Index: ELF/Arch/RISCV.cpp
===================================================================
--- ELF/Arch/RISCV.cpp
+++ ELF/Arch/RISCV.cpp
@@ -20,6 +20,8 @@
 using namespace lld;
 using namespace lld::elf;
 
+static constexpr uint64_t TLS_DTP_OFFSET = 0x800;
+
 namespace {
 
 class RISCV final : public TargetInfo {
@@ -57,6 +59,15 @@
   GotHeaderEntriesNum = 1;
   GotPltHeaderEntriesNum = 2;
   GotBaseSymInGotPlt = false;
+  if (Config->Is64) {
+    TlsGotRel = R_RISCV_TLS_TPREL64;
+    TlsModuleIndexRel = R_RISCV_TLS_DTPMOD64;
+    TlsOffsetRel = R_RISCV_TLS_DTPREL64;
+  } else {
+    TlsGotRel = R_RISCV_TLS_TPREL32;
+    TlsModuleIndexRel = R_RISCV_TLS_DTPMOD32;
+    TlsOffsetRel = R_RISCV_TLS_DTPREL32;
+  }
 }
 
 static uint32_t getEFlags(InputFile *F) {
@@ -176,9 +187,17 @@
   case R_RISCV_PCREL_LO12_S:
     return R_RISCV_PC_INDIRECT;
   case R_RISCV_GOT_HI20:
+  case R_RISCV_TLS_GOT_HI20:
     return R_GOT_PC;
+  case R_RISCV_TPREL_HI20:
+  case R_RISCV_TPREL_LO12_I:
+  case R_RISCV_TPREL_LO12_S:
+    return R_TLS;
+  case R_RISCV_TLS_GD_HI20:
+    return R_TLSGD_PC;
   case R_RISCV_ALIGN:
   case R_RISCV_RELAX:
+  case R_RISCV_TPREL_ADD:
     return R_HINT;
   default:
     return R_ABS;
@@ -288,7 +307,10 @@
   }
 
   case R_RISCV_PCREL_HI20:
+  case R_RISCV_TPREL_HI20:
   case R_RISCV_GOT_HI20:
+  case R_RISCV_TLS_GOT_HI20:
+  case R_RISCV_TLS_GD_HI20:
   case R_RISCV_HI20: {
     checkInt(Loc, Val, 32, Type);
     uint32_t Hi = Val + 0x800;
@@ -297,6 +319,7 @@
   }
 
   case R_RISCV_PCREL_LO12_I:
+  case R_RISCV_TPREL_LO12_I:
   case R_RISCV_LO12_I: {
     checkInt(Loc, Val, 32, Type);
     uint32_t Hi = Val + 0x800;
@@ -306,6 +329,7 @@
   }
 
   case R_RISCV_PCREL_LO12_S:
+  case R_RISCV_TPREL_LO12_S:
   case R_RISCV_LO12_S: {
     checkInt(Loc, Val, 32, Type);
     uint32_t Hi = Val + 0x800;
@@ -316,6 +340,27 @@
     return;
   }
 
+  case R_RISCV_TLS_DTPMOD32:
+    write32le(Loc, 1);
+    return;
+  case R_RISCV_TLS_DTPMOD64:
+    write64le(Loc, 1);
+    return;
+  case R_RISCV_TLS_DTPREL32:
+    write32le(Loc, Val - TLS_DTP_OFFSET);
+    return;
+  case R_RISCV_TLS_DTPREL64:
+    write64le(Loc, Val - TLS_DTP_OFFSET);
+    return;
+  case R_RISCV_TLS_TPREL32:
+    write32le(Loc, Val);
+    return;
+  case R_RISCV_TLS_TPREL64:
+    write64le(Loc, Val);
+    return;
+  case R_RISCV_TPREL_ADD:
+    return; // Do nothing
+
   case R_RISCV_ADD8:
     *Loc += Val;
     return;
Index: ELF/InputSection.cpp
===================================================================
--- ELF/InputSection.cpp
+++ ELF/InputSection.cpp
@@ -500,7 +500,7 @@
   auto Range = std::equal_range(IS->Relocations.begin(), IS->Relocations.end(),
                                 D->Value, RelocationOffsetComparator{});
   for (auto It = std::get<0>(Range); It != std::get<1>(Range); ++It)
-    if (isRelExprOneOf<R_PC, R_PLT_PC, R_GOT_PC>(It->Expr))
+    if (isRelExprOneOf<R_PC, R_PLT_PC, R_GOT_PC, R_TLSGD_PC>(It->Expr))
       return &*It;
 
