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标题:
请高手指教,谢谢~~~
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作者:
yanchunqing2010
时间:
2016-8-13 13:24
标题:
请高手指教,谢谢~~~
想请教下,最后一句为什么是与0x3F取反相与。此例程是USB_HOST_MSC例程下, cppidma.c下面的函数,请高手指教,谢谢~~~
#define DESC_REGION_SIZE (1024 * 20) + SOC_CACHELINE_SIZE_MAX
unsigned int region0DescriptorSpace[DESC_REGION_SIZE];
/*Queue region setup */
/*The Descriptor region address is aligned for SOC_CACHELINE_SIZE_MAX Byte access */
descAddress = (unsigned int)region0DescriptorSpace;
/*Add SOC_CACHELINE_SIZE_MAX to the starting address */
descAddress = descAddress + BYTE_ALIGNMENT;
/*Align the strating adress */
descAddress &= ~0x3F;
作者:
human
时间:
2016-8-22 13:47
该地址要求64位边界对齐
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