diff --git a/disas/meson.build b/disas/meson.build
index e0ee326411..8f64e378f9 100644
--- a/disas/meson.build
+++ b/disas/meson.build
@@ -8,6 +8,7 @@ common_ss.add(when: 'CONFIG_MIPS_DIS', if_true: files('mips.c', 'nanomips.c'))
 common_ss.add(when: 'CONFIG_NIOS2_DIS', if_true: files('nios2.c'))
 common_ss.add(when: 'CONFIG_RISCV_DIS', if_true: files(
     'riscv.c',
+    'riscv-xthead.c',
     'riscv-xventana.c'
 ))
 common_ss.add(when: 'CONFIG_SH4_DIS', if_true: files('sh4.c'))
diff --git a/disas/riscv-xthead.c b/disas/riscv-xthead.c
new file mode 100644
index 0000000000..99da679d16
--- /dev/null
+++ b/disas/riscv-xthead.c
@@ -0,0 +1,707 @@
+/*
+ * QEMU RISC-V Disassembler for xthead.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "disas/riscv.h"
+#include "disas/riscv-xthead.h"
+
+typedef enum {
+    /* 0 is reserved for rv_op_illegal. */
+    /* XTheadBa */
+    rv_op_th_addsl = 1,
+    /* XTheadBb */
+    rv_op_th_srri,
+    rv_op_th_srriw,
+    rv_op_th_ext,
+    rv_op_th_extu,
+    rv_op_th_ff0,
+    rv_op_th_ff1,
+    rv_op_th_rev,
+    rv_op_th_revw,
+    rv_op_th_tstnbz,
+    /* XTheadBs */
+    rv_op_th_tst,
+    /* XTheadCmo */
+    rv_op_th_dcache_call,
+    rv_op_th_dcache_ciall,
+    rv_op_th_dcache_iall,
+    rv_op_th_dcache_cpa,
+    rv_op_th_dcache_cipa,
+    rv_op_th_dcache_ipa,
+    rv_op_th_dcache_cva,
+    rv_op_th_dcache_civa,
+    rv_op_th_dcache_iva,
+    rv_op_th_dcache_csw,
+    rv_op_th_dcache_cisw,
+    rv_op_th_dcache_isw,
+    rv_op_th_dcache_cpal1,
+    rv_op_th_dcache_cval1,
+    rv_op_th_icache_iall,
+    rv_op_th_icache_ialls,
+    rv_op_th_icache_ipa,
+    rv_op_th_icache_iva,
+    rv_op_th_l2cache_call,
+    rv_op_th_l2cache_ciall,
+    rv_op_th_l2cache_iall,
+    /* XTheadCondMov */
+    rv_op_th_mveqz,
+    rv_op_th_mvnez,
+    /* XTheadFMemIdx */
+    rv_op_th_flrd,
+    rv_op_th_flrw,
+    rv_op_th_flurd,
+    rv_op_th_flurw,
+    rv_op_th_fsrd,
+    rv_op_th_fsrw,
+    rv_op_th_fsurd,
+    rv_op_th_fsurw,
+    /* XTheadFmv */
+    rv_op_th_fmv_hw_x,
+    rv_op_th_fmv_x_hw,
+    /* XTheadMac */
+    rv_op_th_mula,
+    rv_op_th_mulah,
+    rv_op_th_mulaw,
+    rv_op_th_muls,
+    rv_op_th_mulsw,
+    rv_op_th_mulsh,
+    /* XTheadMemIdx */
+    rv_op_th_lbia,
+    rv_op_th_lbib,
+    rv_op_th_lbuia,
+    rv_op_th_lbuib,
+    rv_op_th_lhia,
+    rv_op_th_lhib,
+    rv_op_th_lhuia,
+    rv_op_th_lhuib,
+    rv_op_th_lwia,
+    rv_op_th_lwib,
+    rv_op_th_lwuia,
+    rv_op_th_lwuib,
+    rv_op_th_ldia,
+    rv_op_th_ldib,
+    rv_op_th_sbia,
+    rv_op_th_sbib,
+    rv_op_th_shia,
+    rv_op_th_shib,
+    rv_op_th_swia,
+    rv_op_th_swib,
+    rv_op_th_sdia,
+    rv_op_th_sdib,
+    rv_op_th_lrb,
+    rv_op_th_lrbu,
+    rv_op_th_lrh,
+    rv_op_th_lrhu,
+    rv_op_th_lrw,
+    rv_op_th_lrwu,
+    rv_op_th_lrd,
+    rv_op_th_srb,
+    rv_op_th_srh,
+    rv_op_th_srw,
+    rv_op_th_srd,
+    rv_op_th_lurb,
+    rv_op_th_lurbu,
+    rv_op_th_lurh,
+    rv_op_th_lurhu,
+    rv_op_th_lurw,
+    rv_op_th_lurwu,
+    rv_op_th_lurd,
+    rv_op_th_surb,
+    rv_op_th_surh,
+    rv_op_th_surw,
+    rv_op_th_surd,
+    /* XTheadMemPair */
+    rv_op_th_ldd,
+    rv_op_th_lwd,
+    rv_op_th_lwud,
+    rv_op_th_sdd,
+    rv_op_th_swd,
+    /* XTheadSync */
+    rv_op_th_sfence_vmas,
+    rv_op_th_sync,
+    rv_op_th_sync_i,
+    rv_op_th_sync_is,
+    rv_op_th_sync_s,
+} rv_xthead_op;
+
+const rv_opcode_data xthead_opcode_data[] = {
+    { "th.illegal", rv_codec_illegal, rv_fmt_none, NULL, 0, 0, 0 },
+    /* XTheadBa */
+    { "th.addsl", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    /* XTheadBb */
+    { "th.srri", rv_codec_r2_imm6, rv_fmt_rd_rs1_imm, NULL, 0, 0, 0 },
+    { "th.srriw", rv_codec_r2_imm5, rv_fmt_rd_rs1_imm, NULL, 0, 0, 0 },
+    { "th.ext", rv_codec_r2_immhl, rv_fmt_rd_rs1_immh_imml, NULL, 0, 0, 0 },
+    { "th.extu", rv_codec_r2_immhl, rv_fmt_rd_rs1_immh_imml, NULL, 0, 0, 0 },
+    { "th.ff0", rv_codec_r2, rv_fmt_rd_rs1, NULL, 0, 0, 0 },
+    { "th.ff1", rv_codec_r2, rv_fmt_rd_rs1, NULL, 0, 0, 0 },
+    { "th.rev", rv_codec_r2, rv_fmt_rd_rs1, NULL, 0, 0, 0 },
+    { "th.revw", rv_codec_r2, rv_fmt_rd_rs1, NULL, 0, 0, 0 },