   error("R_RISCV_PCREL_LO12 relocation points to " + IS->getObjMsg(D->Value) +
@@ -661,7 +661,8 @@
     // For TLS variant 1 the TCB is a fixed size, whereas for TLS variant 2 the
     // TCB is on unspecified size and content. Targets that implement variant 1
     // should set TcbSize.
-    if (Target->TcbSize) {
+    // RISC-V uses variant I but tp points to the end of TCB.
+    if (Target->TcbSize || Config->EMachine == EM_RISCV) {
       // PPC64 V2 ABI has the thread pointer offset into the middle of the TLS
       // storage area by TlsTpOffset for efficient addressing TCB and up to
       // 4KB – 8 B of other thread library information (placed before the TCB).
Index: ELF/Relocations.cpp
===================================================================
--- ELF/Relocations.cpp
+++ ELF/Relocations.cpp
@@ -171,7 +171,9 @@
   if (!Sym.isTls())
     return 0;
 
-  if (Config->EMachine == EM_ARM)
+  // TODO: RISC-V currently doesn't implement TLS relaxation yet, so we reuse
+  // the same logic for ARM tls relocation.
+  if (Config->EMachine == EM_ARM || Config->EMachine == EM_RISCV)
     return handleARMTlsRelocation<ELFT>(Type, Sym, C, Offset, Addend, Expr);
   if (Config->EMachine == EM_MIPS)
     return handleMipsTlsRelocation(Type, Sym, C, Offset, Addend, Expr);
Index: test/ELF/Inputs/riscv-shared.yaml
===================================================================
--- test/ELF/Inputs/riscv-shared.yaml
+++ test/ELF/Inputs/riscv-shared.yaml
@@ -20,6 +20,11 @@
     Type:            SHT_NOBITS
     Flags:           [ SHF_WRITE, SHF_ALLOC ]
     AddressAlign:    0x0000000000000001
+  - Name:            .tdata
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC, SHF_TLS ]
+    AddressAlign:    0x0000000000000001
+    Content:         2A000000
 Symbols:         
   Local:           
     - Name:            .text
@@ -31,12 +36,22 @@
     - Name:            .bss
       Type:            STT_SECTION
       Section:         .bss
+    - Name:            .tdata
+      Type:            STT_SECTION
+      Section:         .tdata
   Global:          
     - Name:            f
       Type:            STT_FUNC
       Section:         .text
+    - Name:            __tls_get_addr
+      Type:            STT_FUNC
+      Section:         .text
     - Name:            x
       Type:            STT_OBJECT
       Section:         .data
       Size:            0x0000000000000004
+    - Name:            tx
+      Type:            STT_TLS
+      Section:         .tdata
+      Size:            0x0000000000000004
 ...
Index: test/ELF/riscv-tls-gd.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-tls-gd.test
@@ -0,0 +1,96 @@
+# .option norelax
+# .option pic
+#
+# .global _start
+# _start:
+# L1:
+#     la.tls.gd   a0, tx
+#     call        __tls_get_addr@plt
+#     lw          a0, 0(a0)
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: yaml2obj %p/Inputs/riscv-shared.yaml -o %t2.o
+# RUN: ld.lld -shared %t2.o -o %t3.so
+# RUN: ld.lld %t.o %t3.so -o %t --section-start .got=0x20000 --section-start .text=0x10000 -z norelro
+# RUN: obj2yaml %t | FileCheck %s
+#
+# CHECK: - Name:            .text
+# CHECK:   Content:         '170501001305050097200100E78080010841'
+# 10000:       00010517                auipc   a0,0x10
+# 10004:       00050513                mv      a0,a0
+# 10008:       00012097                auipc   ra,0x12
+# 1000c:       018080e7                jalr    24(ra) # 22020 <__tls_get_addr@plt>
+# 10010:       4108                    lw      a0,0(a0)
+#
+# CHECK: - Name:            .got
+# CHECK:   Content:         '0000000000000000'
+# CHECK: - Name:            .rela.dyn
+# CHECK:   Relocations:
+# CHECK:     - Offset:          0x0000000000020000
