From abfff7c45d43360ebd292dc26b6542094c145f5f Mon Sep 17 00:00:00 2001 From: Sunil V L Date: Thu, 24 Jun 2021 21:25:31 +0800 Subject: [PATCH 1/1] BaseTools GenFw: Add support for RISCV GOT/PLT relocations Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3096 This patch adds support for R_RISCV_CALL_PLT and R_RISCV_GOT_HI20 relocations generated by PIE enabled compiler. This also needed changes to R_RISCV_32 and R_RISCV_64 relocations as explained in https://github.com/riscv/riscv-gnu-toolchain/issues/905#issuecomment-846682710 Testing: 1) Debian GCC 8.3.0 and booted sifive_u and QMEU virt models. 2) Debian 10.2.0 and booted QEMU virt model. 3) riscv-gnu-tool chain 9.2 and booted QEMU virt model. Signed-off-by: Sunil V L Acked-by: Abner Chang Reviewed-by: Daniel Schaefer Tested-by: Daniel Schaefer Reviewed-by: Liming Gao Cc: Bob Feng Cc: Liming Gao Cc: Yuwei Chen Cc: Heinrich Schuchardt --- BaseTools/Source/C/GenFw/Elf64Convert.c | 59 ++++++++++++++++++++++--- 1 file changed, 53 insertions(+), 6 deletions(-) diff --git a/BaseTools/Source/C/GenFw/Elf64Convert.c b/BaseTools/Source/C/GenFw/Elf64Convert.c index 33031ec8f6..3d7e20aaff 100644 --- a/BaseTools/Source/C/GenFw/Elf64Convert.c +++ b/BaseTools/Source/C/GenFw/Elf64Convert.c @@ -129,6 +129,8 @@ STATIC UINT32 mDebugOffset; STATIC UINT8 *mRiscVPass1Targ = NULL; STATIC Elf_Shdr *mRiscVPass1Sym = NULL; STATIC Elf64_Half mRiscVPass1SymSecIndex = 0; +STATIC INT32 mRiscVPass1Offset; +STATIC INT32 mRiscVPass1GotFixup; // // Initialization Function @@ -474,17 +476,18 @@ WriteSectionRiscV64 ( { UINT32 Value; UINT32 Value2; + Elf64_Addr GOTEntryRva; switch (ELF_R_TYPE(Rel->r_info)) { case R_RISCV_NONE: break; case R_RISCV_32: - *(UINT32 *)Targ = (UINT32)((UINT64)(*(UINT32 *)Targ) - SymShdr->sh_addr + mCoffSectionsOffset[Sym->st_shndx]); + *(UINT64 *)Targ = Sym->st_value + Rel->r_addend; break; case R_RISCV_64: - *(UINT64 *)Targ = *(UINT64 *)Targ - SymShdr->sh_addr + mCoffSectionsOffset[Sym->st_shndx]; + *(UINT64 *)Targ = Sym->st_value + Rel->r_addend; break; case R_RISCV_HI20: @@ -534,6 +537,18 @@ WriteSectionRiscV64 ( mRiscVPass1SymSecIndex = 0; break; + case R_RISCV_GOT_HI20: + GOTEntryRva = (Sym->st_value - Rel->r_offset); + mRiscVPass1Offset = RV_X(GOTEntryRva, 0, 12); + Value = (UINT32)RV_X(GOTEntryRva, 12, 20); + *(UINT32 *)Targ = (Value << 12) | (RV_X(*(UINT32*)Targ, 0, 12)); + + mRiscVPass1Targ = Targ; + mRiscVPass1Sym = SymShdr; + mRiscVPass1SymSecIndex = Sym->st_shndx; + mRiscVPass1GotFixup = 1; + break; + case R_RISCV_PCREL_HI20: mRiscVPass1Targ = Targ; mRiscVPass1Sym = SymShdr; @@ -546,11 +561,17 @@ WriteSectionRiscV64 ( if (mRiscVPass1Targ != NULL && mRiscVPass1Sym != NULL && mRiscVPass1SymSecIndex != 0) { int i; Value2 = (UINT32)(RV_X(*(UINT32 *)mRiscVPass1Targ, 12, 20)); - Value = (UINT32)(RV_X(*(UINT32 *)Targ, 20, 12)); - if(Value & (RISCV_IMM_REACH/2)) { - Value |= ~(RISCV_IMM_REACH-1); + + if(mRiscVPass1GotFixup) { + Value = (UINT32)(mRiscVPass1Offset); + } else { + Value = (UINT32)(RV_X(*(UINT32 *)Targ, 20, 12)); + if(Value & (RISCV_IMM_REACH/2)) { + Value |= ~(RISCV_IMM_REACH-1); + } } Value = Value - (UINT32)mRiscVPass1Sym->sh_addr + mCoffSectionsOffset[mRiscVPass1SymSecIndex]; + if(-2048 > (INT32)Value) { i = (((INT32)Value * -1) / 4096); Value2 -= i; @@ -570,12 +591,35 @@ WriteSectionRiscV64 ( } } - *(UINT32 *)Targ = (RV_X(Value, 0, 12) << 20) | (RV_X(*(UINT32*)Targ, 0, 20)); + if(mRiscVPass1GotFixup) { + *(UINT32 *)Targ = (RV_X((UINT32)Value, 0, 12) << 20) + | (RV_X(*(UINT32*)Targ, 0, 20)); + // Convert LD instruction to ADDI + // + // |31 20|19 15|14 12|11 7|6 0| + // |-----------------------------------------| + // |imm[11:0] | rs1 | 011 | rd | 0000011 | LD + // ----------------------------------------- + + // |-----------------------------------------| + // |imm[11:0] | rs1 | 000 | rd | 0010011 | ADDI + // ----------------------------------------- + + // To convert, let's first reset bits 12-14 and 0-6 using ~0x707f + // Then modify the opcode to ADDI (0010011) + // All other fields will remain same. + + *(UINT32 *)Targ = ((*(UINT32 *)Targ & ~0x707f) | 0x13); + } else { + *(UINT32 *)Targ = (RV_X(Value, 0, 12) << 20) | (RV_X(*(UINT32*)Targ, 0, 20)); + } *(UINT32 *)mRiscVPass1Targ = (RV_X(Value2, 0, 20)<<12) | (RV_X(*(UINT32 *)mRiscVPass1Targ, 0, 12)); } mRiscVPass1Sym = NULL; mRiscVPass1Targ = NULL; mRiscVPass1SymSecIndex = 0; + mRiscVPass1Offset = 0; + mRiscVPass1GotFixup = 0; break; case R_RISCV_ADD64: @@ -587,6 +631,7 @@ WriteSectionRiscV64 ( case R_RISCV_GPREL_I: case R_RISCV_GPREL_S: case R_RISCV_CALL: + case R_RISCV_CALL_PLT: case R_RISCV_RVC_BRANCH: case R_RISCV_RVC_JUMP: case R_RISCV_RELAX: @@ -1530,6 +1575,7 @@ WriteRelocations64 ( case R_RISCV_GPREL_I: case R_RISCV_GPREL_S: case R_RISCV_CALL: + case R_RISCV_CALL_PLT: case R_RISCV_RVC_BRANCH: case R_RISCV_RVC_JUMP: case R_RISCV_RELAX: @@ -1539,6 +1585,7 @@ WriteRelocations64 ( case R_RISCV_SET16: case R_RISCV_SET32: case R_RISCV_PCREL_HI20: + case R_RISCV_GOT_HI20: case R_RISCV_PCREL_LO12_I: break; -- 2.39.2