+    { "th.tstnbz", rv_codec_r2, rv_fmt_rd_rs1, NULL, 0, 0, 0 },
+    /* XTheadBs */
+    { "th.tst", rv_codec_r2_imm6, rv_fmt_rd_rs1_imm, NULL, 0, 0, 0 },
+    /* XTheadCmo */
+    { "th.dcache.call", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.dcache.ciall", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.dcache.iall", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.dcache.cpa", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.cipa", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.ipa", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.cva", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.civa", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.iva", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.csw", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.cisw", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.isw", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.cpal1", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.dcache.cval1", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.icache.iall", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.icache.ialls", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.icache.ipa", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.icache.iva", rv_codec_r, rv_fmt_rs1, NULL, 0, 0, 0 },
+    { "th.l2cache.call", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.l2cache.ciall", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.l2cache.iall", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    /* XTheadCondMov */
+    { "th.mveqz", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.mvnez", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    /* XTheadFMemIdx */
+    { "th.flrd", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.flrw", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.flurd", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.flurw", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.fsrd", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.fsrw", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.fsurd", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.fsurw", rv_codec_r_imm2, rv_fmt_frd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    /* XTheadFmv */
+    { "th.fmv.hw.x", rv_codec_r, rv_fmt_rd_frs1, NULL, 0, 0, 0 },
+    { "th.fmv.x.hw", rv_codec_r, rv_fmt_rd_frs1, NULL, 0, 0, 0 },
+    /* XTheadMac */
+    { "th.mula", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.mulaw", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.mulah", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.muls", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.mulsw", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.mulsh", rv_codec_r, rv_fmt_rd_rs1_rs2, NULL, 0, 0, 0 },
+    /* XTheadMemIdx */
+    { "th.lbia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lbib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml, NULL, 0, 0, 0 },
+    { "th.lbuia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lbuib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lhia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lhib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lhuia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lhuib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lwia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lwib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lwuia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lwuib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.ldia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.ldib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.sbia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.sbib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.shia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.shib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.swia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.swib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.sdia", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.sdib", rv_codec_r2_imm2_imm5, rv_fmt_rd_rs1_immh_imml_addr, NULL, 0, 0, 0 },
