uclinux-2008R1-RC8(bf561)到VDSP5的移植（9）：bf53x_relocate_l1_mem

 

  

在uclinux初始化的时候有一段代码：

       /* Put The Code for PLL Programming and SDRAM Programming in L1 ISRAM */

       call _bf53x_relocate_l1_mem;

bf53x_relocate_l1_mem这个函数的实现在arch/blackfin/kernel/setup.c中，其作用是将设置SDRAM和PLL的代码从SDRAM或者Flash复制到L1中，如下所示：

 

void __init bf53x_relocate_l1_mem(void)

{

     unsigned long l1_code_length;

     unsigned long l1_data_a_length;

     unsigned long l1_data_b_length;

 

     l1_code_length = _etext_l1 - _stext_l1;

     if (l1_code_length > L1_CODE_LENGTH)

         l1_code_length = L1_CODE_LENGTH;

     /* cannot complain as printk is not available as yet.

      * But we can continue booting and complain later!

      */

 

     /* Copy _stext_l1 to _etext_l1 to L1 instruction SRAM */

     dma_memcpy(_stext_l1, _l1_lma_start, l1_code_length);

 

     l1_data_a_length = _ebss_l1 - _sdata_l1;

     if (l1_data_a_length > L1_DATA_A_LENGTH)

         l1_data_a_length = L1_DATA_A_LENGTH;

 

     /* Copy _sdata_l1 to _ebss_l1 to L1 data bank A SRAM */

     dma_memcpy(_sdata_l1, _l1_lma_start + l1_code_length, l1_data_a_length);

 

     l1_data_b_length = _ebss_b_l1 - _sdata_b_l1;

     if (l1_data_b_length > L1_DATA_B_LENGTH)

         l1_data_b_length = L1_DATA_B_LENGTH;

 

     /* Copy _sdata_b_l1 to _ebss_b_l1 to L1 data bank B SRAM */

     dma_memcpy(_sdata_b_l1, _l1_lma_start + l1_code_length +

              l1_data_a_length, l1_data_b_length);

 

}

 

但是由于我使用了方式1进行启动，且在LDF文件中直接将这部分代码放在了L1中，因此并不需要再复制一次，所以直接注释掉这行语句，即不调用bf53x_relocate_l1_mem这个函数。