[Qemu-devel] [PATCH 08/10] target-s390x: wire up DIAG IPL in TCG mode

[Aurelien Jarno]

DIAG IPL is already implemented for KVM, but not wired from TCG. For
that change the format of the instruction so that we can get R1 and R3
numbers in addition to the function code.

The diag function can change plenty of things, including CC, so we
should enter with a static CC. Also it doesn't set the value of general
register 2 to 0 as in the current code. We also need to exit the CPU
loop after a reset, which means a new PSW.

Cc: Alexander Graf <address@hidden>
Cc: Richard Henderson <address@hidden>
Signed-off-by: Aurelien Jarno <address@hidden>
---
 target-s390x/helper.h      |  2 +-
 target-s390x/insn-data.def |  2 +-
 target-s390x/misc_helper.c | 13 ++++++++-----
 target-s390x/translate.c   | 16 ++++++++++------
 4 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/target-s390x/helper.h b/target-s390x/helper.h
index 7e048ec..6be9f44 100644
--- a/target-s390x/helper.h
+++ b/target-s390x/helper.h
@@ -87,7 +87,7 @@ DEF_HELPER_FLAGS_1(popcnt, TCG_CALL_NO_RWG_SE, i64, i64)
 
 #ifndef CONFIG_USER_ONLY
 DEF_HELPER_3(servc, i32, env, i64, i64)
-DEF_HELPER_4(diag, i64, env, i32, i64, i64)
+DEF_HELPER_4(diag, void, env, i32, i32, i32)
 DEF_HELPER_3(load_psw, noreturn, env, i64, i64)
 DEF_HELPER_FLAGS_2(spx, TCG_CALL_NO_RWG, void, env, i64)
 DEF_HELPER_FLAGS_1(stck, TCG_CALL_NO_RWG_SE, i64, env)
diff --git a/target-s390x/insn-data.def b/target-s390x/insn-data.def
index 1223670..fe5e591 100644
--- a/target-s390x/insn-data.def
+++ b/target-s390x/insn-data.def
@@ -835,7 +835,7 @@
 /* COMPARE AND SWAP AND PURGE */
     C(0xb250, CSP,     RRE,   Z,   0, ra2, 0, 0, csp, 0)
 /* DIAGNOSE (KVM hypercall) */
-    C(0x8300, DIAG,    RX_a,  Z,   0, 0, 0, 0, diag, 0)
+    C(0x8300, DIAG,    RSI,   Z,   0, 0, 0, 0, diag, 0)
 /* INSERT STORAGE KEY EXTENDED */
     C(0xb229, ISKE,    RRE,   Z,   0, r2_o, new, r1_8, iske, 0)
 /* INVALIDATE PAGE TABLE ENTRY */
diff --git a/target-s390x/misc_helper.c b/target-s390x/misc_helper.c
index b375ab7..e36d957 100644
--- a/target-s390x/misc_helper.c
+++ b/target-s390x/misc_helper.c
@@ -176,9 +176,15 @@ void handle_diag_308(CPUS390XState *env, uint64_t r1, 
uint64_t r3)
     switch (subcode) {
     case 0:
         modified_clear_reset(s390_env_get_cpu(env));
+        if (tcg_enabled()) {
+            cpu_loop_exit(CPU(s390_env_get_cpu(env)));
+        }
         break;
     case 1:
         load_normal_reset(s390_env_get_cpu(env));
+        if (tcg_enabled()) {
+            cpu_loop_exit(CPU(s390_env_get_cpu(env)));
+        }
         break;
     case 5:
         if ((r1 & 1) || (addr & 0x0fffULL)) {
@@ -225,9 +231,7 @@ void handle_diag_308(CPUS390XState *env, uint64_t r1, 
uint64_t r3)
 }
 #endif
 
-/* DIAG */
-uint64_t HELPER(diag)(CPUS390XState *env, uint32_t num, uint64_t mem,
-                      uint64_t code)
+void HELPER(diag)(CPUS390XState *env, uint32_t r1, uint32_t r3, uint32_t num)
 {
     uint64_t r;
 
@@ -242,6 +246,7 @@ uint64_t HELPER(diag)(CPUS390XState *env, uint32_t num, 
uint64_t mem,
         break;
     case 0x308:
         /* ipl */
+        handle_diag_308(env, r1, r3);
         r = 0;
         break;
     default:
@@ -252,8 +257,6 @@ uint64_t HELPER(diag)(CPUS390XState *env, uint32_t num, 
uint64_t mem,
     if (r) {
         program_interrupt(env, PGM_OPERATION, ILEN_LATER_INC);
     }
-
-    return r;
 }
 
 /* Set Prefix */
diff --git a/target-s390x/translate.c b/target-s390x/translate.c
index 9b87714..bde5e8a 100644
--- a/target-s390x/translate.c
+++ b/target-s390x/translate.c
@@ -2025,15 +2025,19 @@ static ExitStatus op_ct(DisasContext *s, DisasOps *o)
 #ifndef CONFIG_USER_ONLY
 static ExitStatus op_diag(DisasContext *s, DisasOps *o)
 {
-    TCGv_i32 tmp;
+    TCGv_i32 r1 = tcg_const_i32(get_field(s->fields, r1));
+    TCGv_i32 r3 = tcg_const_i32(get_field(s->fields, r3));
+    TCGv_i32 func_code = tcg_const_i32(get_field(s->fields, i2));
 
     check_privileged(s);
-    potential_page_fault(s);
+    update_psw_addr(s);
+    gen_op_calc_cc(s);
 
-    /* We pretend the format is RX_a so that D2 is the field we want.  */
-    tmp = tcg_const_i32(get_field(s->fields, d2) & 0xfff);
-    gen_helper_diag(regs[2], cpu_env, tmp, regs[2], regs[1]);
-    tcg_temp_free_i32(tmp);
+    gen_helper_diag(cpu_env, r1, r3, func_code);
+
+    tcg_temp_free_i32(func_code);
+    tcg_temp_free_i32(r3);
+    tcg_temp_free_i32(r1);
     return NO_EXIT;
 }
 #endif
-- 
2.1.4