payload. The payload unpacks a (32-bit) U-Boot and starts it. This can be enabled for x86 boards at present.

Signed-off-by: Simon Glass sjg@chromium.org Improvements to how the payload is built: Signed-off-by: Bin Meng bmeng.cn@gmail.com

---

Changes in v3:

• Add spaces around EFIARCH=
• Use CONFIG_SYS_MONITOR_LEN as a more accurate value for U-Boot's size

Changes in v2:

• Add -no-red-zone for 64-bit only
• Check the GDT selector's base and limit against the target address
• Drop use of CONFIG_X86_64 since we don't support a 64-bit EFI application yet
• Merge in Bin's implementation of adding a U-Boot payload with objcopy
• Move the 64-bit crt and reloc code into this patch
• Move the 64-bit efi.h additions into this patch
• Rename GDT_4GB to GDT_4KB

Makefile | 2 +- arch/x86/config.mk | 10 ++++++ arch/x86/include/asm/types.h | 5 ++- arch/x86/lib/efi/crt0-efi-x86_64.S | 51 ++++++++++++++++++++++++++ include/efi.h | 7 ++++ lib/efi/efi_stub.c | 74 +++++++++++++++++++++++++++++++++++--- 6 files changed, 143 insertions(+), 6 deletions(-) create mode 100644 arch/x86/lib/efi/crt0-efi-x86_64.S

diff --git a/Makefile b/Makefile index 752ee0d..bb0ba9f 100644 --- a/Makefile +++ b/Makefile @@ -1100,7 +1100,7 @@ u-boot-payload.lds: $(LDSCRIPT_EFI) FORCE # 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 \
  

•  -T u-boot-payload.lds arch/x86/cpu/call32.o \
   lib/efi/efi.o lib/efi/efi_stub.o u-boot-dtb.bin.o \
   $(addprefix arch/$(ARCH)/lib/efi/,$(EFISTUB))
  
  

diff --git a/arch/x86/config.mk b/arch/x86/config.mk index 334c10b..d7addd8 100644 --- a/arch/x86/config.mk +++ b/arch/x86/config.mk @@ -34,14 +34,24 @@ OBJCOPYFLAGS_EFI := -j .text -j .sdata -j .data -j .dynamic -j .dynsym \ CFLAGS_NON_EFI := -mregparm=3 CFLAGS_EFI := -fpic -fshort-wchar

+ifeq ($(CONFIG_EFI_STUB_64BIT),) +CFLAGS_EFI += $(call cc-option, -mno-red-zone) EFIARCH = ia32 EFIPAYLOAD_BFDTARGET = elf32-i386 +else +EFIARCH = x86_64 +EFIPAYLOAD_BFDTARGET = elf64-x86-64 +endif

EFIPAYLOAD_BFDARCH = i386

LDSCRIPT_EFI := $(srctree)/$(CPUDIR)/efi/elf_$(EFIARCH)_efi.lds +EFISTUB := crt0-efi-$(EFIARCH).o reloc_$(EFIARCH).o OBJCOPYFLAGS_EFI += --target=efi-app-$(EFIARCH)

+CPPFLAGS_REMOVE_crt0-efi-$(EFIARCH).o += $(CFLAGS_NON_EFI) +CPPFLAGS_crt0-efi-$(EFIARCH).o += $(CFLAGS_EFI)

ifeq ($(CONFIG_EFI_APP),y)

PLATFORM_CPPFLAGS += $(CFLAGS_EFI) diff --git a/arch/x86/include/asm/types.h b/arch/x86/include/asm/types.h index e272c90..766617f 100644 --- a/arch/x86/include/asm/types.h +++ b/arch/x86/include/asm/types.h @@ -44,8 +44,11 @@ typedef __INT64_TYPE__ s64; typedef __UINT64_TYPE__ u64; #endif

+#ifdef CONFIG_EFI_STUB_64BIT +#define BITS_PER_LONG 64 +#else #define BITS_PER_LONG 32

+#endif /* Dma addresses are 32-bits wide. */

typedef u32 dma_addr_t; diff --git a/arch/x86/lib/efi/crt0-efi-x86_64.S b/arch/x86/lib/efi/crt0-efi-x86_64.S new file mode 100644 index 0000000..c5cbf41 --- /dev/null +++ b/arch/x86/lib/efi/crt0-efi-x86_64.S @@ -0,0 +1,51 @@ +/*

• • crt0-efi-x86_64.S - x86_64 EFI startup code.
• • Copyright (C) 1999 Hewlett-Packard Co.
• • Contributed by David Mosberger davidm@hpl.hp.com.
• • Copyright (C) 2005 Intel Co.
• • Contributed by Fenghua Yu fenghua.yu@intel.com.
• • All rights reserved.
• • SPDX-License-Identifier: BSD-3-Clause
• */

•   .text
  

•   .align 4
  

•   .globl _start
  

+_start:

•   subq $8, %rsp
  

•   pushq %rcx
  

•   pushq %rdx
  

+0:

