target-s390x: basic PER event handling

This patch add basic support to generate PER exceptions. It adds two
fields to the cpu structure to record for the PER address and PER
code & ATMID values. When an exception is triggered and a PER event is
pending, the two PER values are copied to the lowcore area.

At the end of an instruction, an helper is checking for a possible
pending PER event and triggers an exception in that case. For that to
work with branches, we need to disable TB chaining when PER is
activated. Fortunately it's already in the TB flags.

Finally in case of a SERVICE CALL exception, we need to trigger the PER
exception immediately after.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index d3137be4bebc3f60c3efb377dce420b19d890861..f830208d25a002c551d3c2b0801013064ddf8df4 100644 (file)
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -111,6 +111,9 @@ typedef struct CPUS390XState {
     uint32_t int_svc_code;
     uint32_t int_svc_ilen;
 
+    uint64_t per_address;
+    uint16_t per_perc_atmid;
+
     uint64_t cregs[16]; /* control registers */
 
     ExtQueue ext_queue[MAX_EXT_QUEUE];

diff --git a/target-s390x/helper.c b/target-s390x/helper.c
index 90d273c09865a56d94a2e94831d6941c2c006947..ec847a26450e4b8ed48562bc067e73c4c6b9a472 100644 (file)
--- a/target-s390x/helper.c
+++ b/target-s390x/helper.c
@@ -250,25 +250,6 @@ void do_restart_interrupt(CPUS390XState *env)
     load_psw(env, mask, addr);
 }
 
-static void do_svc_interrupt(CPUS390XState *env)
-{
-    uint64_t mask, addr;
-    LowCore *lowcore;
-
-    lowcore = cpu_map_lowcore(env);
-
-    lowcore->svc_code = cpu_to_be16(env->int_svc_code);
-    lowcore->svc_ilen = cpu_to_be16(env->int_svc_ilen);
-    lowcore->svc_old_psw.mask = cpu_to_be64(get_psw_mask(env));
-    lowcore->svc_old_psw.addr = cpu_to_be64(env->psw.addr + env->int_svc_ilen);
-    mask = be64_to_cpu(lowcore->svc_new_psw.mask);
-    addr = be64_to_cpu(lowcore->svc_new_psw.addr);
-
-    cpu_unmap_lowcore(lowcore);
-
-    load_psw(env, mask, addr);
-}
-
 static void do_program_interrupt(CPUS390XState *env)
 {
     uint64_t mask, addr;
@@ -292,6 +273,14 @@ static void do_program_interrupt(CPUS390XState *env)
 
     lowcore = cpu_map_lowcore(env);
 
+    /* Signal PER events with the exception.  */
+    if (env->per_perc_atmid) {
+        env->int_pgm_code |= PGM_PER;
+        lowcore->per_address = cpu_to_be64(env->per_address);
+        lowcore->per_perc_atmid = cpu_to_be16(env->per_perc_atmid);
+        env->per_perc_atmid = 0;
+    }
+
     lowcore->pgm_ilen = cpu_to_be16(ilen);
     lowcore->pgm_code = cpu_to_be16(env->int_pgm_code);
     lowcore->program_old_psw.mask = cpu_to_be64(get_psw_mask(env));
@@ -308,6 +297,33 @@ static void do_program_interrupt(CPUS390XState *env)
     load_psw(env, mask, addr);
 }
 
+static void do_svc_interrupt(CPUS390XState *env)
+{
+    uint64_t mask, addr;
+    LowCore *lowcore;
+
+    lowcore = cpu_map_lowcore(env);
+
+    lowcore->svc_code = cpu_to_be16(env->int_svc_code);
+    lowcore->svc_ilen = cpu_to_be16(env->int_svc_ilen);
+    lowcore->svc_old_psw.mask = cpu_to_be64(get_psw_mask(env));
+    lowcore->svc_old_psw.addr = cpu_to_be64(env->psw.addr + env->int_svc_ilen);
+    mask = be64_to_cpu(lowcore->svc_new_psw.mask);
+    addr = be64_to_cpu(lowcore->svc_new_psw.addr);
+
+    cpu_unmap_lowcore(lowcore);
+
+    load_psw(env, mask, addr);
+
+    /* When a PER event is pending, the PER exception has to happen
+       immediately after the SERVICE CALL one.  */
+    if (env->per_perc_atmid) {
+        env->int_pgm_code = PGM_PER;
+        env->int_pgm_ilen = env->int_svc_ilen;
+        do_program_interrupt(env);
+    }
+}
+
 #define VIRTIO_SUBCODE_64 0x0D00
 
