[PULL 01/17] target/mips: Add support for emulation of CRC32 instructions

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

From: Yongbok Kim <yongbok.kim@mips.com>

Add emulation of MIPS' CRC32 (Cyclic Redundancy Check) instructions.
Reuse zlib crc32() and Linux crc32c().

Corresponding disassembly has been added in commit 99029be1c28
("target/mips: Add implementation of GINVT instruction").

Signed-off-by: Yongbok Kim <yongbok.kim@mips.com>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Aleksandar Rakic <aleksandar.rakic@htecgroup.com>
Reviewed-by: Aleksandar Rikalo <arikalo@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <PA4PR09MB486489692D843DDFC25F3CF1846B2@PA4PR09MB4864.eurprd09.prod.outlook.com>
---
 target/mips/helper.h             |  2 ++
 target/mips/tcg/translate.h      |  2 ++
 target/mips/tcg/rel6.decode      |  5 +++++
 target/mips/tcg/op_helper.c      | 26 ++++++++++++++++++++++++++
 target/mips/tcg/rel6_translate.c | 12 ++++++++++++
 target/mips/tcg/translate.c      | 24 ++++++++++++++++++++++++
 target/mips/cpu-defs.c.inc       | 10 ++++++----
 target/mips/meson.build          |  1 +
 8 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/target/mips/helper.h b/target/mips/helper.h
index 7e400418281..b6cd53c8538 100644
--- a/target/mips/helper.h
+++ b/target/mips/helper.h
@@ -21,6 +21,8 @@ DEF_HELPER_FLAGS_1(bitswap, TCG_CALL_NO_RWG_SE, tl, tl)
 DEF_HELPER_FLAGS_1(dbitswap, TCG_CALL_NO_RWG_SE, tl, tl)
 #endif
 
+DEF_HELPER_3(crc32, tl, tl, tl, i32)
+DEF_HELPER_3(crc32c, tl, tl, tl, i32)
 DEF_HELPER_FLAGS_4(rotx, TCG_CALL_NO_RWG_SE, tl, tl, i32, i32, i32)
 
 /* microMIPS functions */
diff --git a/target/mips/tcg/translate.h b/target/mips/tcg/translate.h
index 1bf153d1838..428b53a0dac 100644
--- a/target/mips/tcg/translate.h
+++ b/target/mips/tcg/translate.h
@@ -51,6 +51,7 @@ typedef struct DisasContext {
     bool abs2008;
     bool mi;
     int gi;
+    bool crcp;
 } DisasContext;
 
 #define DISAS_STOP       DISAS_TARGET_0
@@ -181,6 +182,7 @@ bool gen_lsa(DisasContext *ctx, int rd, int rt, int rs, int sa);
 bool gen_dlsa(DisasContext *ctx, int rd, int rt, int rs, int sa);
 
 void gen_rdhwr(DisasContext *ctx, int rt, int rd, int sel);
+void gen_crc32(DisasContext *ctx, int rd, int rs, int rt, int sz, int crc32c);
 
 extern TCGv cpu_gpr[32], cpu_PC;
 #if defined(TARGET_MIPS64)
diff --git a/target/mips/tcg/rel6.decode b/target/mips/tcg/rel6.decode
index d6989cf56e8..7fbcb109b4e 100644
--- a/target/mips/tcg/rel6.decode
+++ b/target/mips/tcg/rel6.decode
@@ -16,11 +16,16 @@
 
 &r                  rs rt rd sa
 
+&special3_crc       rs rt c sz
+
 @lsa                ...... rs:5 rt:5 rd:5 ... sa:2 ......   &r
+@crc32              ...... rs:5 rt:5 ..... c:3 sz:2 ......  &special3_crc
 
 LSA                 000000 ..... ..... ..... 000 .. 000101  @lsa
 DLSA                000000 ..... ..... ..... 000 .. 010101  @lsa
 
+CRC32               011111 ..... ..... 00000 ... .. 001111  @crc32
+
 REMOVED             010011 ----- ----- ----- ----- ------   # COP1X (COP3)
 
