diff mbox series

[v6,07/11] RISC-V: Add awareness for RISC-V reloations

Message ID 20190212103108.56963-8-agraf@suse.de
State Accepted
Commit e0d32cca1d5a0d8db9fb2e0fa43c86599c79f6a7
Headers show
Series Add RISC-V support | expand

Commit Message

Alexander Graf Feb. 12, 2019, 10:31 a.m. UTC
This patch adds awareness of RISC-V relocations throughout the grub tools
as well as dynamic linkage and elf->PE relocation conversion support.

Signed-off-by: Alexander Graf <agraf@suse.de>


---

v2 -> v3:

  - Fix riscv32 target

v3 -> v4:

  - Change copyright from 2013 to 2018
  - Add spec reference

v4 -> v5:

  - Add spec link to mkimagexx.c
  - Remove curly braces
---
 grub-core/kern/dl.c         |   6 +-
 grub-core/kern/riscv/dl.c   | 340 ++++++++++++++++++++++++++++++++++++++++++++
 include/grub/dl.h           |   6 +-
 util/grub-mkimagexx.c       | 259 +++++++++++++++++++++++++++++++++
 util/grub-module-verifier.c |  56 ++++++++
 5 files changed, 662 insertions(+), 5 deletions(-)
 create mode 100644 grub-core/kern/riscv/dl.c

-- 
2.12.3


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Comments

Alistair Francis Feb. 13, 2019, 12:44 a.m. UTC | #1
On Tue, 2019-02-12 at 11:31 +0100, Alexander Graf wrote:
> This patch adds awareness of RISC-V relocations throughout the grub

> tools

> as well as dynamic linkage and elf->PE relocation conversion support.

> 

> Signed-off-by: Alexander Graf <agraf@suse.de>


Reviewed-by: Alistair Francis <alistair.francis@wdc.com>


Alistair

> 

> ---

> 

> v2 -> v3:

> 

>   - Fix riscv32 target

> 

> v3 -> v4:

> 

>   - Change copyright from 2013 to 2018

>   - Add spec reference

> 

> v4 -> v5:

> 

>   - Add spec link to mkimagexx.c

>   - Remove curly braces

> ---

>  grub-core/kern/dl.c         |   6 +-

>  grub-core/kern/riscv/dl.c   | 340

> ++++++++++++++++++++++++++++++++++++++++++++

>  include/grub/dl.h           |   6 +-

>  util/grub-mkimagexx.c       | 259 +++++++++++++++++++++++++++++++++

>  util/grub-module-verifier.c |  56 ++++++++

>  5 files changed, 662 insertions(+), 5 deletions(-)

>  create mode 100644 grub-core/kern/riscv/dl.c

> 

> diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c

> index f8d58f029..48eb5e7b6 100644

> --- a/grub-core/kern/dl.c

> +++ b/grub-core/kern/dl.c

> @@ -225,7 +225,7 @@ grub_dl_load_segments (grub_dl_t mod, const

> Elf_Ehdr *e)

>    unsigned i;

>    const Elf_Shdr *s;

>    grub_size_t tsize = 0, talign = 1;

> -#if !defined (__i386__) && !defined (__x86_64__)

> +#if !defined (__i386__) && !defined (__x86_64__) &&

> !defined(__riscv)

>    grub_size_t tramp;

>    grub_size_t got;

>    grub_err_t err;

> @@ -241,7 +241,7 @@ grub_dl_load_segments (grub_dl_t mod, const

> Elf_Ehdr *e)

>  	talign = s->sh_addralign;

>      }

>  

> -#if !defined (__i386__) && !defined (__x86_64__)

> +#if !defined (__i386__) && !defined (__x86_64__) &&

> !defined(__riscv)

>    err = grub_arch_dl_get_tramp_got_size (e, &tramp, &got);

>    if (err)

>      return err;

> @@ -304,7 +304,7 @@ grub_dl_load_segments (grub_dl_t mod, const

> Elf_Ehdr *e)

>  	  mod->segment = seg;

>  	}

>      }

> -#if !defined (__i386__) && !defined (__x86_64__)

> +#if !defined (__i386__) && !defined (__x86_64__) &&

> !defined(__riscv)

>    ptr = (char *) ALIGN_UP ((grub_addr_t) ptr,

> GRUB_ARCH_DL_TRAMP_ALIGN);

>    mod->tramp = ptr;

>    mod->trampptr = ptr;

> diff --git a/grub-core/kern/riscv/dl.c b/grub-core/kern/riscv/dl.c

> new file mode 100644

> index 000000000..6fb8385ef

> --- /dev/null

> +++ b/grub-core/kern/riscv/dl.c

> @@ -0,0 +1,340 @@

> +/* dl.c - arch-dependent part of loadable module support */

> +/*

> + *  GRUB  --  GRand Unified Bootloader

> + *  Copyright (C) 2018  Free Software Foundation, Inc.

> + *

> + *  GRUB is free software: you can redistribute it and/or modify

> + *  it under the terms of the GNU General Public License as

> published by

> + *  the Free Software Foundation, either version 3 of the License,

> or

> + *  (at your option) any later version.

> + *

> + *  GRUB is distributed in the hope that it will be useful,

> + *  but WITHOUT ANY WARRANTY; without even the implied warranty of

> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

> + *  GNU General Public License for more details.

> + *

> + *  You should have received a copy of the GNU General Public

> License

> + *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>;.

> + */

> +

> +#include <grub/dl.h>

> +#include <grub/elf.h>

> +#include <grub/misc.h>

> +#include <grub/err.h>

> +#include <grub/mm.h>

> +#include <grub/i18n.h>

> +

> +/*

> + * Instructions and instruction encoding are documented in the RISC-

> V

> + * specification. This file is based on version 2.2:

> + *

> + * 

> https://github.com/riscv/riscv-isa-manual/blob/master/release/riscv-spec-v2.2.pdf

> + */

> +#define LDR 0x58000050

> +#define BR 0xd61f0200

> +

> +/*

> + * Check if EHDR is a valid ELF header.

> + */

> +grub_err_t

> +grub_arch_dl_check_header (void *ehdr)

> +{

> +  Elf_Ehdr *e = ehdr;

> +

> +  /* Check the magic numbers.  */

> +  if (e->e_ident[EI_DATA] != ELFDATA2LSB || e->e_machine !=

> EM_RISCV)

> +    return grub_error (GRUB_ERR_BAD_OS,

> +		       N_("invalid arch-dependent ELF magic"));

> +

> +  return GRUB_ERR_NONE;

> +}

> +

> +#pragma GCC diagnostic ignored "-Wcast-align"

> +

> +/* Relocate symbols. */

> +grub_err_t

> +grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,

> +			       Elf_Shdr *s, grub_dl_segment_t seg)

> +{

> +  Elf_Rel *rel, *max;

> +

> +  for (rel = (Elf_Rel *) ((char *) ehdr + s->sh_offset),

> +	 max = (Elf_Rel *) ((char *) rel + s->sh_size);

> +       rel < max;

> +       rel = (Elf_Rel *) ((char *) rel + s->sh_entsize))

> +    {

> +      Elf_Sym *sym;

> +      void *place;

> +      grub_size_t sym_addr;

> +

> +      if (rel->r_offset >= seg->size)

> +	return grub_error (GRUB_ERR_BAD_MODULE,

> +			   "reloc offset is out of the segment");

> +

> +      sym = (Elf_Sym *) ((char *) mod->symtab

> +			 + mod->symsize * ELF_R_SYM (rel->r_info));

> +

> +      sym_addr = sym->st_value;

> +      if (s->sh_type == SHT_RELA)

> +	sym_addr += ((Elf_Rela *) rel)->r_addend;

> +

> +      place = (void *) ((grub_addr_t) seg->addr + rel->r_offset);

> +

> +      switch (ELF_R_TYPE (rel->r_info))

> +	{

> +	case R_RISCV_32:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +

> +	    grub_dprintf ("dl", "  reloc_abs32 %p => 0x%016llx\n",

> +			  place, (unsigned long long) sym_addr);

> +

> +	    *abs_place = (grub_uint32_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_64:

> +	  {

> +	    grub_size_t *abs_place = place;

> +

> +	    grub_dprintf ("dl", "  reloc_abs64 %p => 0x%016llx\n",

> +			  place, (unsigned long long) sym_addr);

