STM32H745 LTDC define 3 framebuffer in SDRAM
Hello,
I'm using STM32H745XIH(M7 side) & interfacing 1280X800 LCD-TFT with STemWin library.
In MPU_Config I've defined 2 region as NON_CACHE(8MB) and CACHE(8MB) in SDRAM(Starting address 0xC0000000).
Framebuffer define in NON_CACHE region & aGuiDataMemory define in CACHE region.
For 2 framebuffer(with ARGB8888) it works fine but some lag found in screen while transition.
So, define NUM_BUFFERS=3 in LCDConf.c, and extend the NON_CACHE region to 16MB & also define SDRAM LENGTH = 24M in linker script. Now my program crashes at run time when i try to access CACHE memory(memset aGuiDataMemory in GUI_X_Config function).
Debugging code gives Hardfault at this point.
When I change linker script CACHE start address from 0xC00000(for 2 buffer configuration) to 0x1000000(for 3 buffer configuration) program crashes as above mention.
In Build Analyzer,
2 framebuffer consumes 7.8125 MB
3 framebuffer consumes 11.71875 MB
In linker script:
MEMORY
{
SDRAM (xrw) : ORIGIN = 0xC0000000, LENGTH = 24M
}
.sdram (NOLOAD):
{
_ssdram = .;
/* 16MB NonCache */
. = ALIGN(4);
_ssdram_ncache = .; /* create a global symbol at sdram start */
*(.sdram_ncache)
. = ALIGN(4);
_esdram_ncache = .; /* create a global symbol at sdram end */
/* 8MB Cache */
. = ALIGN(4);
/* . = 0xC00000; Keep offset of around 4MB as per https://www.keil.com/support/docs/3777.htm */
_ssdram_cache = .; /* create a global symbol at sdram_gui start */
*(.sdram_cache)
. = ALIGN(4);
_esdram_cache = .; /* create a global symbol at sdram_gui end */
_esdram = .;
} >SDRAM
In MPU_Config:
void MPU_Config(void)
{
MPU_Region_InitTypeDef MPU_InitStruct = {0};
/* Disables the MPU */
HAL_MPU_Disable();
/* DEFINE NON CACHE AREA */
MPU_InitStruct.Enable = MPU_REGION_ENABLE;
MPU_InitStruct.Number = MPU_REGION_NUMBER1;
MPU_InitStruct.BaseAddress = 0xC0000000;
MPU_InitStruct.Size = MPU_REGION_SIZE_16MB;
MPU_InitStruct.SubRegionDisable = 0x0;
MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL1;
MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
HAL_MPU_ConfigRegion(&MPU_InitStruct);
/** Initializes and configures the Region and the memory to be protected
* Define CACHE AREA
*/
MPU_InitStruct.Enable = MPU_REGION_ENABLE;
MPU_InitStruct.Number = MPU_REGION_NUMBER2;
MPU_InitStruct.BaseAddress = 0xC1000000;
MPU_InitStruct.Size = MPU_REGION_SIZE_8MB;
MPU_InitStruct.SubRegionDisable = 0x0;
MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
MPU_InitStruct.IsCacheable = MPU_ACCESS_CACHEABLE;
MPU_InitStruct.IsBufferable = MPU_ACCESS_BUFFERABLE;
HAL_MPU_ConfigRegion(&MPU_InitStruct);
/* Enables the MPU */
HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);
}
What I am missing here?