s390x/tcg: factor out and fix DATA exception injection

The DXC is to be stored in the low core, and only in the FPC in case AFP
is enabled in CR0. Stub is not required in current code, but this way
we never run into problems.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180927130303.12236-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 6f8861e5540c02af2f384804a5f03650012c02a2..5e50c3a303da83f40062a389f003685956684d02 100644 (file)
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -322,6 +322,7 @@ extern const struct VMStateDescription vmstate_s390_cpu;
 #define CR0_LOWPROT             0x0000000010000000ULL
 #define CR0_SECONDARY           0x0000000004000000ULL
 #define CR0_EDAT                0x0000000000800000ULL
+#define CR0_AFP                 0x0000000000040000ULL
 #define CR0_EMERGENCY_SIGNAL_SC 0x0000000000004000ULL
 #define CR0_EXTERNAL_CALL_SC    0x0000000000002000ULL
 #define CR0_CKC_SC              0x0000000000000800ULL

diff --git a/target/s390x/excp_helper.c b/target/s390x/excp_helper.c
index 5dab3387c30a2e8fb8e89698cfe955e37431bfba..cd76c3163a75f2fa8c73ee6087b7a37963958de7 100644 (file)
--- a/target/s390x/excp_helper.c
+++ b/target/s390x/excp_helper.c
@@ -21,6 +21,7 @@
 #include "qemu/osdep.h"
 #include "cpu.h"
 #include "internal.h"
+#include "exec/helper-proto.h"
 #include "qemu/timer.h"
 #include "exec/exec-all.h"
 #include "exec/cpu_ldst.h"
@@ -61,6 +62,28 @@ void QEMU_NORETURN tcg_s390_program_interrupt(CPUS390XState *env, uint32_t code,
     cpu_loop_exit(cs);
 }
 
+void QEMU_NORETURN tcg_s390_data_exception(CPUS390XState *env, uint32_t dxc,
+                                           uintptr_t ra)
+{
+    g_assert(dxc <= 0xff);
+#if !defined(CONFIG_USER_ONLY)
+    /* Store the DXC into the lowcore */
+    stl_phys(CPU(s390_env_get_cpu(env))->as,
+             env->psa + offsetof(LowCore, data_exc_code), dxc);
+#endif
+
+    /* Store the DXC into the FPC if AFP is enabled */
+    if (env->cregs[0] & CR0_AFP) {
+        env->fpc = deposit32(env->fpc, 8, 8, dxc);
+    }
+    tcg_s390_program_interrupt(env, PGM_DATA, ILEN_AUTO, ra);
+}
+
+void HELPER(data_exception)(CPUS390XState *env, uint32_t dxc)
+{
+    tcg_s390_data_exception(env, dxc, GETPC());
+}
+
 #if defined(CONFIG_USER_ONLY)
 
 void s390_cpu_do_interrupt(CPUState *cs)

diff --git a/target/s390x/fpu_helper.c b/target/s390x/fpu_helper.c
index 5c5b451b3b301e84aac3fe24b8b4abc84c3b7654..1b662d2520223eca9d1583dcaf0fd7019c07d049 100644 (file)
--- a/target/s390x/fpu_helper.c
+++ b/target/s390x/fpu_helper.c
@@ -21,6 +21,7 @@
 #include "qemu/osdep.h"
 #include "cpu.h"
 #include "internal.h"
+#include "tcg_s390x.h"
 #include "exec/exec-all.h"
 #include "exec/cpu_ldst.h"
 #include "exec/helper-proto.h"
@@ -40,14 +41,6 @@
      ? (mask / (from / to)) & to    \
      : (mask & from) * (to / from))
 
-static void ieee_exception(CPUS390XState *env, uint32_t dxc, uintptr_t retaddr)
-{
-    /* Install the DXC code.  */
-    env->fpc = (env->fpc & ~0xff00) | (dxc << 8);
-    /* Trap.  */
-    s390_program_interrupt(env, PGM_DATA, ILEN_AUTO, retaddr);
-}
-
 /* Should be called after any operation that may raise IEEE exceptions.  */
 static void handle_exceptions(CPUS390XState *env, uintptr_t retaddr)
 {
@@ -75,7 +68,7 @@ static void handle_exceptions(CPUS390XState *env, uintptr_t retaddr)
     /* Send signals for enabled exceptions.  */
     s390_exc &= env->fpc >> 24;
     if (s390_exc) {
-        ieee_exception(env, s390_exc, retaddr);
+        tcg_s390_data_exception(env, s390_exc, retaddr);
     }
 }
 