> +

> +	    *abs_place = (grub_size_t) sym_addr;

> +	  }

> +	  break;

> +

> +	case R_RISCV_ADD8:

> +	  {

> +	    grub_uint8_t *abs_place = place;

> +

> +	    *abs_place += (grub_uint8_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_ADD16:

> +	  {

> +	    grub_uint16_t *abs_place = place;

> +

> +	    *abs_place += (grub_uint16_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_ADD32:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +

> +	    *abs_place += (grub_uint32_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_ADD64:

> +	  {

> +	    grub_size_t *abs_place = place;

> +

> +	    *abs_place += (grub_size_t) sym_addr;

> +	  }

> +	  break;

> +

> +	case R_RISCV_SUB8:

> +	  {

> +	    grub_uint8_t *abs_place = place;

> +

> +	    *abs_place -= (grub_uint8_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_SUB16:

> +	  {

> +	    grub_uint16_t *abs_place = place;

> +

> +	    *abs_place -= (grub_uint16_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_SUB32:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +

> +	    *abs_place -= (grub_uint32_t) sym_addr;

> +	  }

> +	  break;

> +	case R_RISCV_SUB64:

> +	  {

> +	    grub_size_t *abs_place = place;

> +

> +	    *abs_place -= (grub_size_t) sym_addr;

> +	  }

> +	  break;

> +

> +	case R_RISCV_BRANCH:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;

> +	    grub_uint32_t imm12 = (off & 0x1000) << (31 - 12);

> +	    grub_uint32_t imm11 = (off & 0x800) >> (11 - 7);

> +	    grub_uint32_t imm10_5 = (off & 0x7e0) << (30 - 10);

> +	    grub_uint32_t imm4_1 = (off & 0x1e) << (11 - 4);

> +	    *abs_place = (*abs_place & 0x1fff07f)

> +			 | imm12 | imm11 | imm10_5 | imm4_1;

> +	  }

> +	  break;

> +

> +	case R_RISCV_JAL:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;

> +	    grub_uint32_t imm20 = (off & 0x100000) << (31 - 20);

> +	    grub_uint32_t imm19_12 = (off & 0xff000);

> +	    grub_uint32_t imm11 = (off & 0x800) << (20 - 11);

> +	    grub_uint32_t imm10_1 = (off & 0x7fe) << (30 - 10);

> +	    *abs_place = (*abs_place & 0xfff)

> +			 | imm20 | imm19_12 | imm11 | imm10_1;

> +	  }

> +	  break;

> +

> +	case R_RISCV_CALL:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;

> +	    grub_uint32_t hi20, lo12;

> +

> +	    if (off != (grub_int32_t) off)

> +	      return grub_error (GRUB_ERR_BAD_MODULE, "relocation

> overflow");

> +

> +	    hi20 = (off + 0x800) & 0xfffff000;

> +	    lo12 = (off - hi20) & 0xfff;

> +	    abs_place[0] = (abs_place[0] & 0xfff) | hi20;

> +	    abs_place[1] = (abs_place[1] & 0xfffff) | (lo12 << 20);

> +	  }

> +	  break;

> +

> +	case R_RISCV_RVC_BRANCH:

> +	  {

> +	    grub_uint16_t *abs_place = place;

> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;

> +	    grub_uint16_t imm8 = (off & 0x100) << (12 - 8);

> +	    grub_uint16_t imm7_6 = (off & 0xc0) >> (6 - 5);

> +	    grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);

> +	    grub_uint16_t imm4_3 = (off & 0x18) << (12 - 5);

> +	    grub_uint16_t imm2_1 = (off & 0x6) << (12 - 10);

> +	    *abs_place = (*abs_place & 0xe383)

> +			 | imm8 | imm7_6 | imm5 | imm4_3 | imm2_1;

> +	  }

> +	  break;

> +

> +	case R_RISCV_RVC_JUMP:

> +	  {

> +	    grub_uint16_t *abs_place = place;

> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;

> +	    grub_uint16_t imm11 = (off & 0x800) << (12 - 11);

> +	    grub_uint16_t imm10 = (off & 0x400) >> (10 - 8);

> +	    grub_uint16_t imm9_8 = (off & 0x300) << (12 - 11);

> +	    grub_uint16_t imm7 = (off & 0x80) >> (7 - 6);

> +	    grub_uint16_t imm6 = (off & 0x40) << (12 - 11);

> +	    grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);

> +	    grub_uint16_t imm4 = (off & 0x10) << (12 - 5);

> +	    grub_uint16_t imm3_1 = (off & 0xe) << (12 - 10);

> +	    *abs_place = ((*abs_place & 0xe003)

> +			  | imm11 | imm10 | imm9_8 | imm7 | imm6

> +			  | imm5 | imm4 | imm3_1);

> +	  }

> +	  break;

> +

> +	case R_RISCV_PCREL_HI20:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    grub_ssize_t off = sym_addr - (grub_addr_t) place;

> +	    grub_int32_t hi20;

> +

> +	    if (off != (grub_int32_t)off)

> +	      return grub_error (GRUB_ERR_BAD_MODULE, "relocation

> overflow");

> +

> +	    hi20 = (off + 0x800) & 0xfffff000;

> +	    *abs_place = (*abs_place & 0xfff) | hi20;

> +	  }

> +	break;

> +

> +	case R_RISCV_PCREL_LO12_I:

> +	case R_RISCV_PCREL_LO12_S:

> +	  {

> +	    grub_uint32_t *t32 = place;

> +	    Elf_Rela *rel2;

> +	    /* Search backwards for matching HI20 reloc.  */

> +	    for (rel2 = (Elf_Rela *) ((char *) rel - s->sh_entsize);

> +		    (unsigned long)rel2 >= ((unsigned long)ehdr + s-

> >sh_offset);

> +		    rel2 = (Elf_Rela *) ((char *) rel2 - s-

> >sh_entsize))

> +	      {

> +		Elf_Addr rel2_info;

> +		Elf_Addr rel2_offset;

> +		Elf_Addr rel2_sym_addr;

> +		Elf_Addr rel2_loc;

> +		grub_ssize_t rel2_off;

> +		grub_ssize_t off;

> +		Elf_Sym *sym2;

> +

> +		rel2_offset = rel2->r_offset;

> +		rel2_info = rel2->r_info;

> +		rel2_loc = (grub_addr_t) seg->addr + rel2_offset;

> +

> +		if (ELF_R_TYPE (rel2_info) == R_RISCV_PCREL_HI20

> +		    && rel2_loc == sym_addr)

> +		  {

> +		    sym2 = (Elf_Sym *) ((char *) mod->symtab

> +				+ mod->symsize * ELF_R_SYM (rel2-

> >r_info));

> +		    rel2_sym_addr = sym2->st_value;

> +		    if (s->sh_type == SHT_RELA)

> +		      rel2_sym_addr += ((Elf_Rela *) rel2)->r_addend;

> +

> +		    rel2_off = rel2_sym_addr - rel2_loc;

> +		    off = rel2_off - ((rel2_off + 0x800) & 0xfffff000);

> +

> +		    if (ELF_R_TYPE (rel->r_info) ==

> R_RISCV_PCREL_LO12_I)

> +		      *t32 = (*t32 & 0xfffff) | (off & 0xfff) << 20;

> +		    else

> +		      {

> +			grub_uint32_t imm11_5 = (off & 0xfe0) << (31 -

> 11);

> +			grub_uint32_t imm4_0 = (off & 0x1f) << (11 -

> 4);

> +			*t32 = (*t32 & 0x1fff07f) | imm11_5 | imm4_0;

> +		      }

> +		    break;

> +		  }

> +	      }

> +	    if ((unsigned long)rel2 < ((unsigned long)ehdr + s-

> >sh_offset))

> +	      return grub_error (GRUB_ERR_BAD_MODULE, "cannot find

> matching HI20 relocation");

> +	  }

> +	  break;

> +

> +	case R_RISCV_HI20:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    *abs_place = (*abs_place & 0xfff) |

> +			 (((grub_int32_t) sym_addr + 0x800) &

> 0xfffff000);

> +	  }

> +	  break;

> +

> +	case R_RISCV_LO12_I:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    grub_int32_t lo12 = (grub_int32_t) sym_addr -