+    { "th.lrb", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lrbu", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lrh", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lrhu", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lrw", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lrwu", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lrd", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.srb", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.srh", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.srw", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.srd", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurb", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurbu", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurh", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurhu", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurw", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurwu", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.lurd", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.surb", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.surh", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.surw", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    { "th.surd", rv_codec_r_imm2, rv_fmt_rd_rs1_rs2_imm, NULL, 0, 0, 0 },
+    /* XTheadMemPair */
+    { "th.ldd", rv_codec_r_imm2, rv_fmt_rd2_imm, NULL, 0, 0, 0 },
+    { "th.lwd", rv_codec_r_imm2, rv_fmt_rd2_imm, NULL, 0, 0, 0 },
+    { "th.lwud", rv_codec_r_imm2, rv_fmt_rd2_imm, NULL, 0, 0, 0 },
+    { "th.sdd", rv_codec_r_imm2, rv_fmt_rd2_imm, NULL, 0, 0, 0 },
+    { "th.swd", rv_codec_r_imm2, rv_fmt_rd2_imm, NULL, 0, 0, 0 },
+    /* XTheadSync */
+    { "th.sfence.vmas", rv_codec_r, rv_fmt_rs1_rs2, NULL, 0, 0, 0 },
+    { "th.sync", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.sync.i", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.sync.is", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+    { "th.sync.s", rv_codec_none, rv_fmt_none, NULL, 0, 0, 0 },
+};
+
+void decode_xtheadba(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 1:
+                switch ((inst >> 25) & 0b1111111) {
+                case 0b0000000:
+                case 0b0000001:
+                case 0b0000010:
+                case 0b0000011: op = rv_op_th_addsl; break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadbb(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 1:
+                switch ((inst >> 25) & 0b1111111) {
+                case 0b0001010: op = rv_op_th_srriw; break;
+                case 0b1000000:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_tstnbz;
+                    }
+                    break;
+                case 0b1000001:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_rev;
+                    }
+                    break;
+                case 0b1000010:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_ff0;
+                    }
+                    break;
+                case 0b1000011:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_ff1;
+                    }
+                    break;
+                case 0b1000100:
+                case 0b1001000:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_revw;
+                    }
+                    break;
+                case 0b0000100:
+                case 0b0000101: op = rv_op_th_srri; break;
+                }
+                break;
+            case 2: op = rv_op_th_ext; break;
+            case 3: op = rv_op_th_extu; break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadbs(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 1:
+                switch ((inst >> 26) & 0b111111) {
+                case 0b100010: op = rv_op_th_tst; break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadcmo(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 0:
+                switch ((inst >> 20 & 0b111111111111)) {
+                case 0b000000000001:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_dcache_call;
+                    }
+                    break;
+                case 0b000000000011:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_dcache_ciall;
+                    }
+                    break;
