STM32【HAL库】使用外部SRAM程序

#include <board.h>

#ifdef BSP_USING_SRAM
#include <drv_common.h>
#include <rtthread.h>
#include <rtdevice.h>

#define DBG_TAG "drv_exsram"
#define DBG_LVL DBG_LOG
#include <rtdbg.h>

#define RAM_HEAP_EX_START           (0x68000000)
#define RAM_HEAP_EX_SIZE            (1024 * 1024)
#define RAM_HEAP_EX_END             (RAM_HEAP_EX_START + RAM_HEAP_EX_SIZE)

/* 注意：SRAM 句柄不能为局部变量 */
SRAM_HandleTypeDef SRAM_Handler;    // SRAM句柄

#ifdef RT_USING_MEMHEAP_AS_HEAP
static struct rt_memheap system_heap;
#endif


/**
  * @brief SRAM 初始化
  * @retval None
  */
static int system_sram_init(void)
{
	int result = RT_EOK;
	
    FSMC_NORSRAM_TimingTypeDef FSMC_ReadWriteTim;

    /*----------------------------------------- 使能时钟 -----------------------------------------*/
    __HAL_RCC_GPIOD_CLK_ENABLE();           // 使能GPIOD时钟
    __HAL_RCC_GPIOE_CLK_ENABLE();           // 使能GPIOE时钟
    __HAL_RCC_GPIOF_CLK_ENABLE();           // 使能GPIOF时钟
    __HAL_RCC_GPIOG_CLK_ENABLE();           // 使能GPIOG时钟

    /*----------------------------------------- 配置 SRAM -----------------------------------------*/
    SRAM_Handler.Instance = FSMC_NORSRAM_DEVICE;
    SRAM_Handler.Extended = FSMC_NORSRAM_EXTENDED_DEVICE;
    SRAM_Handler.Init.NSBank = FSMC_NORSRAM_BANK3;                          // 使用NE3
    SRAM_Handler.Init.DataAddressMux = FSMC_DATA_ADDRESS_MUX_DISABLE;       // 地址/数据线不复用
    SRAM_Handler.Init.MemoryType = FSMC_MEMORY_TYPE_SRAM;                   // SRAM
    SRAM_Handler.Init.MemoryDataWidth = FSMC_NORSRAM_MEM_BUS_WIDTH_16;      // 16位数据宽度
    SRAM_Handler.Init.BurstAccessMode = FSMC_BURST_ACCESS_MODE_DISABLE;     // 是否使能突发访问,仅对同步突发存储器有效,此处未用到
    SRAM_Handler.Init.WaitSignalPolarity = FSMC_WAIT_SIGNAL_POLARITY_LOW;   // 等待信号的极性,仅在突发模式访问下有用
    SRAM_Handler.Init.WaitSignalActive = FSMC_WAIT_TIMING_BEFORE_WS;        // 存储器是在等待周期之前的一个时钟周期还是等待周期期间使能NWAIT
    SRAM_Handler.Init.WriteOperation = FSMC_WRITE_OPERATION_ENABLE;         // 存储器写使能
    SRAM_Handler.Init.WaitSignal = FSMC_WAIT_SIGNAL_DISABLE;                // 等待使能位,此处未用到
    SRAM_Handler.Init.ExtendedMode = FSMC_EXTENDED_MODE_DISABLE;            // 读写使用相同的时序
    SRAM_Handler.Init.AsynchronousWait = FSMC_ASYNCHRONOUS_WAIT_DISABLE;    // 是否使能同步传输模式下的等待信号,此处未用到
    SRAM_Handler.Init.WriteBurst = FSMC_WRITE_BURST_DISABLE;                // 禁止突发写

    /*----------------------------------------- FSMC 读写时序控制 -----------------------------------------*/
    FSMC_ReadWriteTim.AddressSetupTime = 0x00;          // 地址建立时间（ADDSET）为1个HCLK 1/72M = 13.8ns
    FSMC_ReadWriteTim.AddressHoldTime = 0x00;           // 地址保持时间（ADDHLD）模式A未用到
    FSMC_ReadWriteTim.DataSetupTime = 0x03;             // 数据保存时间为3个HCLK = 4*13.8 = 55ns
    FSMC_ReadWriteTim.BusTurnAroundDuration = 0X00;
    FSMC_ReadWriteTim.CLKDivision = 0X00;
    FSMC_ReadWriteTim.DataLatency = 0X00;
    FSMC_ReadWriteTim.AccessMode = FSMC_ACCESS_MODE_A;  // 模式A

    if (HAL_SRAM_Init(&SRAM_Handler, &FSMC_ReadWriteTim, &FSMC_ReadWriteTim) != HAL_OK)
	{
		LOG_E("SDRAM init failed!");
        result = -RT_ERROR;
	}
	else
    {
#ifdef RT_USING_MEMHEAP_AS_HEAP
        /* If RT_USING_MEMHEAP_AS_HEAP is enabled, SDRAM is initialized to the heap */
		rt_memheap_init(&system_heap, "sdram", (void *)RAM_HEAP_EX_START, RAM_HEAP_EX_SIZE);
#else
        rt_system_heap_init((void *)RAM_HEAP_EX_START, (void *)RAM_HEAP_EX_END);
#endif
    }
	
	return result;
}

INIT_BOARD_EXPORT(system_sram_init);

#endif /* BSP_USING_SRAM */