> +				(((grub_int32_t) sym_addr + 0x800) &

> 0xfffff000);

> +	    *abs_place = (*abs_place & 0xfffff) | ((lo12 & 0xfff) <<

> 20);

> +	  }

> +	  break;

> +

> +	case R_RISCV_LO12_S:

> +	  {

> +	    grub_uint32_t *abs_place = place;

> +	    grub_int32_t lo12 = (grub_int32_t) sym_addr -

> +				(((grub_int32_t) sym_addr + 0x800) &

> 0xfffff000);

> +	    grub_uint32_t imm11_5 = (lo12 & 0xfe0) << (31 - 11);

> +	    grub_uint32_t imm4_0 = (lo12 & 0x1f) << (11 - 4);

> +	    *abs_place = (*abs_place & 0x1fff07f) | imm11_5 | imm4_0;

> +	  }

> +	  break;

> +

> +	case R_RISCV_RELAX:

> +	  break;

> +	default:

> +	  return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,

> +			     N_("relocation 0x%x is not implemented

> yet"),

> +			     ELF_R_TYPE (rel->r_info));

> +	}

> +    }

> +

> +  return GRUB_ERR_NONE;

> +}

> diff --git a/include/grub/dl.h b/include/grub/dl.h

> index fee27a14c..f03c03561 100644

> --- a/include/grub/dl.h

> +++ b/include/grub/dl.h

> @@ -292,12 +292,14 @@ grub_arch_dl_get_tramp_got_size (const void

> *ehdr, grub_size_t *tramp,

>  				 grub_size_t *got);

>  #endif

>  

> -#if defined (__powerpc__) || defined (__mips__) || defined (__arm__)

> +#if defined (__powerpc__) || defined (__mips__) || defined (__arm__)

> || \

> +    (defined(__riscv) && (__riscv_xlen == 32))

>  #define GRUB_ARCH_DL_TRAMP_ALIGN 4

>  #define GRUB_ARCH_DL_GOT_ALIGN 4

>  #endif

>  

> -#if defined (__aarch64__) || defined (__sparc__)

> +#if defined (__aarch64__) || defined (__sparc__) || \

> +    (defined(__riscv) && (__riscv_xlen == 64))

>  #define GRUB_ARCH_DL_TRAMP_ALIGN 8

>  #define GRUB_ARCH_DL_GOT_ALIGN 8

>  #endif

> diff --git a/util/grub-mkimagexx.c b/util/grub-mkimagexx.c

> index e94a721b4..c04f17d4e 100644

> --- a/util/grub-mkimagexx.c

> +++ b/util/grub-mkimagexx.c

> @@ -1226,6 +1226,196 @@ SUFFIX (relocate_addrs) (Elf_Ehdr *e, struct

> section_metadata *smd,

>  		 break;

>  	       }

>  #endif /* MKIMAGE_ELF32 */

> +	     case EM_RISCV:

> +	       {

> +		 grub_uint64_t *t64 = (grub_uint64_t *) target;

> +		 grub_uint32_t *t32 = (grub_uint32_t *) target;

> +		 grub_uint16_t *t16 = (grub_uint16_t *) target;

> +		 grub_uint8_t *t8 = (grub_uint8_t *) target;

> +		 grub_int64_t off = (long)sym_addr -

> target_section_addr - offset

> +				    - image_target->vaddr_offset;

> +

> +		 /*

> +		  * Instructions and instruction encoding are

> documented in the RISC-V

> +		  * specification. This file is based on version 2.2:

> +		  *

> +		  * 

> https://github.com/riscv/riscv-isa-manual/blob/master/release/riscv-spec-v2.2.pdf

> +		  */

> +

> +		 sym_addr += addend;

> +

> +		 switch (ELF_R_TYPE (info))

> +		   {

> +		   case R_RISCV_ADD8:

> +		     *t8 = *t8 + sym_addr;

> +		     break;

> +		   case R_RISCV_ADD16:

> +		     *t16 = grub_host_to_target16

> (grub_target_to_host16 (*t16) + sym_addr);

> +		     break;

> +		   case R_RISCV_32:

> +		   case R_RISCV_ADD32:

> +		     *t32 = grub_host_to_target32

> (grub_target_to_host32 (*t32) + sym_addr);

> +		     break;

> +		   case R_RISCV_64:

> +		   case R_RISCV_ADD64:

> +		     *t64 = grub_host_to_target64

> (grub_target_to_host64 (*t64) + sym_addr);

> +		     break;

> +

> +		   case R_RISCV_SUB8:

> +		     *t8 = sym_addr - *t8;

> +		     break;

> +		   case R_RISCV_SUB16:

> +		     *t16 = grub_host_to_target16

> (grub_target_to_host16 (*t16) - sym_addr);

> +		     break;

> +		   case R_RISCV_SUB32:

> +		     *t32 = grub_host_to_target32

> (grub_target_to_host32 (*t32) - sym_addr);

> +		     break;

> +		   case R_RISCV_SUB64:

> +		     *t64 = grub_host_to_target64

> (grub_target_to_host64 (*t64) - sym_addr);

> +		     break;

> +		   case R_RISCV_BRANCH:

> +		     {

> +		       grub_uint32_t imm12 = (off & 0x1000) << (31 -

> 12);

> +		       grub_uint32_t imm11 = (off & 0x800) >> (11 - 7);

> +		       grub_uint32_t imm10_5 = (off & 0x7e0) << (30 -

> 10);

> +		       grub_uint32_t imm4_1 = (off & 0x1e) << (11 - 4);

> +		       *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0x1fff07f)

> +						     | imm12 | imm11 |

> imm10_5 | imm4_1);

> +		     }

> +		     break;

> +		   case R_RISCV_JAL:

> +		     {

> +		       grub_uint32_t imm20 = (off & 0x100000) << (31 -

> 20);

> +		       grub_uint32_t imm19_12 = (off & 0xff000);

> +		       grub_uint32_t imm11 = (off & 0x800) << (20 -

> 11);

> +		       grub_uint32_t imm10_1 = (off & 0x7fe) << (30 -

> 10);

> +		       *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0xfff)

> +						     | imm20 | imm19_12

> | imm11 | imm10_1);

> +		     }

> +		     break;

> +		   case R_RISCV_CALL:

> +		     {

> +		       grub_uint32_t hi20, lo12;

> +

> +		       if (off != (grub_int32_t)off)

> +			 grub_util_error ("target %lx not reachable

> from pc=%lx", (long)sym_addr, (long)target);

> +

> +		       hi20 = (off + 0x800) & 0xfffff000;

> +		       lo12 = (off - hi20) & 0xfff;

> +		       t32[0] = grub_host_to_target32

> ((grub_target_to_host32 (t32[0]) & 0xfff) | hi20);

> +		       t32[1] = grub_host_to_target32

> ((grub_target_to_host32 (t32[1]) & 0xfffff) | (lo12 << 20));

> +		     }

> +		     break;

> +		   case R_RISCV_RVC_BRANCH:

> +		     {

> +		       grub_uint16_t imm8 = (off & 0x100) << (12 - 8);

> +		       grub_uint16_t imm7_6 = (off & 0xc0) >> (6 - 5);

> +		       grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);

> +		       grub_uint16_t imm4_3 = (off & 0x18) << (12 - 5);

> +		       grub_uint16_t imm2_1 = (off & 0x6) << (12 - 10);

> +		       *t16 = grub_host_to_target16

> ((grub_target_to_host16 (*t16) & 0xe383)

> +						     | imm8 | imm7_6 |

> imm5 | imm4_3 | imm2_1);

> +		     }

> +		     break;

> +		   case R_RISCV_RVC_JUMP:

> +		     {

> +		       grub_uint16_t imm11 = (off & 0x800) << (12 -

> 11);

> +		       grub_uint16_t imm10 = (off & 0x400) >> (10 - 8);

> +		       grub_uint16_t imm9_8 = (off & 0x300) << (12 -

> 11);

> +		       grub_uint16_t imm7 = (off & 0x80) >> (7 - 6);

> +		       grub_uint16_t imm6 = (off & 0x40) << (12 - 11);

> +		       grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);

> +		       grub_uint16_t imm4 = (off & 0x10) << (12 - 5);

> +		       grub_uint16_t imm3_1 = (off & 0xe) << (12 - 10);

