02.07.2013 Views

Uboot中start.S源码的指令级的详尽解析

Uboot中start.S源码的指令级的详尽解析

Uboot中start.S源码的指令级的详尽解析

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下面就需要好好解释一番了。<br />

具体解释之前,先贴上 ARM7 和 ARM9 的流水线的区别和联系:<br />

图表 26 ARM7 三级流水线 vs ARM9 五级流水线<br />

图表 27 ARM7 三级流水线到 ARM9 五级流水线的映射<br />

下面开始对为何 ARM9 也是 PC=PC+8 进行解释。<br />

先列出 ARM9 的五级流水线的示例:

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