Merge pull request #1743 from lvgl/dcache_cb

lv_disp: add `clean_dcache_cb` callback

CHANGELOG.md

@@ -9,6 +9,7 @@
 - Add `lv_font_load()` function - Loads a `lv_font_t` object from a binary font file
 - Add `lv_font_free()` function - Frees the memory allocated by the `lv_font_load()` function
 - Add style caching to reduce acces time of properties with default value
+- Add `clean_dcache_cb` and `lv_disp_clean_dcache` to enable users to use their own cache management function
 
 ### Bugfixes
 - Fix color bleeding on border drawing

src/lv_core/lv_disp.c

@@ -352,6 +352,21 @@ void lv_disp_trig_activity(lv_disp_t * disp)
     disp->last_activity_time = lv_tick_get();
 }
 
+/**
+ * Clean any CPU cache that is related to the display.
+ * @param disp pointer to an display (NULL to use the default display)
+ */
+void lv_disp_clean_dcache(lv_disp_t * disp)
+{
+    if(!disp) disp = lv_disp_get_default();
+    if(!disp) {
+      LV_LOG_WARN("lv_disp_clean_dcache: no display registered");
+      return;
+    }
+
+    if(disp->driver.clean_dcache_cb)
+      disp->driver.clean_dcache_cb(&disp->driver);
+}
 
 /**
  * Get a pointer to the screen refresher task to

src/lv_core/lv_disp.h

@@ -133,6 +133,12 @@ uint32_t lv_disp_get_inactive_time(const lv_disp_t * disp);
  */
 void lv_disp_trig_activity(lv_disp_t * disp);
 
+/**
+ * Clean any CPU cache that is related to the display.
+ * @param disp pointer to an display (NULL to use the default display)
+ */
+void lv_disp_clean_dcache(lv_disp_t * disp);
+
 /**
  * Get a pointer to the screen refresher task to
  * modify its parameters with `lv_task_...` functions.

src/lv_gpu/lv_gpu_stm32_dma2d.c

@@ -7,6 +7,7 @@
  *      INCLUDES
  *********************/
 #include "lv_gpu_stm32_dma2d.h"
+#include "../lv_core/lv_disp.h"
 #include "../lv_core/lv_refr.h"
 
 #if LV_USE_GPU_STM32_DMA2D
@@ -216,11 +217,10 @@ void lv_gpu_stm32_dma2d_blend(lv_color_t * buf, lv_coord_t buf_w, const lv_color
 
 static void invalidate_cache(void)
 {
-#if __DCACHE_PRESENT
-    if(SCB->CCR & (uint32_t)SCB_CCR_DC_Msk) {
+    lv_disp_t * disp = _lv_refr_get_disp_refreshing();
+    if(disp->driver.clean_dcache_cb) disp->driver.clean_dcache_cb(&disp->driver);
+    else
         SCB_CleanInvalidateDCache();
-    }
-#endif
 }
 
 static void dma2d_wait(void)

src/lv_hal/lv_hal_disp.h

@@ -111,6 +111,9 @@ typedef struct _disp_drv_t {
      * User can execute very simple tasks here or yield the task */
     void (*wait_cb)(struct _disp_drv_t * disp_drv);
 
+    /** OPTIONAL: Called when lvgl needs any CPU cache that affects rendering to be cleaned */
+    void (*clean_dcache_cb)(struct _disp_drv_t * disp_drv);
+
 #if LV_USE_GPU
     /** OPTIONAL: Blend two memories using opacity (GPU only)*/
     void (*gpu_blend_cb)(struct _disp_drv_t * disp_drv, lv_color_t * dest, const lv_color_t * src, uint32_t length,