+# CHECK:       Symbol:          tx
+# CHECK:       Type:            R_RISCV_TLS_DTPMOD32
+# CHECK:     - Offset:          0x0000000000020004
+# CHECK:       Symbol:          tx
+# CHECK:       Type:            R_RISCV_TLS_DTPREL32
+
+--- !ELF
+FileHeader:
+  Class:           ELFCLASS32
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_RISCV
+  Flags:           [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x0000000000000002
+    Content:         '170500001305050097000000E78000000841'
+  - Name:            .rela.text
+    Type:            SHT_RELA
+    Flags:           [ SHF_INFO_LINK ]
+    Link:            .symtab
+    AddressAlign:    0x0000000000000004
+    Info:            .text
+    Relocations:
+      - Offset:          0x0000000000000000
+        Symbol:          tx
+        Type:            R_RISCV_TLS_GD_HI20
+      - Offset:          0x0000000000000004
+        Symbol:          '.L0 '
+        Type:            R_RISCV_PCREL_LO12_I
+      - Offset:          0x0000000000000008
+        Symbol:          __tls_get_addr
+        Type:            R_RISCV_CALL_PLT
+  - Name:            .data
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+    Content:         ''
+  - Name:            .bss
+    Type:            SHT_NOBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+Symbols:
+  Local:
+    - Name:            .text
+      Type:            STT_SECTION
+      Section:         .text
+    - Name:            .data
+      Type:            STT_SECTION
+      Section:         .data
+    - Name:            .bss
+      Type:            STT_SECTION
+      Section:         .bss
+    - Name:            L1
+      Section:         .text
+    - Name:            '.L0 '
+      Section:         .text
+  Global:
+    - Name:            _start
+      Section:         .text
+    - Name:            tx
+      Type:            STT_TLS
+    - Name:            __tls_get_addr
+...
Index: test/ELF/riscv-tls-ie.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-tls-ie.test
@@ -0,0 +1,87 @@
+# .option norelax
+# .option pic
+# .global _start
+# _start:
+# L1:
+#     la.tls.ie   a5, tx
+#     add         a5, a5, tp
+#     lw          a5, 0(a5)
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: yaml2obj %p/Inputs/riscv-shared.yaml -o %t2.o
+# RUN: ld.lld -shared %t2.o -o %t3.so
+# RUN: ld.lld %t.o %t3.so -o %t --section-start .got=0x20000 --section-start .text=0x10000 -z norelro
+# RUN: obj2yaml %t | FileCheck %s
+#
+# CHECK: - Name:            .text
+# CHECK:   Content:         9707010083A7070092979C43
+# 10000:       00010797                auipc   a5,0x10
+# 10004:       0007a783                lw      a5,0(a5) # 20000 <_start+0x10000>
+# 10008:       9792                    add     a5,a5,tp
+# 1000a:       439c                    lw      a5,0(a5)
+#
+# CHECK: - Name:            .got
+# CHECK:   Content:         '00000000'
+# CHECK: - Name:            .rela.dyn
+# CHECK:   Relocations:
+# CHECK:     - Offset:          0x0000000000020000
+# CHECK:       Symbol:          tx
+# CHECK:       Type:            R_RISCV_TLS_TPREL32
+
+--- !ELF
+FileHeader:
+  Class:           ELFCLASS32
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_RISCV
+  Flags:           [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x0000000000000002
+    Content:         9707000083A7070092979C43
+  - Name:            .rela.text
+    Type:            SHT_RELA
+    Flags:           [ SHF_INFO_LINK ]
+    Link:            .symtab
+    AddressAlign:    0x0000000000000004
+    Info:            .text
+    Relocations:
+      - Offset:          0x0000000000000000
+        Symbol:          tx
+        Type:            R_RISCV_TLS_GOT_HI20
+      - Offset:          0x0000000000000004
+        Symbol:          '.L0 '