+                case 0b000000000010:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_dcache_iall;
+                    }
+                    break;
+                case 0b000000101001: op = rv_op_th_dcache_cpa; break;
+                case 0b000000101011: op = rv_op_th_dcache_cipa; break;
+                case 0b000000101010: op = rv_op_th_dcache_ipa; break;
+                case 0b000000100101: op = rv_op_th_dcache_cva; break;
+                case 0b000000100111: op = rv_op_th_dcache_civa; break;
+                case 0b000000100110: op = rv_op_th_dcache_iva; break;
+                case 0b000000100001: op = rv_op_th_dcache_csw; break;
+                case 0b000000100011: op = rv_op_th_dcache_cisw; break;
+                case 0b000000100010: op = rv_op_th_dcache_isw; break;
+                case 0b000000101000: op = rv_op_th_dcache_cpal1; break;
+                case 0b000000100100: op = rv_op_th_dcache_cval1; break;
+                case 0b000000010000:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_icache_iall;
+                    }
+                    break;
+                case 0b000000010001:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_icache_ialls;
+                    }
+                    break;
+                case 0b000000111000: op = rv_op_th_icache_ipa; break;
+                case 0b000000110000: op = rv_op_th_icache_iva; break;
+                case 0b000000010101:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_l2cache_call;
+                    }
+                    break;
+                case 0b000000010111:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_l2cache_ciall;
+                    }
+                    break;
+                case 0b000000010110:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_l2cache_iall;
+                    }
+                    break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadcondmov(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 1:
+                switch ((inst >> 25) & 0b1111111) {
+                case 0b0100000: op = rv_op_th_mveqz; break;
+                case 0b0100001: op = rv_op_th_mvnez; break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadfmemidx(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 6:
+                switch ((inst >> 27) & 0b11111) {
+                case 8: op = rv_op_th_flrw; break;
+                case 10: op = rv_op_th_flurw; break;
+                case 12: op = rv_op_th_flrd; break;
+                case 14: op = rv_op_th_flurd; break;
+                }
+                break;
+            case 7:
+                switch ((inst >> 27) & 0b11111) {
+                case 8: op = rv_op_th_fsrw; break;
+                case 10: op = rv_op_th_fsurw; break;
+                case 12: op = rv_op_th_fsrd; break;
+                case 14: op = rv_op_th_fsurd; break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadfmv(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 1:
+                switch ((inst >> 25) & 0b1111111) {
+                case 0b1010000:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_fmv_hw_x;
+                    }
+                    break;
+                case 0b1100000:
+                    if (((inst >> 20) & 0b11111) == 0) {
+                        op = rv_op_th_fmv_x_hw;
+                    }
+                    break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadmac(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 1:
+                switch ((inst >> 25) & 0b1111111) {
+                case 0b0010000: op = rv_op_th_mula; break;
+                case 0b0010001: op = rv_op_th_muls; break;
+                case 0b0010010: op = rv_op_th_mulaw; break;
+                case 0b0010011: op = rv_op_th_mulsw; break;
+                case 0b0010100: op = rv_op_th_mulah; break;
+                case 0b0010101: op = rv_op_th_mulsh; break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadmemidx(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 4:
+                switch ((inst >> 27) & 0b11111) {
+                case 0: op = rv_op_th_lrb; break;
+                case 1: op = rv_op_th_lbib; break;
