ppc: Add POWER8 IAMR register

With appropriate AMR-like masks. Not actually used by the translation
logic at that point
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
[clg: changed spr_register_hv(SPR_IAMR) to spr_register_kvm_hv(SPR_IAMR)
      changed gen_spr_amr() prototype ]
Signed-off-by: NCédric Le Goater <clg@fr.ibm.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

target-ppc/cpu.h

@@ -1360,6 +1360,7 @@ static inline int cpu_mmu_index (CPUPPCState *env, bool ifetch)
 #define SPR_BOOKE_CSRR0       (0x03A)
 #define SPR_BOOKE_CSRR1       (0x03B)
 #define SPR_BOOKE_DEAR        (0x03D)
+#define SPR_IAMR              (0x03D)
 #define SPR_BOOKE_ESR         (0x03E)
 #define SPR_BOOKE_IVPR        (0x03F)
 #define SPR_MPC_EIE           (0x050)

target-ppc/translate_init.c

@@ -1126,9 +1126,39 @@ static void spr_write_uamor(DisasContext *ctx, int sprn, int gprn)
     tcg_temp_free(t1);
     tcg_temp_free(t2);
 }
+
+static void spr_write_iamr(DisasContext *ctx, int sprn, int gprn)
+{
+    TCGv t0 = tcg_temp_new();
+    TCGv t1 = tcg_temp_new();
+    TCGv t2 = tcg_temp_new();
+
+    /* Note, the HV=1 case is handled earlier by simply using
+     * spr_write_generic for HV mode in the SPR table
+     */
+
+    /* Build insertion mask into t1 based on context */
+    gen_load_spr(t1, SPR_AMOR);
+
+    /* Mask new bits into t2 */
+    tcg_gen_and_tl(t2, t1, cpu_gpr[gprn]);
+
+    /* Load AMR and clear new bits in t0 */
+    gen_load_spr(t0, SPR_IAMR);
+    tcg_gen_andc_tl(t0, t0, t1);
+
+    /* Or'in new bits and write it out */
+    tcg_gen_or_tl(t0, t0, t2);
+    gen_store_spr(SPR_IAMR, t0);
+    spr_store_dump_spr(SPR_IAMR);
+
+    tcg_temp_free(t0);
+    tcg_temp_free(t1);
+    tcg_temp_free(t2);
+}
 #endif /* CONFIG_USER_ONLY */
 
-static void gen_spr_amr (CPUPPCState *env)
+static void gen_spr_amr(CPUPPCState *env, bool has_iamr)
 {
 #ifndef CONFIG_USER_ONLY
     /* Virtual Page Class Key protection */
@@ -1154,6 +1184,13 @@ static void gen_spr_amr (CPUPPCState *env)
                     SPR_NOACCESS, SPR_NOACCESS,
                     &spr_read_generic, &spr_write_generic,
                     0);
+    if (has_iamr) {
+        spr_register_kvm_hv(env, SPR_IAMR, "IAMR",
+                            SPR_NOACCESS, SPR_NOACCESS,
+                            &spr_read_generic, &spr_write_iamr,
+                            &spr_read_generic, &spr_write_generic,
+                            KVM_REG_PPC_IAMR, 0);
+    }
 #endif /* !CONFIG_USER_ONLY */
 }
 #endif /* TARGET_PPC64 */
@@ -8000,7 +8037,7 @@ static void init_proc_book3s_64(CPUPPCState *env, int version)
     case BOOK3S_CPU_POWER7:
     case BOOK3S_CPU_POWER8:
         gen_spr_book3s_ids(env);
-        gen_spr_amr(env);
+        gen_spr_amr(env, version >= BOOK3S_CPU_POWER8);
         gen_spr_book3s_purr(env);
         env->ci_large_pages = true;
         break;