From 1ae8e5f53ae0563d4145b4364c89dd4a82a071de Mon Sep 17 00:00:00 2001
From: Denis Drakhnia <numas13@gmail.com>
Date: Fri, 12 Jul 2024 12:14:42 +0300
Subject: [PATCH] e2k: disable probe page cache by default

---
 linux-user/e2k/cpu_loop.c |  4 +++-
 target/e2k/cpu.c          |  1 +
 target/e2k/cpu.h          |  3 +++
 target/e2k/helper_sm.c    | 13 +++++++++----
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/linux-user/e2k/cpu_loop.c b/linux-user/e2k/cpu_loop.c
index d3bf98b027..60b0a65fd6 100644
--- a/linux-user/e2k/cpu_loop.c
+++ b/linux-user/e2k/cpu_loop.c
@@ -130,7 +130,9 @@ void cpu_loop(CPUE2KState *env)
                     }
 
                     if (ret == 0) {
-                        e2k_clear_probe_page_cache(num);
+                        if (env->enable_pagecache) {
+                            e2k_clear_probe_page_cache(num);
+                        }
                         ret = do_syscall(env, num, args[1], args[2], args[3],
                             args[4], args[5], args[6], args[7], args[8]);
                     }
diff --git a/target/e2k/cpu.c b/target/e2k/cpu.c
index 2e935cdf44..1e8a40b689 100644
--- a/target/e2k/cpu.c
+++ b/target/e2k/cpu.c
@@ -262,6 +262,7 @@ static struct TCGCPUOps e2k_tcg_ops = {
 static Property e2k_cpu_properties[] = {
     DEFINE_PROP_BOOL("force_save_alc_dst", E2KCPU, env.force_save_alc_dst, false),
     DEFINE_PROP_BOOL("tags", E2KCPU, env.enable_tags, false),
+    DEFINE_PROP_BOOL("pagecache", E2KCPU, env.enable_pagecache, false),
     DEFINE_PROP_END_OF_LIST()
 };
 
diff --git a/target/e2k/cpu.h b/target/e2k/cpu.h
index 93977e0bed..d78e4ba039 100644
--- a/target/e2k/cpu.h
+++ b/target/e2k/cpu.h
@@ -936,6 +936,9 @@ typedef struct CPUArchState {
     /* Enable tags handling.
      * Default: false */
     bool enable_tags;
+    /* Enable page cache for speculative memory accesses.
+     * Default: false */
+    bool enable_pagecache;
 
     struct e2k_def_t def;
 
diff --git a/target/e2k/helper_sm.c b/target/e2k/helper_sm.c
index 81793f82af..52d86fafeb 100644
--- a/target/e2k/helper_sm.c
+++ b/target/e2k/helper_sm.c
@@ -20,15 +20,20 @@
 static bool e2k_probe_access_cached(CPUE2KState *env, target_ulong page, int flags)
 {
     int index = (page >> TARGET_PAGE_BITS) & (TARGET_PROBE_CACHE_SIZE - 1);
+    uint8_t page_flags;
 
-    if (env->probe_cache_page[index] == page) {
+    if (env->enable_pagecache && env->probe_cache_page[index] == page) {
         return (env->probe_cache_flags[index] & flags) == flags;
     }
 
-    env->probe_cache_page[index] = page;
-    env->probe_cache_flags[index] = page_get_flags(page);
+    page_flags = page_get_flags(page);
 
-    return (env->probe_cache_flags[index] & flags) == flags;
+    if (env->enable_pagecache) {
+        env->probe_cache_page[index] = page;
+        env->probe_cache_flags[index] = page_flags;
+    }
+
+    return (page_flags & flags) == flags;
 }
 
 static bool e2k_probe_access(CPUE2KState *env, target_ulong addr, int size, int flags)