基于rk356x u-boot版本功能分析及编译相关（一）

🎏技术驱动源于热爱，祝各位学有所成。

uboot的分支是next-dev历史版本v2017-09

uboot支持DM框架

DM 框架是 U-Boot 里现在所有驱动的框架模型统称，它主要包括 uclass、driver、device。U-Boot 的 doc

目录里可以找到官方详细的说明文档：

Uclass - a group of devices which operate in the same way.

A uclass provides a way of accessing individual devices within the group, but always using the same

interface. For example a GPIO uclass provides operations for get/set value. An I2C uclass may have 10

I2C ports, 4 with one driver, and 6 with another.

Driver - some code w