xref: /OK3568_Linux_fs/u-boot/board/varisys/cyrus/README (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunRebuilding u-boot for Cyrus
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3*4882a593SmuzhiyunThe Cyrus defconfigs are Cyrus_P5020_defconfig and Cyrus_P5040_defconfig.
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5*4882a593SmuzhiyunThey currently disable size optimization in order to avoid a relocation
6*4882a593Smuzhiyunbug in some versions of GCC. As the output size is a constant, the size
7*4882a593Smuzhiyunoptimization is not currently important.
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9*4882a593SmuzhiyunCyrus boots off a microSD card in a slot on the motherboard. This requires
10*4882a593Smuzhiyunthat the u-boot is built for the Pre-Boot Loader on the P5020/P5040.
11*4882a593SmuzhiyunIn order to reflash u-boot, you must download u-boot.pbl, then write it
12*4882a593Smuzhiyunonto the card. To do that from u-boot:
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14*4882a593Smuzhiyun> tftp 1000000 u-boot.pbl
15*4882a593Smuzhiyun> mmc write 1000000 8 672
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17*4882a593SmuzhiyunIf you want to do this via a card reader in linux:
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19*4882a593Smuzhiyun> dd if=u-boot.pbl of=/dev/sdX bs=512 oseek=8
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