[PATCH v4 2/7] target/mips: Add support for MIPS<32|64>R6 CRC32 ISA

[Aleksandar Markovic]

From: Aleksandar Markovic <address@hidden>

Add support for eight CRC-related MIPS<32|64>R6 instructions.

Signed-off-by: Aleksandar Markovic <address@hidden>
---
 disas/mips.c            |   8 +++
 target/mips/helper.h    |   2 +
 target/mips/op_helper.c |  19 ++++++++
 target/mips/translate.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 156 insertions(+)

diff --git a/disas/mips.c b/disas/mips.c
index dfefe5e..75c48b3 100644
--- a/disas/mips.c
+++ b/disas/mips.c
@@ -1409,6 +1409,14 @@ const struct mips_opcode mips_builtin_opcodes[] =
 {"dvp",        "t",     0x41600024, 0xffe0ffff, TRAP|WR_t,            0, 
I32R6},
 {"evp",        "",      0x41600004, 0xffffffff, TRAP,                 0, 
I32R6},
 {"evp",        "t",     0x41600004, 0xffe0ffff, TRAP|WR_t,            0, 
I32R6},
+{"crc32b",     "t,v,t", 0x7c00000f, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I32R6},
+{"crc32h",     "t,v,t", 0x7c00004f, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I32R6},
+{"crc32w",     "t,v,t", 0x7c00008f, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I32R6},
+{"crc32d",     "t,v,t", 0x7c0000cf, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I64R6},
+{"crc32cb",    "t,v,t", 0x7c00010f, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I32R6},
+{"crc32ch",    "t,v,t", 0x7c00014f, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I32R6},
+{"crc32cw",    "t,v,t", 0x7c00018f, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I32R6},
+{"crc32cd",    "t,v,t", 0x7c0001cf, 0xfc00ff3f, WR_d | RD_s | RD_t,   0, 
I64R6},
 
 /* MSA */
 {"sll.b",   "+d,+e,+f", 0x7800000d, 0xffe0003f, WR_VD|RD_VS|RD_VT,  0, MSA},
diff --git a/target/mips/helper.h b/target/mips/helper.h
index 7b8ad74..2095330 100644
--- a/target/mips/helper.h
+++ b/target/mips/helper.h
@@ -40,6 +40,8 @@ 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)
 
 #ifndef CONFIG_USER_ONLY
diff --git a/target/mips/op_helper.c b/target/mips/op_helper.c
index 18fcee4..5cd396d 100644
--- a/target/mips/op_helper.c
+++ b/target/mips/op_helper.c
@@ -27,6 +27,8 @@
 #include "exec/memop.h"
 #include "sysemu/kvm.h"
 #include "fpu/softfloat.h"
+#include "qemu/crc32c.h"
+#include <zlib.h>
 
 /*****************************************************************************/
 /* Exceptions processing helpers */
@@ -350,6 +352,23 @@ 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/arm/helper-a64.c */
+target_ulong helper_crc32(target_ulong val, target_ulong m, uint32_t sz)
+{
+    uint8_t buf[8];
+
+    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];
+
+    stq_le_p(buf, m);
+    return (int32_t) (crc32c(val, buf, sz) ^ 0xffffffff);
+}
+
 #ifndef CONFIG_USER_ONLY
 
 static inline hwaddr do_translate_address(CPUMIPSState *env,
diff --git a/target/mips/translate.c b/target/mips/translate.c
index 4bff585..1b38356 100644
--- a/target/mips/translate.c
+++ b/target/mips/translate.c
@@ -451,6 +451,7 @@ enum {
     OPC_LWE            = 0x2F | OPC_SPECIAL3,
 
     /* R6 */
+    OPC_CRC32          = 0x0F | OPC_SPECIAL3,
     R6_OPC_PREF        = 0x35 | OPC_SPECIAL3,
     R6_OPC_CACHE       = 0x25 | OPC_SPECIAL3,
     R6_OPC_LL          = 0x36 | OPC_SPECIAL3,
@@ -2547,6 +2548,7 @@ typedef struct DisasContext {
     bool nan2008;
     bool abs2008;
     bool saar;
+    bool crcp;
 } DisasContext;
 
 #define DISAS_STOP       DISAS_TARGET_0
@@ -27117,11 +27119,96 @@ static void decode_opc_special2_legacy(CPUMIPSState 
*env, DisasContext *ctx)
     }
 }
 