> +		       *t16 = grub_host_to_target16

> ((grub_target_to_host16 (*t16) & 0xe003)

> +						     | imm11 | imm10 |

> imm9_8 | imm7 | imm6

> +						     | imm5 | imm4 |

> imm3_1);

> +		     }

> +		     break;

> +		   case R_RISCV_PCREL_HI20:

> +		     {

> +		       grub_int32_t hi20;

> +

> +		       if (off != (grub_int32_t)off)

> +			 grub_util_error ("target %lx not reachable

> from pc=%lx", (long)sym_addr, (long)target);

> +

> +		       hi20 = (off + 0x800) & 0xfffff000;

> +		       *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0xfff) | hi20);

> +		     }

> +		     break;

> +		   case R_RISCV_PCREL_LO12_I:

> +		   case R_RISCV_PCREL_LO12_S:

> +		     {

> +		       Elf_Rela *rel2;

> +		       Elf_Word k;

> +		       /* Search backwards for matching HI20 reloc.  */

> +		       for (k = j, rel2 = (Elf_Rela *) ((char *) r -

> r_size);

> +			    k > 0;

> +			    k--, rel2 = (Elf_Rela *) ((char *) rel2 -

> r_size))

> +			 {

> +			   Elf_Addr rel2_info;

> +			   Elf_Addr rel2_offset;

> +			   Elf_Addr rel2_sym_addr;

> +			   Elf_Addr rel2_addend;

> +			   Elf_Addr rel2_loc;

> +			   grub_int64_t rel2_off;

> +

> +			   rel2_offset = grub_target_to_host (rel2-

> >r_offset);

> +			   rel2_info = grub_target_to_host (rel2-

> >r_info);

> +			   rel2_loc = target_section_addr + rel2_offset

> + image_target->vaddr_offset;

> +

> +			   if (ELF_R_TYPE (rel2_info) ==

> R_RISCV_PCREL_HI20

> +			       && rel2_loc == sym_addr)

> +			     {

> +			       rel2_sym_addr = SUFFIX

> (get_symbol_address)

> +				 (e, smd->symtab, ELF_R_SYM

> (rel2_info),

> +				  image_target);

> +			       rel2_addend = (s->sh_type ==

> grub_target_to_host32 (SHT_RELA)) ?

> +				 grub_target_to_host (rel2->r_addend) :

> 0;

> +			       rel2_off = rel2_sym_addr + rel2_addend -

> rel2_loc;

> +			       off = rel2_off - ((rel2_off + 0x800) &

> 0xfffff000);

> +

> +			       if (ELF_R_TYPE (info) ==

> R_RISCV_PCREL_LO12_I)

> +				 *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0xfffff) | (off & 0xfff) << 20);

> +			       else

> +				 {

> +				   grub_uint32_t imm11_5 = (off &

> 0xfe0) << (31 - 11);

> +				   grub_uint32_t imm4_0 = (off & 0x1f)

> << (11 - 4);

> +				   *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0x1fff07f) | imm11_5 | imm4_0);

> +				 }

> +			       break;

> +			     }

> +			 }

> +		       if (k == 0)

> +			 grub_util_error ("cannot find matching HI20

> relocation");

> +		     }

> +		     break;

> +		   case R_RISCV_HI20:

> +		     *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0xfff) | (((grub_int32_t) sym_addr +

> 0x800) & 0xfffff000));

> +		     break;

> +		   case R_RISCV_LO12_I:

> +		     {

> +		       grub_int32_t lo12 = (grub_int32_t) sym_addr -

> (((grub_int32_t) sym_addr + 0x800) & 0xfffff000);

> +		       *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0xfffff) | ((lo12 & 0xfff) << 20));

> +		     }

> +		     break;

> +		   case R_RISCV_LO12_S:

> +		     {

> +		       grub_int32_t lo12 = (grub_int32_t) sym_addr -

> (((grub_int32_t) sym_addr + 0x800) & 0xfffff000);

> +		       grub_uint32_t imm11_5 = (lo12 & 0xfe0) << (31 -

> 11);

> +		       grub_uint32_t imm4_0 = (lo12 & 0x1f) << (11 -

> 4);

> +		       *t32 = grub_host_to_target32

> ((grub_target_to_host32 (*t32) & 0x1fff07f) | imm11_5 | imm4_0);

> +		     }

> +		     break;

> +		   case R_RISCV_RELAX:

> +		     break;

> +		   default:

> +		     grub_util_error (_("relocation 0x%x is not

> implemented yet"),

> +				      (unsigned int) ELF_R_TYPE

> (info));

> +		     break;

> +		   }

> +	       break;

> +	       }

>  	     default:

>  	       grub_util_error ("unknown architecture type %d",

>  				image_target->elf_target);

> @@ -1510,6 +1700,75 @@ translate_relocation_pe (struct

> translate_context *ctx,

>  	}

>        break;

>  #endif /* defined(MKIMAGE_ELF32) */

> +    case EM_RISCV:

> +      switch (ELF_R_TYPE (info))

> +	{

> +	case R_RISCV_32:

> +	  {

> +	    ctx->current_address

> +	      = add_fixup_entry (&ctx->lst,

> +				 GRUB_PE32_REL_BASED_HIGHLOW,

> +				 addr, 0, ctx->current_address,

> +				 image_target);

> +	  }

> +	  break;

> +	case R_RISCV_64:

> +	  {

> +	    ctx->current_address

> +	      = add_fixup_entry (&ctx->lst,

> +				 GRUB_PE32_REL_BASED_DIR64,

> +				 addr, 0, ctx->current_address,

> +				 image_target);

> +	  }

> +	  break;

> +	  /* Relative relocations do not require fixup entries. */

> +	case R_RISCV_BRANCH:

> +	case R_RISCV_JAL:

> +	case R_RISCV_CALL:

> +	case R_RISCV_PCREL_HI20:

> +	case R_RISCV_PCREL_LO12_I:

> +	case R_RISCV_PCREL_LO12_S:

> +	case R_RISCV_RVC_BRANCH:

> +	case R_RISCV_RVC_JUMP:

> +	case R_RISCV_ADD32:

> +	case R_RISCV_SUB32:

> +	  grub_util_info ("  %s:  not adding fixup: 0x%08x : 0x%08x",

> __FUNCTION__, (unsigned int) addr, (unsigned int) ctx-

> >current_address);

> +	  break;

> +	case R_RISCV_HI20:

> +	  {

> +	    ctx->current_address

> +	      = add_fixup_entry (&ctx->lst,

> +				 GRUB_PE32_REL_BASED_RISCV_HI20,

> +				 addr, 0, ctx->current_address,

> +				 image_target);

> +	  }

> +	  break;

> +	case R_RISCV_LO12_I:

> +	  {

> +	    ctx->current_address

> +	      = add_fixup_entry (&ctx->lst,

> +				 GRUB_PE32_REL_BASED_RISCV_LOW12I,

> +				 addr, 0, ctx->current_address,

> +				 image_target);

> +	  }

> +	  break;

> +	case R_RISCV_LO12_S:

> +	  {

> +	    ctx->current_address

> +	      = add_fixup_entry (&ctx->lst,

> +				 GRUB_PE32_REL_BASED_RISCV_LOW12S,

> +				 addr, 0, ctx->current_address,

> +				 image_target);

> +	  }

> +	  break;

> +	case R_RISCV_RELAX:

> +	  break;

> +	default:

> +	  grub_util_error (_("relocation 0x%x is not implemented yet"),

> +			   (unsigned int) ELF_R_TYPE (info));

> +	  break;

> +	}

> +      break;

>      default:

>        grub_util_error ("unknown machine type 0x%x", image_target-

> >elf_target);