 static void do_ext_interrupt(CPUS390XState *env)

diff --git a/target-s390x/helper.h b/target-s390x/helper.h
index 53db5193d90a37ef56a1570cf68bc803256008cb..7d2fa904ebc56d746199bce9c95001a37a7216ac 100644 (file)
--- a/target-s390x/helper.h
+++ b/target-s390x/helper.h
@@ -116,6 +116,7 @@ DEF_HELPER_FLAGS_2(lura, TCG_CALL_NO_WG, i64, env, i64)
 DEF_HELPER_FLAGS_2(lurag, TCG_CALL_NO_WG, i64, env, i64)
 DEF_HELPER_FLAGS_3(stura, TCG_CALL_NO_WG, void, env, i64, i64)
 DEF_HELPER_FLAGS_3(sturg, TCG_CALL_NO_WG, void, env, i64, i64)
+DEF_HELPER_1(per_check_exception, void, env)
 
 DEF_HELPER_2(xsch, void, env, i64)
 DEF_HELPER_2(csch, void, env, i64)

diff --git a/target-s390x/misc_helper.c b/target-s390x/misc_helper.c
index 7d66ce1f498bfeec3ea460e9c2cbc28a252e67cc..e636464363ea2cb7ff3136c3e5e8e7cdae52e2b2 100644 (file)
--- a/target-s390x/misc_helper.c
+++ b/target-s390x/misc_helper.c
@@ -594,3 +594,18 @@ void HELPER(chsc)(CPUS390XState *env, uint64_t inst)
     ioinst_handle_chsc(cpu, inst >> 16);
 }
 #endif
+
+#ifndef CONFIG_USER_ONLY
+void HELPER(per_check_exception)(CPUS390XState *env)
+{
+    CPUState *cs = CPU(s390_env_get_cpu(env));
+
+    if (env->per_perc_atmid) {
+        env->int_pgm_code = PGM_PER;
+        env->int_pgm_ilen = get_ilen(cpu_ldub_code(env, env->per_address));
+
+        cs->exception_index = EXCP_PGM;
+        cpu_loop_exit(cs);
+    }
+}
+#endif

diff --git a/target-s390x/translate.c b/target-s390x/translate.c
index df3389d4c77d2163b17c589af01ee3471bb83935..2013a816ddfc8479bd1573acebef0b00e9e435ab 100644 (file)
--- a/target-s390x/translate.c
+++ b/target-s390x/translate.c
@@ -568,7 +568,8 @@ static int use_goto_tb(DisasContext *s, uint64_t dest)
     return (((dest & TARGET_PAGE_MASK) == (s->tb->pc & TARGET_PAGE_MASK)
              || (dest & TARGET_PAGE_MASK) == ((s->pc - 1) & TARGET_PAGE_MASK))
             && !s->singlestep_enabled
-            && !(s->tb->cflags & CF_LAST_IO));
+            && !(s->tb->cflags & CF_LAST_IO)
+            && !(s->tb->flags & FLAG_MASK_PER));
 }
 
 static void account_noninline_branch(DisasContext *s, int cc_op)
@@ -5234,6 +5235,21 @@ static ExitStatus translate_one(CPUS390XState *env, DisasContext *s)
         tcg_temp_free_i64(o.addr1);
     }
 
+#ifndef CONFIG_USER_ONLY
+    if (s->tb->flags & FLAG_MASK_PER) {
+        /* An exception might be triggered, save PSW if not already done.  */
+        if (ret == NO_EXIT || ret == EXIT_PC_STALE) {
+            tcg_gen_movi_i64(psw_addr, s->next_pc);
+        }
+
+        /* Save off cc.  */
+        update_cc_op(s);
+
+        /* Call the helper to check for a possible PER exception.  */
+        gen_helper_per_check_exception(cpu_env);
+    }
+#endif
+
     /* Advance to the next instruction.  */
     s->pc = s->next_pc;
     return ret;