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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,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I saw the head.S file for arm64 assumes the x0 register contains the address of the device tree (dtb).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>But some systems use ACPI table for handing hardware configuration to the kernel.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>If the system firmware and bootloader uses UEFI and ACPI, (and bootloader like grub), does the bootloader set x0 with dtb too?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>In this case x0 is not use?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Chan Kim<o:p></o:p></span></p></div></body></html>