>      }

> diff --git a/util/grub-module-verifier.c b/util/grub-module-

> verifier.c

> index 979999cb9..60e4d2c06 100644

> --- a/util/grub-module-verifier.c

> +++ b/util/grub-module-verifier.c

> @@ -117,6 +117,62 @@ struct grub_module_verifier_arch archs[] = {

>        R_AARCH64_LDST64_ABS_LO12_NC,

>        R_AARCH64_PREL32,

>        -1

> +    } },

> +  { "riscv32", 4, 0, EM_RISCV, GRUB_MODULE_VERIFY_SUPPORTS_REL |

> GRUB_MODULE_VERIFY_SUPPORTS_RELA, (int[]){

> +      R_RISCV_32,

> +      R_RISCV_64,

> +      R_RISCV_ADD8,

> +      R_RISCV_ADD16,

> +      R_RISCV_ADD32,

> +      R_RISCV_ADD64,

> +      R_RISCV_SUB8,

> +      R_RISCV_SUB16,

> +      R_RISCV_SUB32,

> +      R_RISCV_SUB64,

> +      R_RISCV_ALIGN,

> +      R_RISCV_BRANCH,

> +      R_RISCV_CALL,

> +      R_RISCV_CALL_PLT,

> +      R_RISCV_GOT_HI20,

> +      R_RISCV_HI20,

> +      R_RISCV_JAL,

> +      R_RISCV_LO12_I,

> +      R_RISCV_LO12_S,

> +      R_RISCV_PCREL_HI20,

> +      R_RISCV_PCREL_LO12_I,

> +      R_RISCV_PCREL_LO12_S,

> +      R_RISCV_RELAX,

> +      R_RISCV_RVC_BRANCH,

> +      R_RISCV_RVC_JUMP,

> +      -1

> +    } },

> +  { "riscv64", 8, 0, EM_RISCV, GRUB_MODULE_VERIFY_SUPPORTS_REL |

> GRUB_MODULE_VERIFY_SUPPORTS_RELA, (int[]){

> +      R_RISCV_32,

> +      R_RISCV_64,

> +      R_RISCV_ADD8,

> +      R_RISCV_ADD16,

> +      R_RISCV_ADD32,

> +      R_RISCV_ADD64,

> +      R_RISCV_SUB8,

> +      R_RISCV_SUB16,

> +      R_RISCV_SUB32,

> +      R_RISCV_SUB64,

> +      R_RISCV_ALIGN,

> +      R_RISCV_BRANCH,

> +      R_RISCV_CALL,

> +      R_RISCV_CALL_PLT,

> +      R_RISCV_GOT_HI20,

> +      R_RISCV_HI20,

> +      R_RISCV_JAL,

> +      R_RISCV_LO12_I,

> +      R_RISCV_LO12_S,

> +      R_RISCV_PCREL_HI20,

> +      R_RISCV_PCREL_LO12_I,

> +      R_RISCV_PCREL_LO12_S,

> +      R_RISCV_RELAX,

> +      R_RISCV_RVC_BRANCH,

> +      R_RISCV_RVC_JUMP,

> +      -1

>      }

>    },

>  };

_______________________________________________
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
Daniel Kiper Feb. 18, 2019, 7:36 p.m. UTC | #2
On Wed, Feb 13, 2019 at 12:44:32AM +0000, Alistair Francis wrote:
> On Tue, 2019-02-12 at 11:31 +0100, Alexander Graf wrote:

> > This patch adds awareness of RISC-V relocations throughout the grub

> > tools

> > as well as dynamic linkage and elf->PE relocation conversion support.

> >

> > Signed-off-by: Alexander Graf <agraf@suse.de>

>

> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>


Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>


Daniel

_______________________________________________
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
diff mbox series

Patch

diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c
index f8d58f029..48eb5e7b6 100644
--- a/grub-core/kern/dl.c
+++ b/grub-core/kern/dl.c
@@ -225,7 +225,7 @@  grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e)
   unsigned i;
   const Elf_Shdr *s;
   grub_size_t tsize = 0, talign = 1;
-#if !defined (__i386__) && !defined (__x86_64__)
+#if !defined (__i386__) && !defined (__x86_64__) && !defined(__riscv)
   grub_size_t tramp;
   grub_size_t got;
   grub_err_t err;
@@ -241,7 +241,7 @@  grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e)
 	talign = s->sh_addralign;
     }
 