+                case 2: op = rv_op_th_lurb; break;
+                case 3: op = rv_op_th_lbia; break;
+                case 4: op = rv_op_th_lrh; break;
+                case 5: op = rv_op_th_lhib; break;
+                case 6: op = rv_op_th_lurh; break;
+                case 7: op = rv_op_th_lhia; break;
+                case 8: op = rv_op_th_lrw; break;
+                case 9: op = rv_op_th_lwib; break;
+                case 10: op = rv_op_th_lurw; break;
+                case 11: op = rv_op_th_lwia; break;
+                case 12: op = rv_op_th_lrd; break;
+                case 13: op = rv_op_th_ldib; break;
+                case 14: op = rv_op_th_lurd; break;
+                case 15: op = rv_op_th_ldia; break;
+                case 16: op = rv_op_th_lrbu; break;
+                case 17: op = rv_op_th_lbuib; break;
+                case 18: op = rv_op_th_lurbu; break;
+                case 19: op = rv_op_th_lbuia; break;
+                case 20: op = rv_op_th_lrhu; break;
+                case 21: op = rv_op_th_lhuib; break;
+                case 22: op = rv_op_th_lurhu; break;
+                case 23: op = rv_op_th_lhuia; break;
+                case 24: op = rv_op_th_lrwu; break;
+                case 25: op = rv_op_th_lwuib; break;
+                case 26: op = rv_op_th_lurwu; break;
+                case 27: op = rv_op_th_lwuia; break;
+                }
+                break;
+            case 5:
+                switch ((inst >> 27) & 0b11111) {
+                case 0: op = rv_op_th_srb; break;
+                case 1: op = rv_op_th_sbib; break;
+                case 2: op = rv_op_th_surb; break;
+                case 3: op = rv_op_th_sbia; break;
+                case 4: op = rv_op_th_srh; break;
+                case 5: op = rv_op_th_shib; break;
+                case 6: op = rv_op_th_surh; break;
+                case 7: op = rv_op_th_shia; break;
+                case 8: op = rv_op_th_srw; break;
+                case 9: op = rv_op_th_swib; break;
+                case 10: op = rv_op_th_surw; break;
+                case 11: op = rv_op_th_swia; break;
+                case 12: op = rv_op_th_srd; break;
+                case 13: op = rv_op_th_sdib; break;
+                case 14: op = rv_op_th_surd; break;
+                case 15: op = rv_op_th_sdia; break;
+                }
+                break;
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadmempair(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 4:
+                switch ((inst >> 27) & 0b11111) {
+                case 28: op = rv_op_th_lwd; break;
+                case 30: op = rv_op_th_lwud; break;
+                case 31: op = rv_op_th_ldd; break;
+                }
+                break;
+            case 5:
+                switch ((inst >> 27) & 0b11111) {
+                case 28: op = rv_op_th_swd; break;
+                case 31: op = rv_op_th_sdd; break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
+
+void decode_xtheadsync(rv_decode *dec, rv_isa isa)
+{
+    rv_inst inst = dec->inst;
+    rv_opcode op = rv_op_illegal;
+
+    switch (((inst >> 0) & 0b11)) {
+    case 3:
+        switch (((inst >> 2) & 0b11111)) {
+        case 2:
+            /* custom-0 */
+            switch ((inst >> 12) & 0b111) {
+            case 0:
+                switch ((inst >> 25) & 0b1111111) {
+                case 0b0000010: op = rv_op_th_sfence_vmas; break;
+                case 0b0000000:
+                    switch ((inst >> 20) & 0b11111) {
+                    case 0b11000: op = rv_op_th_sync; break;
+                    case 0b11010: op = rv_op_th_sync_i; break;
+                    case 0b11011: op = rv_op_th_sync_is; break;
+                    case 0b11001: op = rv_op_th_sync_s; break;
+                    }
+                    break;
+                }
+                break;
+            }
+            break;
+            /* custom-0 */
+        }
+        break;
+    }
+
+    dec->op = op;
+}
diff --git a/disas/riscv-xthead.h b/disas/riscv-xthead.h
new file mode 100644
index 0000000000..fcd42746e7
--- /dev/null
+++ b/disas/riscv-xthead.h
@@ -0,0 +1,28 @@
+/*
+ * QEMU disassembler -- RISC-V specific header (xthead*).