 REMOVED             011100 ----- ----- ----- ----- ------   # SPECIAL2
diff --git a/target/mips/tcg/op_helper.c b/target/mips/tcg/op_helper.c
index b906d10204b..4502ae2b5be 100644
--- a/target/mips/tcg/op_helper.c
+++ b/target/mips/tcg/op_helper.c
@@ -24,6 +24,8 @@
 #include "exec/helper-proto.h"
 #include "exec/memop.h"
 #include "fpu_helper.h"
+#include "qemu/crc32c.h"
+#include <zlib.h>
 
 static inline target_ulong bitswap(target_ulong v)
 {
@@ -142,6 +144,30 @@ target_ulong helper_rotx(target_ulong rs, uint32_t shift, uint32_t shiftx,
     return (int64_t)(int32_t)(uint32_t)tmp5;
 }
 
+/* these crc32 functions are based on target/loongarch/tcg/op_helper.c */
+target_ulong helper_crc32(target_ulong val, target_ulong m, uint32_t sz)
+{
+    uint8_t buf[8];
+    target_ulong mask = ((sz * 8) == 64) ?
+                        (target_ulong) -1ULL :
+                        ((1ULL << (sz * 8)) - 1);
+
+    m &= mask;
+    stq_le_p(buf, m);
+    return (int32_t) (crc32(val ^ 0xffffffff, buf, sz) ^ 0xffffffff);
+}
+
+target_ulong helper_crc32c(target_ulong val, target_ulong m, uint32_t sz)
+{
+    uint8_t buf[8];
+    target_ulong mask = ((sz * 8) == 64) ?
+                        (target_ulong) -1ULL :
+                        ((1ULL << (sz * 8)) - 1);
+    m &= mask;
+    stq_le_p(buf, m);
+    return (int32_t) (crc32c(val, buf, sz) ^ 0xffffffff);
+}
+
 void helper_fork(target_ulong arg1, target_ulong arg2)
 {
     /*
diff --git a/target/mips/tcg/rel6_translate.c b/target/mips/tcg/rel6_translate.c
index 59f237ba3ba..89335063977 100644
--- a/target/mips/tcg/rel6_translate.c
+++ b/target/mips/tcg/rel6_translate.c
@@ -33,3 +33,15 @@ static bool trans_DLSA(DisasContext *ctx, arg_r *a)
     }
     return gen_dlsa(ctx, a->rd, a->rt, a->rs, a->sa);
 }
+
+static bool trans_CRC32(DisasContext *ctx, arg_special3_crc *a)
+{
+    if (unlikely(!ctx->crcp)
+        || unlikely((a->sz == 3) && (!(ctx->hflags & MIPS_HFLAG_64)))
+        || unlikely((a->c >= 2))) {
+        gen_reserved_instruction(ctx);
+        return true;
+    }
+    gen_crc32(ctx, a->rt, a->rs, a->rt, a->sz, a->c);
+    return true;
+}
diff --git a/target/mips/tcg/translate.c b/target/mips/tcg/translate.c
index 8658315f938..5c80b030329 100644
--- a/target/mips/tcg/translate.c
+++ b/target/mips/tcg/translate.c
@@ -13449,6 +13449,29 @@ static void decode_opc_special2_legacy(CPUMIPSState *env, DisasContext *ctx)
     }
 }
 