@@ -773,6 +766,6 @@ void HELPER(sfas)(CPUS390XState *env, uint64_t val)
        is also 1, a simulated-iee-exception trap occurs.  */
     s390_exc = (signalling >> 16) & (source >> 24);
     if (s390_exc) {
-        ieee_exception(env, s390_exc | 3, GETPC());
+        tcg_s390_data_exception(env, s390_exc | 3, GETPC());
     }
 }

diff --git a/target/s390x/helper.h b/target/s390x/helper.h
index 97c60ca7bc87b17688875843dfa9eb4732eb7655..018e9dd414874ac63d5868e280090fec660afe4d 100644 (file)
--- a/target/s390x/helper.h
+++ b/target/s390x/helper.h
@@ -1,4 +1,5 @@
 DEF_HELPER_2(exception, noreturn, env, i32)
+DEF_HELPER_2(data_exception, noreturn, env, i32)
 DEF_HELPER_FLAGS_4(nc, TCG_CALL_NO_WG, i32, env, i32, i64, i64)
 DEF_HELPER_FLAGS_4(oc, TCG_CALL_NO_WG, i32, env, i32, i64, i64)
 DEF_HELPER_FLAGS_4(xc, TCG_CALL_NO_WG, i32, env, i32, i64, i64)

diff --git a/target/s390x/tcg-stub.c b/target/s390x/tcg-stub.c
index dc444fc8675655c202bbefd34f8e73569a70332f..32adb7276a113215b6503a75bacc56ff510c44bb 100644 (file)
--- a/target/s390x/tcg-stub.c
+++ b/target/s390x/tcg-stub.c
@@ -23,3 +23,8 @@ void QEMU_NORETURN tcg_s390_program_interrupt(CPUS390XState *env, uint32_t code,
 {
     g_assert_not_reached();
 }
+void QEMU_NORETURN tcg_s390_data_exception(CPUS390XState *env, uint32_t dxc,
+                                           uintptr_t ra)
+{
+    g_assert_not_reached();
+}

diff --git a/target/s390x/tcg_s390x.h b/target/s390x/tcg_s390x.h
index d1fe01ef7e74ea720b1676e6fdecfe5c2b5a74d7..ab2c4ba703275f2f5291d320b33f8b963870e920 100644 (file)
--- a/target/s390x/tcg_s390x.h
+++ b/target/s390x/tcg_s390x.h
@@ -16,5 +16,7 @@
 void tcg_s390_tod_updated(CPUState *cs, run_on_cpu_data opaque);
 void QEMU_NORETURN tcg_s390_program_interrupt(CPUS390XState *env, uint32_t code,
                                               int ilen, uintptr_t ra);
+void QEMU_NORETURN tcg_s390_data_exception(CPUS390XState *env, uint32_t dxc,
+                                           uintptr_t ra);
 
 #endif /* TCG_S390X_H */

diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index 59b1e5893c8477448b575846de47f4fdfc657d40..43b736335f008f38aced693442dda174b37b8bf6 100644 (file)
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -314,18 +314,17 @@ static inline void gen_illegal_opcode(DisasContext *s)
     gen_program_exception(s, PGM_OPERATION);
 }
 
-static inline void gen_trap(DisasContext *s)
+static inline void gen_data_exception(uint8_t dxc)
 {
-    TCGv_i32 t;
-
-    /* Set DXC to 0xff.  */
-    t = tcg_temp_new_i32();
-    tcg_gen_ld_i32(t, cpu_env, offsetof(CPUS390XState, fpc));
-    tcg_gen_ori_i32(t, t, 0xff00);
-    tcg_gen_st_i32(t, cpu_env, offsetof(CPUS390XState, fpc));
-    tcg_temp_free_i32(t);
+    TCGv_i32 tmp = tcg_const_i32(dxc);
+    gen_helper_data_exception(cpu_env, tmp);
+    tcg_temp_free_i32(tmp);
+}
 
-    gen_program_exception(s, PGM_DATA);
+static inline void gen_trap(DisasContext *s)
+{
+    /* Set DXC to 0xff */
+    gen_data_exception(0xff);
 }
 
 #ifndef CONFIG_USER_ONLY