h7 backupRAM写保护导致的hardfault

Superusrss

使用stm32H750时候使用backupram，已配置MPU如下

[C] 纯文本查看 复制代码

    /* AXI SRAM MPU set to Write back, Read allocate，Write allocate */
    MPU_InitStruct.Enable = MPU_REGION_ENABLE;
    MPU_InitStruct.BaseAddress = 0x24000000;
    MPU_InitStruct.Size = MPU_REGION_SIZE_512KB;
    MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
    MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
    MPU_InitStruct.IsCacheable = MPU_ACCESS_CACHEABLE;
    MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
    MPU_InitStruct.Number = MPU_REGION_NUMBER0;
    MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
    MPU_InitStruct.SubRegionDisable = 0x00;
    MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_ENABLE;

    HAL_MPU_ConfigRegion(&MPU_InitStruct);

		// RAM D2
		MPU_InitStruct.BaseAddress = 0x30000000;
    MPU_InitStruct.Size = MPU_REGION_SIZE_512KB;
		HAL_MPU_ConfigRegion(&MPU_InitStruct);

		// RAM D3
		MPU_InitStruct.BaseAddress = 0x38000000;
    MPU_InitStruct.Size = MPU_REGION_SIZE_64KB;
		HAL_MPU_ConfigRegion(&MPU_InitStruct);

		/* BackUP RAM set to NORMAL, NO Read allocate，NO Write allocate */
		MPU_InitStruct.BaseAddress = 0x38800000;
    MPU_InitStruct.Size = MPU_REGION_SIZE_4KB;
		MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
    MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
		MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL1;
		HAL_MPU_ConfigRegion(&MPU_InitStruct);

然后lvgl库中若使用DMA2D加速，会调用SCB_CleanInvalidateDCache，若先前调用HAL_PWR_DisableBkUpAccess则会导致hardfault。

但是我已经配置备份域NOT_BUFFERABLE NOT_CACHEABLE了啊

eric2013

没太理解楼主意思，不禁止备份RAM正常吗

HAL_PWR_DisableBkUpAccess

Superusrss

eric2013 发表于 2024-9-17 09:56
没太理解楼主意思，不禁止备份RAM正常吗

HAL_PWR_DisableBkUpAccess

不禁止正常，但是backupram本身就需要保护吧，所以每次修改配置时候都是HAL_PWR_EnableBkUpAccess(); 修改完后 HAL_PWR_DisableBkUpAccess();

eric2013

Superusrss 发表于 2024-9-17 10:01
不禁止正常，但是backupram本身就需要保护吧，所以每次修改配置时候都是HAL_PWR_EnableBkUpAccess(); 修 ...

你不对这个0x38800000区域做MPU设置，是否正常。

还是不行的话，考虑一直开启就行了。按说这个和MPU设置没什么关系