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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><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I’m porting linux on an FPGA board which has only 8MB SRAM in place of DDR address range for now. (using linux-5.4.21)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>So this means, seen from software, the DDR memory exists only for 0x80000000 ~ 0x807fffff.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I loaded kernel image (Image) at 0x80080000 and it takes space to 0x8061d008. For there is so scare space, I loaded the dtb at 0x807fd000.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Now the kernel stops during setup_machine_fdt in setup_arch. I guess maybe it’s because the kernel could not setup fixmap for fdt. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>(I recently learned the kernel uses fixmap for the fdt and it requires 4MB separate pages)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I just started to look into early_fixmap_init function but can anyone tell me if this can be the real problem? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Isn’t it possible to use 8MB memory to run linux? (I’m doing this before the board is fully ready)<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>Thank you!<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></div></body></html>