+static void gen_crc32(DisasContext *ctx, int rd, int rs, int rt, int sz,
+                      int crc32c)
+{
+    TCGv t0;
+    TCGv t1;
+    TCGv_i32 tsz = tcg_const_i32(1 << sz);
+    uint64_t mask = 0;
+
+    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 (sz != 3) {
+        switch (sz) {
+        case 0:
+            mask = 0xFF;
+            break;
+        case 1:
+            mask = 0xFFFF;
+            break;
+        case 2:
+            mask = 0xFFFFFFFF;
+            break;
+        }
+        tcg_gen_andi_tl(t1, t1, mask);
+    }
+
+    if (crc32c) {
+        gen_helper_crc32c(cpu_gpr[rd], t0, t1, tsz);
+    } else {
+        gen_helper_crc32(cpu_gpr[rd], t0, t1, tsz);
+    }
+
+    tcg_temp_free(t0);
+    tcg_temp_free(t1);
+    tcg_temp_free_i32(tsz);
+}
+
+static void gen_crc32b(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 0, 0);
+}
+
+static void gen_crc32h(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 1, 0);
+}
+
+static void gen_crc32w(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 2, 0);
+}
+
+static void gen_crc32d(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 3, 0);
+}
+
+static void gen_crc32cb(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 0, 1);
+}
+
+static void gen_crc32ch(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 1, 1);
+}
+
+static void gen_crc32cw(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 2, 1);
+}
+
+static void gen_crc32cd(DisasContext *ctx, int rd, int rs, int rt)
+{
+    gen_crc32(ctx, rd, rs, rt, 3, 1);
+}
+
 static void decode_opc_special3_r6(CPUMIPSState *env, DisasContext *ctx)
 {
     int rs, rt, rd, sa;
     uint32_t op1, op2;
     int16_t imm;
+    int sz, crc32c;
 
     rs = (ctx->opcode >> 21) & 0x1f;
     rt = (ctx->opcode >> 16) & 0x1f;
@@ -27131,6 +27218,45 @@ static void decode_opc_special3_r6(CPUMIPSState *env, 
DisasContext *ctx)
 
     op1 = MASK_SPECIAL3(ctx->opcode);
     switch (op1) {
+    case OPC_CRC32:
+        sz = extract32(ctx->opcode, 6, 2);
+        crc32c = extract32(ctx->opcode, 8, 3);
+        if (unlikely(!ctx->crcp) ||
+            unlikely((sz == 3) && (!(ctx->hflags & MIPS_HFLAG_64))) ||
+            unlikely((crc32c >= 2))) {
+            generate_exception_end(ctx, EXCP_RI);
+        }
+        switch (sz) {
+        case 0:
+            if (crc32c) {
+                gen_crc32cb(ctx, rt, rs, rt);
+            } else {
+                gen_crc32b(ctx, rt, rs, rt);
+            }
+            break;
+        case 1:
+            if (crc32c) {
+                gen_crc32ch(ctx, rt, rs, rt);
+            } else {
+                gen_crc32h(ctx, rt, rs, rt);
+            }
+            break;
+        case 2:
+            if (crc32c) {
+                gen_crc32cw(ctx, rt, rs, rt);
+            } else {
+                gen_crc32w(ctx, rt, rs, rt);
+            }
+            break;
+        case 3:
+            if (crc32c) {
+                gen_crc32cd(ctx, rt, rs, rt);
+            } else {
+                gen_crc32d(ctx, rt, rs, rt);
+            }
+            break;
+        }
+        break;
     case R6_OPC_PREF:
         if (rt >= 24) {
             /* hint codes 24-31 are reserved and signal RI */
@@ -30727,6 +30853,7 @@ static void mips_tr_init_disas_context(DisasContextBase 
*dcbase, CPUState *cs)
     ctx->mrp = (env->CP0_Config5 >> CP0C5_MRP) & 1;
     ctx->nan2008 = (env->active_fpu.fcr31 >> FCR31_NAN2008) & 1;
     ctx->abs2008 = (env->active_fpu.fcr31 >> FCR31_ABS2008) & 1;
+    ctx->crcp = (env->CP0_Config5 >> CP0C5_CRCP) & 1;
     restore_cpu_state(env, ctx);
 #ifdef CONFIG_USER_ONLY
         ctx->mem_idx = MIPS_HFLAG_UM;
-- 
2.7.4