+ *
+ * Copyright (c) 2023 VRULL GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef DISAS_RISCV_XTHEAD_H
+#define DISAS_RISCV_XTHEAD_H
+
+#include "disas/riscv.h"
+
+extern const rv_opcode_data xthead_opcode_data[];
+
+void decode_xtheadba(rv_decode *, rv_isa);
+void decode_xtheadbb(rv_decode *, rv_isa);
+void decode_xtheadbs(rv_decode *, rv_isa);
+void decode_xtheadcmo(rv_decode *, rv_isa);
+void decode_xtheadcondmov(rv_decode *, rv_isa);
+void decode_xtheadfmemidx(rv_decode *, rv_isa);
+void decode_xtheadfmv(rv_decode *, rv_isa);
+void decode_xtheadmac(rv_decode *, rv_isa);
+void decode_xtheadmemidx(rv_decode *, rv_isa);
+void decode_xtheadmempair(rv_decode *, rv_isa);
+void decode_xtheadsync(rv_decode *, rv_isa);
+
+#endif /* DISAS_RISCV_XTHEAD_H */
diff --git a/disas/riscv.c b/disas/riscv.c
index c7bfd4ed32..94e568a7e9 100644
--- a/disas/riscv.c
+++ b/disas/riscv.c
@@ -18,11 +18,13 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/bitops.h"
 #include "disas/dis-asm.h"
 #include "target/riscv/cpu_cfg.h"
 #include "disas/riscv.h"
 
 /* Vendor extensions */
+#include "disas/riscv-xthead.h"
 #include "disas/riscv-xventana.h"
 
 typedef enum {
@@ -3869,6 +3871,26 @@ static uint32_t operand_zcmp_rlist(rv_inst inst)
     return ((inst << 56) >> 60);
 }
 
+static uint32_t operand_imm6(rv_inst inst)
+{
+    return (inst << 38) >> 60;
+}
+
+static uint32_t operand_imm2(rv_inst inst)
+{
+    return (inst << 37) >> 62;
+}
+
+static uint32_t operand_immh(rv_inst inst)
+{
+    return (inst << 32) >> 58;
+}
+
+static uint32_t operand_imml(rv_inst inst)
+{
+    return (inst << 38) >> 58;
+}
+
 static uint32_t calculate_stack_adj(rv_isa isa, uint32_t rlist, uint32_t spimm)
 {
     int xlen_bytes_log2 = isa == rv64 ? 3 : 2;
@@ -4233,6 +4255,38 @@ static void decode_inst_operands(rv_decode *dec, rv_isa isa)
     case rv_codec_zcmt_jt:
         dec->imm = operand_tbl_index(inst);
         break;
+    case rv_codec_r2_imm5:
+        dec->rd = operand_rd(inst);
+        dec->rs1 = operand_rs1(inst);
+        dec->imm = operand_rs2(inst);
+        break;
+    case rv_codec_r2:
+        dec->rd = operand_rd(inst);
+        dec->rs1 = operand_rs1(inst);
+        break;
+    case rv_codec_r2_imm6:
+        dec->rd = operand_rd(inst);
+        dec->rs1 = operand_rs1(inst);
+        dec->imm = operand_imm6(inst);
+        break;
+    case rv_codec_r_imm2:
+        dec->rd = operand_rd(inst);
+        dec->rs1 = operand_rs1(inst);
+        dec->rs2 = operand_rs2(inst);
+        dec->imm = operand_imm2(inst);
+        break;
+    case rv_codec_r2_immhl:
+        dec->rd = operand_rd(inst);
+        dec->rs1 = operand_rs1(inst);
+        dec->imm = operand_immh(inst);
+        dec->imm1 = operand_imml(inst);
+        break;
+    case rv_codec_r2_imm2_imm5:
+        dec->rd = operand_rd(inst);
+        dec->rs1 = operand_rs1(inst);
+        dec->imm = sextract32(operand_rs2(inst), 0, 5);
+        dec->imm1 = operand_imm2(inst);
+        break;
     };
 }
 
@@ -4446,6 +4500,10 @@ static void format_inst(char *buf, size_t buflen, size_t tab, rv_decode *dec)
             snprintf(tmp, sizeof(tmp), "%u", ((uint32_t)dec->imm & 0b11111));
             append(buf, tmp, buflen);
