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</o:shapelayout></xml><![endif]--></head><body lang=KO link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hello all,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I'm learning u-boot these days and have a question.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Using qemu model, I could (using qemu) load the “Image” (for arm64) on memory location I want and I could run the kernel booting using `booti ker_add initrd_addr dtb_addr` command. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>As you know in arm64, the uImage format is not supported.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Then, when building linux kernel for arm (32 bit) using u-boot, what does “make LOADADDR=0x20008000 uImage” mean? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Regardless of this LOADADDR, we can load (from SD card or network) the uImage anywhere we want using u-boot shell. Then what is this LOADADDR?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Does it mean that when we run `bootm` command, the u-boot program relocates the kernel image inside the uImage to 0x20008000? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>(and the kernel built not using position independent, PC-relative addressing..using hard absolute addresses..)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Some years ago, we used kernel start address during the build and I had to load the kernel image exactly on that address. But this time I could load ‘Image’ anywhere I want and could run it. Why?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Is it because I (not knowingly) compiled the arm64 ‘Image’ using position independent address(-PIE option)?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>If someone with expertise could explain to me what’s happening here, I would really really appreciate it. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Thank you.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Chan Kim<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>