From 7faa66aaf88fd0acc35c86bf56d688eeeee841c7 Mon Sep 17 00:00:00 2001
From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
Date: Fri, 16 Jun 2017 17:21:05 +0200
Subject: [PATCH] target-microblaze: Introduce a use-barrel property

Introduce a use-barrel property making barrel shifter instructions
optional.

Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
---
 target/microblaze/cpu.c       | 9 +++++----
 target/microblaze/cpu.h       | 1 +
 target/microblaze/translate.c | 2 +-
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/target/microblaze/cpu.c b/target/microblaze/cpu.c
index 982cb61dd6..bae47b51fa 100644
--- a/target/microblaze/cpu.c
+++ b/target/microblaze/cpu.c
@@ -150,8 +150,7 @@ static void mb_cpu_realizefn(DeviceState *dev, Error **errp)
 
     qemu_init_vcpu(cs);
 
-    env->pvr.regs[0] = PVR0_USE_BARREL_MASK \
-                       | PVR0_USE_DIV_MASK \
+    env->pvr.regs[0] = PVR0_USE_DIV_MASK \
                        | PVR0_USE_HW_MUL_MASK \
                        | PVR0_USE_EXC_MASK \
                        | PVR0_USE_ICACHE_MASK \
@@ -162,7 +161,6 @@ static void mb_cpu_realizefn(DeviceState *dev, Error **errp)
                         | PVR2_I_LMB_MASK \
                         | PVR2_USE_MSR_INSTR \
                         | PVR2_USE_PCMP_INSTR \
-                        | PVR2_USE_BARREL_MASK \
                         | PVR2_USE_DIV_MASK \
                         | PVR2_USE_HW_MUL_MASK \
                         | PVR2_USE_MUL64_MASK \
@@ -182,13 +180,15 @@ static void mb_cpu_realizefn(DeviceState *dev, Error **errp)
 
     env->pvr.regs[0] |= (cpu->cfg.stackprot ? PVR0_SPROT_MASK : 0) |
                         (cpu->cfg.use_fpu ? PVR0_USE_FPU_MASK : 0) |
+                        (cpu->cfg.use_barrel ? PVR0_USE_BARREL_MASK : 0) |
                         (cpu->cfg.use_mmu ? PVR0_USE_MMU_MASK : 0) |
                         (cpu->cfg.endi ? PVR0_ENDI_MASK : 0) |
                         (version_code << PVR0_VERSION_SHIFT) |
                         (cpu->cfg.pvr == C_PVR_FULL ? PVR0_PVR_FULL_MASK : 0);
 
     env->pvr.regs[2] |= (cpu->cfg.use_fpu ? PVR2_USE_FPU_MASK : 0) |
-                        (cpu->cfg.use_fpu > 1 ? PVR2_USE_FPU2_MASK : 0);
+                        (cpu->cfg.use_fpu > 1 ? PVR2_USE_FPU2_MASK : 0) |
+                        (cpu->cfg.use_barrel ? PVR2_USE_BARREL_MASK : 0);
 
     env->pvr.regs[5] |= cpu->cfg.dcache_writeback ?
                                         PVR5_DCACHE_WRITEBACK_MASK : 0;
@@ -235,6 +235,7 @@ static Property mb_properties[] = {
      *                  are enabled
      */
     DEFINE_PROP_UINT8("use-fpu", MicroBlazeCPU, cfg.use_fpu, 2),
+    DEFINE_PROP_BOOL("use-barrel", MicroBlazeCPU, cfg.use_barrel, true),
     DEFINE_PROP_BOOL("use-mmu", MicroBlazeCPU, cfg.use_mmu, true),
     DEFINE_PROP_BOOL("dcache-writeback", MicroBlazeCPU, cfg.dcache_writeback,
                      false),
diff --git a/target/microblaze/cpu.h b/target/microblaze/cpu.h
index 68c33e83e4..2a4a65a9e0 100644
--- a/target/microblaze/cpu.h
+++ b/target/microblaze/cpu.h
@@ -298,6 +298,7 @@ struct MicroBlazeCPU {
         bool stackprot;
         uint32_t base_vectors;
         uint8_t use_fpu;
+        bool use_barrel;
         bool use_mmu;
         bool dcache_writeback;
         bool endi;
diff --git a/target/microblaze/translate.c b/target/microblaze/translate.c
index 0bb609513c..26b221cec8 100644
--- a/target/microblaze/translate.c
+++ b/target/microblaze/translate.c
@@ -665,7 +665,7 @@ static void dec_barrel(DisasContext *dc)
 
     if ((dc->tb_flags & MSR_EE_FLAG)
           && (dc->cpu->env.pvr.regs[2] & PVR2_ILL_OPCODE_EXC_MASK)
-          && !(dc->cpu->env.pvr.regs[0] & PVR0_USE_BARREL_MASK)) {
+          && !dc->cpu->cfg.use_barrel) {
         tcg_gen_movi_tl(cpu_SR[SR_ESR], ESR_EC_ILLEGAL_OP);
         t_gen_raise_exception(dc, EXCP_HW_EXCP);
         return;