[PATCH v2 8/9] ppc/ppc405: Introduce a store helper for SPR_40x_PID

["Cédric Le Goater" <clg@kaod.org>]

The PID SPR of the 405 CPU contains the translation ID of the TLB
which is a 8-bit field. Enforce the mask with a store helper.

Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211222064025.1541490-8-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 target/ppc/spr_tcg.h   | 1 +
 target/ppc/cpu_init.c  | 2 +-
 target/ppc/translate.c | 8 ++++++++
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/target/ppc/spr_tcg.h b/target/ppc/spr_tcg.h
index 64cf5302cb86..89ff111724dc 100644
--- a/target/ppc/spr_tcg.h
+++ b/target/ppc/spr_tcg.h
@@ -89,6 +89,7 @@ void spr_write_40x_dbcr0(DisasContext *ctx, int sprn, int gprn);
 void spr_write_40x_sler(DisasContext *ctx, int sprn, int gprn);
 void spr_write_40x_tcr(DisasContext *ctx, int sprn, int gprn);
 void spr_write_40x_tsr(DisasContext *ctx, int sprn, int gprn);
+void spr_write_40x_pid(DisasContext *ctx, int sprn, int gprn);
 void spr_write_booke_tcr(DisasContext *ctx, int sprn, int gprn);
 void spr_write_booke_tsr(DisasContext *ctx, int sprn, int gprn);
 void spr_read_403_pbr(DisasContext *ctx, int gprn, int sprn);
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index b5e2fde9ec4d..9ef9a1a5ddd5 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -1454,7 +1454,7 @@ static void register_405_sprs(CPUPPCState *env)
     /* MMU */
     spr_register(env, SPR_40x_PID, "PID",
                  SPR_NOACCESS, SPR_NOACCESS,
-                 &spr_read_generic, &spr_write_generic,
+                 &spr_read_generic, &spr_write_40x_pid,
                  0x00000000);
     spr_register(env, SPR_4xx_CCR0, "CCR0",
                  SPR_NOACCESS, SPR_NOACCESS,
diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index eb45f679d34f..cb8ab4d67635 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -890,6 +890,14 @@ void spr_write_40x_tsr(DisasContext *ctx, int sprn, int gprn)
     gen_helper_store_40x_tsr(cpu_env, cpu_gpr[gprn]);
 }
 
+void spr_write_40x_pid(DisasContext *ctx, int sprn, int gprn)
+{
+    TCGv t0 = tcg_temp_new();
+    tcg_gen_andi_tl(t0, cpu_gpr[gprn], 0xFF);
+    gen_store_spr(SPR_40x_PID, t0);
+    tcg_temp_free(t0);
+}
+
 void spr_write_booke_tcr(DisasContext *ctx, int sprn, int gprn)
 {
     gen_icount_io_start(ctx);
-- 
2.31.1