Re: [edk2-devel] [edk2-staging/RISC-V-V2 PATCH v2 25/29] BaseTools/Scripts

["Leif Lindholm" <leif.lindholm@linaro.org>]

On Mon, Sep 23, 2019 at 08:31:51AM +0800, Abner Chang wrote:
> Add RISC-V specific LD scripts. ."rela(INFO)" in the latest GccBase.lds
> causes PE32 relocation error.
> This is the temporaty solution untill we find the root casue.

I presume you mean that having a separate version for RISCV is
temporary? I am OK with this for now. However, the diff is not what I
would expect. Can you verify that the difference is only what you
actually need?

For example:

> Signed-off-by: Abner Chang <abner.chang@hpe.com>
> ---
>  BaseTools/Scripts/GccBaseRiscV.lds | 66 ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 66 insertions(+)
>  create mode 100644 BaseTools/Scripts/GccBaseRiscV.lds
> 
> diff --git a/BaseTools/Scripts/GccBaseRiscV.lds b/BaseTools/Scripts/GccBaseRiscV.lds
> new file mode 100644
> index 0000000..7f9fae6
> --- /dev/null
> +++ b/BaseTools/Scripts/GccBaseRiscV.lds
> @@ -0,0 +1,66 @@
> +/** @file
> +
> +  Unified linker script for GCC based builds
> +
> +  Copyright (c) 2010 - 2015, Intel Corporation. All rights reserved.<BR>
> +  Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR>
> +  Copyright (c) 2019, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
> +
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +SECTIONS {
> +
> +  /*
> +   * The PE/COFF binary consists of DOS and PE/COFF headers, and a sequence of
> +   * section headers adding up to PECOFF_HEADER_SIZE bytes (which differs
> +   * between 32-bit and 64-bit builds). The actual start of the .text section
> +   * will be rounded up based on its actual alignment.
> +   */
> +  . = PECOFF_HEADER_SIZE;
> +
> +  .text : ALIGN(CONSTANT(COMMONPAGESIZE)) {
> +    *(.text .text.* .stub .gnu.linkonce.t.*)
> +    *(.rodata .rodata.* .gnu.linkonce.r.*)
> +    *(.got .got.*)
> +
> +    /*
> +     * The contents of AutoGen.c files are constant from the POV of the program,
> +     * but most of its contents end up in .data or .bss by default since few of
> +     * the variable definitions that get emitted are declared as CONST.
> +     */

The above comment block looks completely different - in GccBase.lds:
     /*
      * The contents of AutoGen.c files are mostly constant from the POV of the
      * program, but most of it ends up in .data or .bss by default since few of
      * the variable definitions that get emitted are declared as CONST.
      * Unfortunately, we cannot pull it into the .text section entirely, since
      * patchable PCDs are also emitted here, but we can at least move all of the
      * emitted GUIDs here.
      */

> +    *:AutoGen.obj(.data.g*Guid)
> +  }
> +
> +  /*
> +   * The alignment of the .data section should be less than or equal to the
> +   * alignment of the .text section. This ensures that the relative offset
> +   * between these sections is the same in the ELF and the PE/COFF versions of
> +   * this binary.
> +   */
> +  .data ALIGN(ALIGNOF(.text)) : ALIGN(CONSTANT(COMMONPAGESIZE)) {
> +    *(.data .data.* .gnu.linkonce.d.*)
> +    *(.bss .bss.*)
> +  }
> +
> +  .eh_frame ALIGN(CONSTANT(COMMONPAGESIZE)) : {
> +    KEEP (*(.eh_frame))
> +  }
> +
> +  .rela ALIGN(CONSTANT(COMMONPAGESIZE)) : {

The above line is, I believe, the only necessary change for your workaround?

> +    *(.rela .rela.*)
> +  }
> +

The original one as the following:
  .hii : ALIGN(CONSTANT(COMMONPAGESIZE)) {
    KEEP (*(.hii))
  }

I do not think including this could be the cause of any issues.

Also, GccBase.lds includes here:
  /*
   * Retain the GNU build id but in a non-allocatable section so GenFw
   * does not copy it into the PE/COFF image.
   */
  .build-id (INFO) : { *(.note.gnu.build-id) }

> +  /DISCARD/ : {
> +    *(.note.GNU-stack)
> +    *(.gnu_debuglink)
> +    *(.interp)
> +    *(.dynsym)
> +    *(.dynstr)
> +    *(.dynamic)
> +    *(.hash)

In GccBase.lds:
       *(.hash .gnu.hash)

/
    Leif

> +    *(.comment)
> +    *(COMMON)
> +  }
> +}
> -- 
> 2.7.4
> 
> 
> 
>