             break;
+        case 'j':
+            snprintf(tmp, sizeof(tmp), "%d", dec->imm1);
+            append(buf, tmp, buflen);
+            break;
         case 'o':
             snprintf(tmp, sizeof(tmp), "%d", dec->imm);
             append(buf, tmp, buflen);
@@ -4711,6 +4769,17 @@ disasm_inst(char *buf, size_t buflen, rv_isa isa, uint64_t pc, rv_inst inst,
         void (*decode_func)(rv_decode *, rv_isa);
     } decoders[] = {
         { always_true_p, rvi_opcode_data, decode_inst_opcode },
+        { has_xtheadba_p, xthead_opcode_data, decode_xtheadba },
+        { has_xtheadbb_p, xthead_opcode_data, decode_xtheadbb },
+        { has_xtheadbs_p, xthead_opcode_data, decode_xtheadbs },
+        { has_xtheadcmo_p, xthead_opcode_data, decode_xtheadcmo },
+        { has_xtheadcondmov_p, xthead_opcode_data, decode_xtheadcondmov },
+        { has_xtheadfmemidx_p, xthead_opcode_data, decode_xtheadfmemidx },
+        { has_xtheadfmv_p, xthead_opcode_data, decode_xtheadfmv },
+        { has_xtheadmac_p, xthead_opcode_data, decode_xtheadmac },
+        { has_xtheadmemidx_p, xthead_opcode_data, decode_xtheadmemidx },
+        { has_xtheadmempair_p, xthead_opcode_data, decode_xtheadmempair },
+        { has_xtheadsync_p, xthead_opcode_data, decode_xtheadsync },
         { has_XVentanaCondOps_p, ventana_opcode_data, decode_xventanacondops },
     };
 
diff --git a/disas/riscv.h b/disas/riscv.h
index 460196510c..052a0c4281 100644
--- a/disas/riscv.h
+++ b/disas/riscv.h
@@ -159,6 +159,12 @@ typedef enum {
     rv_codec_zcmp_cm_pushpop,
     rv_codec_zcmp_cm_mv,
     rv_codec_zcmt_jt,
+    rv_codec_r2_imm5,
+    rv_codec_r2,
+    rv_codec_r2_imm6,
+    rv_codec_r_imm2,
+    rv_codec_r2_immhl,
+    rv_codec_r2_imm2_imm5,
 } rv_codec;
 
 /* structures */
@@ -185,6 +191,7 @@ typedef struct {
     uint64_t  inst;
     const rv_opcode_data *opcode_data;
     int32_t   imm;
+    int32_t   imm1;
     uint16_t  op;
     uint8_t   codec;
     uint8_t   rd;
@@ -283,5 +290,10 @@ enum {
 #define rv_fmt_push_rlist             "O\tx,-i"
 #define rv_fmt_pop_rlist              "O\tx,i"
 #define rv_fmt_zcmt_index             "O\ti"
+#define rv_fmt_rd_rs1_rs2_imm         "O\t0,1,2,i"
+#define rv_fmt_frd_rs1_rs2_imm        "O\t3,1,2,i"
+#define rv_fmt_rd_rs1_immh_imml       "O\t0,1,i,j"
+#define rv_fmt_rd_rs1_immh_imml_addr  "O\t0,(1),i,j"
+#define rv_fmt_rd2_imm                "O\t0,2,(1),i"
 
 #endif /* DISAS_RISCV_H */
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index 0b4fe4b540..6b7e736bc2 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -157,6 +157,17 @@ static inline bool has_xthead_p(const RISCVCPUConfig *cfg)
         return cfg->ext_ ## ext ; \
     }
 
+MATERIALISE_EXT_PREDICATE(xtheadba)
+MATERIALISE_EXT_PREDICATE(xtheadbb)
+MATERIALISE_EXT_PREDICATE(xtheadbs)
+MATERIALISE_EXT_PREDICATE(xtheadcmo)
+MATERIALISE_EXT_PREDICATE(xtheadcondmov)
+MATERIALISE_EXT_PREDICATE(xtheadfmemidx)
+MATERIALISE_EXT_PREDICATE(xtheadfmv)
+MATERIALISE_EXT_PREDICATE(xtheadmac)
+MATERIALISE_EXT_PREDICATE(xtheadmemidx)
+MATERIALISE_EXT_PREDICATE(xtheadmempair)
+MATERIALISE_EXT_PREDICATE(xtheadsync)
 MATERIALISE_EXT_PREDICATE(XVentanaCondOps)
 
 #endif