-#if !defined (__i386__) && !defined (__x86_64__)
+#if !defined (__i386__) && !defined (__x86_64__) && !defined(__riscv)
   err = grub_arch_dl_get_tramp_got_size (e, &tramp, &got);
   if (err)
     return err;
@@ -304,7 +304,7 @@  grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e)
 	  mod->segment = seg;
 	}
     }
-#if !defined (__i386__) && !defined (__x86_64__)
+#if !defined (__i386__) && !defined (__x86_64__) && !defined(__riscv)
   ptr = (char *) ALIGN_UP ((grub_addr_t) ptr, GRUB_ARCH_DL_TRAMP_ALIGN);
   mod->tramp = ptr;
   mod->trampptr = ptr;
diff --git a/grub-core/kern/riscv/dl.c b/grub-core/kern/riscv/dl.c
new file mode 100644
index 000000000..6fb8385ef
--- /dev/null
+++ b/grub-core/kern/riscv/dl.c
@@ -0,0 +1,340 @@ 
+/* dl.c - arch-dependent part of loadable module support */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2018  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/dl.h>
+#include <grub/elf.h>
+#include <grub/misc.h>
+#include <grub/err.h>
+#include <grub/mm.h>
+#include <grub/i18n.h>
+
+/*
+ * Instructions and instruction encoding are documented in the RISC-V
+ * specification. This file is based on version 2.2:
+ *
+ * https://github.com/riscv/riscv-isa-manual/blob/master/release/riscv-spec-v2.2.pdf
+ */
+#define LDR 0x58000050
+#define BR 0xd61f0200
+
+/*
+ * Check if EHDR is a valid ELF header.
+ */
+grub_err_t
+grub_arch_dl_check_header (void *ehdr)
+{
+  Elf_Ehdr *e = ehdr;
+
+  /* Check the magic numbers.  */
+  if (e->e_ident[EI_DATA] != ELFDATA2LSB || e->e_machine != EM_RISCV)
+    return grub_error (GRUB_ERR_BAD_OS,
+		       N_("invalid arch-dependent ELF magic"));
+
+  return GRUB_ERR_NONE;
+}
+
+#pragma GCC diagnostic ignored "-Wcast-align"
+
+/* Relocate symbols. */
+grub_err_t
+grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
+			       Elf_Shdr *s, grub_dl_segment_t seg)
+{
+  Elf_Rel *rel, *max;
+
+  for (rel = (Elf_Rel *) ((char *) ehdr + s->sh_offset),
+	 max = (Elf_Rel *) ((char *) rel + s->sh_size);
+       rel < max;
+       rel = (Elf_Rel *) ((char *) rel + s->sh_entsize))
+    {
+      Elf_Sym *sym;
+      void *place;
+      grub_size_t sym_addr;
+
+      if (rel->r_offset >= seg->size)
+	return grub_error (GRUB_ERR_BAD_MODULE,
+			   "reloc offset is out of the segment");
+
+      sym = (Elf_Sym *) ((char *) mod->symtab
+			 + mod->symsize * ELF_R_SYM (rel->r_info));
+
+      sym_addr = sym->st_value;
+      if (s->sh_type == SHT_RELA)
+	sym_addr += ((Elf_Rela *) rel)->r_addend;
+
+      place = (void *) ((grub_addr_t) seg->addr + rel->r_offset);
+
+      switch (ELF_R_TYPE (rel->r_info))
+	{
+	case R_RISCV_32:
+	  {
+	    grub_uint32_t *abs_place = place;
+
+	    grub_dprintf ("dl", "  reloc_abs32 %p => 0x%016llx\n",
+			  place, (unsigned long long) sym_addr);
+
+	    *abs_place = (grub_uint32_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_64:
+	  {
+	    grub_size_t *abs_place = place;
+
+	    grub_dprintf ("dl", "  reloc_abs64 %p => 0x%016llx\n",
+			  place, (unsigned long long) sym_addr);
+
+	    *abs_place = (grub_size_t) sym_addr;
+	  }
+	  break;
+
+	case R_RISCV_ADD8:
+	  {
+	    grub_uint8_t *abs_place = place;
+
+	    *abs_place += (grub_uint8_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_ADD16:
+	  {
+	    grub_uint16_t *abs_place = place;
+
+	    *abs_place += (grub_uint16_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_ADD32:
+	  {
+	    grub_uint32_t *abs_place = place;
+
+	    *abs_place += (grub_uint32_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_ADD64:
+	  {
+	    grub_size_t *abs_place = place;
+
+	    *abs_place += (grub_size_t) sym_addr;
+	  }
+	  break;
+
+	case R_RISCV_SUB8:
+	  {
+	    grub_uint8_t *abs_place = place;
+
+	    *abs_place -= (grub_uint8_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_SUB16:
+	  {
+	    grub_uint16_t *abs_place = place;
+
+	    *abs_place -= (grub_uint16_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_SUB32:
+	  {
+	    grub_uint32_t *abs_place = place;
+
+	    *abs_place -= (grub_uint32_t) sym_addr;
+	  }
+	  break;
+	case R_RISCV_SUB64:
+	  {
+	    grub_size_t *abs_place = place;
+
+	    *abs_place -= (grub_size_t) sym_addr;
+	  }
+	  break;
+
+	case R_RISCV_BRANCH:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
+	    grub_uint32_t imm12 = (off & 0x1000) << (31 - 12);
+	    grub_uint32_t imm11 = (off & 0x800) >> (11 - 7);
+	    grub_uint32_t imm10_5 = (off & 0x7e0) << (30 - 10);
+	    grub_uint32_t imm4_1 = (off & 0x1e) << (11 - 4);
+	    *abs_place = (*abs_place & 0x1fff07f)
+			 | imm12 | imm11 | imm10_5 | imm4_1;
+	  }
+	  break;
+
+	case R_RISCV_JAL:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
+	    grub_uint32_t imm20 = (off & 0x100000) << (31 - 20);
+	    grub_uint32_t imm19_12 = (off & 0xff000);
+	    grub_uint32_t imm11 = (off & 0x800) << (20 - 11);
+	    grub_uint32_t imm10_1 = (off & 0x7fe) << (30 - 10);
+	    *abs_place = (*abs_place & 0xfff)
+			 | imm20 | imm19_12 | imm11 | imm10_1;
+	  }
+	  break;
+
+	case R_RISCV_CALL:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
+	    grub_uint32_t hi20, lo12;
+
+	    if (off != (grub_int32_t) off)
+	      return grub_error (GRUB_ERR_BAD_MODULE, "relocation overflow");
+
+	    hi20 = (off + 0x800) & 0xfffff000;
+	    lo12 = (off - hi20) & 0xfff;
+	    abs_place[0] = (abs_place[0] & 0xfff) | hi20;
+	    abs_place[1] = (abs_place[1] & 0xfffff) | (lo12 << 20);
+	  }
+	  break;
+
+	case R_RISCV_RVC_BRANCH:
+	  {
+	    grub_uint16_t *abs_place = place;
+	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
+	    grub_uint16_t imm8 = (off & 0x100) << (12 - 8);
+	    grub_uint16_t imm7_6 = (off & 0xc0) >> (6 - 5);
+	    grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);
+	    grub_uint16_t imm4_3 = (off & 0x18) << (12 - 5);
+	    grub_uint16_t imm2_1 = (off & 0x6) << (12 - 10);
+	    *abs_place = (*abs_place & 0xe383)
+			 | imm8 | imm7_6 | imm5 | imm4_3 | imm2_1;
+	  }
+	  break;
+
+	case R_RISCV_RVC_JUMP:
+	  {
+	    grub_uint16_t *abs_place = place;
+	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
+	    grub_uint16_t imm11 = (off & 0x800) << (12 - 11);
+	    grub_uint16_t imm10 = (off & 0x400) >> (10 - 8);
+	    grub_uint16_t imm9_8 = (off & 0x300) << (12 - 11);
+	    grub_uint16_t imm7 = (off & 0x80) >> (7 - 6);
+	    grub_uint16_t imm6 = (off & 0x40) << (12 - 11);
+	    grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);
+	    grub_uint16_t imm4 = (off & 0x10) << (12 - 5);
+	    grub_uint16_t imm3_1 = (off & 0xe) << (12 - 10);
+	    *abs_place = ((*abs_place & 0xe003)
+			  | imm11 | imm10 | imm9_8 | imm7 | imm6
+			  | imm5 | imm4 | imm3_1);
+	  }
+	  break;
+
+	case R_RISCV_PCREL_HI20:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    grub_ssize_t off = sym_addr - (grub_addr_t) place;
+	    grub_int32_t hi20;
+
+	    if (off != (grub_int32_t)off)
+	      return grub_error (GRUB_ERR_BAD_MODULE, "relocation overflow");
+
+	    hi20 = (off + 0x800) & 0xfffff000;
+	    *abs_place = (*abs_place & 0xfff) | hi20;
+	  }
+	break;
+
+	case R_RISCV_PCREL_LO12_I:
+	case R_RISCV_PCREL_LO12_S:
+	  {
+	    grub_uint32_t *t32 = place;
+	    Elf_Rela *rel2;
+	    /* Search backwards for matching HI20 reloc.  */
+	    for (rel2 = (Elf_Rela *) ((char *) rel - s->sh_entsize);
+		    (unsigned long)rel2 >= ((unsigned long)ehdr + s->sh_offset);
+		    rel2 = (Elf_Rela *) ((char *) rel2 - s->sh_entsize))
+	      {
+		Elf_Addr rel2_info;
+		Elf_Addr rel2_offset;
+		Elf_Addr rel2_sym_addr;
+		Elf_Addr rel2_loc;
+		grub_ssize_t rel2_off;
+		grub_ssize_t off;
+		Elf_Sym *sym2;
+
+		rel2_offset = rel2->r_offset;
+		rel2_info = rel2->r_info;
+		rel2_loc = (grub_addr_t) seg->addr + rel2_offset;
+
+		if (ELF_R_TYPE (rel2_info) == R_RISCV_PCREL_HI20
+		    && rel2_loc == sym_addr)
+		  {
+		    sym2 = (Elf_Sym *) ((char *) mod->symtab
+				+ mod->symsize * ELF_R_SYM (rel2->r_info));
+		    rel2_sym_addr = sym2->st_value;
+		    if (s->sh_type == SHT_RELA)
+		      rel2_sym_addr += ((Elf_Rela *) rel2)->r_addend;
+
+		    rel2_off = rel2_sym_addr - rel2_loc;
+		    off = rel2_off - ((rel2_off + 0x800) & 0xfffff000);
+
+		    if (ELF_R_TYPE (rel->r_info) == R_RISCV_PCREL_LO12_I)
+		      *t32 = (*t32 & 0xfffff) | (off & 0xfff) << 20;
+		    else
+		      {
+			grub_uint32_t imm11_5 = (off & 0xfe0) << (31 - 11);
+			grub_uint32_t imm4_0 = (off & 0x1f) << (11 - 4);
+			*t32 = (*t32 & 0x1fff07f) | imm11_5 | imm4_0;
+		      }
+		    break;
+		  }
+	      }
+	    if ((unsigned long)rel2 < ((unsigned long)ehdr + s->sh_offset))
+	      return grub_error (GRUB_ERR_BAD_MODULE, "cannot find matching HI20 relocation");
+	  }
+	  break;
+
+	case R_RISCV_HI20:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    *abs_place = (*abs_place & 0xfff) |
+			 (((grub_int32_t) sym_addr + 0x800) & 0xfffff000);
+	  }
+	  break;
+
+	case R_RISCV_LO12_I:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    grub_int32_t lo12 = (grub_int32_t) sym_addr -
+				(((grub_int32_t) sym_addr + 0x800) & 0xfffff000);
+	    *abs_place = (*abs_place & 0xfffff) | ((lo12 & 0xfff) << 20);
+	  }
+	  break;
+
+	case R_RISCV_LO12_S:
+	  {
+	    grub_uint32_t *abs_place = place;
+	    grub_int32_t lo12 = (grub_int32_t) sym_addr -
+				(((grub_int32_t) sym_addr + 0x800) & 0xfffff000);
+	    grub_uint32_t imm11_5 = (lo12 & 0xfe0) << (31 - 11);
+	    grub_uint32_t imm4_0 = (lo12 & 0x1f) << (11 - 4);
+	    *abs_place = (*abs_place & 0x1fff07f) | imm11_5 | imm4_0;
+	  }
+	  break;
+
+	case R_RISCV_RELAX:
+	  break;
+	default:
+	  return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+			     N_("relocation 0x%x is not implemented yet"),
+			     ELF_R_TYPE (rel->r_info));
+	}
+    }
+
+  return GRUB_ERR_NONE;
+}
diff --git a/include/grub/dl.h b/include/grub/dl.h
index fee27a14c..f03c03561 100644
--- a/include/grub/dl.h
+++ b/include/grub/dl.h
@@ -292,12 +292,14 @@  grub_arch_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,
 				 grub_size_t *got);
 #endif
 