+        Type:            R_RISCV_PCREL_LO12_I
+  - Name:            .data
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+    Content:         ''
+  - Name:            .bss
+    Type:            SHT_NOBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+Symbols:
+  Local:
+    - Name:            .text
+      Type:            STT_SECTION
+      Section:         .text
+    - Name:            .data
+      Type:            STT_SECTION
+      Section:         .data
+    - Name:            .bss
+      Type:            STT_SECTION
+      Section:         .bss
+    - Name:            L1
+      Section:         .text
+    - Name:            '.L0 '
+      Section:         .text
+  Global:
+    - Name:            _start
+      Section:         .text
+    - Name:            tx
+      Type:            STT_TLS
+...
Index: test/ELF/riscv-tls-le.test
===================================================================
--- /dev/null
+++ test/ELF/riscv-tls-le.test
@@ -0,0 +1,96 @@
+# .option norelax
+# .global _start
+# _start:
+# L1:
+#     lui a5, %tprel_hi(x)
+#     add a5, a5, tp, %tprel_add(x)
+#     lw  a5, %tprel_lo(x)(a5)
+#
+# .section    .tdata, "awT", @progbits
+# .type       x, @object
+# .size       x, 4
+# x:
+#     .word 42
+#
+#
+# REQUIRES: riscv
+# RUN: yaml2obj %s -o %t.o
+# RUN: ld.lld %t.o -o %t
+# RUN: obj2yaml %t | FileCheck %s
+#
+# CHECK: - Name:            .text
+# CHECK:   Content:         B7070000B387470083A70700
+# 11000:       000007b7                lui     a5,0x0
+# 11004:       004787b3                add     a5,a5,tp
+# 11008:       0007a783                lw      a5,0(a5) # 0 <x>
+#
+# CHECK: - Name:            .tdata
+# CHECK:   Content:         2A000000
+
+--- !ELF
+FileHeader:
+  Class:           ELFCLASS32
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_RISCV
+  Flags:           [ EF_RISCV_RVC, EF_RISCV_FLOAT_ABI_SOFT ]
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    AddressAlign:    0x0000000000000002
+    Content:         B7070000B387470083A70700
+  - Name:            .rela.text
+    Type:            SHT_RELA
+    Flags:           [ SHF_INFO_LINK ]
+    Link:            .symtab
+    AddressAlign:    0x0000000000000004
+    Info:            .text
+    Relocations:
+      - Offset:          0x0000000000000000
+        Symbol:          x
+        Type:            R_RISCV_TPREL_HI20
+      - Offset:          0x0000000000000004
+        Symbol:          x
+        Type:            R_RISCV_TPREL_ADD
+      - Offset:          0x0000000000000008
+        Symbol:          x
+        Type:            R_RISCV_TPREL_LO12_I
+  - Name:            .data
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+    Content:         ''
+  - Name:            .bss
+    Type:            SHT_NOBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC ]
+    AddressAlign:    0x0000000000000001
+  - Name:            .tdata
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_WRITE, SHF_ALLOC, SHF_TLS ]
+    AddressAlign:    0x0000000000000001
+    Content:         2A000000
+Symbols:
+  Local:
+    - Name:            .text
+      Type:            STT_SECTION
+      Section:         .text
+    - Name:            .data
+      Type:            STT_SECTION
+      Section:         .data
+    - Name:            .bss
+      Type:            STT_SECTION
+      Section:         .bss
+    - Name:            L1
+      Section:         .text
+    - Name:            x
+      Type:            STT_TLS
+      Section:         .tdata
+      Size:            0x0000000000000004
+    - Name:            .tdata
+      Type:            STT_SECTION
+      Section:         .tdata
+  Global:
+    - Name:            _start
+      Section:         .text
+...