From 6bb78e4573667f59d246e25e433c27bc3430757c Mon Sep 17 00:00:00 2001
From: armando <douyiwen@espressif.com>
Date: Wed, 26 Mar 2025 16:07:17 +0800
Subject: [PATCH] fix(cache): disable branch predictor when cache freeze

---
 components/esp_mm/esp_cache.c                 | 15 +++++++++
 .../include/esp_private/esp_cache_private.h   | 33 ++++++++++++++++++-
 components/spi_flash/cache_utils.c            | 13 ++------
 3 files changed, 50 insertions(+), 11 deletions(-)

diff --git a/components/esp_mm/esp_cache.c b/components/esp_mm/esp_cache.c
index 161df6d28a..26cacdf134 100644
--- a/components/esp_mm/esp_cache.c
+++ b/components/esp_mm/esp_cache.c
@@ -16,6 +16,7 @@
 #include "hal/mmu_hal.h"
 #include "hal/cache_hal.h"
 #include "hal/cache_ll.h"
+#include "esp_cpu.h"
 #include "esp_cache.h"
 #include "esp_private/esp_cache_private.h"
 #include "esp_private/critical_section.h"
@@ -95,6 +96,10 @@ esp_err_t esp_cache_msync(void *addr, size_t size, int flags)
 
 void esp_cache_suspend_ext_mem_cache(void)
 {
+#if SOC_BRANCH_PREDICTOR_SUPPORTED
+    //branch predictor will start cache request as well
+    esp_cpu_branch_prediction_disable();
+#endif
 #if (CONFIG_SPIRAM && SOC_CACHE_INTERNAL_MEM_VIA_L1CACHE)
     /**
      * before suspending the external mem cache, writeback internal mem cache content back to external mem cache
@@ -108,11 +113,18 @@ void esp_cache_suspend_ext_mem_cache(void)
 void esp_cache_resume_ext_mem_cache(void)
 {
     cache_hal_resume(CACHE_LL_LEVEL_EXT_MEM, CACHE_TYPE_ALL);
+#if SOC_BRANCH_PREDICTOR_SUPPORTED
+    esp_cpu_branch_prediction_enable();
+#endif
 }
 
 #if SOC_CACHE_FREEZE_SUPPORTED
 void esp_cache_freeze_ext_mem_cache(void)
 {
+#if SOC_BRANCH_PREDICTOR_SUPPORTED
+    //branch predictor will start cache request as well
+    esp_cpu_branch_prediction_disable();
+#endif
 #if (CONFIG_SPIRAM && SOC_CACHE_INTERNAL_MEM_VIA_L1CACHE)
     /**
      * before freezing the external mem cache, writeback internal mem cache content back to external mem cache
@@ -126,6 +138,9 @@ void esp_cache_freeze_ext_mem_cache(void)
 void esp_cache_unfreeze_ext_mem_cache(void)
 {
     cache_hal_unfreeze(CACHE_LL_LEVEL_EXT_MEM, CACHE_TYPE_ALL);
+#if SOC_BRANCH_PREDICTOR_SUPPORTED
+    esp_cpu_branch_prediction_enable();
+#endif
 }
 #endif  //#if SOC_CACHE_FREEZE_SUPPORTED
 
diff --git a/components/esp_mm/include/esp_private/esp_cache_private.h b/components/esp_mm/include/esp_private/esp_cache_private.h
index 3f28554220..39f1cf9e7e 100644
--- a/components/esp_mm/include/esp_private/esp_cache_private.h
+++ b/components/esp_mm/include/esp_private/esp_cache_private.h
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -7,6 +7,7 @@
 
 #include <stdlib.h>
 #include <stdint.h>
+#include "soc/soc_caps.h"
 #include "esp_err.h"
 #include "esp_bit_defs.h"
 #include "esp_heap_caps.h"
@@ -15,6 +16,36 @@
 extern "C" {
 #endif
 
+/**
+ * @brief Suspend external memory cache
+ *
+ * @note This API is only for internal usage, no thread safety guaranteed
+ */
+void esp_cache_suspend_ext_mem_cache(void);
+
+/**
+ * @brief Resume external memory cache
+ *
+ * @note This API is only for internal usage, no thread safety guaranteed
+ */
+void esp_cache_resume_ext_mem_cache(void);
+
+#if SOC_CACHE_FREEZE_SUPPORTED
+/**
+ * @brief Freeze external memory cache
+ *
+ * @note This API is only for internal usage, no thread safety guaranteed
+ */
+void esp_cache_freeze_ext_mem_cache(void);
+
+/**
+ * @brief Unfreeze external memory cache
+ *
+ * @note This API is only for internal usage, no thread safety guaranteed
+ */
+void esp_cache_unfreeze_ext_mem_cache(void);
+#endif
+
 /**
  * @brief Helper function for malloc a cache aligned data memory buffer
  *
diff --git a/components/spi_flash/cache_utils.c b/components/spi_flash/cache_utils.c
index ce4c57c409..f2d57d998a 100644
--- a/components/spi_flash/cache_utils.c
+++ b/components/spi_flash/cache_utils.c
@@ -58,11 +58,11 @@
 #include "esp_memory_utils.h"
 #include "esp_intr_alloc.h"
 #include "spi_flash_override.h"
+#include "esp_private/esp_cache_private.h"
 #include "esp_private/cache_utils.h"
 #include "esp_private/spi_flash_os.h"
 #include "esp_private/freertos_idf_additions_priv.h"
 #include "esp_log.h"
-#include "esp_cpu.h"
 
 static __attribute__((unused)) const char *TAG = "cache";
 
@@ -364,19 +364,12 @@ void IRAM_ATTR spi_flash_enable_cache(uint32_t cpuid)
 
 void IRAM_ATTR spi_flash_disable_cache(uint32_t cpuid, uint32_t *saved_state)
 {
-#if SOC_BRANCH_PREDICTOR_SUPPORTED
-    //branch predictor will start cache request as well
-    esp_cpu_branch_prediction_disable();
-#endif
-    cache_hal_suspend(CACHE_LL_LEVEL_EXT_MEM, CACHE_TYPE_ALL);
+    esp_cache_suspend_ext_mem_cache();
 }
 
 void IRAM_ATTR spi_flash_restore_cache(uint32_t cpuid, uint32_t saved_state)
 {
-    cache_hal_resume(CACHE_LL_LEVEL_EXT_MEM, CACHE_TYPE_ALL);
-#if SOC_BRANCH_PREDICTOR_SUPPORTED
-    esp_cpu_branch_prediction_enable();
-#endif
+    esp_cache_resume_ext_mem_cache();
 }
 
 bool IRAM_ATTR spi_flash_cache_enabled(void)