测试发现a33核心板有时无法正常启动，通过串口信息显示判断是uboot 对mmc初始化有时会出现问题：

[      0.770][mmc]: ************Try MMC card 2************

[      0.796][mmc]: mmc 2 2xmode config clk [      0.806][mmc]: mmc 2 data timeout 80 [      0.810][mmc]: smc 2 err, cmd 8,  DCE [      0.814][mmc]: Read remain data [      0.819][mmc]: mmc 2 mmc cmd 8 err 0x00000080 [      0.823][mmc]: mmc send ext csd failed [      0.827][mmc]: send ext csd faild [      0.830][mmc]: Change speed mode failed [      0.834][mmc]: ************SD/MMC 2 init error!!!************ [      0.840][mmc]: MMC: block number 0x1 exceeds max(0x0)

原因不明。

临时解决方案：当uboot检测到emmc初始化失败时reset cpu。

1. 修改驱动

具体需要修改lichee/brandy/uboot-2011-09/driver/mmc/mmc.c

在检测到mmc_startup失败后，调用reset_cpu(0)来重启cpu。

2. 编译打包

cd lichee/brandy/uboot-2011-09/

make distclean

make sun8iw5p1

make -j