-#if defined (__powerpc__) || defined (__mips__) || defined (__arm__)
+#if defined (__powerpc__) || defined (__mips__) || defined (__arm__) || \
+    (defined(__riscv) && (__riscv_xlen == 32))
 #define GRUB_ARCH_DL_TRAMP_ALIGN 4
 #define GRUB_ARCH_DL_GOT_ALIGN 4
 #endif
 
-#if defined (__aarch64__) || defined (__sparc__)
+#if defined (__aarch64__) || defined (__sparc__) || \
+    (defined(__riscv) && (__riscv_xlen == 64))
 #define GRUB_ARCH_DL_TRAMP_ALIGN 8
 #define GRUB_ARCH_DL_GOT_ALIGN 8
 #endif
diff --git a/util/grub-mkimagexx.c b/util/grub-mkimagexx.c
index e94a721b4..c04f17d4e 100644
--- a/util/grub-mkimagexx.c
+++ b/util/grub-mkimagexx.c
@@ -1226,6 +1226,196 @@  SUFFIX (relocate_addrs) (Elf_Ehdr *e, struct section_metadata *smd,
 		 break;
 	       }
 #endif /* MKIMAGE_ELF32 */
+	     case EM_RISCV:
+	       {
+		 grub_uint64_t *t64 = (grub_uint64_t *) target;
+		 grub_uint32_t *t32 = (grub_uint32_t *) target;
+		 grub_uint16_t *t16 = (grub_uint16_t *) target;
+		 grub_uint8_t *t8 = (grub_uint8_t *) target;
+		 grub_int64_t off = (long)sym_addr - target_section_addr - offset
+				    - image_target->vaddr_offset;
+
+		 /*
+		  * Instructions and instruction encoding are documented in the RISC-V
+		  * specification. This file is based on version 2.2:
+		  *
+		  * https://github.com/riscv/riscv-isa-manual/blob/master/release/riscv-spec-v2.2.pdf
+		  */
+
+		 sym_addr += addend;
+
+		 switch (ELF_R_TYPE (info))
+		   {
+		   case R_RISCV_ADD8:
+		     *t8 = *t8 + sym_addr;
+		     break;
+		   case R_RISCV_ADD16:
+		     *t16 = grub_host_to_target16 (grub_target_to_host16 (*t16) + sym_addr);
+		     break;
+		   case R_RISCV_32:
+		   case R_RISCV_ADD32:
+		     *t32 = grub_host_to_target32 (grub_target_to_host32 (*t32) + sym_addr);
+		     break;
+		   case R_RISCV_64:
+		   case R_RISCV_ADD64:
+		     *t64 = grub_host_to_target64 (grub_target_to_host64 (*t64) + sym_addr);
+		     break;
+
+		   case R_RISCV_SUB8:
+		     *t8 = sym_addr - *t8;
+		     break;
+		   case R_RISCV_SUB16:
+		     *t16 = grub_host_to_target16 (grub_target_to_host16 (*t16) - sym_addr);
+		     break;
+		   case R_RISCV_SUB32:
+		     *t32 = grub_host_to_target32 (grub_target_to_host32 (*t32) - sym_addr);
+		     break;
+		   case R_RISCV_SUB64:
+		     *t64 = grub_host_to_target64 (grub_target_to_host64 (*t64) - sym_addr);
+		     break;
+		   case R_RISCV_BRANCH:
+		     {
+		       grub_uint32_t imm12 = (off & 0x1000) << (31 - 12);
+		       grub_uint32_t imm11 = (off & 0x800) >> (11 - 7);
+		       grub_uint32_t imm10_5 = (off & 0x7e0) << (30 - 10);
+		       grub_uint32_t imm4_1 = (off & 0x1e) << (11 - 4);
+		       *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0x1fff07f)
+						     | imm12 | imm11 | imm10_5 | imm4_1);
+		     }
+		     break;
+		   case R_RISCV_JAL:
+		     {
+		       grub_uint32_t imm20 = (off & 0x100000) << (31 - 20);
+		       grub_uint32_t imm19_12 = (off & 0xff000);
+		       grub_uint32_t imm11 = (off & 0x800) << (20 - 11);
+		       grub_uint32_t imm10_1 = (off & 0x7fe) << (30 - 10);
+		       *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0xfff)
+						     | imm20 | imm19_12 | imm11 | imm10_1);
+		     }
+		     break;
+		   case R_RISCV_CALL:
+		     {
+		       grub_uint32_t hi20, lo12;
+
+		       if (off != (grub_int32_t)off)
+			 grub_util_error ("target %lx not reachable from pc=%lx", (long)sym_addr, (long)target);
+
+		       hi20 = (off + 0x800) & 0xfffff000;
+		       lo12 = (off - hi20) & 0xfff;
+		       t32[0] = grub_host_to_target32 ((grub_target_to_host32 (t32[0]) & 0xfff) | hi20);
+		       t32[1] = grub_host_to_target32 ((grub_target_to_host32 (t32[1]) & 0xfffff) | (lo12 << 20));
+		     }
+		     break;
+		   case R_RISCV_RVC_BRANCH:
+		     {
+		       grub_uint16_t imm8 = (off & 0x100) << (12 - 8);
+		       grub_uint16_t imm7_6 = (off & 0xc0) >> (6 - 5);
+		       grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);
+		       grub_uint16_t imm4_3 = (off & 0x18) << (12 - 5);
+		       grub_uint16_t imm2_1 = (off & 0x6) << (12 - 10);
+		       *t16 = grub_host_to_target16 ((grub_target_to_host16 (*t16) & 0xe383)
+						     | imm8 | imm7_6 | imm5 | imm4_3 | imm2_1);
+		     }
+		     break;
+		   case R_RISCV_RVC_JUMP:
+		     {
+		       grub_uint16_t imm11 = (off & 0x800) << (12 - 11);
+		       grub_uint16_t imm10 = (off & 0x400) >> (10 - 8);
+		       grub_uint16_t imm9_8 = (off & 0x300) << (12 - 11);
+		       grub_uint16_t imm7 = (off & 0x80) >> (7 - 6);
+		       grub_uint16_t imm6 = (off & 0x40) << (12 - 11);
+		       grub_uint16_t imm5 = (off & 0x20) >> (5 - 2);
+		       grub_uint16_t imm4 = (off & 0x10) << (12 - 5);
+		       grub_uint16_t imm3_1 = (off & 0xe) << (12 - 10);
+		       *t16 = grub_host_to_target16 ((grub_target_to_host16 (*t16) & 0xe003)
+						     | imm11 | imm10 | imm9_8 | imm7 | imm6
+						     | imm5 | imm4 | imm3_1);
+		     }
+		     break;
+		   case R_RISCV_PCREL_HI20:
+		     {
+		       grub_int32_t hi20;
+
+		       if (off != (grub_int32_t)off)
+			 grub_util_error ("target %lx not reachable from pc=%lx", (long)sym_addr, (long)target);
+
+		       hi20 = (off + 0x800) & 0xfffff000;
+		       *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0xfff) | hi20);
+		     }
+		     break;
+		   case R_RISCV_PCREL_LO12_I:
+		   case R_RISCV_PCREL_LO12_S:
+		     {
+		       Elf_Rela *rel2;
+		       Elf_Word k;
+		       /* Search backwards for matching HI20 reloc.  */
+		       for (k = j, rel2 = (Elf_Rela *) ((char *) r - r_size);
+			    k > 0;
+			    k--, rel2 = (Elf_Rela *) ((char *) rel2 - r_size))
+			 {
+			   Elf_Addr rel2_info;
+			   Elf_Addr rel2_offset;
+			   Elf_Addr rel2_sym_addr;
+			   Elf_Addr rel2_addend;
+			   Elf_Addr rel2_loc;
+			   grub_int64_t rel2_off;
+
+			   rel2_offset = grub_target_to_host (rel2->r_offset);
+			   rel2_info = grub_target_to_host (rel2->r_info);
