video: allow allocating buffers via the mem sw attr heap allocator

Video buffers being often quite big, it might not be possible to
allocate them from the default heap. For that reason, rely on the
mem sw attr heap allocator in order to design from where to
allocate buffers using which attributes.

Signed-off-by: Alain Volmat <[email protected]>

Author: Alain Volmat

drivers/video/Kconfig

@@ -58,6 +58,20 @@ config VIDEO_I2C_RETRY_NUM
 	  The default is to not retry. Board configuration files or user project can then
 	  use the number of retries that matches their situation.
 
+config VIDEO_BUFFER_USE_MEM_ATTR_HEAP
+	bool "Use mem attr api for video buffer"
+	default n
+
+config VIDEO_BUFFER_MEM_SW_ATTRIBUTE
+	int "Mem SW attribute for video buffer"
+	depends on VIDEO_BUFFER_USE_MEM_ATTR_HEAP
+	default 1
+	help
+	  Mem SW attribute for video buffer:
+	  1: ATTR_SW_ALLOC_CACHE
+	  2: ATTR_SW_ALLOC_NON_CACHE
+	  4: ATTR_SW_ALLOC_DMA
+
 source "drivers/video/Kconfig.esp32_dvp"
 
 source "drivers/video/Kconfig.mcux_csi"

drivers/video/video_common.c

@@ -26,6 +26,14 @@ LOG_MODULE_REGISTER(video_common, CONFIG_VIDEO_LOG_LEVEL);
 #define VIDEO_COMMON_HEAP_ALLOC(align, size, timeout)                                              \
 	shared_multi_heap_aligned_alloc(CONFIG_VIDEO_BUFFER_SMH_ATTRIBUTE, align, size)
 #define VIDEO_COMMON_FREE(block) shared_multi_heap_free(block)
+#elif defined(CONFIG_VIDEO_BUFFER_USE_MEM_ATTR_HEAP)
+#include <zephyr/mem_mgmt/mem_attr_heap.h>
+#include <zephyr/dt-bindings/memory-attr/memory-attr.h>
+
+#define VIDEO_COMMON_HEAP_ALLOC(align, size, timeout)                                              \
+	mem_attr_heap_aligned_alloc((CONFIG_VIDEO_BUFFER_MEM_SW_ATTRIBUTE <<	\
+				    DT_MEM_SW_ATTR_SHIFT), align, size)
+#define VIDEO_COMMON_FREE(block) mem_attr_heap_free(block)
 #else
 K_HEAP_DEFINE(video_buffer_pool, CONFIG_VIDEO_BUFFER_POOL_SZ_MAX*CONFIG_VIDEO_BUFFER_POOL_NUM_MAX);
 #define VIDEO_COMMON_HEAP_ALLOC(align, size, timeout)                                              \
@@ -47,6 +55,9 @@ struct video_buffer *video_buffer_aligned_alloc(size_t size, size_t align, k_tim
 	struct mem_block *block;
 	int i;
 
+#if defined(CONFIG_VIDEO_BUFFER_USE_MEM_ATTR_HEAP)
+	mem_attr_heap_pool_init();
+#endif
 	/* find available video buffer */
 	for (i = 0; i < ARRAY_SIZE(video_buf); i++) {
 		if (video_buf[i].buffer == NULL) {