target/loongarch: Add timer related instructions support.

This includes:
-RDTIME{L/H}.W
-RDTIME.D

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220606124333.2060567-30-yangxiaojuan@loongson.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

target/loongarch/disas.c

@@ -352,6 +352,9 @@ INSN(bitrev_w,     rr)
 INSN(bitrev_d,     rr)
 INSN(ext_w_h,      rr)
 INSN(ext_w_b,      rr)
+INSN(rdtimel_w,    rr)
+INSN(rdtimeh_w,    rr)
+INSN(rdtime_d,     rr)
 INSN(cpucfg,       rr)
 INSN(asrtle_d,     rr_jk)
 INSN(asrtgt_d,     rr_jk)

target/loongarch/helper.h

@@ -93,6 +93,8 @@ DEF_HELPER_2(frint_d, i64, env, i64)
 
 DEF_HELPER_FLAGS_2(set_rounding_mode, TCG_CALL_NO_RWG, void, env, i32)
 
+DEF_HELPER_1(rdtime_d, i64, env)
+
 /* CSRs helper */
 DEF_HELPER_1(csrrd_pgd, i64, env)
 DEF_HELPER_1(csrrd_tval, i64, env)

target/loongarch/insn_trans/trans_extra.c.inc

@@ -33,6 +33,39 @@ static bool trans_asrtgt_d(DisasContext *ctx, arg_asrtgt_d * a)
     return true;
 }
 
+static bool gen_rdtime(DisasContext *ctx, arg_rr *a,
+                       bool word, bool high)
+{
+    TCGv dst1 = gpr_dst(ctx, a->rd, EXT_NONE);
+    TCGv dst2 = gpr_dst(ctx, a->rj, EXT_NONE);
+
+    if (tb_cflags(ctx->base.tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
+    gen_helper_rdtime_d(dst1, cpu_env);
+    if (word) {
+        tcg_gen_sextract_tl(dst1, dst1, high ? 32 : 0, 32);
+    }
+    tcg_gen_ld_i64(dst2, cpu_env, offsetof(CPULoongArchState, CSR_TID));
+
+    return true;
+}
+
+static bool trans_rdtimel_w(DisasContext *ctx, arg_rdtimel_w *a)
+{
+    return gen_rdtime(ctx, a, 1, 0);
+}
+
+static bool trans_rdtimeh_w(DisasContext *ctx, arg_rdtimeh_w *a)
+{
+    return gen_rdtime(ctx, a, 1, 1);
+}
+
+static bool trans_rdtime_d(DisasContext *ctx, arg_rdtime_d *a)
+{
+    return gen_rdtime(ctx, a, 0, 0);
+}
+
 static bool trans_cpucfg(DisasContext *ctx, arg_cpucfg *a)
 {
     TCGv dest = gpr_dst(ctx, a->rd, EXT_NONE);

target/loongarch/insns.decode

@@ -309,6 +309,9 @@ break           0000 00000010 10100 ...............      @i15
 syscall         0000 00000010 10110 ...............      @i15
 asrtle_d        0000 00000000 00010 ..... ..... 00000    @rr_jk
 asrtgt_d        0000 00000000 00011 ..... ..... 00000    @rr_jk
+rdtimel_w       0000 00000000 00000 11000 ..... .....    @rr
+rdtimeh_w       0000 00000000 00000 11001 ..... .....    @rr
+rdtime_d        0000 00000000 00000 11010 ..... .....    @rr
 cpucfg          0000 00000000 00000 11011 ..... .....    @rr
 
 #

target/loongarch/op_helper.c

@@ -84,6 +84,19 @@ target_ulong helper_cpucfg(CPULoongArchState *env, target_ulong rj)
     return rj > 21 ? 0 : env->cpucfg[rj];
 }
 
+uint64_t helper_rdtime_d(CPULoongArchState *env)
+{
+    uint64_t plv;
+    LoongArchCPU *cpu = env_archcpu(env);
+
+    plv = FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PLV);
+    if (extract64(env->CSR_MISC, R_CSR_MISC_DRDTL_SHIFT + plv, 1)) {
+        do_raise_exception(env, EXCCODE_IPE, GETPC());
+    }
+
+    return cpu_loongarch_get_constant_timer_counter(cpu);
+}
+
 void helper_ertn(CPULoongArchState *env)
 {
     uint64_t csr_pplv, csr_pie;

target/loongarch/translate.c

@@ -25,6 +25,8 @@ static TCGv cpu_lladdr, cpu_llval;
 TCGv_i32 cpu_fcsr0;
 TCGv_i64 cpu_fpr[32];
 
+#include "exec/gen-icount.h"
+
 #define DISAS_STOP        DISAS_TARGET_0
 #define DISAS_EXIT        DISAS_TARGET_1
 #define DISAS_EXIT_UPDATE DISAS_TARGET_2