+			   rel2_loc = target_section_addr + rel2_offset + image_target->vaddr_offset;
+
+			   if (ELF_R_TYPE (rel2_info) == R_RISCV_PCREL_HI20
+			       && rel2_loc == sym_addr)
+			     {
+			       rel2_sym_addr = SUFFIX (get_symbol_address)
+				 (e, smd->symtab, ELF_R_SYM (rel2_info),
+				  image_target);
+			       rel2_addend = (s->sh_type == grub_target_to_host32 (SHT_RELA)) ?
+				 grub_target_to_host (rel2->r_addend) : 0;
+			       rel2_off = rel2_sym_addr + rel2_addend - rel2_loc;
+			       off = rel2_off - ((rel2_off + 0x800) & 0xfffff000);
+
+			       if (ELF_R_TYPE (info) == R_RISCV_PCREL_LO12_I)
+				 *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0xfffff) | (off & 0xfff) << 20);
+			       else
+				 {
+				   grub_uint32_t imm11_5 = (off & 0xfe0) << (31 - 11);
+				   grub_uint32_t imm4_0 = (off & 0x1f) << (11 - 4);
+				   *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0x1fff07f) | imm11_5 | imm4_0);
+				 }
+			       break;
+			     }
+			 }
+		       if (k == 0)
+			 grub_util_error ("cannot find matching HI20 relocation");
+		     }
+		     break;
+		   case R_RISCV_HI20:
+		     *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0xfff) | (((grub_int32_t) sym_addr + 0x800) & 0xfffff000));
+		     break;
+		   case R_RISCV_LO12_I:
+		     {
+		       grub_int32_t lo12 = (grub_int32_t) sym_addr - (((grub_int32_t) sym_addr + 0x800) & 0xfffff000);
+		       *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0xfffff) | ((lo12 & 0xfff) << 20));
+		     }
+		     break;
+		   case R_RISCV_LO12_S:
+		     {
+		       grub_int32_t lo12 = (grub_int32_t) sym_addr - (((grub_int32_t) sym_addr + 0x800) & 0xfffff000);
+		       grub_uint32_t imm11_5 = (lo12 & 0xfe0) << (31 - 11);
+		       grub_uint32_t imm4_0 = (lo12 & 0x1f) << (11 - 4);
+		       *t32 = grub_host_to_target32 ((grub_target_to_host32 (*t32) & 0x1fff07f) | imm11_5 | imm4_0);
+		     }
+		     break;
+		   case R_RISCV_RELAX:
+		     break;
+		   default:
+		     grub_util_error (_("relocation 0x%x is not implemented yet"),
+				      (unsigned int) ELF_R_TYPE (info));
+		     break;
+		   }
+	       break;
+	       }
 	     default:
 	       grub_util_error ("unknown architecture type %d",
 				image_target->elf_target);
@@ -1510,6 +1700,75 @@  translate_relocation_pe (struct translate_context *ctx,
 	}
       break;
 #endif /* defined(MKIMAGE_ELF32) */
+    case EM_RISCV:
+      switch (ELF_R_TYPE (info))
+	{
+	case R_RISCV_32:
+	  {
+	    ctx->current_address
+	      = add_fixup_entry (&ctx->lst,
+				 GRUB_PE32_REL_BASED_HIGHLOW,
+				 addr, 0, ctx->current_address,
+				 image_target);
+	  }
+	  break;
+	case R_RISCV_64:
+	  {
+	    ctx->current_address
+	      = add_fixup_entry (&ctx->lst,
+				 GRUB_PE32_REL_BASED_DIR64,
+				 addr, 0, ctx->current_address,
+				 image_target);
+	  }
+	  break;
+	  /* Relative relocations do not require fixup entries. */
+	case R_RISCV_BRANCH:
+	case R_RISCV_JAL:
+	case R_RISCV_CALL:
+	case R_RISCV_PCREL_HI20:
+	case R_RISCV_PCREL_LO12_I:
+	case R_RISCV_PCREL_LO12_S:
+	case R_RISCV_RVC_BRANCH:
+	case R_RISCV_RVC_JUMP:
+	case R_RISCV_ADD32:
+	case R_RISCV_SUB32:
+	  grub_util_info ("  %s:  not adding fixup: 0x%08x : 0x%08x", __FUNCTION__, (unsigned int) addr, (unsigned int) ctx->current_address);
+	  break;
+	case R_RISCV_HI20:
+	  {
+	    ctx->current_address
+	      = add_fixup_entry (&ctx->lst,
+				 GRUB_PE32_REL_BASED_RISCV_HI20,
+				 addr, 0, ctx->current_address,
+				 image_target);
+	  }
+	  break;
+	case R_RISCV_LO12_I:
+	  {
+	    ctx->current_address
+	      = add_fixup_entry (&ctx->lst,
+				 GRUB_PE32_REL_BASED_RISCV_LOW12I,
+				 addr, 0, ctx->current_address,
+				 image_target);
+	  }
+	  break;
+	case R_RISCV_LO12_S:
+	  {
+	    ctx->current_address
+	      = add_fixup_entry (&ctx->lst,
+				 GRUB_PE32_REL_BASED_RISCV_LOW12S,
+				 addr, 0, ctx->current_address,
+				 image_target);
+	  }
+	  break;
+	case R_RISCV_RELAX:
+	  break;
+	default:
+	  grub_util_error (_("relocation 0x%x is not implemented yet"),
+			   (unsigned int) ELF_R_TYPE (info));
+	  break;
+	}
+      break;
     default:
       grub_util_error ("unknown machine type 0x%x", image_target->elf_target);
     }
diff --git a/util/grub-module-verifier.c b/util/grub-module-verifier.c
index 979999cb9..60e4d2c06 100644
--- a/util/grub-module-verifier.c
+++ b/util/grub-module-verifier.c
@@ -117,6 +117,62 @@  struct grub_module_verifier_arch archs[] = {
       R_AARCH64_LDST64_ABS_LO12_NC,
       R_AARCH64_PREL32,
       -1
+    } },
+  { "riscv32", 4, 0, EM_RISCV, GRUB_MODULE_VERIFY_SUPPORTS_REL | GRUB_MODULE_VERIFY_SUPPORTS_RELA, (int[]){
+      R_RISCV_32,
+      R_RISCV_64,
+      R_RISCV_ADD8,
+      R_RISCV_ADD16,
+      R_RISCV_ADD32,
+      R_RISCV_ADD64,
+      R_RISCV_SUB8,
+      R_RISCV_SUB16,
+      R_RISCV_SUB32,
+      R_RISCV_SUB64,
+      R_RISCV_ALIGN,
+      R_RISCV_BRANCH,
+      R_RISCV_CALL,
+      R_RISCV_CALL_PLT,
+      R_RISCV_GOT_HI20,
+      R_RISCV_HI20,
+      R_RISCV_JAL,
+      R_RISCV_LO12_I,
+      R_RISCV_LO12_S,
+      R_RISCV_PCREL_HI20,
+      R_RISCV_PCREL_LO12_I,
+      R_RISCV_PCREL_LO12_S,
+      R_RISCV_RELAX,
+      R_RISCV_RVC_BRANCH,
+      R_RISCV_RVC_JUMP,
+      -1
+    } },
+  { "riscv64", 8, 0, EM_RISCV, GRUB_MODULE_VERIFY_SUPPORTS_REL | GRUB_MODULE_VERIFY_SUPPORTS_RELA, (int[]){
+      R_RISCV_32,
+      R_RISCV_64,
+      R_RISCV_ADD8,
+      R_RISCV_ADD16,
+      R_RISCV_ADD32,
+      R_RISCV_ADD64,
+      R_RISCV_SUB8,
+      R_RISCV_SUB16,
+      R_RISCV_SUB32,
+      R_RISCV_SUB64,
+      R_RISCV_ALIGN,
+      R_RISCV_BRANCH,
+      R_RISCV_CALL,
+      R_RISCV_CALL_PLT,
+      R_RISCV_GOT_HI20,
+      R_RISCV_HI20,
+      R_RISCV_JAL,
+      R_RISCV_LO12_I,
+      R_RISCV_LO12_S,
+      R_RISCV_PCREL_HI20,
+      R_RISCV_PCREL_LO12_I,
+      R_RISCV_PCREL_LO12_S,
+      R_RISCV_RELAX,
+      R_RISCV_RVC_BRANCH,
+      R_RISCV_RVC_JUMP,
+      -1
     }
   },
 };