•   lea image_base(%rip), %rdi
  

•   lea _DYNAMIC(%rip), %rsi
  

•   popq %rcx
  

•   popq %rdx
  

•   pushq %rcx
  

•   pushq %rdx
  

•   call _relocate
  

•   popq %rdi
  

•   popq %rsi
  

•   call efi_main
  

•   addq $8, %rsp
  

+.exit:

•   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, "a"
  

+label1:

•   .long   dummy-label1                            /* Page RVA */
  

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

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

diff --git a/include/efi.h b/include/efi.h index 1470c08..fcafda0 100644 --- a/include/efi.h +++ b/include/efi.h @@ -18,6 +18,13 @@ #include <linux/string.h> #include <linux/types.h>

+#ifdef CONFIG_EFI_STUB_64BIT +/* EFI uses the Microsoft ABI which is not the default for GCC */ +#define EFIAPI __attribute__((ms_abi)) +#else +#define EFIAPI +#endif

struct efi_device_path;

#define EFI_SUCCESS 0 diff --git a/lib/efi/efi_stub.c b/lib/efi/efi_stub.c index 1e46f6e..d4d3e49 100644 --- a/lib/efi/efi_stub.c +++ b/lib/efi/efi_stub.c @@ -6,8 +6,8 @@

• EFI information obtained here:
• http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES

• • Loads a payload (U-Boot) within the EFI environment. This is built as a
• • 32-bit EFI application.

• • Loads a payload (U-Boot) within the EFI environment. This is built as an
• • EFI application. It can be built either in 32-bit or 64-bit mode.
  */

#include <common.h> @@ -126,14 +126,16 @@ static void jump_to_uboot(ulong cs32, ulong addr, ulong info)

    ((func_t)addr)(0, 0, info);

#else

•   /* TODO: Implement this */
  

•   cpu_call32(cs32, CONFIG_SYS_TEXT_BASE, info);
  

#endif }

+#ifdef CONFIG_EFI_STUB_64BIT static void get_gdt(struct desctab_info *info) { asm volatile ("sgdt %0" : : "m"(*info) : "memory"); } +#endif

static inline unsigned long read_cr3(void) { @@ -156,7 +158,71 @@ static int get_codeseg32(void) { int cs32 = 0;

•   /* TODO(sjg): Implement this for 64-bit mode */
  

+#ifdef CONFIG_EFI_STUB_64BIT

•   struct desctab_info gdt;
  

•   uint64_t *ptr;
  

•   int i;
  

•   get_gdt(&gdt);
  

•   for (ptr = (uint64_t *)(unsigned long)gdt.addr, i = 0; i < gdt.limit;
  

•        i += 8, ptr++) {
  

•           uint64_t desc = *ptr;
  

•           uint64_t base, limit;
  

•           /*
  

•            * Check that the target U-Boot jump address is within the
  

•            * selector and that the selector is of the right type.
  

•            */
  

•           base = ((desc >> GDT_BASE_LOW_SHIFT) & GDT_BASE_LOW_MASK) |
  

•                   ((desc >> GDT_BASE_HIGH_SHIFT) & GDT_BASE_HIGH_MASK)
  

•                           << 16;
  

•           limit = ((desc >> GDT_LIMIT_LOW_SHIFT) & GDT_LIMIT_LOW_MASK) |
  

•                   ((desc >> GDT_LIMIT_HIGH_SHIFT) & GDT_LIMIT_HIGH_MASK)
  

•                           << 16;
  

•           base <<= 12;    /* 4KB granularity */
  

•           limit <<= 12;
  

•           if ((desc & GDT_PRESENT) && (desc && GDT_NOTSYS) &&
  

•               !(desc & GDT_LONG) && (desc & GDT_4KB) &&
  

•               (desc & GDT_32BIT) && (desc & GDT_CODE) &&
  

•               CONFIG_SYS_TEXT_BASE > base &&
  

•               CONFIG_SYS_TEXT_BASE + CONFIG_SYS_MONITOR_LEN < limit
  

•           ) {
  

•                   cs32 = i;
  

•                   break;
  

•           }
  

•   }
  

+#ifdef DEBUG

•   puts("\ngdt: ");
  

•   printhex8(gdt.limit);
  

•   puts(", addr: ");
  

•   printhex8(gdt.addr >> 32);
  

•   printhex8(gdt.addr);
  

•   for (i = 0; i < gdt.limit; i += 8) {
  

•           uint32_t *ptr = (uint32_t *)((unsigned long)gdt.addr + i);
  

•           puts("\n");
  

•           printhex2(i);
  

•           puts(": ");
  

•           printhex8(ptr[1]);
  

•           puts("  ");
  

•           printhex8(ptr[0]);
  

•   }
  

•   puts("\n ");
  

•   puts("32-bit code segment: ");
  

•   printhex2(cs32);
  

•   puts("\n ");
  

•   puts("page_table: ");
  

•   printhex8(read_cr3());
  

•   puts("\n ");
  

+#endif

•   if (!cs32) {
  

•           puts("Can't find 32-bit code segment\n");
  

•           return -ENOENT;
  

•   }
  

+#endif

•   return cs32;
  

}

--

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

Tested on QEMU 32-bit and 64-bit Tested-by: Bin Meng bmeng.cn@gmail.com