+void gen_crc32(DisasContext *ctx, int rd, int rs, int rt, int sz,
+               int crc32c)
+{
+    TCGv t0;
+    TCGv t1;
+    TCGv_i32 tsz = tcg_constant_i32(1 << sz);
+    if (rd == 0) {
+        /* Treat as NOP. */
+        return;
+    }
+    t0 = tcg_temp_new();
+    t1 = tcg_temp_new();
+
+    gen_load_gpr(t0, rt);
+    gen_load_gpr(t1, rs);
+
+    if (crc32c) {
+        gen_helper_crc32c(cpu_gpr[rd], t0, t1, tsz);
+    } else {
+        gen_helper_crc32(cpu_gpr[rd], t0, t1, tsz);
+    }
+}
+
 static void decode_opc_special3_r6(CPUMIPSState *env, DisasContext *ctx)
 {
     int rs, rt, rd, sa;
@@ -15095,6 +15118,7 @@ static void mips_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     ctx->abs2008 = (env->active_fpu.fcr31 >> FCR31_ABS2008) & 1;
     ctx->mi = (env->CP0_Config5 >> CP0C5_MI) & 1;
     ctx->gi = (env->CP0_Config5 >> CP0C5_GI) & 3;
+    ctx->crcp = (env->CP0_Config5 >> CP0C5_CRCP) & 1;
     restore_cpu_state(env, ctx);
 #ifdef CONFIG_USER_ONLY
         ctx->mem_idx = MIPS_HFLAG_UM;
diff --git a/target/mips/cpu-defs.c.inc b/target/mips/cpu-defs.c.inc
index 922fc39138d..d93b9d341ac 100644
--- a/target/mips/cpu-defs.c.inc
+++ b/target/mips/cpu-defs.c.inc
@@ -756,8 +756,9 @@ const mips_def_t mips_defs[] =
                        (1 << CP0C3_RXI) | (1 << CP0C3_LPA) | (1 << CP0C3_VInt),
         .CP0_Config4 = MIPS_CONFIG4 | (1U << CP0C4_M) | (3 << CP0C4_IE) |
                        (1 << CP0C4_AE) | (0xfc << CP0C4_KScrExist),
-        .CP0_Config5 = MIPS_CONFIG5 | (1 << CP0C5_XNP) | (1 << CP0C5_VP) |
-                       (1 << CP0C5_LLB) | (1 << CP0C5_MRP) | (3 << CP0C5_GI),
+        .CP0_Config5 = MIPS_CONFIG5 | (1 << CP0C5_CRCP) | (1 << CP0C5_XNP) |
+                       (1 << CP0C5_VP) | (1 << CP0C5_LLB) | (1 << CP0C5_MRP) |
+                       (3 << CP0C5_GI),
         .CP0_Config5_rw_bitmask = (1 << CP0C5_MSAEn) | (1 << CP0C5_SBRI) |
                                   (1 << CP0C5_FRE) | (1 << CP0C5_UFE),
         .CP0_LLAddr_rw_bitmask = 0,
@@ -796,8 +797,9 @@ const mips_def_t mips_defs[] =
                        (1 << CP0C3_RXI) | (1 << CP0C3_LPA) | (1 << CP0C3_VInt),
         .CP0_Config4 = MIPS_CONFIG4 | (1U << CP0C4_M) | (3 << CP0C4_IE) |
                        (1 << CP0C4_AE) | (0xfc << CP0C4_KScrExist),
-        .CP0_Config5 = MIPS_CONFIG5 | (1 << CP0C5_XNP) | (1 << CP0C5_VP) |
-                       (1 << CP0C5_LLB) | (1 << CP0C5_MRP) | (3 << CP0C5_GI),
+        .CP0_Config5 = MIPS_CONFIG5 | (1 << CP0C5_CRCP) | (1 << CP0C5_XNP) |
+                       (1 << CP0C5_VP) | (1 << CP0C5_LLB) | (1 << CP0C5_MRP) |
+                       (3 << CP0C5_GI),
         .CP0_Config5_rw_bitmask = (1 << CP0C5_MSAEn) | (1 << CP0C5_SBRI) |
                                   (1 << CP0C5_FRE) | (1 << CP0C5_UFE),
         .CP0_LLAddr_rw_bitmask = 0,
diff --git a/target/mips/meson.build b/target/mips/meson.build
index 247979a2cfc..abf0ce3e8b9 100644
--- a/target/mips/meson.build
+++ b/target/mips/meson.build
@@ -7,6 +7,7 @@ mips_ss.add(files(
   'gdbstub.c',
   'msa.c',
 ))
+mips_ss.add(zlib)
 
 if have_system
   subdir('system')
-- 
2.49.0